Process for the production of water-soluble powders or concentrated solutions of cationic dyes.

摘要

Process for the preparation of a cationic dye in the form of a water-soluble solid or a concentrated solution characterized by (a) preparing a cyanate of a cationic dye (b) isolating the dye cyanate (c) reacting the dye cyanate with an organic acid to produce a solution of the cationic dye salt of the organic acid, and optionally (d) converting the solution into a solid form. The invention includes a dyebath prepared from such a cationic dye, a method of dyeing or printing polyacrylonitrile, acid modified esters or polyamides using such a cationic dye and polyacrylonitrile, acid modified polyesters or polyamide fibres or fabrics dyed or printed with such a cationic dye.