printing methods can meriรง
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contents DIE CUTTING
2-3
EMBOSSING
4-5
GRAVURE
6-8
FOIL STAMPING
9-11
FLEXOGRAPHY
12-15
OFFSET LITHOGRAPHY
16-17
SCREEN PRINTING
18-23
GLOSSARY
24-30
minor printing die cutting
Die cutting is a manufacturing process used to generate large numbers of the same shape from a material such as wood, plastic, metal, or fabric. The die cut shapes are sometimes called “blanks,� because they are usually finished and decorated before being sold. The process is widely used on an assortment of materials all over the world, and many manufactured products contain several die cut components, often assembled together in a series of steps to create a finished product. Sharp specially shaped blades are used in die cutting. The blade is bent into the desired shape and mounted to a strong backing. The result is known as a die. The material being cut is placed on a flat surface with a supportive backing, and the die is pressed onto the material to cut it. Depending on what is being made, a single die might cut one piece of material, or it might be designed to slice through multiple layers, generating a stack of blanks. Many consumers find it helpful to consider a cookie cutter when thinking about die cutting. The cookie cutter is a type of die which is capable of cutting out a potentially infinite amount of blanks. Each blank will be exactly the same shape and size, meaning that the blanks can be cooked uniformly together and decorated at will for individuality.
Die cut example for Soul of California Label
The alternative is cutting out each cookie by hand, a painstaking process which would result in irregular final products. Creating dies is meticulous work. The die must be designed so that it efficiently cuts the desired material with minimal waste. Most factories which use die cutting as part of their manufacturing process have techniques for recycling material left over from die cutting, but they want to avoid excess if possible. Often, multiple dies are fitted together on one mount, nestled with each other for maximum efficiency. Material left over from the die cutting process may be melted down and reused, or reworked into other components. Common examples of die cut items include keys, paper products, and flat plastic pieces which can be snapped together. Die 4
Jewellery Kit bye Wink
die cutting cutting is limited, because it can only really be used to produce flat objects. For more dimensional shapes, other manufacturing techniques such as molds need to employed. Dies can also range widely in size from cookie cutters to massive machines designed to cut out ship components. With large dies, it is important to observe safety precautions while die cutting, as an industrial die designed to slice through metal can also remove a limb without difficulty. The early 1900s brought about great advancements in diecutting machines. The original machines were operated by a belt system, but soon a swing-arm clicker press was added. These machines could use 9/16 inches and 3/4 inch heat-treated single and double clicker dies. For the shoe industry this meant that other parts of the shoes could now be cut out, reducing the price of a single pair of shoes even more. Soon, die-cut machines were invented to mass produce other products such as tubing, plastics, metal and even food items.
Austin Walsh die cut identity
The die-cutting machines first used in homes and schools were smaller versions of the professional die-cutting machine. But, with the evolution of technology, hand-held die cutting tools were introduced, as well as small table top machines. These machines made mass production of crafts and school-related decorations available to a large variety of people. However, in most cases, moving metal plates and resetting the die-cutting machine were still a part of the die-cutting process. There are many computerized die-cutting machines on the market. These machines have far surpassed the simple handheld mallet die cut tool that the cobbler kept in his workshop. Many of these machines connect directly to a computer, allowing heavily detailed crafts to be made. Other machines use cartridges and movable dies.
Jewellery Kit bye Wink
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embossing Embossing is an artistic technique which creates a pattern on a material such as paper, metal, fabric, leather, or wood. The pattern can be raised or in relief, depending on how it is embossed. Many consumers interact with embossed items on a regular basis, ranging from embossed book covers to notarized documents. As an artistic technique, embossing has been around for hundreds of years, with numerous artifacts from tooled leather belts to metal ornaments showing signs of embossing There are a number of ways to emboss something. Some artists emboss by hand, using hand held tools to stamp out a pattern in the material being embossed. This technique will create unique raised designs which cannot be replicated. Embossing of this style is often used for customized art projects, or when ordering an embossing die would seem impractical. Both dry and heat embossing techniques are used for hand embossing projects, depending on how the artist wants the finished piece to look.The other type of embossing uses a die or roller. Rollers are used for continuous embossing, such as manufacturing leather with a uniform pattern.
Embossing example by John T. Drew
A die embosses a single piece of material at a time, but it can be used again and again. With both dies and rollers, the pattern to be embossed is carved in reverse, so that when the die is pressed against the material, the desired pattern will show up in the correct form. Typically, a die is designed to be mounted into a press, and is not hand-held. Both dies and rollers also may use heat in order to be more effective. In printing, embossing can add a great deal to printing costs. Embossing represents a separate run through the press, usually, unless a die is designed to be inked. More commonly, printed materials are “blind embossed,� meaning that they are embossed without the use of ink. When blind embossing is used, it is important to ensure that the embossing die is properly registered, so that it will mesh with the inked patterns which were produced first. Embossing may also be used in paper making, to distinctively stamp individual sheets of paper so that 6
Blind-embossed for the calender
embossing they will be identifiable to consumers.Notaries public and other officials use hand held embossing stamps to mark documents from their offices. An embossed pattern can be difficult to forge, ensuring that the document is official and distinctive. Hand held embossing stamps can be ordered from numerous specialty supply companies, and they are extremely easy to use. Hand embossers are also handy for marking personal possessions such as books. Embossing is an elegant process that changes the nature of the material that has been embossed. More often than not it elevates the standard and quality of the product. A notary’s embossed seal can give much weight to a regular piece of paper. Similarly, an embossed wedding card immediately changes the entire meaning conveyed by the invitation. The recipient is informed not only about the wedding but also that it is going to be a high profile wedding and an elegant ceremony. Embossing thus makes things more beautiful than they originally are. The simplest of object can become pieces of art worthy of the highest praise by using a technique as easy as embossing. Of course, how good an embossed object looks depends entirely on the quality of embossing. Poor quality embossing can completely kill the appeal of an object. However, good quality embossing can make an object positively breathtaking.
