A dynamic development which has sparked flexography is the introduction and use of photopolymer plates. These plates have simplified flexographic printing by reducing the amount of time and effort needed to prepare plates for press and makeready. An experiment was conducted to determine the effect of commonly used solvent mixtures on flexographic plates. The plates tested include those using natural rubber, Buna N, and various photopolymers. The experiment specifically studied change in hardness of these plate materials due to immersion in different solvent mixtures over time. Noticeable differances in the degree of softening of plates was observed after 24 hours of immersion. Differences in the degree of softening were found in the plates after soaking in different percents of solvents. It was also discovered what percents of different lactol spirits and normal propyl acetate added to alcohol would affect the plates the most. Further, these differences were detectable at different periods of time. Most plates softened with time. One plate softened to such a degree with the solvent of this experiment that it was difficult to determine which solvents had a significant effect. This, of course, is due to the fact that solvents compatible with this plate were not used in this experiment. All photopolymer plates performed poorly in acetates, but it would be possible to use acetates with these plates over short periods of time on small press runs. When using flexographic plates of the composition tested in this experiment it is recommended that the practitioner use less than five percent of lactol or ten percent normal propyl acetate for a minimum affect on these plates over a short period of time.
Print Media (MS)
Department, Program, or Center
Printing Industry Center (CIAS)
Jenkins, Jack, "The effects of common solvents on different types of flexographic printing plates" (1985). Thesis. Rochester Institute of Technology. Accessed from
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