Tfl Ledertechnik Gmbh

Jon Louis McHugh

Jens Fennen

Campbell Thomas Page

Tanned leather is (a) pretreated in an aqueous and alkaline medium either with ammonia, primary amines or a mixture of ammonia and primary amines and then with a polyfunctional organic compound containing at least one aldehyde group as a functional group, or (b) in an aqueous and acidic medium with a polyfunctional organic compound and then ammonia, primary amines or a mixture of ammonia and primary amines, and (c) then dyed in an aqueous and alkaline medium with a water-soluble dye containing at least one functional group which is capable of reacting with one of the functional groups of the organic compound, forming a covalent bond. A tanned and dyed leather is obtainable with a high color intensity, outstanding wet fastness and excellent grain tightness, wherein the dye is permanently and covalently bonded to the leather via a bridging group, preferably in the region of the surface, and the bridging group is essentially bonded to the leather via &#x2014;N&#x2550;CH&#x2014; groups.

Growing community of inventors

Greensboro, NC, United States of America

Jon Louis McHugh