Embossing example by Mark Hampshire
Embossing involves the creation of an impression by placing the dies in contact with the stock under high pressure. Different kinds of paper show different kinds of embossed effects. There are also many different kinds of embossing that can be done like blind embossing, tint embossing and glazing to achieve different results. The process of embossing is relatively inexpensive and has many uses. Embossing is used for aesthetic purposes as well as functional uses in industries. From embossing names on credit cards to embossed Braille books for the blind, embossing has a wide range of applications and uses.Thus, embossing is a technique that adds elegance and sensuality to any paper or surface.
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gravure Rotogravure (roto or gravure for short) is a type of intaglio printing process, that is, it involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a copper cylinder because, like offset and flexography, it uses a rotary printing press. The vast majority of gravure presses print on rolls (also known as webs) of paper, rather than sheets of paper. (Sheetfed gravure is a small, specialty market.) Rotary gravure presses are the fastest and widest presses in operation, printing everything from narrow labels to 12 feet (4 m)-wide rolls of vinyl flooring. Additional operations may be inline with a gravure press, such as saddle stitching facilities for magazine/brochure work. Once a staple of newspaper photo features, the rotogravure process is still used for commercial printing of magazines, postcards, and corrugated (cardboard) product packaging. In the last quarter of the 19th century, the method of image photo transfer onto carbon tissue covered with light-sensitive gelatin was discovered, and was the beginning of rotogravure. In the 1930s–1960s, newspapers published relatively few photographs and instead many newspapers published separate rotogravure sections in their Sunday editions. These sections were devoted to photographs and identifying captions, not news stories. Irving Berlin’s song Easter Parade specifically refers to these sections in the lines “the photographers will snap us, and you’ll find that you’re in the rotogravure.” And the song Hooray for Hollywood contains the line “...armed with photos from local rotos” referring to young actresses hoping to make it in the movie industry.
Otto M.Lilien Gravure
In 1932 a George Gallup “Survey of Reader Interest in Various Sections of Sunday Newspapers to Determine the Relative Value of Rotogravure as an Advertising Medium” found that these special rotogravures were the most widely read sections of the paper and that advertisements there were three times more likely to be seen by readers than in any other section. A rotogravure printing press has one printing unit for each color, typically CMYK or cyan, magenta, yellow and key (printing terminology for black). The number of units varies depending 8
Gravure process and methods
gravure on what colors are required to produce the final image. There are five basic components in each color unit: an engraved cylinder (AKA “Gravure cylinder”) (whose circumference can change according to the layout of the job), an ink fountain, a doctor blade, an impression roller, and a dryer. While the press is in operation, the engraved cylinder is partially immersed in the ink fountain, filling the recessed cells. As the cylinder rotates, it draws ink out of the fountain with it. Acting as a squeegee, the doctor blade scrapes the cylinder before it makes contact with the paper, removing ink from the non-printing (non-recessed) areas. Next, the paper gets sandwiched between the impression roller and the gravure cylinder. This is where the ink gets transferred from the recessed cells to the paper. The purpose of the impression roller is to apply force, pressing the paper onto the gravure cylinder, ensuring even and maximum coverage of the ink. Then the paper goes through a dryer because it must be completely dry before going through the next color unit and absorbing another coat of ink. Because gravure is capable of transferring more ink to the paper than other printing processes, gravure is noted for its remarkable density range (light to shadow) and hence is a process of choice for fine art and photography reproduction, though not typically as clean an image as that of sheet fed litho or web offset litho. Gravure is widely used for long-run magazine printing in excess of 1 million copies. Gravure’s major quality shortcoming is that all images, including type and “solids,” are actually printed as dots, and the screen pattern of these dots is readily visible to the naked eye. Examples of gravure work in the United States are typically long-run magazines, mail order catalogs, consumer packaging, and Sunday newspaper ad inserts. Other application area of gravure printing is in the flexible packaging sector. A wide range of substrates such as Polyethylene, Polypropylene, Polyester, BOPP, etc., can be printed in the gravure press. Gravure is an industrial printing process mainly used for the high-speed production of large print magazines and runs at a
Old gravure machine constant and top quality, such as in the printing of large numbers of magazines and mail order catalogues. Other uses for the gravure process are in wallpaper and laminates for furniture where quality and consistency are desired. Rotogravure presses for publication run at 45 feet (14 m) per second and more, with paper reel widths of over 10 feet (3 m), enabling an eight-unit press to print about seven million fourcolour pages per hour. Gravure printing is a direct printing process that uses a type of image carrier called intaglio. Intaglio means the printing plate, in cylinder form, is recessed and consists of
