2015 Journal by Cal Poly TAGA

CAL POLY

TAGA 2014-2015

Copyright ÂŠ 2015 California Polytechnic State University, San Luis Obispo, Technical Association of Graphic Arts, Student Chapter First Published in the United States of America by Cal Poly TAGA Student Chapter One Grand Avenue

Title of Paper â&#x20AC;˘ Author

San Luis Obispo, CA 93407 Printed at California Polytechnic State University, San Luis Obispo All right reserved. All material in this book has been compiled with the knowledge and prior consent of those concerned, but is published without responsibility for errors or omissions. Nothing in this publication shall be reproduced without the expressed written consent of the authors and editors. Every effort has been made to ensure that credits accurately comply with information supplied. We apologize for any inaccuracies that may have occurred.

iii

Hello! On behalf of California Polytechnic State University, San Luis Obispo, it is my honor to present to you our 2015 Technical Journal. This journal has always been produced entirely by students, and we are proud to say that we have continued the Cal Poly tradition of “Learn by Doing.” With the amazing facilities and resources within the Graphic Communication department provided by sponsors and donors, we were able to fully produce this journal within the GrC program and entirely at the hands of students. As always, this year’s student chapter was filled with self-motivated students that worked together to create a journal that they can all happily show to future employers as an example of how much they learned outside of the classroom. TAGA serves as an outlet for students to not only interact and connect with others interested in design and print production, but also to gain experience and knowledge in research and leadership.

Each of the TAGA officers actively look for opportunities to teach the members more than what they may experience in the classroom. I am so proud of the group I have led this year and what they accomplished. I am confident that everyone who was involved with this journal will go on to do great things! Sincerely,

Jordan Triplett lett TAGA Chapter President

TABLE OF CONTENTS

01 23 45

Photogravure Printing A History and Process Overview NIKOLE KNAK

Engraving a Gravure Cylinder Electromechanical vs. Direct Laser KRISTEN MINLSCHMIDT

Improving the Print Quality and Electrical Efficiency of Printed Electronics using Gravure Printing Technology SHANNON LING

65 91 113 136

Potential Areas of Growth in Rotogravure HANNAH STOMBLER-LEVINE

The Future of Gravure in the Printed Electronics Industry SARAH PILEGARD

Printed Electronics Applications for Publications ABEL MARQUEZ

Chapter Photos Acknowledgements Colophon

PHOTOGRAVURE PRINTING A HISTORY AND PROCESS OVERVIEW BY NIKOLE KNAK

2 7 10 15 17 19

Introduction

Research Methodology

Results & Discussion

Concluding Remarks

References

Author Biography

Abstract Photogravure printing is a subsection of rotogravure that is not greatly explored. While photogravure can be printed on a web press similarly to conventional rotogravure, it has a very different platemaking process that makes it a unique way to print high-quality photographs. Photogravure has an interesting historical background, originating from the founders of modern photography. Using a process of photochemical engraving, photogravure can reproduce photographs, as well as other repeated-pattern products. Unfortunately, due to costs in platemaking and soaring popularity in online advertisements, the main industry in photogravureâ&#x20AC;&#x201D;catalogs, magazines, and other forms of printâ&#x20AC;&#x201D;is in decline.

Photogravure Printing: A History and Process Overview • Nikole Knak

Introduction Photogravure is the method of printing high-quality continuous-tone photographs using a rotogravure cylinder. Unlike conventional rotogravure, which uses a stylus to engrave cells into the copper cylinder, photogravure uses a complex chemical process to dissolve the copper cylinder and create cells. While photogravure is technically rotogravure, the significantly different system used to produce images garners it special attention to those studying the gravure printing process. History and Background Photogravure is an intaglio process, which means that the image is engraved into a surface in order to be reproduced. Intaglio was invented by Italian Renaissance artists in the twelfth century (Katzman). The word intaglio means “engraved” or “cut in” in Italian (Pekarovicova). Intaglio is a method of printing where the image is carved into the plate or image carrier in a series of lines or dots. The plate is then inked and the image is printed onto a substrate. The first engravings were created by carving the image into soft copper by hand. Chemical etching was created around 1505 by using an etching needle to draw on a soft resin layer on a copper plate, then acid would penetrate the exposed copper layer, creating the image (Pekarovicova). Modern gravure printing resulted from the invention of photography in the 1800’s and the use of a rotating print cylinder. The inventions of photography and photochemical engraving are credited to French inventor Nicephore Niépce. In 1826, Niépce invented what he called “heliography” with the first photomechanical etched

3 printing plate (Lilien 17). His technique involved preparing a brass plate covered with Syrian asphalt, similar to bitumen. The Syrian asphalt would become white and insoluble when exposed to light. The plate would be exposed with an image that allowed some parts to shine through and others to block out light. The exposed areas would become Niépce’s View from the Window at Le insoluble, the dark areas were removed Gras, the first successful permanent with lavender oil, and the plate could photograph in 1826 or 1827. be etched as normal (Beguin). While Niépce’s invention was revolutionary, it took approximately eight hours to expose the pictures. In 1829, he formed a partnership with fellow-inventor Louis Jacques Mandé Daguerre (Lilien 17). Niépce and Daguerre worked to improve the heliograph process until Niépce’s death in 1833. Daguerre continued to work, creating the Daguerreotype in 1839. The Daguerreotype became widely popular because it developed the picture within thirty minutes (Microsoft Encarta). Daguerre’s process involved a plate of polished copper coated with light-sensitive silver halide. Once exposed, the image developed using an open flame and liquid mercury (White House Historical Associate). However, there were many significant drawbacks to the Daguerreotype. Aside from being a chemically dangerous process, the Daguerreotypes were very sensitive to friction and could easily be tarnished by the air. They also could not be reproduced; Daguerreotypes are similar to our Polaroid pictures (Microsoft Encarta).

Photogravure Printing: A History and Process Overview • Nikole Knak

4 During the same time Daguerre was experimenting with his version of photography, William Henry Fox Talbot, an English inventor, was working on his own method of capturing images and reproducing them. Talbot is typically seen as the inventor of modern-day photography, as well as photogravure printing. Talbot furthered the photomechanical production of printing plates by discovering the light sensitivity of chrome colloids. Talbot contributed to photography Daguerrotype of President with his “calotype” process, which reduced Abraham Lincoln. image exposure time to a few minutes or seconds depending on the strength of sunlight. On silver nitrate paper, a short exposure was needed and an image would be brought out with gallic acid. The image would be fixed in a wooden frame, waxed, and printed (Buckland 62). Talbot also developed technology that continuous tone pictures could be converted to halftone dots “by interposing a woven textile and making it suitable for the etching of a printing plate” (Lilien 20). This conversion to halftones was a significant discovery for engravers, as well as letterpress and lithographic platemaking (PrintWiki). Talbot patented his invention in 1852. His plates were made by coating steel with bichromated gelatin, drying the film, and exposing it to sunlight under objects that cast a shadow. Once the gelatin hardened, the non-hardened gelatin areas of the plates were etched in a solution of platinic chloride. The plates were printed on a cop-

5 per plate press, but it was soon realized that a grain was needed to hold the ink in the wider cells. In 1858, Talbot patented another method where plates were etched with ferric chloride and dusted with a copal resin powder, which secured the ink better to the plates and provided better tonal quality (Cartwright 194). Talbot’s precursor to modern-day photogravure printing was called “photoglyphic engraving,” patented in 1858. Bichromated gelatin was coated on a steel, copper, or zinc plate. The plate was exposed to create a photographic positive. The gelatin was hardened in the sunlight and the unhardened areas were washed away with a mixture of water and alcohol. Finely powdered gum copal was lightly sprinkled on the plate and heated to make a hard resin. The melted gum formed a pattern of dots that resisted the ferric chloride etching fluid. This etched away the metal plate that wasn’t covered in the hardened gelatin. The dots acted to retain ink during printing (Talbot). Talbot’s photoglyphic engraving appealed to publishers and illustrators because now pictures could be permanently preserved with printing. However, there was still the issue of Horatia Feilding, half sister of producing a photographic coating for Fox Talbot, plays the harp in this calotype. a cylinder that could be used for etch-

Photogravure Printing: A History and Process Overview • Nikole Knak

6 ing. In the 1860’s, engraver J.W. Swan used carbon tissue to solve the problem. “After exposure, the paper could be removed, and the exposed coating applied to another surface, such as a metal plate— or cylinder” (PrintWiki). In 1879, Karl Klic combined all of the previous inventions to create the first modern gravure press—the rotary intaglio textile press with Talbot’s halftone screen process and Swan’s carbon tissue coating. Klic teamed up with Samuel Fawcett, an engraver at a textile printing company. In the early 1890’s, they developed “new techniques for photoengraving, and began commercial printing of intaglio art prints” under the name of Rembrandt Intaglio Printing Company (PrintWiki). The company used reel-fed gravure for the production of art prints, which were then sold as heliographs at art shops (Lilien 29). Around 700 prints were printed per hour (Lilien 31). Engravers could not compete with the quality and speed of the Rembrandt Company and their copper cylinders. The company essentially monopolized the photogravure industry by forcing employees to a strict secrecy policy. For example, one employee noted: To prevent the realization that the prints were made on a reel-fed press, we never used the word cylinder. We always talked of plates. This became second nature to all Rembrandt employees, so much that few friends who still survive from those early days still say plates when we speak of gravure cylinders. A few years later when Rembrandt prints were widely discussed the main question always was how one could print from flat plates on to a continuous web of paper (Lilien 49).

7 In 1906, the Rembrandt Company began producing colored prints using three “plates” (Lilien 52). Eventually, the company’s cylinder plate and web printing technique was exposed to the world and other companies and inventors began to expand the photogravure printing process.

Research Methodology Conventional Photogravure Continuous-tone positives are made from the separation of negatives. Two exposures are made on each sheet of gravure tissue—one from the positive and one from a gravure screen. The tissue has a bichromated gelatin coating which is hardened by exposure. This gelatin coating is then transferred to a copper cylinder and the unhardened gelatin is washed away. The remaining image is used as a resist for controlling Conventional photogravure print. the etching of the copper (Yule 8). Henderson Process A halftone positive is made instead of a continuous-tone positive. Additional exposure through a gravure screen is omitted. A resist similar to those used in photoengraving is coated on the metal, instead of using a gravure tissue. This process is not widely used because the relative depths of the etched highlight and shadow dots are not ideal for transferring ink to paper (Yule 8).

Photogravure Printing: A History and Process Overview â&#x20AC;˘ Nikole Knak

Dultgen Process A halftone positive and a continuous-tone positive are made and printed into the gravure tissue. The etched highlight dots are smaller and somewhat deeper and do not wear as rapidly (Yule 8). Hard-Dot Process The gravure tissue is exposed to a continuous-tone and halftone positive. The halftone positive is made from a halftone negative, which was made from the continuous tone positive (Yule 8). A silver-halide photographic film can be used in place of gravure tissue. It can be exposed to a continuous-tone positive using a contact screen so it has a combination of a halftone and continuous tone image (Yule 9). The photomechanical processes to reproduce an image photogravure are different from the other processes used for color photography, specifically the large number of copies that can be made, reproducing a picture rather than an original scene, and using halftone screens (Yule 11). Web-Rotary Photogravure Machines While photogravure can be printed sheet-fed, it is most commonly printed with a web press. Web rotaries have evolved from machines that were used in textile printing. A cylinder is carried on a mandrel which is driven by a spur wheel. The cylinder receives ink from an inking roller, which revolves in a trough of ink. The ink is scraped from the surface of the cylinder with a doctor blade, a flexible steel blade held by a frame. â&#x20AC;&#x153;The doctor blade is given a slight transverse motion in a direction parallel to the cylinder axis to equalize the wear on itâ&#x20AC;? (Cartwright 130).

9 The paper is taken from the reel that is secured with a reel shaft. A brake drum is connected to the shaft to provide tension control on the web. Paper is led over guide rollers and passes between the upper surface of the print cylinder and a rubber impression cylinder (Cartwright 130). Methods of Drying the Ink When printing with multiple colors, the ink must dry before the web passes into the next color unit, or before it is re-reeled, folded, or cut. There are several methods to dry the ink. One method is carrying the web over rollers long enough for the air to dry the ink. Another method is passing the web over heated rollers. Electric radiators can be used with heat being directed to the ink, but they are not always sufficient when working at high speeds. Air can also be blown over the ink. The last method is removing the area with suction, which also removes the vapor from the solvent in the ink (Cartwright 134). Perfecting and Mutlicolor-Web Rotaries Perfecting web rotaries consist of two units. In the first unit, the web receives an impression on one side and then passes over a steam-heated drum to the second unit, where it is printed on the back (Cartwright 135). Multicolor photogravure prints can be made using one unit per color. Lateral and circumferential adjustments must be made to the cylinders in order to ensure good color registration. Drying arrangements must also be considered to ensure as little changes in the web dimensions as possible. Some presses will heat the web to

Photogravure Printing: A History and Process Overview • Nikole Knak

dry the ink, then pass the web over a series of cooling rollers (Cartwright 136).

Results & Discussion Preparation of Images Photogravure prints can be made with either photograph originals or line originals. If line originals are used, the lines must be sharply defined and all equally black. It is ideal to also make the line drawings larger than needed so that they can be scaled down in reproduction if needed. Scraperboard can be used for line art, although there is a risk of a moiré pattern forming when the gravure screen is used (Cartwright 1). If photographs are used, glossy photos are reproduced the best; if a photo’s surface is too rough, vaseline can be applied to the surface to smoothen it. Photos that are neutral black are ideal, while prints that are sepia-toned should be avoided (Cartwright 1). A positive transparency is made from a negative. The film positive should be made to the desired print size. It is contact-printed under ultraviolet light to light-sensitive carbon tissue. The light through the film positive changes the melting temperature of the gelatin on the carbon tissue. The areas exposed to light are “hardened” and the non-exposed areas stay the same (Katzman). Preparation of Layout A layout sheet showing the exact position of pictures, captions, and text should always be prepared in order to ensure the work will be

11 handled efficiently and enough space will be allotted for each element. For book work, knowledge of the printing and folding machines is required, as well as communication between the printing and binding departments. Knowledge of imposition is also crucial. The weight of paper should be taken into account when imposing four-, eight-, sixteen-, and thirty-two-page sections, as well as knowledge of irregular impositions, in order to make folding and stitching easier. Front-lay and side-lay edges should be indicated so that the stock is correctly positioned with the cylinder (Cartwright 5). Copper Electroplating The cylinders have a thin layer of copper electro-deposited or electroplated on an iron roller or cylinder. A perfect cylindrical form is obtained through grinding and polishing the copper. Aluminum has been used instead of iron to combine lightness and solidity, but copper tends to not adhere to it as well during the electroplating process. Brass and copper are excellent for electroplating the copper, but they drastically increase the cost of the cylinder (Cartwright 54). If the core of the cylinder is iron, the cylinder must be immersed in a copper cyanide bath to avoid future electrolyte contamination during the electroplating process. The iron must be thoroughly cleaned, usually by sand blasting. It is then scrubbed, rinsed with a hose, swabbed with a nitric acid solution, and washed again. After it is cleaned, it is immediately immersed in the depositing bath to avoid being tarnished (Cartwright 55). The cylinder is placed on a mandrel and is dipped into the electrolyte solution, where it is slowly rotated. â&#x20AC;&#x153;Pure copper anodes are sus-

Photogravure Printing: A History and Process Overview â&#x20AC;˘ Nikole Knak

pended on copper hooks from brass rods on each side of the vatâ&#x20AC;? (Cartwright 55). The electrolyte solution is made of copper carbonate, sodium cyanide, sodium carbonate, and water, and is heated to a minimum of 60 degrees Fahrenheit. The electrolyte solution should only be enough to cover the cylinder. A cathode surface is immersed in the solution to provide a negative current, either from accumulators or a motor generator. Pure copper anodes are added to the solution. The solution is agitated to shorten the copper deposition time, by constantly circulating the solution. Defective deposits can occur from impure anodes, acid contents that are too low, temperatures that are too high, or current densities that are too low (Cartwright 56). Preparing the Plate The copper plate must be thoroughly cleaned and polished. The edges of the plate are beveled to avoid damaging the paper during printing (Katzman). The cylinder is dipped into a water bath and a flat grinding stone is placed on the cylinderâ&#x20AC;&#x2122;s surface. The stone moves parallel with the axis of the cylinder. The cylinder is then polished and buffed with charcoal to smoothen the surface (Cartwright 57). Once the cylinder is ground and polished, it is dusted with rosin or asphaltum, which resist acid, and is heated so the resists adhere to the plate (Katzman). Transferring Image to Plate The carbon tissue is adhered to the plate. It is soaked in hot water to soften the gelatin, which allows the paper base to separate from

13 the gelatin. The portions of the gelatin that were not hardened are soluble and are washed away. The gelatin image that remains will act as an acid resist when the plate is etched; it is then dried to the copper (Katzman). Etching the Plate The plate goes through a series of etching baths. The sequence begins in proportion to the thickness of the gelatin and the viscosity of the ferric chloride bath. The viscosity of the ferric chloride controls the speed that it penetrates the gelatin. The ferric chloride eats at the plate, resulting in cells of varying depths (Katzman). Printing Once the cylinder is washed, the image can finally be printed. A low-viscosity ink is spread over the cylinder and Etched polymer photogravure plates. worked into the engraved cells. The surface is wiped with a doctor blade, leaving ink only in the cells. The printer places a piece of dampened paper over the plate and covers the paper with felt for padding as it passes through the press. Rollers force the paper into the cells, printing the image (Katzman).

