摘要 |
Textile materials of natural polyamides or nylons, dyed with a dye containing acid groups, are after-treated with a dilute aqueous solution of a cationic condensate which is obtained by reaction of (a) piperazine or a derivative of piperazine with (b) a bifunctional crosslinking agent, such as an epihalohydrin, in a molar ratio of from 1:0.5 to 1:1.1, and quaternization of the condensate with benzyl chloride, from 0.15 to 1.0 mole of benzyl chloride being employed per equivalent of nitrogen in the component (a) during the quaternization. This after-treatment improves the wetfastness of the dye. |