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gravure cell wells that are etched or engraved to differing depths and/ or sizes. These cylinders are usually made of steel and plated with copper and a light-sensitive coating. After being machined to remove imperfections in the copper, most cylinders are now laser engraved. In the past, they were either engraved using a diamond stylus or chemically etched using ferric chloride which creates pollution. If the cylinder was chemically etched, a resist (in the form of a negative image) was transferred to the cylinder before etching. The resist protects the non-image areas of the cylinder from the etchant. After etching, the resist was stripped off. The operation is analogous to the manufacture of printed circuit boards. Following engraving, the cylinder is proofed and tested, reworked if necessary, and then chrome plated. In direct image carriers such as gravure cylinders, the ink is applied directly to the cylinder and from the cylinder it is transferred to the substrate. Modern gravure presses have the cylinders rotate in an ink bath where each cell is flooded with ink. A system called a “doctor blade” rides against the cylinder to wipe away excess ink, leaving ink only in the cell wells. The doctor blade is normally positioned as close as possible to the nip point of the substrate meeting the cylinder. This is so that ink in the cells has less time to dry before meeting the substrate at the impression rollers. The capillary action of the substrate and the pressure from impression rollers draw/force the ink out of the cell cavity and transfer it to the substrate. Gravure cylinders nowadays are typically engraved digitally by a diamond tipped or laser etching machine. On the gravure cylinder, the engraved image is composed of small recessed cells or dots that act as tiny wells. Their depth and size control the amount of ink that is transferred to the substrate (paper or other material, such as plastic or foil) via pressure, osmosis, and electrostatic pull. (A patented process called “Electrostatic Assist” is sometimes used to enhance ink transfer.)
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Otto M.Lilien Gravure
foil stamping Foil stamping uses heat and metallic film in a specialty printing process that produces a shiny design on paper, vinyl, textiles, wood, hard plastic, leather, and other materials. Foil stamping, also called hot stamping, dry stamping, foil imprinting, or leaf stamping, can be combined with dimensional embossing to make letters and images on business cards, book covers, gift cards, office folders, and a whole host of professional or personal items. Instead of using magnetism, plates, or inks to print words and shapes, foil stamping uses dies, or sculpted metal stamps. The heated dies seal a thin later of metallic leaf onto a surface. The foil comes in a wide roll, large enough for several passes, backed by Mylar. The hot die works similarly to a letterpress. Once heated, it presses the foil against the substrate material with enough pressure that the foil sticks only in the intended places, leaving a slight imprint. Using several layers of foil in different colors or combining ink and foil can embellish this simple “flat” stamp. Imprinting and embossing adds even more dimensionality. The edges of the foil stamp may be straight, curved, or sculpted to make the image pop or float above the page. Foil leaf is available in every imaginable color and pattern, like standard gold or marbleized green. Rarer types of leaf come in matte, pearlescent, holographic, opalescent, or glossy finish. Semi-transparent layers allow an under color to show through. Not only does it provide a uniquely vibrant image with depth, foil stamping can be applied to a much more diverse selection of substrates in comparison to ink. The cover of a leather photograph album could be printed with your family’s monogram, or a cloth bookmark with a favorite literary quote. Impressive wedding invitations might have intertwining silver vines, blue flowers, and gold rings. Businesses use foil stamping to identify folders, cards, signs, and magnets with their logo. The reflective and unusual treatment is sure to catch the eye of a potential customer.
Foil stamping machines, also known as hot foil stampers, use heat to transfer metallic foil to a solid surface. Examples of items that are foil stamped include pencils, napkins, matchbooks, photographs and books. The foil stamp is a permanent process. These machines are popular with wedding businesses, photography studios and other businesses that need to brand or mark products. A similar machine, called a foil fuser, creates a similar look in a process called foil fusing in which foil is fused to printer toner by means of heat There are two primary types of foil stamping machines. The first type is manual and the second is pneumatic (air powered). Manual foil stampers are ideal for low to medium volume jobs and the pneumatic is ideal for medium to high-volume jobs. Foil stampers do create a lot of heat in order to transfer the foil to the surface of an object. Safety must be observed when changing type sets to prevent one from being burned. The technical foundation of foil stamping was laid in Germany in the late nineteenth century, when Ernst Oser developed a process to manufacture a synthetic gold leaf which, through a heat process, could be transferred to paper. This dramatically decreased the cost of a gold-leaf-look; the synthetic product became known either as hot-stamped foil, referring to its printing process, or as roll leaf, referring to its manufactured form (like a roll of ribbon, or saran wrap). Artists conversing among themselves commonly refer to it as ‘foil’. In the century following its development, roll leaf spread widely, particularly in the wake of World War I, with the revocation of German patent rights. Initially, roll leaf mimicked authentic gold and silver leaf. In the second half of the twentieth century, however, its palette exploded. Now, foils are available as translucent pearlescents, transparent tints (also referred to as “blind emboss”), specialty, holographics (both solid colors and patterns; opaque, and translucent), and pigments (opaque foils which can seem velvety or dense in their color weight). Not all of
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foil stamping these varieties involve any metallic elements, but the majority of all foils are a gold or silver of some kind. Held in the hands prior to printing, like a sealed tube of paint or another stock art supply, roll leaf foil can seem like a very thin, homogenous roll of colored cellophane. In actuality, though, it is a product comprising at least three layerscarrier, wax release, and color—and frequently two additional others: metal, and adhesive. The carrier is the polyester substrate, far less than a millimeter thick, upon which the other layers are chemically fabricated. The wax release coat dissipates when printing, and enables the polyester carrier coat to be peeled away and discarded. Professor Virginia A. Myers’ initial attraction to foil stamping was its vast and exhilarating palette, and this remains a strongly influential factor for new students who wish to embrace these revolutionary and highly contemporary printmaking techniques. Roll leaf foil provides the opportunity to work with holographics; metallics; sheer, dry washes of color; luminescent and pearlized color, in one material and with one set of processes. To wield this unprecedented vocabulary of color and light hand-inhand with an established artistic vision may give voice to unspoken possibilities.
