Method of increasing depth shade

Abstract

The invention relates to a method of increasing the depth of shade of dyed natural or synthetic polyamide fiber materials, which comprises treating the fiber material before, during or after dyeing with a liquor comprising a compound of formula (1) wherein R is halogen, C1-C12alkyl, C5-C24aryl, C6-C36aralkyl, —OR1, or —NR1R2, R1 and R2 being, each independently of the other, hydrogen, C1-C12alkyl unsubstituted or substituted by one or more hydroxy, amino, mercapto, carboxyl, sulfo, C1-C12alkylsulfonyl, C5-C24arylsulfonyl or C6-C36aralkylsulfonyl groups, C5-C24aryl unsubstituted or substituted by one or more hydroxy, amino, carboxyl, sulfo, C1-C12 alkylsulfonyl, C5-C24arylsulfonyl or C6-C36aralkylsulfonyl groups, or C6-C36aralkyl unsubstituted or substituted by one or more hydroxy, amino, carboxyl, sulfo, C1-C12alkylsulfonyl, C5-C24arylsulfonyl or C6-C36aralkylsulfonyl groups, X and Y are, each independently of the other, mercapto, —NR3R4 or —N+R3R4R5A−, wherein R3, R4 and R5 are, each independently of the others, hydrogen or C1-C12alkyl and A− is chloride, bromite, iodide, sulfate or methylsulfate, R6 and R7 are, each independently of the other, hydrogen or C1-C12alkyl, and x and y are, each independently of the other, a number from 2 to 12.

Dependencies are inferred from the claim text.