Photopolymerizable oligomer

Claim 2

A polymerizable oligomer of the formula ##STR13## 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 ##STR14## 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.

Claim 3

The oligomer of claim 1 wherein E is selected from the class consisting of acryloyloxyalkoxy, methacryloyloxyalkoxy, vinylalkoxy, and allyloxy groups, D is the residue of a diisocyanate, A is selected from the group consisting of ##STR15## m is an integer of from 1 to 6 inclusive.

Claim 4

The oligomer of claim 2 wherein E is selected from the class consisting of acryloyloxyalkoxy and methacryloyloxyalkoxy, and said oligomer has 2 to 4 ethylenically unsaturated groups selected from the class consisting of acryloxy and methacryloxy.

Claim 5

The oligomer of claim 3 wherein R is the residue of a polyesterpolyol having a hydroxy equivalent weight between 90 and 4,000.

Claim 6

The oligomer of claim 1 wherein said oligomer is represented by the formula: ##STR16## wherein E is an ethylenically unsaturated free radical polymerizable group selected from acryloyloxyalkoxy and methacryloyloxyalkoxy, D is the residue of a diisocyanate having its two isocyanate groups reacted to form ##STR17## bonded to E and R 1 , R 1 is the residue formed by the removal of active hydrogen atoms and hydroxyl groups from oligomeric Ω-hydroxy carboxylic acids or the residue formed by the removal of active hydrogen atoms and hydroxyl groups from oligomeric diols, R 2 is the residue of an aliphatic polyol having the formula R 5 (OH) a+b after removal of a+b hydrogens from hydroxyl groups and having a valence of a+b, or the residue of an aliphatic polyol having the formula ##STR18## after removal of (a+b-1) hydrogens from hydroxyl groups and R 5 is the residue of an aliphatic polyol radical formed by having the OH groups of the polyol removed therefrom and having 3 to 10 valences substituted with OH groups, R 3 is the residue formed by removal of two ##STR19## from a dicarboxylic acid, a is a number having an average value of from 2 to 20, and b is a number having an average value of from 0.3 to 10, wherein the molecular weight of (R 1 a R 2 --R 1 ) b is between 200 and 5,000.

Claim 7

The oligomer of claim 1 wherein said oligomer is represented by the formula: ##STR20## wherein R 3 is the residue formed by the removal of two ##STR21## from a dicarboxylic acid, R 4 is H or CH 3 , c is 2 to 5 inclusive, p is a number average value of from 2 to 7.7, q is a number average value of from 0.3 to 4, R 6 is the residue formed by the removal of two isocyanate groups from a diisocyanate, and R 7 is an organic polyol radical which is the residue of an organic polyol with at least three hydroxyl groups removed therefrom and having a molecular weight of from 90 to 10,000.

Claim 8

The oligomer of claim 1, wherein said oligomer is of the formula ##STR22## wherein R 3 is the residue formed by removal of two ##STR23## from a dicarboxylic acid, R 4 is H of CH 3 , R 6 and R 8 are independently the residues formed by the removal of two isocyanate groups from a diisocyanate, di is 1 to 6 inclusive, e if an average value of 0.5 to 5 inclusive R 9 is an alkanepolyol radical having a valence of h+1 that is the residue of an alkanepolyol having h+1 hydroxyl groups removed therefrom, said alkanepolyol having a molecular weight of from 100 to 10,000, f is an integer of 1 to 6, and h is an integer of 2 to 8.