Austin Walsh die cut identity
However, artists new to foil imaging can find the palette to be overwhelming. Roll leaf foil comes in rolls which are a bit less approachable than a tube of paint, or a can of ink. They are industrial products, manufactured for industrial foil stamping, for many kinds of common commercial products. A group of rolls can be intimidating in its commerciality, and can stymie selection by its very diversity of choice. Overcoming those obstacles, with play, practice, technique and skill, into a space where fine art can be created, is the critical task of foil imaging practice. One of the ways Myers initiates artists into the foil imaging palette is to have them produce “scrapbox monos,” an assignment that circumvents the standoffish aura of fresh rolls of foil by restricting their materials to the scrapbox: used, but not depleted, foils saved from previous students’ work. These 12
Austin Walsh die cut identity detail
foil stamping scrapbox foils enable students to produce works which are a far cry from the commonly known commercial products, and which enable the students to begin developing their own voice in this new medium. Another way to render the palette more approachable is to make a color chart. Foil color charts can be quite elaborate, sometimes including up to six total layers of two or three overlapping foils: some foil imaging works require that nuance of hue. They can also be quite simple, designed to compare a handful of foils layered over each other or to provide precise colors or textures to satisfy personal aesthetic needs. Depending on the project, they can incorporate paint, ink, and other mediums, as well. Regardless of their scale, they are invaluable for focusing the expansive palette into the needed range. While revolutionary, foil imaging holds a place in the pantheon of traditional printmaking techniques by virtue of being editionable. In addition to being editionable on its own, it is frequently combined with other traditional printmaking techniques, including intaglio, lithography, and relief. However, Professor Myers encourages her student research teams to experiment, and to cross-pollinate this new medium with other art disciplines. Hence, painters, metalsmiths, fabric artists, and photographers, among others, have incorporated foil imaging into their full bodies of work.
David Reinfurt design for ORD inc Designer. USA
Across the board of all these variants, what differentiates foil imaging, the art form, from foil stamping, the industrial process, seems to rest in the working of the foil. Artists, versus commercial foil stamping printers, alter roll leaf foils with a variety of techniques, including stenciling, cutting, wooling out, alcohol manipulation, graphite transfers, acid etching, embossing, and resists. After making scrapbox monos, and color charts, these are the techniques which enable artists to control the roll leaf foil palette, and the artwork to say what needs to be visually stated.
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minor printing major die cutting flexography
Flexography (often abbreviated to flexo) is a form of printing process which utilizes a flexible relief plate. It is basically an updated version of letterpress that can be used for printing on almost any type of substrate including plastic, metallic films, cellophane, and paper. It is widely used for printing on the non porous substrates required for various types of food packaging. In 1890, the first such patented press was built in Liverpool, England by Bibby, Baron and Sons. The water-based ink smeared easily, leading the device to be known as “Bibby’s Folly”. In the early 1900s, other European presses using rubber printing plates and aniline oil-based ink were developed. This led to the process being called “aniline printing”. By the 1920s, most presses were made in Germany, where the process was called “gummidruck”. During the early part of the 20th century, the technique was used extensively in food packaging in the United States. However, in the 1940s, the Food and Drug Administration classified aniline dyes as unsuitable for food packaging. Printing sales plummeted. Individual firms tried using new names for the process, such as “Lustro Printing” and “Transglo Printing,” but met with limited success. Even after the Food and Drug Administration approved the aniline process in 1949 using new, safe inks, sales continued to decline as some food manufacturers still refused to consider aniline printing. Worried about the image of the industry, packaging representatives decided the process needed to be renamed.
Example of flexography by Daniel Mason
In 1951 Franklin Moss, then the president of the Mosstype Corporation, conducted a poll among the readers of his journal The Mosstyper to submit new names for the printing process. Over 200 names were submitted, and a subcommittee of the Packaging Institute’s Printed Packaging Committee narrowed the selection to three possibilities: “permatone process”, “rotopake process”, and “flexographic process”. Postal ballots from readers of The Mosstyper overwhelmingly chose the latter, and “flexographic process” was chosen. Design by Mytton Williams 14
flexography die cutting Originally, flexographic printing was rudimentary in quality. Labels requiring high quality have generally been printed using the offset process until recently. Since 1990 great advances have been made to the quality of flexographic printing presses, printing plates and printing inks. The greatest advances in flexographic printing have been in the area of photopolymer printing plates, including improvements to the plate material and the method of plate creation. Digital direct to plate systems have been a good improvement in the industry recently. Companies like AV Flexologic, Dupont, MacDermid, Kodak and Esko have pioneered the latest technologies, with advances in fast washout and the latest screening technology. Laser-etched ceramic anilox rolls also play a part in the improvement of print quality. Full color picture printing is now possible, and some of the finer presses available today, in combination with a skilled operator, allow quality that rivals the lithographic process. One ongoing improvement has been the increasing ability to reproduce highlight tonal values, thereby providing a workaround for the very high dot gain associated with flexographic printing.