Photogravure Printing: A History and Process Overview â&#x20AC;˘ Nikole Knak

Paper Any paper that is smooth and absorbent enough to pick up ink without excessive pressure can be used in photogravure. Ideally, the paper should be smooth with a matte finish (Cartwright 128). Inks The ink used in gravure printing is completely different from letterpress or lithography inks. Gravure inks are fluid and have low surface tension so it can easily fill the cells and still be wiped off cleanly with the doctor blade. The pigments must be very fine to avoid scratching the copper. The ink must also be able to dry quickly. Gloss inks with a high resin content are popular with magazine covers and book jackets, mostly because matte inks show shiny markings when rubbed (Cartwright 125). Water-based gravure inks are used for security printing, such as check backgrounds or cheap newspapers. While their water solubility is important with security printing, it isnâ&#x20AC;&#x2122;t practical for magazine covers if they are exposed to outdoor dampness (Cartwright 127). Photogravure Applications Photogravure is commonly used for security printing, especially with postage stamps. Special attention must be taken in order to ensure uniform ink density on all of the stamps (Cartwright 174). Banknote papers and passports can also be printed photogravure. Photogravure is used for continuous designs, such as wallpaper, made possible because of the lack of a printing gap in the copper cyl-

15 inder (Cartwright 175). Perhaps the most common examples of photogravure are magazines, catalogs, and some newspapers because of the high-quality images that can be printed. According to the Gravure Association of America, in 2011 over $300 million was spent by various publications in the gravure industry. Some of the publications include Hearst, AARP, New York Times, National Geographic, Reader’s Digest, and Playboy. Some magazine titles that previously printed photogravure include TV Guide, Glamour, and Parents. However, photogravure printed ads have decreased by 40% in the last five years. Print advertising spending itself was $36 billion in 2011, and dropped to $33.8 billion in 2012; on the other hand, online advertising is seeing huge growth percentages. These trends in printing are results from the needs of businesses to promote digitally on mobile and social networking devices, and the instantaneous “turn around” for posting online, versus printing (Martin). Currently there is one gravure ink supplier in North America; there are two gravure publishers in North America, R.R. Donnelly and Quad Graphics. The lack of demand for gravure is also causing paper mills to no longer provide paper for web gravure. Although gravure and photogravure printing is seeing a declining trend, it is still relatively stable in the printed media market (Martin).

Concluding Remarks Photogravure printing’s unique history and processing method truly makes it an artistic printing process. Reproducing high-quality continuous-tone images requires a strong attention to detail and a great

Photogravure Printing: A History and Process Overview â&#x20AC;˘ Nikole Knak

16 knowledge for photographic color reproduction. Due to high costs and decreasing popularity as our society moves toward an electronically-based advertising and marketing scheme, the photogravure, and in general rotogravure, industries are in a slow decline. Polymer photogravure plate being imaged.

References Buckland, Gail. Fox Talbot and the Invention of Photography. Boston, David R. Godine, 1980. Print. Beguin, Andre. Bitumen. Printmaking Dictionary. 28 February 2014. Web. Calotype of Horatia Feilding playing the Harp. Digital image. Wikipedia. Web. Cartwright, H. Mills. Photogravure. Boston, American Photographic Publishing Co., 1939. Print. Daguerreotypes. Historic Photographs. The White House Historical Association. 27 February 2014. Web. Daguerreotype of President Lincoln. Digital image. Good Bokeh. Web. Exposed photogravure plates. Digital image. Photogravure at Renaissance Press. Web. Gravure. PrintWiki. 1 March 2014. Web. Katzman, Mark. Art of the Photogravure. Photogravure.com. 17 February 2014. Web. Lilien, Otto M. History of Industrial Gravure Printing. London, Lund Humphries Publishers Ltd., 1972. Print. Louis Daguerre. Microsoft Encarta Online Encyclopedia. 2008. 27 February 2014. Web. Martin, Bill. Status of Publication Gravure in North America. Gravure Associate of America. 25 September 2012. 28 February 2014. Web. Pekarovicova, Alexandra. Gravure Printing. Western Michigan University. 19 February 2014. Web. Photogravure direct to plate print. Digital image. Bridges. Web. Photogravure plate exposing process. Digital image. Polymer Photogravure. Web.

Photogravure Printing: A History and Process Overview • Nikole Knak

Pietzcker, Eva. Photogravure. Printmaking Studio. 2014. 28 February 2014. Web. Stulik, Dusan C. Photogravure. The Getty Conservation Institute. Los Angeles, The Getty, 2013. Web. Talbot, William Henry Fox. Description of Mr. Fox Talbot’s New Process of Photoglyphic Engraving. London, Peter and Galpin, 1858. Print. View from the Window at Le Gras by Joseph Nicéphore Niépce. Digital image. The Sociable. Web. Yule, J.A.C. Principles of Color Reproduction. USA, Graphic Arts Technical Foundation, 2000. Print.

NIKOLE KNAK I am a 4th year Graphic Communication major with a concentration in Design Reproduction Technology. I am the marketing manager for the student-run Mustang News and Mustang Media Group. I am also the student representative for College Media Business and Advertising Managers (CMBAM). After college, I hope to enter the marketing industry, working with cosmetics or printed electronics. I discovered an interest in printed electronics after taking a course in the subject this year, working on a research project under a professor, and attending the IDTechEx conference in November. I will also be attending the FlexTech conference in February. I am originally from Redding, a small town in Northern California near Oregon. In my spare time, I love playing my saxophone, exploring the uses of social networks, and reading.

ENGRAVING OF A GRAVURE CYLINDER ELECTROMECHANICAL VS. DIRECT LASER BY KRISTEN MINLSCHMIDT

24 25 34 37 39 41

Introduction

Research Methodology

Results & Discussion

Concluding Remarks

References

Author Biography

Abstract There are two prominent methods for engraving gravure cylinders in the industry todayâ&#x20AC;&#x201D;electromechanical engraving and direct laser engraving. The first is a contact process, which uses a lathe-style cutting machine and a diamond stylus to engrave cells into a copper-plated cylinder. The latter is a non-contact process that uses a laser beam to engrave cells into a zinc-plated cylinder. Both electromechanical and direct laser engraving have their benefits and their drawbacks. Electromechanical engraving has been the forerunner in the industry for a long time, but direct laser engraving is starting to gain prominence.

Introduction

Engraving a Gravure Cylinder â&#x20AC;˘ Kristen Minlschmidt

Time and cost to engrave a cylinder are major factors that drive the gravure printing industry. There are two predominant methods for engraving gravure cylinders, electromechanical engraving and direct laser engraving. Each method is continually striving to improve its performance in an attempt to either maintain or gain influence in the gravure market. E l e c t r o m e ch a n i c a l l y engraving a cylinder involves using one or more engraving heads, which each consist of three diamonds, to generate cells on a copDirect laser engraved cells compared to per-plated cylinder. The electromechanically engraved cells. first is the diamond stylus, which penetrates the copper plating of the cylinder and produces cells of varying sizes and thicknesses. The second diamond, which can sometimes be a sapphire, is the shoe and it rides along the surface of the cylinder determining the depth of each cell. The burr cutter, the third and last diamond, removes excess copper left behind when the diamond stylus engraves each cell. Electromechanical engravers are capable of engraving up to 9,600 cells per second, a number that has grown in recent years as further improvements have been made to the process. Due to the use of

25 a diamond as the engraving tool, the cells produced in this method are diamond-shaped. This cell shape is the cause of the serrated edges that are generally associated with gravure, especially when printing line art and type. All imperfections aside, electromechanical engraving has been and remains the most commonly used engraving process in the gravure industry. The latest promising development in gravure cylinder engraving technology is direct laser engraving. Laser engraving a gravure cylinder is a non-contact method of engraving in which a laser beam penetrates an electroplated zinc layer on the cylinder to produce cells of varying sizes and thicknesses. The cylinder is most commonly electroplated with zinc instead of copper because zinc does not have as reflective a surface as copper. The cells produced in this method are typically spherical, relieving some of the unwanted serrated type and line art produced with electromechanical engraving, while other unique shapes may also be generated. Direct laser engravers are capable of engraving up to 70,000 cells per second, substantially faster than electromechanical engraving. These machines accomplish the goal of reducing the time and cost of engraving gravure cylinders.

Research Methodology Using secondary research, the similarities and differences between electromechanically engraving a gravure cylinder and direct laser engraving a gravure cylinder were analyzed in an attempt to determine if either method is more effective than the other and what might prompt a switch from electromechanical engraving to direct laser engraving.

26 Electromechanical Engraving

Engraving a Gravure Cylinder â&#x20AC;˘ Kristen Minlschmidt

Electromechanical engraving has been the prominent method of engraving gravure cylinders since its creation. â&#x20AC;&#x153;This truly revolutionary development ushered in the industrial production of gravure cylinders for illustration, decorative, and packaging printingâ&#x20AC;? (Wessendorf). The process of electromechanically engraving

Electromechanically engraved cells of varying cell depths.

involves a great deal of time to produce a single print-ready cylinder and, consequently, costs a great deal of money. Progress has been made to improve the speed of electromechanical engraving, but larger, detailed jobs can still take from hours to full days to engrave. Electromechanical engravers come in two main varieties, those for the publication market, which typically consist of eight to sixteen engraving heads, and those for the packaging market, which frequently only use one engraving head. The use of multiple engraving heads helps to minimize time needed to engrave a cylinder for jobs

27 that are more time sensitive, like those in the publication market. If using more than one engraving head, each head must be calibrated prior to engraving to ensure cells are being engraved consistently across the cylinder. As previously mentioned, electromechanical engraving produces a diamond cell shape, leading to the serrated edges associated with gravure, most commonly seen in line art and type. The depth of a cell is controlled by the impact of the stylus, while the cylinder rotation and lateral head movement control the width. The Diamond stylus is capable of engraving cells between the angles of 105° and 135°, and the steeper the angle of the stylus, the greater the possible depth of a cell. Electromechanically engraved cells can be up to 200 microns wide and 50 microns deep. The desired size and shape of the cells are determined by the color of the ink being applied to the cylinder and the substrate being printed on. Improvements are constantly being researched to help diminish the serrated edges. Hell Gravure Systems recently premiered their “Xtreme” electromechanical engraver, which utilizes a separate engraving that follows behind the main head, filling in the gaps between cells and creating a smoother line. Cell shapes have been observed to directly correlate to a cylinders’ ability to release ink onto a substrate. Ink release can be an issue with electromechanically engraved cells, as the cell walls are not consistently even. It is common to use Electrostatic Assist, or ESA, when printing with electromechanically engraved gravure cylinders to achieve better ink release, particularly from the highlight cells.

Engraving a Gravure Cylinder • Kristen Minlschmidt

“For instance, to get a 3% dot on the paper may require a 20% dot on the cylinder” (Gravure Education Foundation, 190). The different cell shapes generated in both methods of engraving also influence printing factors such as density, gloss and tone reproduction. The depth of a cell determines the volume of ink to be transferred to the substrate and therefore the color density on the substrate after printing. Electromechanical engraving allows for varying cell thicknesses and therefore a range of densities on the printed piece. It was observed in the study “Gravure Printability Comparison of Laser & Electromechanically Engraved Cylinders” that electromechanically engraved yellow cells print better density values than laser engraved yellow cells, but electromechanically engraved black cells print poorer density values than laser engraved yellow cells. “The difference could come from the cell shape differences on the cylinders” (Rong, Gravure Printability), electromechanical having the diamond shape and laser utilizing a spherical shape for cyan, magenta, and yellow, and a plum-bloom shape for black. The shape of a cell has also been shown to affect gloss and tone reproduction when printing. Professor Rong’s study found that the substrates printed using the laser engraved cylinders showed higher gloss values. It is not hard to recognize that these three factors, among others not discussed, are not consistent for electromechanically engraved cells. Direct Laser Engraving In the late 1990’s, Max Daetwyler AG introduced a major development to gravure cylinder engraving, direct laser engraving. This new engraving technology dramatically reduced the time and cost of pro-

29 ducing print-ready cylinders; they were “8.5 times faster than the fastest electromechanical engravers of the current generation” (Wolf). Convincing the industry to adopt the new technology is not a simple task, though. Pre-existing gravure print facilities have invested their money into electromechanical engraving equipment, making the decision to invest in new direct laser engraving equipment costly. Other costs associated with this new technique may also outweigh some of its many benefits. Direct laser engraving into zinc is a

Direct laser engraved cells of varying cell depths.

potentially expensive venture “due to the complexity of handling the new engraving material” (Beißwenger). However, zinc has excellent qualities for absorbing ample light from the laser beams, and it can be easily plated with chromium, giving it the resistance of a conventional cylinder and making it the optimum material to work with (Lasers in Engraving).

Engraving a Gravure Cylinder • Kristen Minlschmidt

30 One of the biggest benefits of direct laser engravers is their capability to generate spherical cell shapes, which have been successful in relieving some of the serrated edges seen in line art and type that are created in electromechanical engraving. Laser engraving can also produce other special cell shapes that are impossible to create in electromechanical engraving, such as the plum-bloom cell shape, which further helps to print sharper, smoother lines. The plum-bloom cell shape is an example of a masterscreen, which consists of seven small spherical cells, and is commonly used for printing fine text and shapes with black ink. The cell walls produced with the spherical shaped cells are more even and consistent across the cylinder, resulting in a more consistent print. The direct laser engraving system is more stable and predictable than electromechanical engraving, guaranteeing the creation of optimum cell shapes across the cylinder with even cell walls. “The printing forms give an exactly defined ink transfer rate for each screen due to the geometric precision of direct laser engraving” (Gravure Education Foundation, 197). The accuracy of the laser engraving process contributes to the better overall ink release from the cells. Direct laser engraving eliminates time during the engraving process, saving print facilities money in the long run, and the better ink release from laser engraved cells is an additional source of saved money. “Tests have proven that the laser cell configuration provides a better ink release, resulting in substantial ink savings” (Gravure Education Foundation, 197). Laser-engraved cylinders are less affected by ESA than electromechanically engraved cylinders, but there is also less of a need to use ESA because they achieve a better ink release initially.

31 As previously noted, the method used for engraving gravure cylinders can affect numerous printing factors, including density, gloss and tone reproduction. Direct laser engraving consistently produces high density and high gloss prints of different colors on multiple substrates, as demonstrated in Professor Rong’s study of gravure printability. This method of engraving has also been shown to yield very good tone reproduction. “The various possibilities for controlling direct laser engraving enable the creations of gravure cells whose depth profiles can, to a large extent, be freely select- ed. This makes it possible to fully exploit the continuous tone properties of gravure printing” (Beißwenger). Electromechanical versus Direct Laser Engraving in Common Gravure Printing Issues Many studies have been conducted to test the performance of electromechanical engraving and direct laser engraving in relation to common issues faced in the gravure printing industry. These studies have focused on the many factors that gravure printers must take into consideration when deciding what method to use for engraving cylinders and, more specifically, what cell shapes and sizes best suit the jobs they regularly print. These factors concern the printability of the two engraving methods, or how well the ink will be able to transfer from the cells to the substrate. The substrate on which ink is being laid is a main consideration that affects the choice of cell characteristics. Metals and plastic films take ink from the cells very differently than paper or corrugated board. “Laser engraving is ideal for the reproduction of soft vignettes and small fonts on substrates such as alu-

Engraving a Gravure Cylinder â&#x20AC;˘ Kristen Minlschmidt

Diagram of electrostatic assist being used to decrease the issue of missing dots.

minumâ&#x20AC;? (JanoschkaWorldWide, Direct laser engraving). The need to employ ESA to achieve better ink release will also influence the cell choice, as it affects diamond-shaped cells differently than spherical cells.

33 Another prevalent issue, common across multiple printing processes, is dot gain, which is indicated by ink transfer and spreading in a substrate. Referring to the study “Gravure Printability Comparison of Laser & Electromechanically Engraved Cylinders” conducted by Professor Xiaoying Rong, in which five different substrates were run through a gravure press using an electromechanically engraved cylinder and a direct laser engraved cylinder, it was observed that the dot gain curves of laser-engraved cylinders were closer together than electromechanically engraved cylinders. Dot-gain curves, also referred to as tone curves, were the tools used to measure the amount dot gain of each color in both methods of engraving. The maximum dot gain of the electromechanically engraved cells was recorded at 50 percent, compared to a 30 percent maximum dot gain with direct laser engraved cells. Dot gain was also observed to be larger when engaging ESA than without it, since more ink was consistently being re- leased from the cells of both engraved cylinders. A further recurring problem, specific to the gravure printing process, is missing dots, or snowflaking, where ink is not transferred from the engraved cells to the substrate. This problem correlates to ink release, which is a known problem in gravure, especially in the highlight cells, due to the quick-drying, solvent-based inks that are typically used. In a subsequent study performed by Professor Xiaoying Rong, “The Study of Missing Dots of Electromechanical and Laser Engraved Cylinders”, the ink transfer differences between the two methods of engraving were evaluated by printing samples from both engraving processes on five different substrates. It was determined that the use of ESA generated great results in improving the

Engraving a Gravure Cylinder • Kristen Minlschmidt

issue of missing dots. ESA corrected the issue more significantly in electromechanical engraving then in direct laser engraving, which supports Professor Rong’s previous data claiming laser engraving is less affecting by the use of ESA. However, “when there was no ESA applied, the ink release of laser engraved cells was better than [the] diamond shaped electromechanically engraved cells” (Rong, Study of Missing Dots).

