EP 0408097 B1 19930901 - TANNING PROCESS OF HIDES
Title (en)
TANNING PROCESS OF HIDES
Publication
Application
Priority
FR 8909655 A 19890710
Abstract (en)
[origin: EP0408097A1] The invention relates to a process for tanning acidified wet raw hides. This process consists (a) in preparing a water-insoluble organic liquid bath, (b) in suspending in this bath an inorganic tanning agent based on a metal compound, especially a chromium salt or complex, (c) in adjusting the degree of hydration of the hides above a minimum threshold of 200% (weight of water added to the dry weight of hides) and below a maximum threshold corresponding to the limit of retention of water in the hide, (d) in bringing the hides thus hydrated into contact in the organic bath containing the tanning agent for a period of at least 4 hours and in slowly introducing a base into the bath so as gradually to raise the pH of the water retained in the hides to a final value of between a minimum threshold of 3.9 in the case of a chrome tanning agent, and a maximum threshold of 4.4 in the case of this chrome agent, and (e) in removing the hides from the bath and leaving them to rest for at least 24 hours. The process of the invention makes it possible to obtain at the same time a complete exhaustion of the tanning bath, an absence of release of tanning agent in the subsequent finishing operations and a leather of good quality.
IPC 1-7
IPC 8 full level
C14C 3/08 (2006.01); C14C 3/04 (2006.01); C14C 3/06 (2006.01)
CPC (source: EP KR)
C14C 3/04 (2013.01 - EP); C14C 3/06 (2013.01 - EP); C14C 9/04 (2013.01 - KR)
Designated contracting state (EPC)
AT BE DE ES FR GB GR IT NL SE
DOCDB simple family (publication)
EP 0408097 A1 19910116; EP 0408097 B1 19930901; AT E93898 T1 19930915; BR 9003194 A 19910827; CA 2020548 A1 19910111; CN 1049526 A 19910227; CS 276444 B6 19920513; DD 296506 A5 19911205; DE 69003040 D1 19931007; ES 2045762 T3 19940116; FR 2649413 A1 19910111; FR 2649413 B1 19930528; JP H03129000 A 19910531; KR 910003119 A 19910226; MA 21899 A1 19910401; PT 94631 A 19910320; PT 94631 B 19960131; TR 25083 A 19921101; YU 131890 A 19920720
DOCDB simple family (application)
EP 90201637 A 19900622; AT 90201637 T 19900622; BR 9003194 A 19900705; CA 2020548 A 19900705; CN 90104521 A 19900710; CS 338390 A 19900709; DD 34264290 A 19900710; DE 69003040 T 19900622; ES 90201637 T 19900622; FR 8909655 A 19890710; JP 18036990 A 19900707; KR 900010409 A 19900710; MA 22168 A 19900706; PT 9463190 A 19900709; TR 67790 A 19900730; YU 131890 A 19900709