Photosensitive polymer composition and negative working photosensitive element containing three photocrosslinkable polymers

摘要

A photosensitive composition can be used to prepare negative-working photosensitive elements such as lithographic printing plates. The composition includes a first photocrosslinkable aromatic resin having photocrosslinkable groups and a number average molecular weight of at least about 1500. Also included is a polymerizable monomer, a photocrosslinkable polyester, a photocrosslinkable copolymer of styrene and maleic anhydride, and a photoinitiator. The photocrosslinkable resins are present at a total weight ratio to the polymerizable monomer of at least 1.5:1.