Gravure cylinder cell measuring device.

Results & Discussion Both electromechanical engraving and direct laser engraving have benefits and drawbacks. It is hard to claim whether one method is more effective overall than the other. Electromechanical engraving has a strong hold in the gravure industry, with large investments having already been made into the equipment. The quality of prints

35 produced using electromechanical engraving is diminished by the time and cost of the engraving process and defects like the serrated edges, but efforts are constantly being made to find improvements. Direct laser engraving, on the other hand, is slowly gaining in popularity due to its high quality production, but remains behind electromechanical engraving in the market because companies in the industry cannot justify investing in new equipment when what they currently own does the job well. For years, electromechanical engraving was the front runner with no true competition, but as other printing processes and methods of engraving began to grow in popularity, manufacturers were compelled to explore all the options available to improve the process. The use of electrostatic assist has been utilized to improve ink release and therefore density and tone reproduction, as well as correcting issues like snowflaking. Manufacturers are also constantly seeking ways of alleviating the unappealing serrated edge created by the diamond stylus, but at a cost that is not always feasible for gravure print facilities, since their production costs are already high in comparison to other printing processes. Being a reliable, high quality method of printing, companies are also unable to justify replacing functioning electromechanical engraving equipment to invest in up-and-coming technology, all deficiencies aside. On the other hand, the process of direct laser engraving directly helps to relieve the serrated edges seen in line art and type that are created in electromechanical engraving. It also has a better ink release, allowing for improved density, tone reproduction, and

Engraving a Gravure Cylinder • Kristen Minlschmidt

has a lower ink usage, saving print companies money in the long run. This engraving method is also faster, and it costs less to produce print-ready gravure cylinders than electromechanical engraving. Due to the increased speed of engraving, jobs using direct laser engraving have the potential to be executed on demand, or just in time. “Printing behavior, print quality, process reliability, and cost-effectiveness are all improved [with direct laser engraving]” (Beißwenger). Both methods of cylinder engraving have been shown to function well in publication and packaging. Certain characteristics of the cells produced by electromechanical and direct laser engraving can affect what applications and markets there are better suited for. The spherical shape of cells generated with direct laser engraving relieve the serrated edges produced in electromechanical engraving, making laser engraving more suitable for printing line art and type. Electromechanical engraving has proven to be dependable across markets and when used with a variety substrates. “Like no other process, [electromechanical engraving] has repeatedly succeeded in adapting to changes and varied market requirements… through innovative solutions” (Wessendorf). The time and money spent engraving gravure cylinders is the major concern for both the printers and producers of gravure equipment. In order to remain in competition with offset lithography and flexography printers, gravure facilities need to lower the time and cost of production, and the easiest way to approach this goal will be to address those factors in the process of engraving gravure cylinders. Being capable of generating upwards of 70,000 cells per second,

37 direct laser engraving can achieve that goal. Laser-engraved cylinders offer a better cost-benefit ratio in the long run (Wolf). Another cost to be considered is the wear of equipment over time in a contact process like electromechanical engraving, where small parts, like the diamond in the engraving head must be replaced. In a noncontact process like direct laser engraving there will be no issue of wear on the engraving head of a laser engraver, saving the print facility an additional cost (NIIR). Nevertheless, as mentioned before, the cost of investing in laser engraving equipment when a company already owns functioning electromechanical engraving equipment might deter gravure print companies from making the switch.

Concluding Remarks Where will electromechanical and direct laser engraving fit into the future of the gravure printing industry? Regardless of engraving process, the overall goal in the industry is to produce the best possible prints, and developments are constantly being made in both electromechanical engraving and direct laser engraving to improve the quality of printing on gravure presses. These improvements are necessary to compete with other growing print markets like offset lithography and flexography, and have thus far been successful in doing so. Even though laser engravers are gaining ground in the gravure market, electromechanical engravers remain the dominant choice for engraving equipment. In their video demonstrating electromechanical engraving, JanoschkaWorldWide stated, â&#x20AC;&#x153;Electromechanical engraving is one of the conventional engraving technologies. With its reliable and high quality results, it belongs to the well estab-

Engraving a Gravure Cylinder • Kristen Minlschmidt

lished engraving techniques in the market”. While electromechanical engraving is well established, other sources like to speculate, “laser engraving may one day become the dominant engraving technology” (Gravure Education Foundation, 194). Not only are new engraving methods being explored, but new markets are on the horizon for the gravure industry. Publications were a large focus in gravure for a long time, but packaging is growing in the industry, and entirely new ventures like printed electronics are being researched. The growing competition in existing gravure markets and entry into new markets makes the need for a consistent, high quality engraving system necessary. The industry is currently remaining focused on electromechanical engraving, but direct laser engraving is quickly gaining ground. Gravure cylinder engraving equipment is a hefty initial investment no matter the engraving method. Still, printers in the gravure industry are having a hard time justifying re-investing in direct laser engraving equipment when they already have electromechanical engraving equipment that does the job sufficiently, and this fact may continue to drive the industry until their markets push them in another direction.

References Beißwenger, Dr. Siegfried, Max Rid. “The Physics of the Gravure Cell and The Consequences for Engraving Copper Gravure Forms.” Hell Gravure Systems GmbH. 2004. Web. 4 Feb. 2014. PDF. <http://www.hell-gravure-systems.com/_uploads/files/ HELL_ Fachartikel_040407_e.pdf> Daetwyler, Max. “Direct Laser Engraving New Prospects for Gravure Printing.” 22 March 2005. Microsoft Powerpoint File. Electrostatic assist. Digital image. IGGESUND Holmen Group. Web. Gravure cylinder cell measuring device. Digital image. Heimann Measuring Devices. Web. Gravure Education Foundation. “Gravure Cylinder Engraving.” Gravure: Process and Technology. Rochester, NY: Gravure Association of America and Gravure Education Foundation, 2003. 175-255. Print. JanoschkaWorldWide. “Direct laser engraving of rotogravure cylinder by Janoschka.” Online video. Youtube. Youtube, 6 Mar. 2013. Web. 21 Jan. 2014. JanoschkaWorldWide. “Electromechanical engraving of rotogravure cylinder Janoschka.” Online video. Youtube. Youtube, 6 Mar. 2013. Web. 21 Jan. 2014.

Laser engraving versus mechanical engraving. Digital Image. Janoschka. Web. “Lasers in Engraving.” Gravure News. Web. 4 Feb. 2014. PDF. <http://www.era.eu.org/ upload/LasersinEngraving.pdf> NIIR Board. “Gravure Printing.” The Complete Book on Printing Technology. Delhi: Asia Specific Business Press, Inc., 2003. 562-569. Print.

40 Rong, Xiaoying. “Gravure Printability Comparison of Laser & Electromechanically Engraved Cylinders.” Gravure Association of the Americas. Feb. 2004. Web. 18 Jan. 2014. <http://www.gaa.org/tech-articles/gravure-printability-comparison-laser-electromechanically-engraved-cylinders>.

Engraving a Gravure Cylinder • Kristen Minlschmidt

Rong, Xiaoying. “The Study of Missing Dots of Electromechanical and Laser Engraved Cylinders.” 2007. Web. 18 Jan. 2014. <http://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1018&context=grc_fac> Wessendorf, Ansgar. “50 Years of Electromechanical Engraving.” Hell Gravure Systems. 2010. Web. 23 Feb. 2014. <http://www.hell-gravure-systems.com/_uploads/files/50_ years_of_electromechanical_engraving.pdf>. Variable cell depth of direct laser engraved cells. Digital image.Janoschka. Web. Variable cell depth of electromechanically engraved cells. Digital image.Janoschka. Web. Wolf, Kurt K. “Laser Gravure Poised to Replace Mechanical Engraving.” Seybold Report. Analyzing Publishing Technologies 2.13 (2002): 10, Academic Search Premier. PDF. 4 Feb. 2014.

KRISTEN MINLSCHMIDT I am a fourth year Graphic Communication major at Cal Poly with a concentration in Graphic Communication Management and a minor in Packaging. On top of participating in TAGA as this year’s Vice President, I am also a member of Cal Poly’s Phoenix Challenge team, a competitive team that works to redesign and create packaging and other printed pieces using flexographic printing technologies. I am also a member of the Graphic Communication department’s social club Mat Pica Pi. After college, I plan to enter the packaging industry doing a mix of design work and production. After my internship experience working with Hewlett-Packard this past summer, I would specifically love to end up working in the developing industry of digitally printed packaging. I am originally from Tehachapi, CA, a small mountain town in central California. In my spare time, I love volunteering with the animals at our local humane society, hiking all along California’s beautiful central coast, and traveling as much as I can.

IMPROVING THE PRINT QUALITY AND ELECTRICAL EFFICIENCY OF PRINTED ELECTRONICS USING GRAVURE PRINTING TECHNOLOGY BY SHANNON LING

46 46 57 58 59 61

Introduction

Research Methodology

Results & Discussion

Concluding Remarks

References

Author Biography

Abstract The projected growth of the printed electronics industry is steadily increasing at a high rate. Several different printing techniques and their benefits in printing electronics have been examined. The gravure method specifically provides many advantages in terms of quality and efficiency compared to other processes. The following research paper discusses the main issues associated with the gravure methodâ&#x20AC;&#x2122;s production of printed electronics. It also suggests changes that can be implemented to fix these issues in order to manufacture the highest quality final product.

Print Quality and Electrical Efficiency of Printed Electronics â&#x20AC;˘ Shannon Ling

Introduction As the world becomes more digitally focused, opportunities for growth in the print industry would appear to be limited. However, recent developments emerging from graphics printing technology are being applied to produce printed electronic products. The printed electronics industry is an emerging technology, producing items such as radio-frequency identification tags, sensors, and display technologies. This printing technology is more cost efficient than other manufacturing methods, and it has generated much interest in printed electronics because of the potential growth it may provide for the printing industry. It is necessary to improve the quality of printed conductive lines, while maximizing electrical performance. The gravure printing method should be utilized to address these issues. A number of changes will need to be implemented within gravure printing in order for it to provide the most efficient platform for the production of printed electronics. This paper will note key points of needed improvements and provide possible solutions for problems, using examples of experiments that have already been conducted. In the end, it will evaluate how these changes can be accomplished, and it will evaluate the potential success gravure has in the future of printed electronic production.

Research Methodology Gravure printing is the preferred method for the production of printed electronics today. The gravure printing technique possesses the following characteristics, which are vital to the manufacturing of printed electronics:

47 1. Fast throughput 2. Long print runs 3. Uniformity and consistency 4. Scalability The gravure printing method has advantages over competing methods, such as flexography and screen-printing. These advantages include speed, pattern thickness, and simplicity of the process itself. There are significantly less variables to control within the gravure press, providing more uniformity in print appearance. While the gravure printing method is a popular platform for printed electronic manufacturing, certain elements in the process must change in order to ensure continued development of the printed electronics industry. Manufacturers must improve several factors, such as “fabricating smooth, narrow and straight lines” (Sung). Conductive ink properties must be examined in order to evaluate the most effective characteristics. Substrate properties will also be examined in terms of quality and efficiency. In the following, these needed improvements will be discussed in detail. Smooth Lines In order to manufacture functional printed electronic devices, it is essential that smooth, straight lines be produced. Smooth lines are crucial because “they allow the dielectric layer above the conductive layer to be as thin as possible” (Sung). This allows the device to operate at a lower voltage. Narrow lines are also vital in that they assist in scaling interconnects, fabricating high-Q inductors, and improving the overall circuit performance (Sung).

Print Quality and Electrical Efficiency of Printed Electronics • Shannon Ling

48 Unfortunately, gravure is at a disadvantage in this area, for its cell components make it difficult to produce consistent straight lines, and smaller details are especially hard to construct. The main problem derives from the electromechanical engraving method, which often creates serrated edges in a printed line and causes issues in ink film uniformity. While this engraving method helps in graphics printing of tonality, it causes problems when producing printed electronics. For printing electronics, the production of uniform ink film is necessary to create smooth lines. Dr. Keif, a Graphic Communication professor at California Polytechnic State University, San Luis Obispo explains this more extensively in the article, “Major Trends in Gravure Printed Electronics”, where he states, “with electromechanical engraving, these [printing electronics] would require a consistent cell depth, which is not typically how it’s done” (Clark). He also notes that this is solely a problem for electromechanical engraving, since cell depth can be controlled with other forms of engraving, such as acid etching or laser engraving. The printing of smooth lines is not solely associated with the production of printed electronics, but with the production of gravure printed products as a whole. One solution that could assist with the formation of smooth lines is through the process of electrodepositing grooved gravure plates onto substrates in which a photoresist pattern has been formed (Hagberg). After electro-deposition, the plate should be peeled from the substrate. The depth of grooves in the plate can be controlled and the grooves themselves have a smooth surface. This process possesses advantages that assist in producing higher quality details and narrower line widths than exist-

49 ing processes. Manufacturing grooved gravure printing plates is one solution that could benefit the production of smooth, straight lines essential to printed electronics manufacturing. Printed electronics have stricter requirements than typical printed applications. Interestingly, printed electronic production requires a slightly different patterning than what is seen in gravure printing today because it must be closer together, and no printing method has fully been able to support this. This issue alone supports the fact that the printed electronics industry is still developing, and gravure must evolve in order to remain the preferred printing technique for this industry. Straighter, Narrower Lines: A Solution The results of an experiment involving gravure printed electronics was published in the article, “Scaling and Optimization of Gravure-Printed Silver Nanoparticle Lines for Printer Electronics” by graduate students at University of California, Berkeley. The experiment determined that the most efficient way to produce smooth, straight lines is by placing individual cells close together. The experiment proved that individual drops of ink placed closer together formed the straightest conductive lines. The ratio of cell spacing and cell width should also be managed and it is important that the ratio remains between 1.06 μm and 1.40 μm. While past studies focused on larger cell sizes, this experiment provided innovative ideas to produce optimal conductive lines. The main focus of the experiment involved varying the size of the cell, and

Print Quality and Electrical Efficiency of Printed Electronics â&#x20AC;˘ Shannon Ling

50 utilizing the smallest possible cell size available. It also considered the importance of ink viscosity in this process. Conductive Ink Properties & Their Effect on Quality and Electrical Performance Conductive inks consist of entirely different particles than traditional ink and it is important to examine how these inks should be printed within gravure printing technologies. The following paragraphs will discuss ink properties, including ink chemistry, viscosity, solvent evaporation rate, drying, and how these properties affect the print quality of gravure printed electronics. To begin, common ingredients of conductive inks should be listed, in order to differentiate conductive ink properties from traditional ink properties. These ingredients include pigment, dispersants, resins or polymers, defoamers, wetting agents, pH modifiers, biocide and bacteriosis (Cho). The ink itself is extremely sensitive in comparison to non-conductive inks, and rigorous lab work and chemistry continues to develop new and improved inks (Hartman). Gravure Conductive Inks & Print Quality Several types of printed electronic inks exist today. The most popular examples include conductive inks, semi-conductive ink, and dialectic ink. These inks contain metal particles, which make them electrically conductive. Conductivity can also be achieved by â&#x20AC;&#x153;using polymers that exhibit electronics conductivity in a suitable solventâ&#x20AC;? (Hrehorova). Traditionally, many of these inks were screen printed, but gravure printing offers several advantages over screen-printing.

51 The gravure printing process is currently focusing on conductive inks such as solvent-based polyaniline inks and hyrdrocarbon resin based inks. These inks are more pressure resistant than traditional inks and offer higher printing resolution and thickness. There are many ink properties that affect print quality, an important one being viscocity. Aspects that affect viscosity are the angle of the doctor blade and the silicon oil content. Research conducted at the Microelectronics Laboratory in Finland has determined that when the doctor blade’s pressure is high and at a low in speed, the ink will perform at a higher viscosity. Their research proved that hydrocarbon inks transfer to the surface more efficiently than traditional ethyl cellulose inks. It was also determined that an increase in solid contents in the ink had a positive effect on electric conductivity and on the amount of ink transferred. In fact, the ink from the grooves was picked up three times more than traditionally used ethyl cellulose based inks. Surface Tension of Inks The inks surface tension affects spreading and wetting properties, depending on the substrate. When conductive inks are printed, time is a crucial factor, since the overall film quality will be affected by the faster escape of co-solvents from the conductive ink film. Surface tension gradients must be controlled, because the “fast evaporation of alcohols can cause printing defects such as discontinuity of printed lines” (Hrehorova). In order to improve gravure’s production of printed electronics and minimize these issues, the rate of evaporation for solvents needs to be controlled at a consistent rate.

