Dyeing leather and fur brown with 1:2 chromium complex azo dye

摘要

Use of dyes (I) for colouring leather and furo is new (X is H, chloro or nitro; the sulpho gp. may be in ring A or B and the nitro gp. at the 4, 5 or 6 posn. of A. Ka is a cation). Esp. X is nitro; the other nitro is at 4-posn. and the sulpho at the 6-posn. of B. - (I) provide strong brown shades on leather with good fastness to light and wet treatment. Pref. they are formulated with at least one of orange, red or reddish brown; blue or violet; yellow or yellow-brown, or opt. yellow dyes. These mixts. provide almost all dark shades and tone-on-tone dyeing on different types of leather. (0/0) EPAB- EP-110822 B Use of dyes (I) for colouring leather and fur is new (X is H, chloro or nitro; the sulpho gp. may be in ring A or B and the nitro gp. at the 4, 5 or 6 posn. of A, Ka is a cation). Esp. X is nitro; the other nitro is 4-posn. and the sulpho at the 6-posn. of B. - (I) provide strong brown shades on leather with good fastness to light and wet treatment. Pref. they are formulated with at least one of orange, red or reddish brown; blue or violet; yellow or yellow-brown, or opt. yellow dyes. These mixts. provide almost all dark shades and tone-on-tone dyeing on different types of leather. - (17pp) USAB- US4507125 A Process for dyeing leather or furs comprises application of a 1:2-Cr complex dye of formula (I). In (I), X is Cl or NO2; the SO3H substit. is attached to ring A or B; the NO2 substit. in ring A is at position 4, 5 or 6 to the 1-OH-2-azo substits.; and M is a cation.