Example of flexography by Daniel Mason
PROCESS OVERVIEW Platemaking The first method of plate development uses light-sensitive polymer. A film negative is placed over the plate, which is exposed to ultra-violet light. The polymer hardens where light passes through the film. The remaining polymer has the consistency of chewed gum. It is washed away in a tank of either water or solvent. Brushes scrub the plate to facilitate the “washout� process. The process can differ depending on whether solid sheets of photopolymer or liquid photopolymer are used, but the principle is still the same. The plate to be washed out is fixed in the orbital washout unit on a sticky base plate. The plate is washed out in a mixture of water and 1% dishwasher soap, at a temperature of approximately 40°C. The unit is equipped with
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flexography a dual membrane filter. With this the environmental burdening is kept to an absolute minimum. The membrane unit separates photopolymer from the washout water. After addition of absorb gelatine for example, the photopolymer residue can be disposed of as standard solid waste together with household refuse. The recycled water is re-used without adding any detergent. The second method used a computer-guided laser to etch the image onto the printing plate. Such a direct laser engraving process is called digital platemaking. Companies such as AV Flexologic, Polymount and Screen from The Netherlands are market leaders in manufacturing this type of equipment. The third method is to go through a molding process. The first step is to create a metal plate out of the negative of our initial image through an exposition process (followed by an acid bath). This metal plate in relief is then used in the second step to create the mold that could be in bakelite board or even glass or plastic, through a first molding process. Once cooled, this master mold will press the rubber or plastic compound (under both controlled temperature and pressure) through a second molding process to create the printing plate.
Design by Mytton Williams
Mounting For every colour to be printed, a plate is made and eventually put on a cylinder which is placed in the printing press. To ensure an accurate picture is made, mounting marks are made on the flexographic plates. These mounting marks can be microdots (down to 0.3 mm) and/or mounting crosses. To make a complete picture, regardless of printing on flexible film or corrugated paper, the image transferred from each plate has to fit exactly in the images transferred from the other colors. Highly accurate and specific machinery is made for mounting these plates on the printing cylinders. One of the latest advances in this field is Fully Automatic Mounting Machine (FAMM), for which AV Flexologic won the FTA Technical Innovation Award in 2007. Printing A flexographic print is made by creating a positive mirrored master of the required image as a 3D relief in a rubber or 16
A cosmetics Design by Mytton Williams
flexography polymer material. Flexographic plates can be created with analog and digital platemaking processes. The image areas are raised above the non image areas on the rubber or polymer plate. The ink is transferred from the ink roll which is partially immersed in the ink tank. Then it transfers to the anilox roll (or meter roll) whose texture holds a specific amount of ink since it is covered with thousands of small wells or cups that enable it to meter ink to the printing plate in a uniform thickness evenly and quickly (the number of cells per linear inch can vary according to the type of print job and the quality required). To avoid getting a final product with a smudgy or lumpy look, it must be ensured that the amount of ink on the printing plate is not excessive. This is achieved by using a scraper, called a doctor blade. The doctor blade removes excess ink from the anilox roller before inking the printing plate. The substrate is finally sandwiched between the plate and the impression cylinder to transfer the image Ink control The ink is controlled in the flexographic printing process by the inking unit. The inking unit can be either of Fountain Roll system or Doctor Blade System. The Fountain roll system is a simple old system yet if there is too much or too little ink this system would likely not control in a good way. The doctor blade inside the Anilox roller uses cell geometry and distribution. These blades insure that the cells are filled with enough ink.
Colour Management For Packaging
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offset lithography Offset lithography is a printing technique which is widely used around the world. Most books, newspapers, and magazines are printed using offset lithography, and this printing technique is widely regarded as the workhorse of printing, because it is fast, efficient, cheap, and relatively easy. The “offset” in the name refers to the fact that the ink is transferred to a separate surface before being applied to the paper. The first step in offset lithography is making a plate with the image to be printed. If the image is in black and white, only a single plate is required, because the plate can simply be inked with black ink. Color images are produced using a four-color separation process, in which four different plates are made for the cyan, magenta, yellow, and key (black) inks; when the plates are printed, the colors blend together visually, creating a color image. Plates in offset lithography are entirely flat, in contrast with the textured surfaces of engraved plates and movable type. They are made by creating a film negative of the image, placing it over a photo-sensitive plate, exposing it, and then developing it. Once the plate is made, it can be mounted in a press, and the real fun begins.
