Te-Chung Chen

Abstract

Most people conceive of lithography as a planographic method of printing. In point of fact, only some of the original lithographic plates had truly planographic surfaces. Most lithographic plates used in industry today do not have the same material in the image and non-image areas, so they are called double-phase plates . Because of light undercutting and the roughness of the grain structure of the carrier, the use of conventional double-phase plates for fine image reproduction, where resolution is the main concern, has been limited. The purpose of this study was to determine the image formation mechanism of single-phase plates (i.e. plates with image and non-image areas on the same plane and made of the same material . ) by investigating the resolution performance of Association Product plates. There are good reasons to believe that Association Product plates give better resolution than conventional double-phase plates. A comparative study of the resolving power of Association Product plates and commonly used double phase plates provides information about the quantitative difference of resolution between these two types of plates. In choosing to study the image-forming mechanism from the coating variations point-of-view, it was hoped to arrive at a demonstrable independence of plate resolving power from plate coating thickness in the single-phase plate. Results of the experiment showed that coating thickness and grain structure of the plate base does not affect the resolving power of this type of plate. The main factor which directly affects the resolving power is the exposure time.

Library of Congress Subject Headings

Lithography--Metal plate processes; Lithography--Printing; Presswork (Printing)

Publication Date

5-1-1984

Document Type

Thesis

Department, Program, or Center

School of Print Media (CIAS)

Advisor

Silver, Julius

Comments

Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: Z252.5.L5C54 1984

Campus

RIT – Main Campus

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