Chromium free process for the tanning of hides
Patent 4960429 Issued on October 2, 1990. Estimated Expiration Date: 
March 9, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 9, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesLeather treating process Leather tanning process using aluminium (III) and titanium (IV) complexes Patent #: 4731089 InventorsAssigneeApplicationNo. 321006 filed on 03/09/1989US Classes:8/94.26, With organic material8/94.1RTREATMENT OF HIDES, SKINS, FEATHERS AND ANIMAL TISSUESExaminersPrimary: Lieberman, PaulAssistant: McNally, John F. Attorney, Agent or FirmInternational ClassesC14C 003/02C14C 003/04 Foreign Application Priority Data1988-11-17 ESAbstractA process for the tanning of skins applicable to lamb, goat, calf hides, or skins from other origins. The process is based in the previous modification of the collagen of the skin by covalent reaction with polyfunctional polymers with a high quantity of hydroxylic groups. The modification treatment may be carried out after bated skin or pickled skin has been previously depickled. After binding of the polymer, the reactivity of the skin substrate is modified whereby it will show a higher affinity for titanium salts, for example ammonium titanyl double sulphate, titanyl sulphate or any other soluble titanium compound. | |
