NON-METAL TANNING PROCESS

摘要

Tanned leather, skin or pelt is produced by non-metal tanning, comprising the step of tanning a bated hide, skin or pelt with a tanning agent (A), the tanning agent (A) being at least a mixture of compounds of formula (I) and formula (II), wherein Hal signifies fluorine or chlorine, R1 signifies hydrogen, C1-8-alkyl or an alkyleneoxy radical of formula (III), - (- C2-3 alkylene - O -)q - H (III) R2 signifies a) phenyl, mono- or di-substituted with SO3M or COOM and optionally substituted also with hydroxyl or C1-4-alkyl or C1-4alkoxy, or b) naphthyl, mono- or di- or tri-substituted with SO3M and optionally substituted also with hydroxyl, or c) C1-8-alkylene, substituted with (S03M) or (COOM), or d) a radical of formula (IV), - (- C2-3 alkylene - O -)p - Y (IV) e) or a radical of formula (IVa), -(C2-3alkylene - O)p -C2-3 alkylene - SO2CH2 CH2O -Y (IVa) m signifies 1 or 2, P signifies 0 or 1, Y signifies hydrogen or -SO3M, q is of from 1 to 10, M signifies hydrogen or an alkali metal cation or an ammonium cation, the ammonium cation being a protonated tertiary amine or a quaternary ammonium cation, R3 signifies hydrogen or chlorine, in a tanning bath, the tanning bath having a pH of from 6 to 10 at the beginning of tanning step.