Process

Page 1

Process Lithography Gravure Letterpress Flexography Screen printing


Lithography Lithography uses a smooth printing plate and functions on the basis that oil and water repel each other. Lithography printing is a process which the inked image from a printing plate is transferred on to a rubber blanket roller, which then presses against the stock. When the plate passes under the ink roller, non-image areas that have a water film repel the oily inks that stick to the image areas.

Ink rollers Water rollers

Water

Plate cylinder

Lithography reproduces good photographic work and fine line work on a variety of different stocks. The printing plates are easy to prepare and high speeds are achieved, which helps make it a low-cost printing method. Offset lithography is available in sheet-fed printing presses and continuous web presses. Sheet-fed presses are used for things such as flyers, brochures and magazines,things which have an end date and are short run, while web printing is used for highvolume print jobs such as newspapers, magazines and reports.

Offset cylinder

Stock

Impression cylinder


Printing cylinder

Gravure In gravure printing, the printing elements take the form of cells. The printed image is transferred to the cylinder with a diamond stylus using electromagnetic gravure process.

The cylinder is inked completely for the print run. Then a blade strips the excess ink off the surface of the form cylinder and the ink is left only in the indentation.

A rubberised roll presses the paper against the cylinder and the ink remaining in the cells is deposited directly onto the paper/stock. The blade is a thin, straight steel rule in gravure printing.

Stock

Blade Form cylinder

Ink


Letterpress

Ink roller

Letterpress is a method of relief printing, where a worker composes and locks movable type into the bed of a press, then the inked raised surface is pressed against a stock by a roller. Letterpress was the first commercial printing method and the source of many printing methods. The raised surface that is inked for printing may be made from single type blocks, cast lines or engraved plates. Relief printing methods can be identified by the sharp and precise edges to letter and their heavier ink borders. Letterpress printing remained the primary way to print and distribute information until the twentieth century, when offset printing was developed, which largely supplanted its role in printing books and newspapers. More recently, letterpress printing has seen a revival in an art form.

Stock

Printing plate


Flexography

Plate cylinder

Another method with the image is carried by surface differences in the plate is flexography. This process creates a rubber relief of the image, which is inked and pressed against the substrate.

Fountain roll

Developed for printing packaging materials, the process was traditionally a lower quality reproduction method, but it now competes with rotogravure and lithography, particularly as it can print on a wider range of substrates due to flexibility of its plate.

Stock Ink

Flexography is used for medium to large print runs, therefore you need to consider the print quantity of prints before you chose the process.

Anilox roll

Impression cylinder


Screen Printing Squeegee

Screen printing is a relatively low-volume printing method in which a viscous ink is passed through a screen. The screen are originally made from silk which that holds a design through exposing an image, which is then applied on to a substrate.

Although screen printing is a relatively slow, low-volume and expensive printing method, screen printing allows images to be applied to a wide range of materials and substrates, including cloth, ceramics and metals, which are unthinkable for other printing methods.

The ink applied onto the stock can also be white which other printers most other printing methods can’t do. Screen printing can also create certain effects which other print methods can’t, it is all physically done, a very hands on method of printing.

Ink

Screen

Stock



Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.