Economy chrome tanning process with aldehyde-acids and keto-acids

US4715861A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Werner Lotz · Niedernhausen, DE
• Karlheinz Fuchs · Brechen, DE
• Siegmund Haller · Kelkheim, DE

Key dates

• Filing date: May 8, 1986
• Grant date: Dec 29, 1987
• Expiry date: May 8, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C14C3/06
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Economy chrome tanning process wherein the pelts are pretreated before the tanning with 0.1 to 2% of an aldehyde- or keto-acid, preferably with glyoxylic acid or pyruvic acid, and are then tanned by customary methods. In this pretreatment, which is preferably carried out in the pickle, the tanning requires a chromium supply of only 1.25 to 1.5% of Cr.sub.2 O.sub.3 on weight of pelt. Despite this reduced amount of chrome tannin the results obtained are boil-resistant leathers with uniform chromium distribution, excellent color levelness and very good physical properties.