Copy preperation for offset printing by R.Randolph J.Buber
This printing technique takes advantage of the fact that oil and water do not mix. The plate is brushed with rollers coated in water, and then with rollers covered in ink. The ink is attracted to the parts of the plate which were exposed earlier, while the water keeps the unexposed portions clear so that they do not smear or transfer ink. Then, the plate transfers the ink to a rubber roller known as a “blanket,” and the blanket rolls across the paper; typically the paper is fed between the blanket and another roller to ensure that the image stays crisp. An offset press can run continuously, which makes it extremely fast. Depending on the job, the press may be sheet fed, which means that individual pieces are pulled from a stack by the press and run through, or web-fed, in which case the paper is on huge rollers. In both cases, the paper is typically run through an oven 18
Process and methods by R.Randolph J.Buber
offset lithography after printing so that it dries quickly, preventing smears, and then it can be cut, bound, folded, and prepared for distribution. The first press for offset lithography was developed in 1903, and the concept quickly caught on in the printing community. Offset presses vary in size from the massive presses used at commercial publishers, which can be bigger than a house, to smaller models around the size of dump trucks used at smaller printing companies. In 1903, Ira Washington Rubel noticed that the impression he got when an image accidentally transferred from the stone printing cylinder to the rubber impression plate was clearer than the original image. The soft rubber gave a cleaner, clearer image than the hard stone plate when it was transferred to paper. He used this information to invent a new type of printing press. About the same time, Charles and Albert Harris made a similar discovery and produced their own version of the offset press. The press made by the Harris Automatic Press Co. had a metal plate and a “blanket cylinder.� This arrangement allowed for the use of paper from large rolls. By the 1950s offset lithography was the most common form of printing and still is, with the addition of some digital pre-press innovations.
Scratchboard shading by Edward J.Buber
Art lithographs are a different and multi-step process. They also use oil-based inks, but each color is applied separately, by hand, and so an individual lithograph print takes months to produce. Offset lithographs of art are printed reproductions and thus are not original works of art. To see the difference between original hand-drawn lithographs and offset lithographs, use a magnifying glass. In an offset lithograph image you will see that the color is made up of lots of dots. On original lithographs, you will see a solid color.
The weber process by Edward J.Buber
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screen printing Screen printing is a printing technique that uses a woven mesh to support an ink-blocking stencil. The attached stencil forms open areas of mesh that transfer ink or other printable materials which can be pressed through the mesh as a sharp-edged image onto a substrate. A roller or squeegee is moved across the screen stencil, forcing or pumping ink past the threads of the woven mesh in the open areas. Screen printing is also a stencil method of print making in which a design is imposed on a screen of silk or other fine mesh, with blank areas coated with an impermeable substance, and ink is forced through the mesh onto the printing surface. It is also known as Screen Printing, silkscreen, seriography. This information may not be as accurate as it seems. There is considerable and semantic discussion about the process, and the various terms for what is essentially the same technique. Much of the current confusion is based on the popular traditional reference to the process of screen printing as silkscreen printing. Traditionally silk was used for screen-printing, hence the name silk screening. Currently, synthetic threads are commonly used in the screen printing process. The most popular mesh in general use is made of polyester. There are special-use mesh materials of nylon and stainless steel available to the screen printer.
Have a friend firmly hold the screen up to the wall.
Encyclopedia references, encyclopedias and trade publications also use an array of spellings for this process with the two most often encountered English spellings as, screenprinting spelled as a single undivided word, and the more popular two word title of screen printing without hyphenation. Screen printing first appeared in a recognizable form in China during the Song Dynasty (960–1279 AD). Japan and other Asian countries adopted this method of printing and advanced the craft using it in conjunction with block printing and hand applied paints. Screen printing was largely introduced to Western Europe from Asia sometime in the late 18th century, but did not gain large acceptance or use in Europe until silk mesh was more available 20
Flood the screen with ink.
screen printing for trade from the east and a profitable outlet for the medium discovered. Screen printing was first patented in England by Samuel Simon in 1907. It was originally used as a popular method to print expensive wall paper, printed on linen, silk, and other fine fabrics. Western screen printers developed reclusive, defensive and exclusionary business policies intended to keep secret their workshops’ knowledge and techniques. Early in the 1910s, several printers experimenting with photoreactive chemicals used the well-known actinic light activated cross linking or hardening traits of potassium, sodium or ammonium Chromate and dichromate chemicals with glues and gelatin compounds. Roy Beck, Charles Peter and Edward Owens studied and experimented with chromic acid salt sensitized emulsions for photo-reactive stencils. This trio of developers would prove to revolutionize the commercial screen printing industry by introducing photo-imaged stencils to the industry, though the acceptance of this method would take many years. Commercial screen printing now uses sensitizers far safer and less toxic than bichromates. Currently there are large selections of pre-sensitized and “user mixed� sensitized emulsion chemicals for creating photo-reactive stencils.
Pull the screen off the wall at the same time.
Joseph Ulano founded the industry chemical supplier Ulano and in 1928 created a method of applying a lacquer soluble stencil material to a removable base. This stencil material was cut into shapes, the print areas removed and the remaining material adhered to mesh to create a sharp edged screen stencil. Originally a profitable industrial technology, screen printing was eventually adopted by artists as an expressive and conveniently repeatable medium for duplication well before the 20th century. It is currently popular both in fine arts and in commercial printing, where it is commonly used to print images on Posters, T-shirts, hats, CDs, DVDs, ceramics, glass, polyethylene, polypropylene, paper, metals, and wood. Have a good plan for where you are headed to clean your screen.