Print Quality and Electrical Efficiency of Printed Electronics • Shannon Ling

52 Conductive Inks on Flexible Substrates Conductive ink that is commonly used for flexible surfaces in gravure is called electrically conductive adhesives, or ECA. It is composed of silver, gold, copper, nickel, and platinum, Carbon is often used as filler. The silver particles are essential for ECA because they provide low resistance and a thin oxide layer. These silver particles can be spherical or flake shaped. Flake shaped silver particles offer better conductive traces, however, they must also be “packed in the organic binder material without melting the silver flakes” (Pudas). These silver particles are coated by either polymer or static acid, which prevent them from gathering in clumps. Unfortunately these coatings hinder electronic conductivity. To improve their conductivity, the silver flakes must also be coated low-melting point metals. An experiment conducted in Microelectronics and Materials Physic Laboratories in Oulo, Finland, compared the quality of ECA inks printed on both paper and plastic film. A table demonstrated in Figure 3 shows substrates rated by roughness that were used in the experiment. The goal of the experiment was to analyze the characteristics of the gravure printing process and its ability to print conductive ink. A Dektak 3D instrument was used to analyze the printed samples and their surfaces. Their resistance was measured with a HP3457A multimeter (Pudas). In addition, a folder tester was built for tests. The experiment was then set up as follows: The printed antenna’s signal strength and efficiency was evaluated. The results found the most successful gra-

53 vure printed electronics had a higher volatile solvent content and a slightly lower viscosity. Ink Viscosity and Surface Uniformity Earlier in this paper, the discussion of cell spacing concluded that when cells are placed closer together, conductive lines print straighter and narrower. While this is dependent on the cell spacing, it is also dependent on ink viscosity. The key in manufacturing printed electronics is to produce smooth lines at a maximum thickness. Problems arise when ink viscosity is too low; printed lines are too thin and the overall image sharpness decreases. In contrast, when ink viscosity is to high, the printed line has a lack of uniformity. Lack of uniformity is just as detrimental as a thin ink film. Dr. Xiaoying Rong, a Graphic Communication professor at California Polytechnic State University in San Luis Obispo, has noted a concern for ink surface uniformity issues with the gravure printing process. Because gravure ink is composed of cells, the surface of the ink has “peaks and valleys” (Clark). For printed electronics, a thick and uniform surface is important for electrons to flow. Luckily, the gravure printing method is able to lay down thicker ink films, decreasing electrical resistance. The problem that remains is that these “peaks and valleys” hinder the creation of a uniform surface; the lower the surface uniformity, the higher the electrical resistance. So while gravure is capable of producing a thick ink film, it cannot maximize quality and efficiency within printed electronic production until it is capable of producing uniform surfaces as well.

Print Quality and Electrical Efficiency of Printed Electronics â&#x20AC;˘ Shannon Ling

54 Substrates It is also important to evaluate which substrates provide the best platform for printed electronics. Substrate properties are a large component in the production of printed electronics. Controlling and testing the correct ink properties is important in terms of quality and resolution, and selecting the best substrate properties is directly correlated with this. Traditional gravure substrates are flexible, printed either in a web-fed or roll- to roll process. However, printed electronics require more dimensional stability in their substrates. Dimensional stability is especially important in order to produce the highest possible electrical performance. More dimensional stability also provides better resolution and registration. PET foil vs. Paper Measuring the surface smoothness of the substrate is an integral part of the printing electronics process. The rougher the surface, the less uniform the ink film will be. In order to use the gravure method to print the highest quality electronics, one must consider the substrate requirements for printed electronics. In comparison to graphics printing, printed electronics require â&#x20AC;&#x153;homogenous, pinhole-free layers to ensure the functionality of the polymeric layersâ&#x20AC;? (Trnovec). The figure below demonstrates some of these key differences in the needs of printed electronics compared to graphics printing. PET foil is an excellent candidate for the production of printed electronics. Its surface is extremely smooth, especially in comparison to other substrates. High smoothness level allows for good electrical barrier

55 properties. While PET foil may seem like an obvious substrate choice based on the advantages it provides, it also has disadvantages, including price. Its temperature resistance is also too low. Therefore, paper is a common substrate choice for printed electronics, for its

Ink transfer versus solid content percentage of ink.

â&#x20AC;&#x153;advantages lie in its broad application areas, price, processability, register accuracy, and environmental friendlinessâ&#x20AC;? (Trnovec). In order for paper to be properly readied for conductive ink transmission, it must be coated. There are several different materials that the

Print Quality and Electrical Efficiency of Printed Electronics â&#x20AC;˘ Shannon Ling

56 paper can be coated with. Some examples include kaolin portions and portions of CaC03. The goal is for the coating to help the surface of paper resemble the surface of the PET foil. Unfortunately, paper roughness is still a problem after coating, and gravure will need to compensate for this issue in order to improve overall electrical performance. Gravure Printing and Glass: A New Idea The gravure printing method must also adopt new substrates in order to compete in printed electronic industry. Glass is an example of a substrate that is already used in the electronic industry. Glass provides an excellent substrate for printed electronics for the following reasons: it has high thermo-mechanical stability, high surface quality, high chemical resistance, and provides an effective barrier to oxygen and moisture (Hrevoka). One would think that screen-printing would be the preferred method to print on glass, however, extensive research is being done on how gravure can properly print on glass substrates. The Printing Process: Glass An experiment conducted at the Center for Advancement of Printed Electronics at Western Michigan University, specifically tests how gravure technology can be used to print on glass. A cylinder was specifically made for the experiment; this cylinder was indirectly laser engraved, and its cell depth was set at approximately 30 Îźm. In order to properly print on the rigid glass substrate, a sheet-fed gravure proofer, the Prufbau Rotogravure Printability Tester, was brought in from Germany. The article notes the printing process as follows:

57 1. The glass substrate is soaked in de-ionized water and isopropyl alcohol. 2. An impression blanket covers the flat, rigid carrier. 3. The carrier is fed between the back-up roller and rotating printing cylinder. 4. The nip is created by contact between substrate and cylinder. 5. The cylinder pushes the substrate through the nip. 6. The ink is then transferred from the engraved cells onto the glass (Hrehorova). Problems from this experiment included varying line widths and ink film thickness. To solve one of these issues, the cells could be spaced closer together to produce narrower line lengths. Because glass provided such an excellent platform for electrical performance, gravure needs to evaluate ways it can improve printing on glass substrates. If perfected, gravure printing on glass substrates will provide a valuable manufacturing technique for the future of printed electronics.

Results & Discussion It is especially important to note that the projected growth of the printed electronics market is expected to go from 16 billion dollars this year to 76.3 billion dollars in the next 10 years (Rivkin). However, for gravure to capture this projected growth, the experiments and research developments analyzed in this paper indicate that several changes must be implemented for this to occur. The main areas for improvement in terms of quality and efficiency include:

Print Quality and Electrical Efficiency of Printed Electronics â&#x20AC;˘ Shannon Ling

58 1. Producing straighter, smoother lines 2. Controlling and optimizing key ink properties 3. Analyzing which substrates should be optimized. This paper has highlighted a number of solutions that can assist in improving these areas. For example, one solution suggests moving cells closer together to produce narrower, straighter lines. Conductive inks have also been discussed; especially ink properties such as viscosity and evaporation rates. These properties were examined in relation to their ability to enhance electric conductivity and improve print quality. Lastly, different substrate options, such as paper and foil, were analyzed to determine the best substrate for printed electronic manufacturing. It was noted that in order to improve the quality of printed electronic production, the importance of smoothness and flexibility must be taken into account. A study on how gravure can expand its market share to print on glass substrates was also explained in depth. The possibility to print on glass is a new advancement that could expand the gravure printing industry.

Concluding Remarks Based on the research findings in this paper, it can be concluded that the gravure printing method offers several advantages compared to other printing methods. These advantages include speed, ink film thickness, and consistency. The gravure method must constantly strive to improve quality and efficiency within the printed electronics industry. The problems highlighted in this research paper should be improved upon in order for gravure to remain the preferred printing method for printed electronics production.

59 Requirements

Printing

Electronics

Functional Material

Pigment, colorant

Functional

Resolution of Structures

> 20 μm

<< 20 μm

± 5 μm

< 5 μm

Layer thickness

≈ 1 μm

30 ... 300 nm

Layer homogeneity

Not important

Very important

Adherence of layers

Important

Solvent

Optimized for price

Optimized for function

Chemical cleanness

Not important

Very important

Visual properties

Very important

Not important

Electronic properties

Not important

Very important

Requirements of printed electronics versus tradtional graphics printing.

References Cho, Giyun. Public Speaker. 2014. Clark, Donna. (2014). Major trends in gravure printed electronics. Graphic Communication Department California Polytechnic State University San Luis Obispo, 1-29. [DigitalCommons] Hagberg, Juha, Pudas, Marko, Leppavuori, Seppo, Elsey, Ken, & Logan, Allison. (2001). Gravure offset development for fine line thick film currents. Microelec- tronics International, 18(3), 32-35. [GoogleScholar]

Print Quality and Electrical Efficiency of Printed Electronics • Shannon Ling

60 Hartman, Alexandra. Public Speaker. 2014. Hrehorova, Erika, Rebro, Marian, Pekarovicova, Bazuin, Bradley, Rannganathan, Sean Garner,…Boudreau, Robert. (2011). Gravure printing of conductive inks on glass substrates for applications in printed electronics, Journal of Display Tech- nology, 7, 6, 318324. [IEEEExplore] Hrehorova, Erika, Pekarovicova, Alexandra, & Fleming, Paul. (2006). Gravure printability of conducting polymer inks. Digital Fabrication, 107-110 . [Google- Scholar] Pudas, Marko, Hagberg, Juha, & Leppavuori, Seppo. (2009). Printing param- eters and ink components affecting ultra-fine-line gravure-offset printing for electronics applications. Journal of the European Ceramic Society, 24, 10-11, 2943-2950. [ScienceDirect] Pudas, Marko, Halonen, Granat, Paivi, & Vahakangas, Jouko. (2005). Gravure printing of conductive particulate polymer inks on flexible substrates, Process in Organic Coatings, 54, 1, 310-316. [ScienceDirect] Rivkin, Faye. (2013) Soaring growth projected for printed electronic market. Industry Market Trends. Subramanian, Vivek, Chang, Josephine, Vornbrock, Alejandro, Huang, Daniel, Jagannathan, Lakshmi, Lio, Frank… Zhang, Qintao. (2008). Printed electronics for low-coast electronic systems: Technology status and application development, Solid-State Circuits Conference, 34, 17-24. [IEEEExplore] Sung, Donovan, Vornbrock, Alejandro, & Subramanian, Vivek. (2011). Scaling and optimization of gravure printed nanoparticle lines for printed electronics, IEEE Transactions on Components and Packaging Technologies, 33, 1, 105-113. [IEEEExplore] Trnovec, B., M. Stanel, U. Hahn, A.C. Hubler, H. Kempa, R. Sangl, & M. Forster. (2009). Coated paper for printed electronics. Professional Papermaking, 48-51.

SHANNON LING I am a 4th year Graphic Communication student at Cal Poly, originally from Sugar Land, Texas. My concentration is Digital Reproduction Technology, and it is my dream to pursue a career in graphic design. Over the summer, I interned at Kiosk Creative in Novato, CA. At my internship I worked as a graphic designer and had the opportunity to work with companies such as The University of Texas Online System. I also worked on local campaigns and developed designs for several nonprofit organizations. After graduation, I want to travel to Thailand and Bali. When I return, I plan to start my career in the Bay Area.

POTENTIAL AREAS OF GROWTH IN ROTOGRAVURE BY HANNAH STOMBLER-LEVINE

66 68 77 81 85 87

Introduction

Research Methodology

Results & Discussion

Concluding Remarks

References

Author Biography

Abstract In recent years, print has faced increased pressure to produce economical products with shorter runs and turnaround times. Although many traditional print processes have modified their business models to remain profitable in todayâ&#x20AC;&#x2122;s changing times, gravure has faced further challenges due to the makeready process and long-run product model. Rotogravure printing, or gravure, is defined as web-fed printing that utilizes a cylinder to transfer an image directly to a variety of flexible and semi-rigid substrates. Gravure is admired around the world for its high-quality image reproduction, capabilities for consistent quality, varying ink-film thicknesses, and even continuous images. However, due to the laborious makeready process required to prepare cylinders, gravure is traditionally utilized for products requiring longer or repeated runs. Furthermore, with the decline of print in the past decade, pressure to economically produce short-run products has increased for companies and converters alike. Gravure can remain a top competitor by moving into segments such as the thriving market of printed electronics, as well as utilizing competitive modifications within the print process such as laser engraving and sleeves. Additionally, areas of potential growth also lie within hybrid or combination printing, which could help bridge the gap between flexography and gravure. By adopting alternative methods of production and application, the market segment of gravure could directly address the challenges brought forth by the digital revolution, and begin creating a new model of expansion.

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

Introduction Industry leaders and consumers alike have declared print is dead, referring to the traditional printed market segments, (Gomez 2009). According to a recent article by The Commentator, published August 12, 2013, “In under 10 years, print advertising revenue in the US has fallen from $44.9 billion to $18.9 billion,” (Gravedigger 2013). Although print will never die in the capacity by which our presses will stop running, the historical market of print, particularly gravure and other longer run processes have been forced to re-evaluate their businesses and adopt new technologies in order to compete. Gravure, being one of the oldest and most mature printing processes, dating back to around 100 AD, and with bragging rights of successfully achieving the first computer to plate transfer, has faced tough competition to produce economical products in shorter runs and with decreased turnaround times. Additionally, industry leaders have also faced pressure to find new areas of potential growth outside of their traditional niches to combat the digital revolution and keep gravure printing vibrant and continuous, just like its printed product. With pressure on industry leaders to find new technologies that expand into the gravure product market, many have looked at printed electronics as the future of gravure. According to John Jay Jacobs’ thesis, “An Investigation of Fundamental Competencies for Printed Electronics”, presented in May 2010 by the Graduate School of Clemson, “The potential for printed electronics applications markets is projected to grow as large as $300 billion USD by the year 2015.

67 Other than packaging, printed electronics has the highest growth potential of any of the printing industry segments today,â&#x20AC;? (Jacobs 2010). Currently, printed electronics are already printed using various printing processes, however gravure is a strong competitor due to its ability to print the highest resolutions, achieve superior conductivity and print varying ink film thick-nesses while maintaining functional properties of its electronic applications. Furthermore, although gravure already has a large market segment in organic light emitting diodes (OLEDâ&#x20AC;&#x2122;s) for displays and lighting, and Radio Frequency Identification Tags (RFID) for intelligent packaging and consumer applications, it also shows great potential for transistors, circuits and interconnects for a potential future market segment. Another area of expansion within the gravure market is increasing adoption of competitive modifications within the print process. One proposed solution to combat the long makeready preparation time is to directly modify steps within the process and explore options such as laser engraving instead of electromechanical engraving, and sleeves instead of steel cylinders. Currently electromechanical engraving only reaches speeds of about 9,600 cells per second, while laser engraving can reach nearly 32,000 cells per second, with added benefits such as smoother edges and greater ink transfer to the substrate. Another modification to the makeready process is the use of sleeve technology, which replaces the use of 500 lb. steel cylinders for 10-15 lb. sleeves. Sleeves greatly reduce makeready time, allow the mandrel to be reused, decrease shipping and transportation costs, and actually lower the cost of the cylinder itself due to a material source reduction.

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

68 The last print modification proposed is to utilize combination or ‘hybrid’ printing to bridge the gap between flexography and gravure, reaping benefits of both processes to create the most attractive printing process and deliver brilliant, unparalleled results. ‘Hybrid’, or combination printing, utilizes an additional printing unit, usually flexography (or lithography), to offer benefits of other printing processes that gravure often struggles to compete with. By utilizing combination printing, many of the undesirable aspects associated with gravure such as economically difficult longer runs, or cylinder modifications and version customization will be a thing of the past, and customers will be able to utilize brilliant color and high quality prints while achieving cost-effective prints. By shifting the focus from traditional selling agents of gravure and moving into areas such as Printed Electronics, as well as exploring modifications within the printing process such as laser engraving instead of electromechanical engraving, sleeves instead of steel cylinders, and hybrid or combination printing to bridge the gap between flexography and gravure, the market segment of Rotogravure could not only show stability, but growth and expansion in future years to come.

Research Methodology Printed Electronics One area with tremendous potential for proving the relevancy and need for gravure printing in todays’ declining market of traditional print is printed electronics. In a recent feature on printed electronics in the Spring 2013 issue of GAA Magazine, GAA Magazine

69 commented that, “It is not widely known, but since the first-mass producible electronic circuitry was developed in the early 1900’s, the printing and electronics industries have been intertwined. In fact, the first patent [...] for electronic circuitry was British patent 4681, led in 1903 by Albert Parker Hanson for ‘printed’ circuits on paper created additively through the deposition of metal powder in a medium of conductive ink and adhesive,” (GAA 2013). Since 1903, printed electronics has grown to a multi-billion dollar market, with forecasts to exceed $300 billion USD by 2025, (VTT 2012). Today, it is nearly impossible to look around a room, an office or even answer your cell phone, without utilizing the work of printed electronics. Printed electronics is the application of conductive, or semi-conductive electronic components onto a variety of substrates by the means of conductive inks via a printing process. Currently, nearly all other printing processes compete in the printed electronics market place in one way or another, but with varying competitive advantages. However the advantages of gravure for printed electronics are nearly endless, including the ability to print on a wide variety of flexible and rigid substrates, direct transfer of ink, roll-toroll capabilities, long run-length durability, and the ability to achieve varying ink film thicknesses while maintaining conductivity. In terms of printed electronics applications, gravure has also already shown success in applications such as organic light emitting diodes (OLED) for displays and lighting, as well as the ability to produce radio frequency identification tags (RFID) for intelligent packaging and consumer applications. Additionally, one potential market that holds a great expansion opportunity for gravure is transistors, circuits and

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

interconnects, which are crucial for nearly all electronic devices and would greatly strengthen gravure’s involvement within the printed electronic industry. Considering that gravure already has the technology and ability to produce a variety of printed electronic applications, research and development is extremely important to propel further applications to sustain economical practices and competitive applications to help consumers and manufacturers support the use of gravure for printed electronics. Although in recent years the media and market research attention on printed electronics was minimal for high volume applications, VTT at University of Finland has recently observed various materials suppliers showing increasing activity in testing and application development (VTT 2012). This is particularly important because, according to Dr. Anoop Menon, senior research scientist for Add-Vision, Inc., a leading developer of organic light-emitting polymer display technology, “Add-Vision, Inc., and its partners are developing pilot scale equipment specifically for printed electronics [that will] enable large manufacturers to build pilot scale production facilities. There will [soon be] be large publishing firms entering the printed electronics world [that will want] to use existing infrastructure to create electronic applications within traditional printing,” (Savastano 2013). When facilities and businesses are ready to expand their services to printed electronics, there will be research and technology allowing them to use their existing infrastructure to do so. Instead of having to switch to digital presses in order to stay economically fit, press operators will be able to utilize this data to save money and space, all while staying contemporary and desirable.

