1,3-Benzenedicarboxylic acid polymer with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol, 1,6-hexanediol, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethylcyclohexane and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediol, acetone oxime-blocked