Global Patent Index - EP 0187473 B1

EP 0187473 B1 19890315 - PROCESS FOR TANNING HIDES

Title (en)

PROCESS FOR TANNING HIDES

Publication

EP 0187473 B1 19890315 (EN)

Application

EP 85308779 A 19851203

Priority

IT 2387084 A 19841203

Abstract (en)

[origin: EP0187473A1] The present invention relates to a process for tanning hides for vamps and peltry by means of ammonium titanyl sulphate. The process comprises the steps of treating the delimed hides in the presence of water with ammonium sulphate and naphthalene sulphonic acid; adding ammonium titanyl sulphate; optionally adding a complexing agent for tetravalent titanium ion; gradually making the bath alkaline by adding sodium sulphite and hexamethylenetetramine to obtain a pH in the hide from 4.0 to 5.0; removing the hides from the bath and pressing, shearing, and washing them with water; subjecting the hides to deacidification with an alkaline substance, in the presence of water and optionally in the presence of a complexing agent of tetravalent titanium ion, to obtain a pH of the hide from 5.0 to 6.5; washing the hides with water; and completing tanning, in the presence of water, with one or more synthetic tannins and/or polymeric material; and discharging the bath and greasing the hides according to known techniques. The complexing agent of the tetravalent titanium ion is preferably an alkaline citrate or tartrate, and it is added either during the tanning step with the ammonium titanyl sulphate or during the deacidification step or during both steps.

IPC 1-7

C14C 3/04; C14C 3/28

IPC 8 full level

C14C 3/04 (2006.01); C14C 3/28 (2006.01)

CPC (source: EP)

C14C 3/04 (2013.01); C14C 3/28 (2013.01)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0187473 A1 19860716; EP 0187473 B1 19890315; BR 8505963 A 19860819; DE 3568799 D1 19890420; ES 549493 A0 19870401; ES 8704548 A1 19870401; IT 1178688 B 19870916; IT 8423870 A0 19841203; IT 8423870 A1 19860603; TR 23452 A 19891229

DOCDB simple family (application)

EP 85308779 A 19851203; BR 8505963 A 19851128; DE 3568799 T 19851203; ES 549493 A 19851202; IT 2387084 A 19841203; TR 4821285 A 19851128