71 In the recent article, “Gravure Makes Inroads in Printed Electronics”, by David Savastano published in Printed Electronics Now Magazine, Savastano explains why gravure will likely become the leader in the printed electronics industry, commenting that, “Gravure allows the ability to print fine resolution, which is key to conductivity, and offers high ink transfer. [Gravure,] [is] also a high-speed process, which makes it ideal for high volume applications,” (Savastano 2013). Although other printing methods such as offset lithography and screen-printing are still competitive in terms of resolution, gravure is clearly capable of producing the finest resolution, which in turn supports higher conductivity and higher ink transfer (VTT 2012). Another reason Gravure excels above competing processes is in its’ ability to apply a high volume of ink. Unlike screen, for example, gravure is able to transfer high volumes of ink, even at very fine resolutions. By doing so, gravure manages to achieve a third dimension of depth whilst maintaining fine resolution that preserves conductivity and functionality. Overall, one of the most promising areas of growth for gravure is printed electronics, which has been projected to grow from nearly $16 billion this year to $76.8 billion in the next 10 years, according to a recent report by IDTechEx (IMT 2013). Although Printed Electronics has tough competition within the market place, gravure is a strong competitor based on its ability to print varying ink film thicknesses, achieve great depths that are still conductive and flexible, and its ability to print at high speeds and at extremely high resolutions, all lending to high conductivity for various applications.

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

Laser Engraving, Sleeve Technology and Combination or Hybrid Printing Traditionally, two of the main disadvantages associated with gravure printing are long makereadies and long press runs. However, with a drastic shift in job lengths, gravure has faced tough competition to compete with processes that have redesigned their business models to produce economical methods of printing short run products with quicker turnaround times. According to The Gravure Report, published by Ink World Magazine, “The key challenge to gravure is the belief that it cannot be a viable short-run printing process, a serious concern considering that printers are facing increased demands for shorter, more localized runs,” (IWM 2002). However, at a recent visit to the R.R. Donnelley plant in Reno, Nevada, supervisor Bill Saabt explains that in the midst of the digital revolution, R.R. Donnelley and many other gravure press facilities faced challenges competing with short-run jobs. Saabt, however, explains that, “In order to compete [R.R. Donneley and other plants] had to develop a way to lower run lengths while remaining competitive. [They] have remained profitable even at a 10,000 run length, which traditionally was not thought possible,” (Saabt 2013). Like many gravure facilities, R.R. Donnelley has done this by exploring various print modifications within the printing process, all with expectations of lowering makeready times to save time and money, while also increasing competition from suppliers, customers and other converters. Modifications such as laser engraving, sleeves instead of directly engraved cylinders, and combination printing are

73 all potential modifications within the printing process capable of lending to the overall growth and attractiveness of Rotogravure. The most time consuming component of makeready is cylinder preparation, or engraving. There are three different gravure cylinder engraving methods: electromechanical engraving, direct laser engraving, and laser exposing or chemical etching. Currently, electromechanical engraving is the most commonly used engraving method, however it can only produce speeds of around 9,600 cells per second. Furthermore, when using electromechanical engraving, cells are confined to fixed ratios defined by the geometry of cell angles specified by the pulse of the diamond stylus, thus producing ragged edges. In contrast, direct laser engraving eliminates the use for a mechanical stylus, and employs speeds of up to 32,000 cells per second. With direct laser engraving, cell dimension is able to produce a free selection of cells, producing smoother edges, and a greater optimization of ink transfer to the substrate (Hrehorova 2007). By using laser engraving, cylinders are engraved at much greater speeds, drastically cutting makeready times and saving customers and converters money and time. However, possibly more importantly, by switching to laser engraving, individual cells will be engraved without fixed ratios optimizing ink transfer to the substrates, creating smoother edges and overall higher quality products. Another competitive modification and potential area of growth within gravure printing is the use of sleeves instead of directly engraved

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

74 cylinders. Traditionally, in gravure the main image carrier is typically a steel cylinder with a thin copper coating applied by electroplating, with the exception of cylinders that accept a further layer of zinc for direct laser engraving (for durability and reflection purposes.) The steel cylinders weigh several hundred pounds, thus incurring steep costs for shipping, transportation, storage and movement in-and-out of the press. One technology that helps save time, money and efficiency in all steps of the printing process is the use of lightweight sleeves in place of steel cylinders. According to Claus Larsen, Market Support Manager for Nipeter, a press manufacturer in Slagelse, Denmark, “Sleeves are a major area of interest with gravure [because] gravure printing presses used to be dominated by large and heavy cylinders that had to be transported around in a factory or between factories. Today, however, these heavy cylinders have been replaced by sleeve technology, which makes transportation and changeover much easier and operator friendly,” (Sartor 2007). With traditional gravure cylinders, press operators had to take out the entire cylinder and shaft assembly in order to put in the new one. However, with gravure sleeves, they simply slide them onto the mandrel shaft. Sleeves also offer ergonomic benefits as well, helping to lower shipping and transportation costs, as well as storage and press setup. Traditional steel cylinders need to be stored upright and are extremely expensive to ship and transport. With sleeves, however, there are systems that allow for stacking in lightweight, yet durable boxes. These systems are compact, saving space and money, yet still deliver

75 cylinders with a fraction of the shipping and transportation costs. Furthermore, an added benefit of reduced weight is a decreased environmental impact, which is increasingly attractive to consumers and suppliers in todayâ&#x20AC;&#x2122;s marketplace. Gravure sleeves also provide

Projected growth in the printed electronics industry.

a cost-effective alternative to traditional sleeves, with 20-30% less downtime when transporting cylinders between presses and locations. Additionally, engraving times are greatly reduced, since no old images need to be removed, and converters donâ&#x20AC;&#x2122;t need to wait for bases to be shipped. Instead, sleeves are simply stripped from the

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

76 mandrel, and a new one is applied. Aside from decreased manual labor, shipping costs and transportation costs, sleeves also dramatically reduce the cost of the actual gravure cylinder. Although a number of press facilities already utilize sleeve technology, by increasing the number of press facilities that do, and raising awareness to the facilities that do not have access to sleeve technology, gravure make-ready could drastically be reduced, and overall turnaround time on products could be decreased as well, saving time and money. The last area of potential growth within gravure is the use of combination or ‘hybrid’ printing to close the gap and reap the benefits of both gravure and flexography, making gravure the most attractive possible choice to consumers, and converters alike. With increased competition in the marketplace, consumer product companies are demanding more from converters to deliver products in shorter turnaround times, depict more vibrant colors, and provide more customization than ever before. Gravure has experienced challenges due to long makeready times, and difficult cylinder corrections, however with the emergence of combination printing, converters are able to bring key benefits from both printing processes and amalgamate all the advantages into one printed product, delivering unparalleled quality that grabs the attention of any consumer. Additionally, because gravure is most cost effective at longer-runs, ‘hybrid’ or combination printing is often utilized for products that will be used for repeated runs, but may have personalized information that could only be printed utilizing short-run options, such as flexography or lithography. By combining the two processes, print facilities

77 can save time and money without having to re-engrave cylinders for short-run customized information. According to Steve Leiben, sales manager for Matik North America, â&#x20AC;&#x153;The ability to slide a flexo station into any station on the press offers tremendous flexibility. Sliding [additional stations] in when needed allows converters to offer new things to their customers. They have another weapon in their sales arsenal.â&#x20AC;? (Sartor 2007). By utilizing combination printing, many of the undesirable aspects associated with gravure such as expensive press changes and customization will become a thing of the past, and customers will be able to utilize brilliant color and high quality prints while achieving cost-effective products.

Results & Discussion In order to ensure that gravure remains a top competitor amongst consumers, converters, suppliers and industry leaders, the adoption of both new applications and competitive modifications within the print process need to be integrated into a new model to compete with other shorter-run printing processes in the market today. The first area with tremendous potential for growth that should be adopted into the gravure printing industry is printed electronics. Printed electronics is projected to expand as much as $300 billion USD by the year 2015, and holds the highest growth potential of any other printing industry segment today be- sides packaging (Jacobs 2010). Currently, gravure has already shown success in applications such as organic light emitting diodes (OLED) and radio frequency identification tags (RFID). In addition, one potential market that holds a great expansion opportunity are transistors, circuits and interconnects, which are crucial to nearly all electronic devices and would

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

78 greatly strengthen gravure’s involvement within the printed electronics industry. Gravure continues to remain a strong competitor in the printed electronics industry for a multitude of reasons including its ability to print fine resolutions, high ink transfer, roll-toroll capabilities, means to print on both flexible and semi-rigid substrates, and its ability to print varying ink-film thicknesses while still achieving conductivity. According to John Lettow, president of Vorbeck Materials, a graphene-based conductive gravure ink manufacturer, “For manufacturers, the main advantage of gravure [for printed electronics] are line speed and ink usage, which is generally less than screen printing. Gravure can print very thin layers while maintaining high conductivity,” (Savastano 2013). One aspect of the overall process that was evaluated was competitive modifications that could potentially reduce makeready, making gravure a more attractive option regardless of run length. The first competitive print modification was the transition from electromechanical engraving to direct laser engraving. Currently, electromechanical engraving is the most widely used engraving method, however it can only reach speeds of around 9,600 cells per second. Additionally, electromechanically engraved cells are confined by fixed aspect ratios defined by the geometry of the diamond stylus, thus producing ragged edges. On the other hand, direct laser engraving attains speeds of 32,000 cells per second, and allows for a free selection of cell dimensions, unrestrained by fixed ratios. By utilizing free dimensions of cells, a greater ink transfer is achieved and a higher-quality image is produced. By using direct laser engraving, cylinders are engraved at much greater speeds, drastically reducing

79 makeready times and saving customers and converters money and time, thus making the gravure printing process more attractive. The next print modification and potential area of growth within gravure printing is the use of sleeves in place of traditional steel cylinders. Steel cylinders typically weigh nearly 500 lbs, but lightweight sleeves, weighing only 10-15 lbs, can save time, money and makeready. In the past, extremely heavy, cumbersome cylinders that required multiple press operators and automated machinery for maneuvering dominated cylinder technology. Sleeves, however, offer lightweight technology that reduce downtime by 20-30% and allow a single press operator to simply slide them on-and-off the mandrel shaft when needed. Furthermore, this allows the mandrel to be reused. With traditional steel cylinders, cylinders were stored upright and were extremely expensive to ship. Sleeves are stored in lightweight boxes, which can be stacked to save space, and can be shipped for a fraction of the cost, offering decreased environmental impact and increased shipping and transportations savings. Lastly, aside from decreased manual labor, shipping and transportation costs, sleeves also reduce the cost of the actual gravure cylinder due to a dramatic material source reduction. The last area of potential growth analyzed within the gravure printing process is the use of combination or ‘hybrid’ printing. Combination or ‘hybrid’ printing works to close the gaps between gravure and flexography, delivering superior results and making gravure the most attractive possible choice to consumers and converters alike. As discussed, increased demand to produce the highest-quality results in the

Potential Areas of Growth in Rotogravure â&#x20AC;˘ Hannah Stombler-Levine

Varying cell dimensions of electromechanical and direct laser engraved cells.

shortest turnaround time has hit gravure much harder than other printing processes. Most constricting in this case, however, is the long makereadies, which have challenged gravure to find alternative methods of reducing run-lengths and overall turnaround times. Fortunately, combination printing allows converters to deliver the same unparalleled quality that consumers are demanding from gravure converters, with various aspects of flexography or lithography such as personalization or multiple version changes.

81 According to Steve Leiben, sales manager for Matik North America, “The ability to slide a flexo station into any station on the press offers tremendous flexibility. Sliding [additional stations] in when needed allows converters to offer new things to their customers - unique or new constructions. They have another weapon in their sales arsenal.” (Sartor 2007). By utilizing combination printing, many of the undesirable aspects associated with gravure such as economically difficult longer runs will become a thing of the past, and customers will be able to utilize brilliant color and high quality prints while achieving cost-effective products. When asked whether the demand for combination printing has increased in the past few years for his facility, Claus Larsen, Market Support Manager for Nipeter, a press manufacturer in Slagelse, Denmark responded, “On a year-to-year basis, Nilpeter is experiencing more and more demand for incorporating one or more gravure stations across the range of our presses, and we do not expect this upward trend to change anytime soon,” (Sartor 2007).

Concluding Remarks In light of the digital revolution, gravure has experienced increased pressures to produce economical products in shorter runs and with shorter turnaround times. Various traditional print processes have already modified their business models to remain profitable in today’s changing times, however gravure has faced further challenges due to laborious makeready and expensive and time-consuming cylinder preparation. Luckily, industry leaders have accepted the challenge of discovering new areas containing potential growth outside of traditional gravure printing in hopes of combatting the digital revolution and keeping gravure printing a viable option for the

Potential Areas of Growth in Rotogravure â&#x20AC;˘ Hannah Stombler-Levine

Electromechically engraved cells above show much more geometric, confined and rigid edges, while laser engraved cells show much smoother edges and transitions.

future. Printed electronics, direct laser engraving in place of electromechanical engraving, sleeve technology to eliminate cumbersome steel cylinders, and combination or â&#x20AC;&#x2DC;hybridâ&#x20AC;&#x2122; printing are all areas that show potential to help pave the way to a more secure future for the gravure printing industry.

83 However, of all proposed solutions discussed, though all viable options, the most promising areas of potential growth based on research are printed electronics and combination printing. As mentioned previously, printed electronics holds the highest growth potential of any printing industry segment aside from packaging, which will never cease to exist. Furthermore, printed electronics is projected to grow $300 Billion USD in the next 15 years, which is no surprised based on our need for constant electronic stimuli, both externally and internally. Although many of us are not aware of it, printed electronics are commonly used in medical applications with implementations such as glucose test strips and in our favorite iPhone running apps in the form of accelerometers. As the wearable technology movement continues to increase, the printed electronics industry becomes both impulsive, yet crucial. On the other hand, packaging is the highest growing segment of all printing, which also makes it the most competitive. With increased competition brought on by the overall decline in print, anything that differentiates printed products from one another is extremely attractive to converters and consumers alike. For this reason, combination printing is likely to expand in future years to come. Gravure is often veered away from due to long makereadies and its longer-run model, however with combination printing, converters are able to offer the superior quality and brilliant reproduction of gravure, with the customizable and short-run qualities provided by a flexo unit addition. According to Larsen, combination printing has been increasing every

Potential Areas of Growth in Rotogravure â&#x20AC;˘ Hannah Stombler-Levine

year since the introduction to his facility in 2007, and Nipeter, a press manufacture in Denmark, expects the trend to continue in future years to come (Sartor 2007). Although gravure may be fighting against all odds when it comes to the digital revolution, by shifting focus away from the traditional gravure process into the printed electronics industry, as well as adopting a new model allowing for competitive modifications within the printing process, the future of gravure could not only show stability, but growth and expansion in future years to come.

References Direct laser engraved cells. Digital image. Janoshka. Web. Dreher, Martin, Dr. “Flexo vs. Gravure in Packaging Printing.” European Rotogravure Association. DFTA-TZ, 11-12 Oct. 2006. Web. 12 Nov. 2013. Electromechanically engraved cells. Digital image. Janoshka. Web. Fuente Vornbrock, Alejandro D. “Roll Printed Electronics: Development and Scaling of Gravure Printing Techniques.” University of Berkeley Electrical Engineering. Fall 2009. Web. 2 Nov. 2013. Gomez, Jeff. Print Is Dead: Books in Our Digital Age. Basingstoke: Palgrave Macmillan, 2009. Print. Gravedigger. “The Stark Reality of Print Media’s Decline.” The Commentator. S.M.A.R, 12 Aug. 2013. Web. 1 Nov. 2013. Hrehorova, Erika, and Ramesh-Chandra Kattumenu. “Evaluation of Gravure Print Forms for Printed Electronics.” GravurEzine. March 2007. Web. 11 Nov. 2013. <http://www.gravureexchange.com/gravurezine/0702-ezine/hrehorova.htm> Jacobs, John J., Samuel T. Ingram, Dr., Liam O’Hara, Dr., and Chip Tonkin, Mr. An Investigation of Fun- damental Competencies for Printed Electronics. Thesis. The Graduate School of Clemson University, 2010. South Carolina: Graduate School of Clemson University, Graphic Communications, 2010. Print. Kurssi, Painettavan E. Introduction to Printed Electronics and Intelligence.University of Oulu VTT Tech- nical Research Centre of Finland Business from Technology. University of Oulu, 27 Mar. 2012. Web. 9 Oct. 2013. <http://www.ee.oulu.fi/research/opintotoimisto/WikinLiitetiedostot/Liitetiedostot/PrintEl2012.pdf>

Potential Areas of Growth in Rotogravure • Hannah Stombler-Levine

86 Projected Market Growth. Digital image. California.ca Electronics. Web. Sartor, Michelle. “This Printing Process, Though Not Very Common in Narrow Web, Offers Certain Benefits for Converters. - See More At: Http://shows.labelandnarrowweb.com/articles/20 07/10/gravure-printing#sthash. 5JPz22gK.dpuf.” Label & Narrow Web. Label & Narrow Web Rodman Publishing, Oct. 2007. Web. 23 Nov. 2013. Savastano, David. “Gravure Makes Inroads in Printed Electronics - Printed Electronics Now.” Printed Electronics Now Magazine. Printed Electronics Now Magazine Rodman Media, 2013. Web. 1 Nov. 2013. < h tt p : / / w w w. p r i n t e d e l e c t r o n i c s n ow. c o m / a r t i c l e s / 2 011 / 0 2 / g r av u r e - m a ke s - i n roads-in-printed-electronics>. Savastano, David. “The Gravure Report: Gravure’s Positions in Publication and Packaging Printing Of- fers a Look at How the Printing Industry Is Faring.” Ink World Magazine. Ink World Magazine, May 2009. Web. 22 Oct. 2013. <http://www.inkworldmagazine.com/ articles/2009/05/the-gravure-report>.

