Dressing leather or polyurethane leather with co-polyamide - derived from di:amine adipate and piperazine decane-di:carboxylate-azelate

摘要

The parent patents concern copolyamides (I), with K values of 35-70 (1% soln. in 96% H2SO4 at 20 degrees C), obtd. by melt condensn. at 180-300 degrees C from 5-18 (wt.%)% hexamethylene diamine adipate (II) and 95-82% salt (III) of piperazine and mixts. of decane-1,10-dicarboxylic acid and azelaic acid in 70:30 to 95:5 molar ratio, opt. in the presence of traces of monocarboxylic acid as mol.wt. regulator, according to DT 26 30 114, or from salts (IV) of adipic acid with a 5-20, pref. 6-15C (cyclo)aliphatic prim. diamine instead of (II) according to DT 28 00 149. According to DT 28 00 149, (I) is used for dressing artificial leather with a plasticised PVC surface. Improvement is that (I) is used for dressing leather or artificial leather with a polyurethane surface. (I) forms stable solns. in the usual solvent mixts., adheres firmly and permanently to the surface, has good feel, gloss and mechanical properties and retards plasticiser and dyestuff migration.