New hydroxy glycidyl ester(s) - and their reaction prods. with isocyanate contg. cpds., used as crosslinking agents in powder coatings

摘要

A hydroxyglycidyl ester of formula (1) or (2) is new. R1 = OH, 1-20C alkyl contg. OH; R2, R3 = H, 1-10C alkyl; R4-R6 - H, 1-4C alkyl; R1 and R2 together may form a 4-10C aliphatic or aromatic ring contg. OH. R7 = 1-4C alkyl contg. OH; R8 = a gp. (i); R9-R11 = H, 1-4C alkyl. The prepn. of (1) and (2) where (i) a hydroxyacid or hydroxyalkyl ester is saponified with lye (ii) the prod. of (i) is reacted with epichlorohydrin and their use are claimed. The reaction prod. of an isocyanate-contg. cpd. and (1) or (2) and its use are claimed. A powder coating based on (A) a carboxyl-functional polyester (B) an epoxy-functional crosslinking agent which is the reaction prod. of (a) an isocyanate-contg. cpd. (b) a hydroxyglycidyl ester of formula (1) or (2). Use of the above powder coating and a wholly or partly coated substrate are also claimed. Solvent- or water-based coatings based on reaction prods. of (1) and (2) and their use are claimed.