HANNAH STOMBLERLEVINE I am a soon-to-be graduate concentrating in Design Reproduction Technology, with a minor in Industrial Technology Packaging. After college I hope to find work in the food industry where I can further my passion for food photography, web design, and magazine publication. My dream job includes working at Bon Appétit, designing magazine layouts or working on their web content… but I would also settle for official taste tester! Over the past few years, I have developed my personal brand FIVEforks, which helps promote honest food photography without the use of harmful additives. I hope to soon publish a cookbook with my family. When I’m not photographing food, I enjoy spending time in my hometown Davis, CA. with my two sisters and English lab, Homer.

THE FUTURE OF GRAVURE IN THE PRINTED ELECTRONICS INDUSTRY BY SARAH PILEGARD

92 93 104 105 107 109

Introduction

Research Methodology

Results & Discussion

Concluding Remarks

References

Author Biography

Abstract The printing industry is always looking for new and innovative ways to continue producing quality printed products. The gravure industry is no exception, but with the rise in demand for printed electronics the gravure industry has great potential to thrive in several new markets opened by printed electronics. Gravure printing is a process that has the necessary capabilities to meet the high standards for several types of printed electronics. These electronics include printed film transistors, resistors, biosensors, semiconductors, and conductive inks. Printed transistors and resistors have proven to be very effective and functional for small applications such as organic light emitting diode (OLED) displays or functions in low-end packaging or advertising. Printed biosensors have proven to be useful in research to develop electrochemical biosensors for the medical field, used for detecting nano sizes of bio and chemical species. Conductive inks have been successful in printing on flexible substrates to create function circuits used in organic field-effect transistors and light emitting circuits. All of these processes are complex and unique requiring high quality manufacturing techniques. Gravure printing has the ability with the correct usage of ink viscosity, rheology, and printing techniques to accomplish the production of functional printed electronics and drive the further development of this industry. This paper will discuss all of these things and will use secondary research to support the ideas presented.

92 The Future of Gravure in the Printed Electronics Industry â&#x20AC;˘ Sarah Pilegard

Introduction With the technology age thriving and the rise in popularity of eBooks, e-zines, and e-newspapers, it is difficult to predict how the gravure printing industry will survive; however, there is a new demand for printed electronics, and gravure printing is the perfect candidate to thrive from this emerging industry. The market for printed electronics is growing increasingly popular and is all the more plausible thanks to successful experimentation in the field. There are a variety of applications and devices produced with conductive inks, printed transistors and sensors that encompass this growing field. Due to the high level of accuracy, quality, and rigid specifications needed to produce small functional printed electronics, gravure printing provides the perfect technique to achieve this while also providing a more energy efficient form of production. The demand for printed electronics is expanding due to the versatility and functionality of the printing industry. Cost savings and large area coverage primarily drive the market for printed electronics, and due to direct printing and additive processes it is preferable to the photolithographic alternative (Ghaffarzadeh). While the gravure printing industry needs a new avenue to expand business and provide growth, a variety of newly emerging printed electronic technologies need a reliable printing technique that is efficient, accurate, and precise enough to handle their complexity and delicacy.

93 This would promote growth for the gravure industry and would also provide a manufacturing process that is more energy and time efficient while still producing quality products. Gravure printing has the potential to successfully print and produce renewable photovoltaic electronics, printed flexible indium-tin-oxide (ITO) films, polymer based light emitting electrochemical cells (LECs), thin film transistors, and conductive ink circuits.

Research Methodology Manufacturing Printed Electronics With Gravure Printing Due to the printing standards required for printed electronics and conductive inks, gravure printing is the optimum technology to further the emerging printed electronics industry (Casatelli). There are several factors of gravure printing provide the accuracy needed for conductive inks. Gravureâ&#x20AC;&#x2122;s ability to print with consistency and high resolution contribute to making it the best production method for conductive inks (Peterson). Screen-printing is the most common technique used for producing printed electronics; other techniques such as offset and inkjet have also been used. However, gravure is more efficient at producing high through put than screen-printing, also it prints with less picking than offset, and at a better quality than inkjet (Gable) (Peterson). According to the text Organic Electronics II, â&#x20AC;&#x153;To date, the vast majority of printed electronics demonstrations have been in the area of printed wiring boards, membrane switches, and printed passive components for applications such as RFID tags and touch screens. In these applications, printing has been deployed both in research

The Future of Gravure in the Printed Electronics Industry • Sarah Pilegard

94 and production.” This book also states that, “for printed electronics, gravure does offer some advantages,” these include its ability to print fine lines and fine spaces for printed electronics patterns not only that but its film thickness control allows for production of high-quality thin films that are suitable for use in thin-film electronic devices. (Klauk) However, there are factors to be aware of when printing gravure, including serrated line edges and line edge roughness. The process of gravure uses of small individual ink cells to release the ink onto the substrate, therefore the size of the cells is important when printing conductive inks to maintain functioning circuits. Another factor that affects the width and thickness uniformity of ink is the viscosity. When the ink is too viscous it will not glide smoothly together to create fine lines, but if the ink viscosity is too low then it will spread too much and not produce the desired line width. (Klauk) However, according to the article, The Compromises of Printing Organic Electronics: A Case Study of Gravure-Printed Light-Emitting Electrochemical Cells, the performance of gravure printing technologies can be adjusted to fit the rigid specifications of printed electronics well. This case study states, “gravure printing is a promising option for the high-throughput of optoelectronic devices. It is suitable for a wide variety of solvents and it allows for high printing speeds. Moreover its lateral resolution on the micrometer scale makes it particularly suitable for the production of organic field-effect transistors (OLEDS) or solar cells.” This case study further explains the steps of manufacturing gravure printed OLED. In the steps, they used functional ink

95 with a viscosity between 10 and 100 mPa s and one of two drying processes: surface demodulation or film drying (Hernandez-Sosa). However, with the use of conductive inks it is important to keep in mind the difference in properties. As mentioned before, viscosity is a key factor in the ink formulation. Due to the uneven thickness produced by the ink from hydrodynamic instabilities, a printing pattern is created in the printing direction called viscous fingering (Hernandez-Sosa). This means because of the viscosity, the ink tends to run when printed creating streaks in the product, it was discovered, that this can be adjusted by the poly (methyl methacrylate) PMMA or polymer solid content of the ink. The inks being used are made of “poly (methyl meth acrylate) (PMMA) and tetrabutylammonium tetrafluroborate (TBABF) as the polymer solid electrolyte (PSE), and a poly (phenylvinylene) derivative commonly known as “Super Yellow” (SY) as the emitting semiconductor material,” (Hernandez-Sosa). This means that the conductive inks have a polymer solid electrolyte component, which provides the semiconductor material for the printed circuitry. With higher amounts of the polymer solid electrolytes, the viscous fingering pattern is minimized. However, it is important to keep the viscosity and shear properties of the ink in mind since polymers and electrolytes are formulated in the ink creating different properties than normally dealt with in gravure printing. The positive results of this case study proved that a polymer-based light emitting electrochemical cell (LEC) system could use ink formulations for a given printing technique without changing its chemical

The Future of Gravure in the Printed Electronics Industry â&#x20AC;˘ Sarah Pilegard

96 composition. The printed LEC was able to illuminate to ca. 200 cd m-2 at 10 V, a Von of 6.5 V and a shelf lifetime of over six months, which makes them acceptable for low-end applications like packaging or advertisements (Hernandez-Sosa). This study also proves that adjusting the viscosity can compensate for the serrated edges typically produced when printing gravure, and functional circuitry is still effectively produced with this method of printing. In the following section a case study proves that that with viscosity considerations and experiments the serration of gravure printing has minimal effect on printed semiconductors. Gravure Printed Semiconductors In a study done at the VIT Technical Research Centre of Finland, they tested the capabilities of a low voltage, gravure printed transistor using commercial polymer materials and pre-patterned metal electrodes. Results showed potential for making low cost, large area electronics possible due to the success of creating gravure printed transistors and inverters that can operate at low voltages (Hassinen). They printed eight different line densities on PET substrates with pre-patterned gold electrodes, and the transistors, once dried, were connected together in a diode connected load configuration, which formed inverter circuits (Hassinen). The thickness of the printed semiconductor was 10-80 nm, which was proportional to the transfer volume of the gravure cells, and even though the semiconductor film quality was poor, the transistors still worked well (Hassinen). They compared the functionality of these printed transistors to spin coated transistors and the results are shown in the graph below.

97 As stated in the report, â&#x20AC;&#x153;the performance of the printed transistor is similar or better than the spin coated reference transistor with roughly the same dimensions,â&#x20AC;? from these results they concluded that gravureâ&#x20AC;&#x2122;s tendency to produce serrated edges and channels did not affect the performance of the transistor (Hassinen). Their results can be seen below, the spin-coated transistor is represented by the red curve and the printed transistor is represented by the blue curve.

The relationship between gate source voltage and current.

The Future of Gravure in the Printed Electronics Industry • Sarah Pilegard

98 Their findings show that gravure printing can successfully produce functioning printed electronics without the concern of serrating the fine lines needed for production. It will still be important to regulate viscosity and other printing techniques as mentioned in previous sections, but gravure has great potential in this field due to the quality pieces it produces. Thin Film Transistors Thin film transistors are not a new phenomenon, but new ways to produce and use them are quickly increasing their demand. They are commonly found in flat panel displays (Howard). An article by Mark Vruno called, Tech Update: RFID/NFC Printed Electronics, explains the role gravure printing has in this new field, he states that, “… gravure printing of electronics is of significant interest due to its ability to print high-resolution features and thin layers having uniform morphology.” Not only does gravure provide a way to successfully produce printed electronics on thin films it provides a more cost and time effective approach to production. Due to the cost effectiveness of printing thin film transistors and conductive inks compared to traditional formation of electronic patterned layers, interest in producing functional printed electronics is growing. Conventional electronics systems are made using three to more than a dozen subtractive patterned layers. The process begins with first depositing a blanket layer of material (conductor, semiconductor, or dielectric) on a wafer, coating that layer with photo-resist, secondly the photo-resist is exposed using lithographic techniques, then after it is developed the layer is etched through the exposed

99 regions of the pattern, and the photo-resist is stripped, and then in the final step the wafer is cleaned. Comparatively, printing a conductor layer using nano-particle ink or a conductive polymer would involve two steps: the patterned layer is printed using specified conductive ink, then the ink is dried and sintered (Klauk). With less process time there is less energy being used and also less time to manufacture and produce the final product. This is with the consideration that the make-ready costs and time for gravure would be compensated due to the high throughput produced. Printing these thin film electronic devices obviously reduces production time and is more energy efficient. Further research and studies have also shown that gravure provides the required level of accuracy and continuity required. For example, in Dr. Khasha Ghaffarzadeh’s article Where is the printed thin film transistor technology now, he states, “Transistors are a vital piece of technology in the emerging toolkit of printed electronic components.” He further explains that transistors are very complex and require, “intricate patterning or layer-to-layer registration.” With gravure printing, this required level of accuracy is achievable. An article by Zhihua Chen called, A high-mobility electron-transporting polymer for printed transistors, records studies done and tests performed to prove the effectiveness of using gravure to print thin film resistors (TFTs). Results showed that “top-gate, bottom-contact (TGBC) thin film transistors with a ~1 [micro] m-thick PMMA or D2200 dielectric layer can be fabricated with high fidelity.” In other

The Future of Gravure in the Printed Electronics Industry â&#x20AC;˘ Sarah Pilegard

100 words, gravure printing proved to be capable of printing the required accuracy and quality needed for the dielectric layer on TFTs with a thickness of roughly 0.00003937 inches. For gravure to be able to produce functional products at that quality is phenomenal and opens the doors for all the possibilities gravure can have in this industry. Because of its ability to print so accurately on thin films, gravure can also be used to print indium-tin-oxide (ITO) films, which are beneficial in a variety of flexible electronics such as organic photovoltaics, liquid crystal displays, organic light-emitting diodes, touch screens, and biosensors (Alsaid). The following section will further explore how gravure printing can provide energy efficient alternatives with other printed electronic technology. Grauvre Printing Of Conductive Inks And Electronic Displays Gravure printing with conductive inks provides an energy efficient alternative to amorphous silicon based transistors, which could improve the entire manufacturing process of liquid crystal displays (LCDs), electrophoretic displays (EPDs), and organic field-effect transistors (OFETs). All of these flexible circuits provide the inner workings for displays in cameras, monitors, calculators etc. Being able to produce those components on flexible films with gravure printing can provide space saving components for a variety of electronic devices. Amorphous silicon based transistors are typically used as the switching and amplifying parts in modern electronics and require high-vacuum, high-temperatures manufacturing processes. Formulating inks

101 from organic semiconductors provides an alternative to the traditional amorphous silicon-based transistors. Printing with conductive inks would allow for, “large-area, high-throughput, low-temperature fabrication of organic field-effect transistors (OFETs).” This creates cheaper flexible circuitry and the lower temperatures allow for the use of plastic substrates (Klauk). This makes production and fabrication more cost effective and time efficient. OFETs are being used as individual pixel switches in circuitry, which are placed in small-sized electrophoretic displays (EPDs) and are also found in liquid crystal displays (LCDs) and organic light emitting diode displays (OLED) – the transistors provide current to the emitting diode component (Klauk). EPDs and LCDs require different semiconductor mobility, which affects how advantageous the OFETs are within the devices. With EPDs the, “pixels are reflective to ambient light, which allows the pixel transistor to occupy the majority of the area underneath the pixel…enabling more current to be delivered…resulting in lower mobility specifications required from the semiconductor.” Also since EDPs only need power to charge the pixel and storage capacitor, the duty cycle load of the transistor is reduced which extends its lifetime. However, large-size LCDs require higher resolution displays and need more power than the small OFETs can provide (Klauk). There is a lot of room for more research and improvement in the production of printed LCDs but gravure printing has great potential for printed EDPs, which is a growing market as the demand for smaller

The Future of Gravure in the Printed Electronics Industry • Sarah Pilegard

102 more flexible EDPs increases due to the increases in demand for smaller more compact electronic devices and displays. Gravure also has the potential to break into many other fields within printed electronics and has already proven to be beneficial in some including printed biosensors. Gravure Printed Electrochemical Biosensors There has been an increase in demand for printed electrochemical biosensors and with the success of gravure printed electronics, the gravure industry has the potential to tap into the agricultural, environmental, and medical industries through this market. There is a high demand for electrochemical biosensors in several industries, as stated in a report by scholars from Western Michigan University, “The development of reliable, miniaturized, accurate and cost effective electrochemical sensors that detects various biochemicals is essential for the agricultural, environmental and medical industries,” (Reddy). Their work with printing electrochemical sensors in, SciVerse ScienceDirect: Gravure Printed Electrochemical Biosensor, demonstrates how they were able to successfully print on a flexible polyethylene terephthalate (PET) substrate using sliver nano particle based ink containing interdigitated electrodes (IDE’s) (Reddy). The sensor consisted of eight pairs of electrodes, each electrode measuring, “8600 μm length, 200 μm width and 200 μm electrode spacing,” (Reddy). They used Western Michigan University’s web-fed Cerutti Gravure Press because it is known to produce at high quality,

103

Gravure printed biosensors, printed on flexible substrates.

high speed, and uses low viscosity inks, the biosensors printed can be seen in the images above. (Reddy). From this study they were able to conclude that there is great potential for printed, â&#x20AC;&#x153;electrochemical biosensors to distinguish among the pico, nano, and micro level concentrations of various bio/chemical species,â&#x20AC;? (Reddy). With their success in demonstrating not only the capability to successfully print electrodes on flexible substrates, but also the success in the functionality of those sensors this shows the potential for further success. Gravure printing technologies have the potential to break into the agriculture, environmental, and medical industries by producing this much-needed technology.

