A process for the production of leather

The present invention relates to a process for the production of leather, comprising at least two of the following steps A) to D): A) Use of one or more polyelectrolytes in the production of semi-finished products or intermediate products, which comprises adding to (of one or more polyelectrolytes (in at least one of the steps a) d) (A) together with 0 to 1.5 wt .-% lime, based on the salted weight, immediately before or during liming, (B) before or during the deliming, (C) prior to or during the pickling, (D) together with a total of 0 to 3 wt .-% alkali metal or alkaline earth metal salt, based on the pelt weight, immediately prior to or during pickling; B) treatment of the hides in the lime in aqueous liquor containing one or more compounds of general formula B.1 or their corresponding alkali metal, alkaline earth metal, ammonium or phosphonium salts, where the variables R C) the use of degreasing agents of the general formula C.1 for degreasing pelts, hides, or other intermediates and semi-finished products in the production of leather, wherein the variables n and R D) tanning using a tanning agent which can be produced by reacting at least ...