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screen printing A group of artists who later formed the National Serigraphic Society coined the word Serigraphy in the 1930s to differentiate the artistic application of screen printing from the industrial use of the process. “Serigraphy” is a combination word from the Latin word “Seri” (silk) and the Greek word “graphein” (to write or draw). The Printer’s National Environmental Assistance Center says “Screenprinting is arguably the most versatile of all printing processes. Since rudimentary screenprinting materials are so affordable and readily available, it has been used frequently in underground settings and subcultures, and the non-professional look of such DIY culture screenprints have become a significant cultural aesthetic seen on movie posters, record album covers, flyers, shirts, commercial fonts in advertising, in artwork and elsewhere. Credit is generally given to the artist Andy Warhol for popularizing screen printing identified as serigraphy, in the United States. Warhol is particularly identified with his 1962 depiction of actress Marilyn Monroe screen printed in garish colours.
Put a shirt on the palette and print like we've taught you.
American entrepreneur, artist and inventor Michael Vasilantone would start to use, develop, and sell a rotary multicolour garment screen printing machine in 1960.[citation needed] Vasilantone would later file for patent on his invention in 1967 granted number 3,427,964 on February 18, 1969. The original rotary machine was manufactured to print logos and team information on bowling garments but soon directed to the new fad of printing on t-shirts. The Vasilantone patent was licensed by multiple manufacturers, the resulting production and boom in printed t-shirts made the rotary garment screen printing machine the most popular device for screen printing in the industry. Screen printing on garments currently accounts for over half of the screen printing activity in the United States. In June 1986, Marc Tartaglia, Marc Tartaglia Jr. and Michael Tartaglia created a silk screening device which is defined in its US Patent Document as, “Multi-colored designs are applied on a plurality of textile fabric or sheet materials with a silk screen 22
Lift your screen up, and bask in the magic of it all.
screen printing printer having seven platens arranged in two horizontal rows below a longitudinal heater which is movable across either row.” This invention received the patent number 4,671,174 on June 9, 1987, however the patent no longer exists. Graphic screenprinting is widely used today to create many mass or large batch produced graphics, such as posters or display stands. Full colour prints can be created by printing in CMYK (cyan, magenta, yellow and black (‘key’)). Screenprinting is often preferred over other processes such as dye sublimation or inkjet printing because of its low cost and ability to print on many types of media. Screen printing lends Warhol, Rob Ryan, Rauschenberg, Harry used screen printing artistic vision.
itself well to printing on canvas. Andy Blexbolex, Arthur Okamura, Robert Gottlieb, and many other artists have as an expression of creativity and
A screen is made of a piece of porous, finely woven fabric called mesh stretched over a frame of aluminium or wood. Originally human hair then silk was woven into screen mesh; currently most mesh is made of man-made materials such as steel, nylon, and polyester. Areas of the screen are blocked off with a nonpermeable material to form a stencil, which is a negative of the image to be printed; that is, the open spaces are where the ink will appear. The screen is placed atop a substrate such as paper or fabric. Ink is placed on top of the screen, and a fill bar (also known as a floodbar) is used to fill the mesh openings with ink. The operator begins with the fill bar at the rear of the screen and behind a reservoir of ink. The operator lifts the screen to prevent contact with the substrate and then using a slight amount of downward force pulls the fill bar to the front of the screen. This effectively fills the mesh openings with ink and moves the ink reservoir to the front of the screen. The operator then uses a squeegee (rubber blade) to move the mesh down to the substrate and pushes the squeegee to the rear of the screen. The ink that is in the mesh opening is pumped or squeezed by capillary action to
The ink will be wet, so be careful taking the shirt off the pallet.
Aren't you pretty!
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screen printing the substrate in a controlled and prescribed amount, i.e. the wet ink deposit is proportional to the thickness of the mesh and or stencil. As the squeegee moves toward the rear of the screen the tension of the mesh pulls the mesh up away from the substrate (called snap-off) leaving the ink upon the substrate surface. There are three common types of screenprinting presses. The ‘flat-bed’, ‘cylinder’, and the most widely used type, the ‘rotary’. Textile items printed with multi-colour designs often use a wet on wet technique, or colors dried while on the press, while graphic items are allowed to dry between colours that are then printed with another screen and often in a different color after the product is re-aligned on the press. The screen can be re-used after cleaning. However if the design is no longer needed, then the screen can be “reclaimed”, that is cleared of all emulsion and used again. The reclaiming process involves removing the ink from the screen then spraying on stencil remover to remove all emulsion. Stencil removers come in the form of liquids, gels, or powders. The powdered types have to be mixed with water before use, and so can be considered to belong to the liquid category. After applying the stencil remover the emulsion must be washed out using a pressure washer. Most screens are ready for recoating at this stage, but sometimes screens will have to undergo a further step in the reclaiming process called dehazing. This additional step removes haze or “ghost images” left behind in the screen once the emulsion has been removed. Ghost images tend to faintly outline the open areas of previous stencils, hence the name. They are the result of ink residue trapped in the mesh, often in the knuckles of the mesh, those points where threads cross. While the public thinks of garments in conjunction with screenprinting, the technique is used on tens of thousands of items, decals, clock and watch faces, balloons and many more products. The technique has even been adapted for more advanced uses, such as laying down conductors and resistors in multi-layer circuits using thin ceramic layers as the substrate. 24
University of the Arts London Camberwell Collage of Arts
screen printing
When you are finished,use a scrape the leftover ink into your ink jar.
Pull off the packing tape and throw it away.
Scrape the extra ink off your squeegee into the jar too.
Wash out the screen with a sponge.