104 The Future of Gravure in the Printed Electronics Industry • Sarah Pilegard

Results & Discussion Gravure shows a lot of potential for being the best printing process to produce a variety of functional printed electronics. After looking at the effects of ink properties, and printing factors such as fine line reproduction, gravure still has the advantage of high throughput and quality production. The success seen in several case studies for the printing of thin film transistors, resistors, biosensors, semiconductors, and conductive inks prove that gravure has the ability to break into several new product markets. The demand for printed electronics is ever increasing as the demand for more technology that is smaller, more mobile, and convenient increases. Printed electronics are also becoming more popular in packaging and advertising. According to the text, Organic Electronics II, “…various groups have been able to demonstrate devices with performance approaching or even exceeding that of amorphous silicon [a commonly used material for small electric circuits], by exploiting the simplicity and additive process capabilities of printing techniques including…gravure printing…we see how the field of printing, including its physics, technology, rheology, materials science, and device integration, can be used to drive the development of printed electronics.” With this in mind, gravure-printing capabilities have proven to be supportive of the printed electronics industry and the two industries can benefit each other significantly.

105

Printing of thin film electronics on gravure press.

Concluding Remarks Because of its ability to produce quality functional printed electronics, gravure is the perfect candidate to be a leader in printed electronics production methods. Gravure printing can provide the accuracy and complexity required and the demand for printed electronics can benefit and grow the gravure industry. Also, by producing printed electronics that require less energy during manufacturing

The Future of Gravure in the Printed Electronics Industry â&#x20AC;˘ Sarah Pilegard

106 and require less voltage to function, gravure printing helps promote environmentally conscious products. As mentioned in a previous section gravure printing is an additive process instead of the traditional subtractive method and is comparatively more cost effective, time efficient, and environmentally friendly. Therefore, gravure printing proves to be a very effective process to drive the development of printed electronics.

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References Alsaid, D.A; Rebrosova, E.; Joyce, M.; Rebros, M.; Atashbar, M.Z.; Bazuin, B., “Gravure Printing of ITO Transparent Electrodes for Applications in Flexible Electronics,” Display Technology, Journal of, vol. 8, no. 7, pp. 391, 396, July 2012. Casatelli, Linda M. “GAA’s IPP Conference Addresses Printers’ Questions.” Printing News Oct 23 2006: 1-7. ProQuest. 6 Oct. 2014. Chen, Zhihua, et al. “A high-mobility electron-transporting polymer for printed transistors.” Nature 457.7230 (2009): 679+. Academic OneFile. Web. 17 Oct. 2014. Cover image source: Quattelbaum, Rebecca. “PrintoCent Pilot Factory inaguration presenting new Coatema concept,” Coatema. March 19, 2012. Retrieved from: <http:// www.coatema.de/eng/presse_news/meldungen/2012_03_19_news.php?navanchor=1310078>. Gable, T., & Goin, R. (2002). Printing preferences: Offset vs. gravure. Catalog Age, 19(7), 67. Retrieved from <http://ezproxy.lib.calpoly.edu/login?url=http://search.proquest.com/ docview/200613956?accountid=10362>. Ghaffarzadeh, Dr. Khasha. Where is the printed thin film transistor technology now? Printed Electronics World: IDTechEx. 25 January 2013. < http://www.printed electronicsworld.com/articles/where-is-the-printed-thin-film-transistor-technologynow-00005115.asp?sessionid=1>. Hernandez-Sosa, Gerardo, Serpil Tekoglu, Sebastian Stolz, Ralph Eckstein, Claudia Teusch, Jannik Trapp, Uli Lemmer, Manuel Hamburger, and Norman Mechau. The Compromises of Printing Organic Electronics: A Case Study of Gravure-Printed Light-Emitting Electrochemical Cells. Advanced Materials. MaterialsViews.com. Publisher: Wiley-VHC Verlag GmbH & Co. KGaA, Weinheim. 2014. Jo, Jeongdai, et al. “Development of a gravure offset printing system for the printing electrodes of flat panel display.” Thin Solid Films 518.12 (2010): 3355+. Academic OneFile. Web. 6 Oct. 2014.

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108 Klauk, Hagen, Editor. Organic Electronics II: More Materials and Applications. Pgs. 3-7, 183-187, 239, 241-251. Wiley-VCH Verlag GmbH & Co. KGaA. 2012. Petersen, D. (1994). Gravure gets going. American Printer, 212(6), 38. Retrieved from http:// ezproxy.lib.calpoly.edu/login?url=http://search.proquest.com/docview/212717156?accountid=10362. “Printing Equipment for Printed Electronics 2014-2025.” PR Newswire Sep 18 2014 ProQuest. 6 Oct. 2014. Reddy, A.S.G., B.B. Narakathu, M.Z. Atashbar, M. Rebros, E. Rebrosova, M.K. Joyce. Gravure Printed Electrochemical Biosensor. SciVerse Science Direct. Procedia Engineering. Elsevier Ltd. September 4-7, 2011. <www.sciencedirect.com>. Vruno, Mark. “Printed Electronics/RFID 2012.” MyPrintResource.com (2012) ProQuest. 6 Oct. 2014. Vruno, Mark. “Tech Update: RFID/NFC and Printed Electronics.” MyPrintResource.com (2013) ProQuest. 6 Oct. 2014.

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SARAH PILEGARD I am a third year Graphic Communication major at Cal Poly, with a concentration in Graphics for Packaging, and a minor in Packaging. I have been involved with TAGA for the past three years, and am currently the club treasurer and college council representative. I really enjoy how being part of this industry inspires creativity and ingenuity, and I hope to pursue a career in food packaging design. In my free time, I like to create multimedia art projects and experiment in the kitchen with my own recipes. I grew up in Fresno, California, which makes me really appreciate the beautiful weather and beaches of San Luis Obispo County.

PRINTED ELECTRONICS APPLICATIONS FOR PUBLICATIONS BY ABEL MARQUEZ

114 121 125 123 132 135

Introduction

Research Methodology

Results & Discussion

Concluding Remarks

References

Author Biography

113

Abstract The purpose of this research was to demonstrate that the printing industry can potentially benefit from the incorporation of printed electronics into the publications and packaging fields. Taking advantage of this technology would attract more consumers, especially younger generations who are immersed in the digital world and feel more engaged with products that offer user interactivity. Experts in the field were interviewed to get information and feedback about the project. Also, a survey was conducted. Cal Poly students, from different areas and departments were included to see if they would be interested in subscribing or buying a magazine that incorporates printed electronics and then, determine if this project is possible considering the budget, plan, resources, information available, and the level of acceptance based on the survey results. The analysis of the results indicated that the printing industry can potentially benefit by the incorporation of printed electronics in the publications and packaging fields. This project would involve more people who specialize in different majors rather than Graphic Communication like Physics, Business, Editorial, etc. Also, many students expressed that they would be willing to purchase or subscribe to a magazine that incorporates printed electronics if the content is relevant to them and the cost is not expensive.

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Introduction

Printed Electronics Applications for Publications â&#x20AC;˘ Abel Marquez

Statement of the Problem: The Printing Industry is Struggling The advancement of the digital technologies and mobile markets makes it difficult for the printing industry to compete. Without innovation and a strategy for the future, the industry is in a risky situation. It has been said that the printing industry is dying because of the digital revolution, and to continue the industry needs innovation. One area of innovation is â&#x20AC;&#x153;printed electronicsâ&#x20AC;?. What people like about digital technologies is their interactivity and user friendliness, so the printing industry should consider user interactivity as a relevant aspect to attract more customers. This technology can enhance the user experience and interactivity in the forms of packaging, intelligent labels, flexible materials, and publications. By using semi- conductive inks, a retail display can light up or track customer movements, a food package can indicate the temperature of the product, a publication can emit sounds when pressing a printed button, a medical label can indicate when a prescription has to be taken. Significance of the Problem: Targeting a Young Audience It has been said that the younger generations are immersed in the digital world. Therefore, it is important to focus on the people that are being targeted already by the companies and markets. The challenge will be to convince young people that printed products, like a magazine, can also be fun, interactive, and informative as a web page. By finding ways that enhance the finished product, through printed electronics, young customers can be attracted to and make

115 decisions that will increase their use of printed products. With the help of something measurable, like a magazine that incorporates printed electronics, a young audience can be reached and the results can be analyzed for future projects. Interest in the Problem: A New Field to be Explored in Graphic Communication One of the reasons I am really interested in this topic is because printed electronics is a new field in Graphic Communication and the printing industry. I strongly believe that it can offer a lot of potential for publications, packaging, and other kinds of products and services that will help to recover this hurt industry in part by the emerging technologies in the digital arena, and by the crisis in the global economy. I am also interested because I am considering pursuing the Masterâ&#x20AC;&#x2122;s degree that Cal Poly will offer in Printed Electronics. Literature Review In the field of printing, there is a new area developing called â&#x20AC;&#x153;printed electronicsâ&#x20AC;?. This technology can enhance the user experience and interactivity in packaging, intelligent labels, flexible materials, and publications. With the advancement of the digital and the mobile technologies, the printing industry is struggling in the market place. Younger generations are immersed in the digital world and the printing industry is trying to survive and be competitive. Therefore, with the incorporation of new technologies like printed electronics in the publications and packaging markets, younger consumers could find in printed products a new interactive experience. This could impact the printing industry in a positive way.

Printed Electronics Applications for Publications • Abel Marquez

116 First, it is important to define the term printed electronics. This term refers to the process of integrating semi-conductive inks made from chemicals like polymers with different kinds of substrates in order to get an interactive experience with printed products. According to Sridhar, Blaudeck, and Baumann (2014), printed electronics refers to the application of printing techniques, both conventional and digital, to fabricate electronic structures, devices and circuits, no matter which functional materials (ink) and substrates are used. “The only prerequisite is that the functional material must be processable from the liquid phase.” These products go from smart packaging to interactive displays and publications. According to Scott (2006), the majority of the chemicals used in the printed electronics field are polymers. “They include the conductive polymers polyaniline, polyacetylene, and polythiophenes. Polymer films used as substrates for products such as printed circuits include pre-treated versions of polyester, polyethylene, and polyethylene terephthalate (PET).” Moreover, it is also important to talk about the characteristics of printed electronics. Printed electronics is a new way of printing conductive materials that at the end can enhance the final product. By using semi-conductive inks, a retail display can light up or track customer movements, a food package can indicate the temperature of the product, a publication can emit sounds when pressing a printed button, a medical label can indicate when a prescription has to be taken. Printed electronics offer many advantages to the printing industry. Among these advantages is the possibility of creating printed

117 intelligent packaging, brand awareness, smart cards, and brand protection. It can also be applied in the medical field by telling the customer when a certain prescription has to be taken. Harrop (2007) states that Radio Frequency Identification (RFID) will replace 10 trillion barcodes yearly, mimicking the history of barcodes which were originally applied as labels - now 90% are directly printed. “Medical tablets will be supplied in packages that monitor which pill you took when, that prompt you by sound and vision - possibly even vibration - and show instructions in large scrolling fonts. There is even one experimental package that calls out ‘not now’ if you touch it at the wrong time of day.” Harrop also talks about smart packaging and indicates that signage and packaging in supermarkets will be in moving color, the signage being changeable at the press of button in some remote office. It is also important to talk about the historical aspect of printed electronics, in order to understand the factors that contributed to this field. The printed electronics industry started in the 1920s with the incorporation of graphite as one of the main components of conductive inks in order to transfer energy through the different manufactured circuits. Ken Gilleo declares in this article The Real Printed Electronics the following: “In the 1920s, circuit pioneers printed conductive inks made with graphite and, later, powdered metals such as copper and silver. But a visionary dream of many who worked on printing conductors was in prim all of the electronics, including components. Primed passive devices, like resistors and capacitors, were relatively simple, and

Printed Electronics Applications for Publications • Abel Marquez

118 methods were developed during WWII. The idea of printing active devices was not even a consideration until the advent of solid-state electronics. Priming active electronics components would prove to be a greater challenge that would require special and complex materials, and never priming processes tor commercial viability” (Gilleo, 2007). Even though this technology is still in development, there are many tangible applications that are giving positive results based on years of research and experimentation. Hariharan (2006) declares that printed electronics potential includes displays, backplanes, radio frequency identification (RFID) antennas and tags, computer memory, sensors, greeting cards, toys and smart cards. And this can offer many opportunities in the manufacturing side for companies dedicated to produce inks, flexible substrates, chemicals, circuits, etc. “The growth of printable electronics should create new opportunities for chemical companies at the bottom of the supply chain such as those that can offer inks (metallic and organic), solvents, adhesives and plastic substrates. Some of the companies servicing the market are Cabot, Dow Corning, Ferro, DuPont, HC Starck, Merck KGaA and DuPont Teijin Films.” One of the most utilized methods for printed electronics is inkjet printing. This is because of the lower cost, the high resolution in terms of graphics, and the capability of printing in a variety of substrates. According to Schroeter (2007), inkjet printing has many advantages, including high resolution (80- to 100-μm lines), flexibility, relatively low cost, and compatibility with almost any type of

119 substrate. “Printed electronics is driving further equipment development, as the newest inkjet heads may be capable of 20-μm feature sizes, which would greatly expand the use of inkjet technology in electronics.” Another printing method that has become popular for printed electronics is screen printing. Screen printing can be applied to many kinds of substrates and its flexibility is what makes this method unique for products that incorporate printed electronics. “Screen printing can be used with a variety of substrates. It’s also possible to deposit thick films in a single pass. On the other hand, it cannot be used to deposit extremely thin layers. It was once considered a very low- resolution technique, but state-of-the-art screens can achieve features as small as 40 μm, with sharper edges than ink-jet” (Schroeter, 2007). The potential markets for printed electronics are in different fields like packaging, brand awareness, display screens, smart textiles, brand protection, smart cards, medical, solar cells, and publications. This new technology also creates opportunities for traditional industries like printing. Nilsson (2012) declares that recent advances in printed electronics, radio frequency identification tag production, and standardization of communication protocols are factors that increase the design freedom for new applications. “As in all new fields, the first products are expected to appear in the high-cost segment attracting early adopters in the form of niche products.”This new field of printed electronics has growth expectations because

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Printed Electronics Applications for Publications • Abel Marquez

younger generations demand a more interactive experience. They are immersed in the digital world and printed electronics can satisfy those demands for more interactive printed products. Klaus G. Schroeter states the following: “Next, just about everything can get smarter, as combinations of printed sensors, logic, memory, and communication appear in products that haven’t included electronics. Applications include RFID tags for inventory control, interactive product packaging that talks or plays games, smart food packaging that changes the use-by date, drug packaging that monitors and communicates patient compliance, and clothing that monitors the wearer’s vital signs and helps regulate body temperature. Printed electronics could provide power as well. Flexible, high-efficiency photovoltaics could power mobile devices and commercial/residential power, while lightweight photovoltaics and thin- film batteries could power printed electronic devices” (Schroeter, 2007). The challenge for the printing industry is to integrate printed electronics with effective marketing campaigns, quality designs and products, and new media platforms. According to Harrop (2007), if you put together a random selection of industries - electronics, chemicals, plastics land printing - a new technology emerges that is now seeing the first fruits of a long gestation period. “Printed electronics is without doubt the technology of the future, a technology that some pundits predict could even dwarf the success of the silicon chip.” With the implementation of new technologies, the printing industry can be competitive in the market place.

121 Even though the printed electronics field has a long history of research and experimentation, it is still in development and can bring opportunities to the printing industry. By incorporating this new technology to printed products like packaging or publications, a new enhanced experience can be brought to younger generations who are definitely seeking for a more interactive visual experience. For this reason, it is important for the printing industry to consider this technology as the motor that could revitalize its permanence and competitiveness in the future.

Research Methodology The purpose of this research was to demonstrate that the printing industry can potentially benefit from the incorporation of printed electronics into the publications and packaging fields. Taking advantage of this technology would attract more consumers, especially younger generations who are immersed in the digital world and feel more engaged with products that offer user interactivity. The objective of this research was to: Analyze the pros and cons of having a monthly magazine in Cal Poly, from a business perspective, that incorporates printed electronics and then test the results by analyzing studentâ&#x20AC;&#x2122;s response though a survey. Evaluate the effectiveness of using printed electronics for packaging and publications by interviewing experts in this field and analyzing the revenue of different companies that incorporate this technology in their products.

Printed Electronics Applications for Publications â&#x20AC;˘ Abel Marquez

122 The targeted audience was Cal Poly students, male and female, with an age range between 18 and 34 years old. The plan was to work on an experiment to determine the effectiveness of the use of printed electronics in the publications field. This was accomplished by creating a fictitious prototype of a monthly magazine that incorporated printed electronics. This magazine contained information for Cal Poly students, like upcoming events on campus and the community, articles written by faculty members and students, a detailed directory of all the different colleges and departments, useful tips and information, suggestions for entertainment. In addition, experts in the field were interviewed to get information and feedback about the project. Faculty members from the Graphic Communication department: Xiaoying Rong, Malcolm Keif, and Colleen Twomey were interviewed. Experts in the field who participated in the seminars during the International Printing Week, here at Cal Poly were contacted. Among them were Tim Luong, National Sales Engineer with Ceradrop MGI Group, and Philip Lazo, director of Innovation for RockTenn Merchandising Displays. Questions related to printed electronics, packaging, and publications were asked. These questions were asked to find an effective way to incorporate printed electronics in a monthly publication. Another question was related to the possibility to run a test here at Cal Poly considering the necessary equipment, materials, labor, and logistics behind this project. Moreover, the questions were intended to know the cost of working on a project like this, the possibility to generate some revenue based on other examples from companies that are

123 already focusing in printed electronics, and the necessary implementations to create a prototype like this, run it, test it, and evaluate its effectiveness. Finally, a survey was conducted. Cal Poly students, from different areas and departments were included to see if they would be interested in subscribing or buying a magazine that incorporates printed electronics and then, determine if this project is possible considering the budget, plan, resources, information available, and the level of acceptance based on the survey results.

