Dyeing of grain leather

Abstract

A process for dyeing grain leather with anionic dyes under the conventional conditions for exhaustion methods, in the presence of two specific surfactants. The combined use of the two surfactants results, in the case of cationically tanned (essentially mineral-tanned) leather, in an improvement in the levelness and dye penetration and in the case of anionically tanned (synthetics-tanned or vegetable-tanned) or retanned leather, in an increase in depth of the color. The two surfactants are (a) an aliphatic alcohol of 9 to 24 carbon atoms oxyethylated with from 3 to 120 ethylene oxide units and (b) an aliphatic amine of 8 to 20 carbon atoms oxyethylated with from 6 to 80 ethylene oxide units, and they are used in a weight ratio of a:b of from 1:4 to 4:1 and in a total amount of from 0.3 to 3%, based on shaved weight.

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