Carboxyfunctional crosslinker for epoxyfunctional powder coating binder

摘要

A polycarboxylic acid mixture (I) that is solid below 40 deg. C and liquid above 160 deg. C comprises at least two polycarboxylic acids having up to 20C atoms with a melting point above 95 deg. C with at least 5 wt.% of the polycarboxylic acid having the lowest melting point and at least 10 wt.% of the polycarboxylic acid having the highest melting point corresponding to at least 5 wt.% of the mixture. - Independent claims are included for: - (1) a thermally curable powder coating (II) comprising a binding agent component containing carboxylic-reactive groups, the polycarboxylic acid mixture (I) as a cross-linking component and optionally known processing aids and additives with the proviso that the ratio of carboxylic-reactive groups to carboxylic acid groups is 1 : (0.7 to 1.5); and - (2) a substrate coated with the powder coating (II)