Results & Discussion First of all, some questions were asked to experts in the field to evaluate the effectiveness of using printed electronics for publications. The intent of these interviews was to analyze the pros and cons of having a Cal Poly monthly magazine that incorporates printed electronics, from the technical and business perspectives. The same questions were asked to all the participants, but other questions were different during the process of these interviews. The first question was: What can be an effective way to incorporate printed electronics in a publication like a monthly magazine? Professor Xiaoying Rong emphasized the importance of having enough advertisement in the magazine that could offer some interactivity by using printed electronics. â&#x20AC;&#x153;Usually, very often there is advertisement in the magazine or could be a feature article and those are the ones that most reasonable that you can put some interactive in the magazineâ&#x20AC;? (Rong, Appendix).

Printed Electronics Applications for Publications • Abel Marquez

124 Also, Professor Rong explained that another consideration for an effective incorporation of printed electronics is the power supply. “You have to have power associated with that so every time you are doing something it has to be power related and figure out how you incorporate your power into the entire design” (Rong, Appendix). It is necessary to know if high power or low power is required and also the AC/DC difference is imperative for the success of its functionality. Professor Malcolm Keif said that solving the power equation was crucial to find the effective way to incorporate printed electronics in a publication. He mentioned that he worked on a magazine that required low power and was called Canvas. “So the technology we used for Canvas magazine was electro chromic which is a very low power requirement technology so you can cause things to appear or to, you know, disappear” (Keif, Appendix). The term electro chromic is basically related to change the colors of a specific surface through the use of some sort of electric energy. In this case it is more difficult to come out with a magazine that would require high power, said professor Keif. “The one thing that is difficult is that a lot of the real luminescing technologies, the technologies that actually emit photons they usually require high power requirements” (Keif, Appendix). Professor Colleen Twomey emphasized the importance of having a cool factor in order to attract younger generations and that can be done with printed electronics. “There is got to be a cool factor but research chose and you might be able to find this through your literature reviews at the library that if someone is viewing something that

125 is interactive they are going to be staring at it longer therefore interacting with that brand” (Twomey, Appendix). Professor Twomey said that by adding printed electronics to a publication it would increase the duration of the readers looking at an advertisement or article to 11 times longer than a regular printed piece. Philip Lazo, director of Innovation for RockTenn Merchandising Displays, suggested that the best way to accomplish an effective incorporation of printed electronics in a magazine was to integrate an NFC tag in the publication and then link it to a digital media experience. “NFC Tags are an application of RFID technology. Unlike most RFID, which makes an effort to give a long reading range, NFC deliberately limits this range to only a few inches or almost touching the phone to the Tag” (Wikipedia.com). The second question was: Is there a possibility to run a test here at Cal Poly considering the necessary equipment, materials, labor, and logistics behind this project? Professor Rong mentioned that it basically depends on the type of material, the device, and the printing process used for this particular project. She also said that, in terms of knowledge in electronics, the Graphic Communication department is still limited to simple circuits, and not something more complex or ambitious. “I think that knowledge wise we are not in the position that we understand electronics really well” (Rong, Appendix). Professor Keif said that it is possible to run a test of the prototype of a magazine, here at Cal Poly, considering static displays, things that appear and do not appear, electro luminescent displays like

Printed Electronics Applications for Publications • Abel Marquez

126 lighting up things, and simple things. On the other hand, it is more complicated to come out with a prototype that would include more sophisticated types of circuits in terms of logic. “If you are talking about things that have logic like gates and transistors, that’s a little bit more complicated but there might be hybrid approaches where you integrate conventional surface technologies all in some sort of a flex substrate” (Keif, Appendix). Professor Twomey agreed about the possibility to run a test, but she emphasized that it all depends on the printing process used and it would require some modifications. “Most publications if they are high volume are going to be printed sheet fed offset or offset printing and our printer has a coater on it and just recently Dr. Keif ran a test with the coater which is essentially a flexo plate and silver conductive ink. The other possibility is if you print digitally and then incorporating some sort of maybe screen printing but then you are doing two different steps so there is logistics, there is labor, those expenses because conductive inks are really expensive” (Twomey, Appendix). Philip Lazo mentioned that he thinks it is possible to run a test if the conductor is printed and a chip is mounted. The third question was: What do you think would be the cost of working on this kind of project and if there is a possibility to generate some revenue based on other examples? Professor Rong answered that the run length is not a big factor in this situation. The most expensive part are the conductive materials used like silver inks for example. “If you have a five pound can of silver that’s 10,000 dollars, so your material used is not offset to your volume, so you can print

127 10,000 copies it is still going to be expensive because your material is in there” (Rong, Appendix). She also mentioned that cheaper materials can be used, but performance would be sacrificed in this case. One option as a conductive material that can be used is carbon based inks which are cheaper and environmental friendly. Another option is graphene which derives from carbon, but it is still on development. “You don’t really have to use graphene and it is easier with carbon. Carbon can be used for conductive material as well. It is a low cost and it is environmental friendly so you don’t have to worry about it because everything turns in to carbon by the end. There is a lot of development so far and I haven’t really seeing a very successful sort of commercialized products that can be used for graphene” (Rong, Appendix). Professor Keif also agreed that the cost factor are the materials used for this kind of project. “Sometimes you don’t know going into it how expensive things are going to be but you have to figure that the inks are going to be quite expensive and by quite expensive I would say maybe as much as a dollar per magazine for a couple of displays or maybe more than that” (Keif, Appendix). Also he mentioned that the best way to generate revenue in a project like this is to obtain enough advertisements and the generation of interest through the right marketing campaign and promotion. “So it can be quite expensive but there are maybe ways especially if you customize that meaning you are basically selling advertisement as well to generate every month money back in. So I think it is possible to generate revenue especially if it creates enough buzz” (Keif, Appendix).

128 What is your gender? Answered: 85

What is your preference when it comes to reading articles?

What is your age?

Skipped: 0

Answered: 85

Skipped: 0

Answered: 85

Printed Electronics Applications for Publications â&#x20AC;˘ Abel Marquez

Male

18 - 24

Skipped: 0

Internet

25 - 34 Printed Magazines

Female

Both

55 - 44 Other (Please Specify)

Answer Choices

Responses

Answer Choices

Female

70.59%

Male

29.41%

Total

Answer Choices

Responses

18 - 24

80.00%

25 - 34

14.12%

35 - 44

4.71%

45 - 54

0.00%

Other (please specify)

1.18%

Total

How important is price to you when purchasing a magazine? Answered: 85

29.41%

15.29%

Both

55.29%

Total

Skipped: 0

Answered: 85

Are you familiar with the term printed electronics and its different applications?

Skipped: 0

Science & Technology

Answered: 85

Printing Industry Celebrities

Not at All Important

Internet Printed Magazines

What are you most interested in when reading an article?

Moderately Important

Responses

Sports

Skipped: 0

I have heard about it, but I am not sure about its applications

Other (Please Specify)

Slightly Important

World & Local News

Quite Important

Health & Beauty

Yes

Extremely Important Social Events

Answer Choices

Responses

Answer Choices

Not at All Important

7.06%

Slightly Important

11.76%

Moderately Important

28.24%

Quite Important

40.00%

Extremely Important

12.94%

Total

Responses

Yes

48.24%

Sports

3.53%

25.88%

Health & Beauty

25.88%

I have heard about it, but I am not sure about its applications

25.88%

Celebrities

4.71%

World & Local News

24.71%

Science & Technology

24.71%

Social Events

4.71%

Printing Industry

2.35%

Other (Please Specify)

9.41%

Total

2 8 85

Total

129

Would you be interested in purchasing or subscribing to a magaine called â&#x20AC;&#x153;The Inter-Activeâ&#x20AC;?, which would cost more than a regular magazine, but would incorporate printed electronics in order to make it more appealing and interactive by having text and graphics that emit light, pages that change color, printed buttons that emit sound, and the possible incorporation of augmented reality and QR codes?

How often do you read printed magazines? Answered: 85

Skipped: 0

Answered: 85

Skipped: 0

Maybe

Not Often at All

(depending on the price)

Other

Extremely Often

(please specify)

Moderately Often

Yes Slightly Often

Maybe (depending on the content)

Very Often Answer Choices

No Responses

Answer Choices

Responses

Not Often at All

28.24%

Yes

16.47%

Slightly Often

43.53%

17.65%

No Maybe

14.12%

Moderately Often Very Often

9.41%

Extremely Often Total

1.18%

49.41%

(depending on the price)

18.82%

Other (please specify)

1.18%

(depending on the content)

1 85

Graphs representing the results of the survey.

Maybe

Total

1 85

Printed Electronics Applications for Publications • Abel Marquez

130 Professor Twomey said that the possibility to generate revenue will be based on the readership response and advertisement as well. “I can see advertisers knowing that hey if I have somebody staring at my add 11 times longer than if they were just flipping through I can see advertisers very much interested in it. It depends on the readership and the magazine” (Twomey, Appendix). Philip Lazo mentioned that the cost of working on a project like this would be a few thousand dollars in terms of printing, mounting the electronic components, and working with the content management company. The fourth question was: What do you think could be the necessary implementations in order to create a prototype like this, probably run in and test it, and evaluate its effectiveness? Professor Keif answered that some things have to be taken in consideration to achieve all these goals like the interactive communication, the technologies to be able to produce it in house, the materials, and the power supply for the different circuits used for this project. Philip Lazo mentioned that RockTenn, the company he works for, has not done a lot of implementations in the field of printed electronics for retail displays, but he offered five useful steps in terms of a new product introduction process: 1. “Understand your target market and scope out opportunities to solve specific customer pain points. 2. Define the new product. What is the job to be done? Do the economics of the product make sense up front? Is there a financial return for the client? Should use NPV and IRR as metrics. The model uses a sanity check before starting.

131 3. Develop a working demo and show it around to generate client interest. 4. Pitch a pilot to the client. Optimally client pays for part of the pilot. Get skin in the game early. 5. Analyze the result of the pilot. This is your best chance to develop the real value propositions based on financial and non-financial metrics. Sales lift is ultimate metric for retail but depending on product you could also use opex reductions. 6. Scale into high volume productionâ&#x20AC;? (Lazo, Appendix). Tim Luong, National Sales Engineer with Ceradrop MGI Group, was not contacted since he never responded and did not answer the interview questions. Moreover, a survey was conducted to students from the Graphic Communication Department. The purpose of this survey was to measure the level of interest in a monthly magazine that would incorporate printed electronics to make it more appealing and interactive. Also, a fictitious prototype of the cover was presented to students and the possible use of printed electronics applications was also mentioned in the survey. The survey was sent to all the students from the GrC department and from the approximate 300 students, only 85 answered the questions. These are the survey results: Finally, the hypothetical cover prototype was presented along a question more specific towards this new project called The Inter-Active magazine. The question was: The cover of the prototype can be found in the appendix.

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Printed Electronics Applications for Publications â&#x20AC;˘ Abel Marquez

Concluding Remarks After the survey was conducted with students and the experts on the field responded to the questions during the interviews, the analysis of the results indicated that the printing industry can potentially benefit by the incorporation of printed electronics in the publications and packaging fields. Coming up with a prototype for a monthly magazine requires a lot of investment. Prototype of printed electronics magazine.

It requires materials, power supplies, printing processes, and labor hours. It is difficult to come out with a prototype, test it, and evaluate its results in one quarter or two. This project would involve more people who specialize in different majors rather than Graphic Communication like Physics, Business, Editorial, etc. Also, many students expressed that they would be willing to purchase or subscribe to a magazine that incorporates printed electronics if the content is relevant to them and the cost is not expensive. Carbon based materials are ideal because they are not as expensive as silver, which is a better semi conductive material, but costs more. A project like this would require sponsorship from advertisements, an effective marketing campaign, and interest in readership.

133 Cal Poly is not in the position currently of coming out with an ambtious project like this as this technology is still developing, but some steps can be accomplished if effort and research is done in collaboration with other departments on campus, the local businesses, and the community of students and local people. Until this moment, the packaging industry has demonstrated a lot of interest in printed electronics development and also, it has emphasized the importance of having interaction with the consumers through point of purchase displays in retail stores and small businesses. On the publications side, interactions with the readers have been done through the use of smartphones, augmented reality, and QR codes. E-magazines, for example, have become popular because younger generations seem to prefer the digital world than the conventional printing world. To become more competitive in the future, the printing industry should consider digital technologies as another vehicle to generate revenue and interest among the readers. That is the reason the ficticious â&#x20AC;&#x153;The Inter-Activeâ&#x20AC;? magazine would incorporate printed electronics to make it more appealing and interactive by having text and graphics that emit lights, pages that change color, printed buttons that emit sounds, and the possible incorporation of augmented reality and QR codes. Printed electronics is the blue ocean that can offer potential for the printing industry if a lot of sailors are brave enough to take the challenge and devote themselves to the restoration of a hurt industry that it is evolving and requires innovative people from the Graphic Communication industry.

134

References

Printed Electronics Applications for Publications â&#x20AC;˘ Abel Marquez

Gilleo, Ken (Mar 2007) The Real Printed Electronics. Retrieved from http://www. et-trends.com/files/paper_uploads/The%20Real%20Printed%20 Electronics.pdf Hariharan, Malini (Feb 2006) Printed electronics roll off the presses. Retrieved from h tt p : / / w w w. i c i s . c o m / r e s o u r c e s / n ew s / 2 0 0 6 / 0 2 / 0 6 / 2 012 3 9 9 / p r i n t e d - e l e c t r o n ics-roll-off-the-presses/search.proquest.com/abicomplete/docview/194756262/ A930F7977E094400PQ/4?accountid=10362 Harrop, Peter (Feb 2007) PRINTED ELECTRONICS: A Merging of Industries. Retrieved from http://www.thefreelibrary.com/Printed+electronics%3A+a+merging+of+industries%3A+every+now+and+again+a...-a0160109629 search.proquest.com/abicomplete/ docview/213887614/14327062311501FFD07/2?accoun tid=10362 Nilsson, Hans-Erik (Jul 31, 2012) System Integration of Electronic Functions in Smart Packaging Applications. Retrieved from http://ieeexplore.ieee.org/xpl/articleDetails. jsp?arnumber=6255781&tag=1 Scott, Alex (Jul 2006) Electronic Chemicals: Printed Electronics Moves Toward Mass Production. Chemical Week, Vol. 168 Issue 23, p16: Trade Publication. Schroeter, Klaus G. (Nov 5, 2007) Printed-Electronics Technology Flexes Its Muscle. Retrieved from http://electronicdesign.com/digital-ics/printed-electronics-technology-flexes-its-muscle search.proquest.com/docview/221007418/fulltext?source=fedsrch&accountid=10043 Sridhar, Ashok, Blaudeck, Thomas, Baumann, Reinhard R. (2014) Inkjet Printing as a Key Enabling Technology for Printed Electronics. Retrieved from http://www.sigmaaldrich. com/technical-documents/articles/material-matters/inkjet- printing-as.html

135

ABEL MARQUEZ I am a Graphic Communication student with a concentration in Web and Digital Media. I am a super senior and this is my last quarter at Cal Poly. My plans are to move to Wisconsin and work for Quad/Graphics. I had an internship over there this past summer and was offered a position under the Corporate Trainee Program. My hobbies are traveling to different places, experiencing new things in life, and getting to know people with different backgrounds, ideologies, and cultures. I also like technology and art, which is the reason Graphic Communication is the perfect fit for me. I enjoy visiting museums and taking photos, meeting with friends, going to concerts or parties, exercising and going to the movies. I was born in the beautiful city by the bay, San Francisco, but raised in San Juan de los Lagos, Mexico. I am really passionate about the field of printed electronics, which is the reason I chose that topic for my senior project.

136

JORDAN TRIPLETT President

KRISTEN MINLSCHMIDT Chapter Officers and Committee Chairs

Vice President Research Chair

SARAH PILEGARD Treasurer

137

ISABELLA MONTALVO Design & Production Chair

KRISTINA SANDERS Social & Fundraising Chair

MEG FUKAMAKI Digital Media Chair

138

Chapter Members

The 2014-2015 Cal Poly TAGA Student Chapter would like to thank the following people for their help and contributions: Cal Poly Graphic Communication Department Cal Poly University Graphics Systems Professor Brian Lawler, Chapter Advisor Dr. Xiaoying Rong Dr. Frank Romano

139

Colophon The journal was designed using Adobe InDesign, Illustrator and Photoshop CC. The typefaces used were Klinic Slab and Univers LT Std. Files were prepared for print using the Agfa Apogee Prepress and workflow. A Creo Trendsetter was used to produce printing plates for the cover. The printing of the cover was first done in-house using the GrC department’s Heidelberg Speedmaster CD74 press. The cover stock used was Nordic C1S cover. Students worked on the press under the guidance of Cal Poly University Graphics System (UGS) managers. The logo on the cover was done in-house using a screen printing press. The journal’s text was produced on the GrC department’s Konica Minolta Bizhub C1100. The text stock used was New Page 80# dull text. Students in TAGA worked to set up and guide the press during production under the guidance of UGS managers. Substrates were cut to the proper size using a Polar cutter, and the journal was perfect bound using a Duplo DB-280 Perfect Binder. The Cal Poly TAGA website (calpolytaga.com) was created using WordPress (wordpress.com). Videos featured on the website were edited using Adobe Premiere Pro CC.