Lithography in the minds of most people is a method of reproducing a photograph or artwork by means of a halftone screen. The screen, usually no finer than 400 lines per inch reproduces the image by varying degrees of density through control of the dot size. With screenless printing the image is reproduced without the screen, resulting in much better detail. The purpose of this thesis is to determine what type of plate material will work best with the "Association Product Coating", since the ST Sumner Williams plate that worked well with this coating is no longer produced. The criterion for a good plate is that it produce a full range of densities and run cleanly. This study is to determine whether a finely grained plate such as the brush grain, is the plate to use with the coating. Testing was done at different coating concentrations, different exposure times with different plate materials, and with different concentrations of prime coats. It was also theorized that perhaps the sensitizer had something to do with how the coating performed. The concentra tion of the sensitizer was varied in each test to see how much of a change there was. The test did prove that the coating worked with the finer grained plates, and that prime coats would reduce the amount of scrumming on the plate. It was also found that a one percent concentration of sensitizer worked the best.
Library of Congress Subject Headings
Printing plates--Testing; Plate-printing
Department, Program, or Center
School of Print Media (CIAS)
Martin, Stephen E., "Plate stability in screenless printing" (1980). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus