Patent ID: 8679195

Claim:
A process for the production of tanned leather, skins or pelts 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 one compound of formula (I), wherein Hal is fluorine or chlorine, R1 is hydrogen, C 1-8 -alkyl or an alkyleneoxy radical of formula (Ia), —(—C 2-3 alkylene-O—) q —H (Ia) R2 is C 1-4 -alkyl or C 1-4 -alkoxy, m is 1 or 2, n is 0 or 1, q is from 1 to 10, M is hydrogen or an alkali metal cation or an ammonium cation, the ammonium cation being a protonated tertiary amine or a quaternary ammonium cation, in a tanning bath, the tanning bath having a pH of from 6 to 10 at the beginning of tanning step.