Process and agent for the single-bath reoxidation and soaping of vat or sulphur vat dyeings

摘要

The alkaline reoxidation of vat and sulfur vat dyes by means of hydrogen peroxide is difficult to control and to keep constant. By using agents which split off hypochlorite in the heat, for example sodium N-chloro-p-toluenesulfonamide, at pH values above 8 it is possible according to the invention even to reoxidize reliably combinations of these dyes having different oxidation behaviors. At the same time it became possible to combine the necessary soaping process with reoxidation.