Tanning leather with tris(hydroxymethyl)phosphine or a salt or condensate thereof

摘要

A synergistic tanning composition comprises an aqueous solution of (A) tri (hydroxymethyl) phosphine (THP) or tetrakis (hydroxymethyl) phosphonium salt (THP salt) or a THP condensate, (B) a mineral tanning salt such as a titanium or zirconium salt and optionally a (C) synthetic tannin agent and/or non-ionic surfactant and/or a cationic surfactant.