PRINTING What is a Printing and Publishing Industry

PRINTING

What is a Printing and Publishing Industry? The printing and publishing industry, defined broadly, includes firms whose business is dominated by printing operations such as platemaking, bookbinding, and publishers, whether or not they actually print their own material.

Types of Printing Industry • The industry is organized by the type of printing process used: ü Lithography ü Gravure ü Flexography ü Screen ü Letter press

The Fundamental Steps in the printing process are: 1. Imaging operations Composition & Typesetting Photographic negative or positive Transparency production The five printing technologies differ significantly in how the image is transferred from the image carrier to the substrate in the printing step.

Fundamental Steps in the printing process… 1. Imaging operations 2. Pre-press operations In Pre-press operations, an image carrier is produced that can transfer the ink in the image area and can repel the ink in the non-image areas.

Fundamental Steps in the printing process are: 1. Imaging operations 2. Pre-press operations 3. Post-press operations In the post-press step, the printed material may receive any one of numerous finishing operations e. g. cutting, folding, collating, binding, perforating, drilling etc depending on the desired form of the final operations.

LETTERPRESS PRINTING • The letters and designs to be reproduced are raised above the nonprinting areas of the press plate. • Using plates for the printing, ink is applied only to the raised areas, by means of inking rollers.

LETTERPRESS PRINTING Raised surface are the types set by hand or machine, engravings or plates of copper, zinc or other metal, wood, rubber, plastic or a combination of materials.

LETTER PRESS • Letterpress printing remained the primary way to print and distribute information until the twentieth century. • Letterpress printing is a printing technique which has been in use in the West since the 15 th Century, when it was used by Johannes Gutenberg to manufacture the Gutenberg Bible.

PLATEN PRESS • In Platen Press, paper is fed to a flat surface called a platen. The platen contacts the inked type form clamped against bed of the press. • It is used extensively in small printing jobs such as name cards, bill heads, forms etc…

FLAT-BED CYLINDER PRESS In Flat Bed Cylinder Press, paper is held on a cylinder by means of grippers and is rolled over the printing form locked on the flat bed. The printing form moves horizontally, and the paper revolves with the cylinder over the form.

ROTARY PRESS Rotary Press on which both paper and plates are on cylinders rolling against each other. The plates (stereotypes or electrolytes) are curved. Paper used for printing on a rotary press may be in sheets (sheet-fed press) or in rolls (web – fed press)

Letterpress Process: Inputs and Outputs Process Inputs Outputs Imaging Film Used film, old film Paper Scrap paper Cleaning solutions Rags with solvents Fixer May be volatile and contribute to emission Plate mold Used molds Plate developer solution Waste water solution Cleaning solutions Ink solvents lead to air emissions. Ink Waste ink hazardous to waste water. Paper & Adhesives Reject prints and edges from trimming. Plate making Printing Finishing

Types of Printing Industry

Lithography • Lithography is a chemical process. • Lithography depends on the principle that oil and water do not mix

Images (words and art) are put on plates which are dampened first by water, then ink. The ink sticks to the image area, the water to the nonimage area. Then the image is transferred to a rubber blanket, and from the rubber blanket to paper.

Gravure This uses almost exclusively electromechanically engraved copper image carriers to separate the image area from the non-image area. This image carrier is usually a cylinder. Ink is applied to the engraved cylinder, and the printing substrate is brought into contact with the cylinder with sufficient pressure.

Additional Stations for Multicolor Printing Dryer Impression roller Sheets Doctor blade Ink Fountain

Screen Printing • Unlike the impervious plates used in the other printing processes, the screen printing process uses a porous mesh. The mesh is stretched tightly over a frame, and stencil, which defines the image to be printed. • The major chemicals used are organic solvents, adhesives and inks. Screen printing is very versatile, and can be used to print on paper, plastics, glass, metals, textiles etc.