Photopolymerizable composition containing ethylenically unsaturated oligomers

A photopolymerizable composition comprising

• (1) 10% to 60% by weight of an oligomer of the formula ##STR14## 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 ##STR15## groups bonded to E and R, R is the residue of a polyol having at least a +b hydroxyl groups, the residue 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 a number having an average value between 2 and 20, and
• b is a number having an average value between 0.3 and 10,
• (2) 10% to 60% by weight of an organic film forming polymer having a molecular weight of at least 6,000,
• (3) 10% to 60% by weight of a free radical polymerizable monomer having at least one ethylenically unsaturated group, and
• (4) 0.1% to 12% by weight of a photoinitiator system capable of initiating free radical polymerization upon absorption of electromagnetic radiation.