METHOD OF PREPARING LEATHER-WORKING POLYMER PRODUCTS Russian patent published in 2002 - IPC

FIELD: polymer production. SUBSTANCE: polymeric azo dyes applicable for leather and fur working are prepared by azo coupling of polyhexamethyleneguanidine with diazo component selected from group including sulfanilic acid, alpha-naphthylamine, p-nitroaniline, 2,4-dinitroaniline, and naphthionic acid, followed by subjecting azo compound thus obtained to complexing with one of the following transition metal cations: Ni(2+), Co(2+), Cu(2+), Cr(3+), and Al(3+). EFFECT: increased resistance of coloration as well as leather and skin tissue of fur against physico-mechanical attacks.