GB1469933A - Pretanning process - Google Patents

Abstract

1469933 Pre-tanning process AFRICAN TERRITORIES WATTLE INDUSTRIES FUND Ltd 3 March 1975 [3 Dec 1973] 55977/73 Addition to 1394684 Heading C6C Hides or skins are tanned by treating wet limed pelts, in the absence of bulk liquor, with a solid, water-soluble acidic salt, at a pH of not less than 3, and completely tanning the treated pelts with a tanning agent. The acidic salt may be added as such in solid form to the wet limed pelt or it may be formed in situ on the wet limed pelt by treating a non-acidic solid salt applied thereto with an acid. The salt used may be an inorganic sulphate and/or chloride e.g. sodium or magnesium sulphate or sodium chloride. A phosphate salt may be additionally used. The wet limed pelts may be simultaneously treated, in the absence of bulk liquor, with an inorganic sulphate and with a tanning agent. The tanning agent may be a vegetable tanning agent used to provide either a complete tannage or a preliminary tannage prior to a further vegetable tannage or a final chrome tannage.