Abstract

With strict discharge limits on chromium in tannery effluents, there is high interest in chrome alternatives. A sequential tanning procedure using synthetic resins (from urea or dicyanidiamide, phenolic compounds, sulphonated phenolic compounds, and formaldehyde) followed by masked aluminium or titanium salt has been developed. The method produces white full leather with shrinkage temperature up to 100°C. This leather needs more fatliquor but withstands severe dye bath conditions.