| Abstract: | Photocrosslinkable polymer is prepared from amorphous poly(methyl vinyl ketone) (A-PMVK) obtained by anionic polymerization of methyl vinyl ketone. The reaction of A-PMVK with cinnamoyl chloride proceeds in pyridine at 50°C. The photosensitivity of the polymer obtained is measured by infrared and Ultraviolet photometry. The polymer is of a crosslinkable type and forms cyclobutane linkage by ultraviolet irradiation. The polymer is coated on a lithographic aluminum plate and exposed to arc and high-pressure mercury lamps. Development is with benzene, and standard inking by lithography is applied. The imaging area on the plate is stable and harder than poly(vinyl cinnamate), due to intra- and intermolecular cyclization of the main chain. Many good reproductions are produced in the lithographic proofing machine. The photosensitive polymer obtained by A-PMVK is very useful in relief plates requiring etching. |
