Patent ID: 8084512

Claim:
A water soluble photosensitive polyimide polymer which is characterized in that it possesses the repeat units represented by formula (I): R 1 represents a tetra-valence organic group having 4 or more carbon atoms; R 2 is a three- or tetra-valence organic group, which is optionally substituted with carboxyl group; R 3 represents a two- to tetra-valence organic group; A represents OH or COOH group; R 4 and R 5 are the same or different, each represents an alkylene group having 1˜6 carbon atoms, an arylene group, arylalkylene group, arylene-oxy-alkylene group having 6˜20 carbon atoms; R 7 and R 8 are the same or different, each represents the group selected from a hydrogen, a halogen, a carboxyl, a linear or cyclic alkyl having 1˜20 carbon atoms, an aryl, alkylaryl, and arylalkyl having 6˜20 carbon atoms; R 9 represents a hydrogen atom or an alkyl group having 1-6 carbon atoms; x represents an integer of 1 or 2; y represents an integer of 0, 1 or 2; a, b and n each represents an integer equal to or greater than 1; m and k each represents an integer equal to or greater than 0]; wherein the above repeating units are in random or block arrangement.