Abstract: A process for the production of leather, wherein tanned animal hides are treated in step (A) with an aqueous liquor which comprises (a) at least one copolymer obtainable by copolymerization of (a1) at least one ethylenically unsaturated C4-C8-dicarboxylic acid or at least one derivative of an ethylenically unsaturated C4-C8-dicarboxylic acid and (a2) at least one C8-C100-?-olefin and, if appropriate, hydrolysis and/or at least partial neutralization, (b) at least one paraffin which is liquid at room temperature, (c) at least one synthetic nonionic emulsifier, the aqueous liquor being free of silicones, and furthermore silicone-free aqueous formulations and their use.

Abstract: Water repellency is imparted to leather and fur skins by a process in which leather or fur skin is treated, before, during or after the retanning, with one or more formulations comprising from 1 to 30% by weight, based on the formulation, of a mixture of polysiloxanes comprising from 10 to 90% by weight, based on the mixture, of one or more carboxyl-containing polysiloxanes, from 90 to 10% by weight, based on the mixture, of one or more carboxyl-free polysiloxanes and from 3 to 25% by weight, based on the formulation, of at least one emulsifier.