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glossary Bleed // Printed content that extents past where the pages will be trimmed. Bleeds in the USA generally are 1/8 of an inch from where the cut is to be made. Bleeds in the UK and Europe generally are 2 to 5mm from where the cut is to be made. This can vary from print company to print company. Image courtesy of Can Meric
CMYK // CMYK is a scheme for combining primary pigments. The C stands for cyan (aqua), M stands for magenta (pink), Y is yellow, and K stands for black.
Image courtesy of Can Meric
Coated and Uncoated Paper // Coating is a process by which paper or board is coated with an agent to improve brightness or printing properties. By applying PCC, china clay, pigment or adhesive the coating fills the miniscule pits between the fibres in the base paper, giving it a smooth, flat surface which can improve the opacity, lustre and colour absorption ability. www.xinyontai.en.hisupplier.com
Colour Separation // Separating a picture by colors in order to make negatives and plates for color printing. The fourcolor process requires four separations: cyan, magenta, yellow and black (CMYK).
www.commons.wikimedia.org
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Die & Die Cut // A die is a specialized tool used in manifacturing industries to cut or shape material using a press. Like molds, dies are generally customized to the item they are used to create. Products made with dies range from simple paper clips to complex pieces used in advanced technology. www.echocartons.com.au
Digital printing // Methods of printing from a digital based image directly to a variety of media. It usually refers to professional printing where small run jobs from desktop publishing and other digital sources are printed using large format and/or high volume laser or inkjet printers. www.accuprintllc.com
Digital Proofing // A digital proof is a color prepress proofing method where a job is printed from the digital file using inkjet, colour laser, dye sublimation, or thermal wax print technologies to give a good approximation of what the final printed piece will look like.
www.makakmedia.co.uk.com
Foil Emboss // Combination of foil stamping application of foil with heat and embossing creating a raised impression that results in a raised and foil stamped image is described as foil embossing.
www.embossedsealsandembossers.com
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glossary Crop Marks // Crossed lines placed at the corners of an image or a page to indicate where to trim it are known as crop marks. Crop Marks may be drawn on manually or automatically applied with some desktop publishing software programs.
Image courtesy of Can Meric
Cutting Forme // Cutting formes are the metal forms used to score and shape paper or cardboard. A cutting forme is like a printing forme, but instead of engravings and types it has cutting rules. Once mounted in a press a cutting form will cut and crease the paper instead of printing on it.
Image courtesy of Can Meric
Gate Fold // A gatefold is a type of fold used for advertising around a magazine or section, and for packaging of media such as vinly records.
www.freepatterns.com
GSM // The unit of measurement for paper weight (grams per square meter).
www.deansart.com
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Fold Marks // With printed matter, markings indicating where a fold is to occur, usually located at the top edges.
Image courtesy of Can Meric
Four Colour Printing // A technique of printing that uses Cyan, Magenta, Yellow and Black to simulate full-colour images.
www.gallpen.com
Pantone Matching System // The accuracy of color is critical in design. Because what you see on your monitor is never what will appear on a printed sheet, designers need a standardized color key.
www.tima.toyoink.com
Paper Sizes // Many paper size standards and conventions have existed at different times and in different countries, but today there is one widespread international ISO standard (including A4, B3, C4, etc.), versus a localized standard used in North America (with: letter, legal, ledger, etc.). The paper sizes affect writing paper, stationary, cards, or some printed documents.
A4 A3 A4 A5
210 x 210
DL
A6 BC
Image courtesy of Can Meric
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glossary Halftone // A term referring to the reprographic technique that simulates continuous imagery through the use of dots, varying either in size, in shape or in spacing. Halftone can also be used to refer specifically to the image that is produced by this process. www.psdgraphics.com
Halftone Screen // The term Halftone Screen refers to the pattern of dots of varying sizes applied to an image of varying tones, or same sized dots applied to a tint of colour, when output to - film for the printing processes or laser printed artwork etc. www.coolconservation-us.org
Imposition // Imposition is one of the fundamental steps in the prepress printing process. It consists in the arrangement of the printed product’s pages on the printer’s sheet, in order to obtain faster printing, simplified binding and less waste of paper. www.helpadobe.com
Impression Cylinder // Cylindrical device on a printing press that presses the paper against the printing plate (direct printing), or against the blanket (offset printing).
www.crabtreeofgateshead.com
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Perforation Mark // A hole or series of holes punched or bored through something, especially a hole in a series, separating sections in a sheet or roll.
www.flickr.com.com
Process Colour: In printing, the subtractive primaries: yellow, magenta and cyan, as well as black in four-color process printing.
www.plaintalkprint.com
Registration Marks // Crosses or other marks used by the artists and printers as aids to the accurate positioning of two or more printings on a single sheet of paper.
www.creativedesignscakes.com
Saturation // The intensity of a specific hue.
Image courtesy of Can Meric
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glossary Screen Angle // In offset printing, the screen angle is the angle at which the halftones of a separated color is outputted to a lithographic film, hence, printed on final product media.
www.qualityinprint.blogspot.com
Spot Colour // In offset printing, a spot color is any color generated by an ink (pure or mixed) that is printed using a single run.
www.colourtone.co.uk
Trim size // The final size of a printed page after excess edges have been cut off is the trim size. Crop marks to indicate where to cut are printed in the edges that are then trimmed after printing.
www.qpjoplin.com
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minor printing die cutting
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