| 摘要 |
A photopolymerizable composition useful on printing plates comprises (1) 10% to 60% by weight of an organic film forming polymer, (2) 10% to 60% by weight of a free radical polymerizable monomer having at least one ethylenically unsaturated group, (3) 0.1% to 12% by weight of a photoinitiator system, and (4) 10% to 60% by weight of an oligomer of the formula <IMAGE> wherein E is an ethylenically unsaturated, free radical polymerizable group, D is the residue of a polyisocyanate having at least two of its isocyanate groups reacted to form <IMAGE> groups bonded to E and R, R is the residue of a polyol having at least a + b hydroxyl groups, formed by removal of hydrogen from the hydroxyl groups, said polyol having a number average molecular weight between 90 and 10,000, A is a carboxylic acid containing group, a is 2 to 20, and b is 0.3 to 10. The invention also relates to a polymerizable oligomer of the formula given in (4) above. |
