GB723719A - Disazo dyestuffs and their chromium complex compounds - Google Patents

Abstract

The invention comprises dyestuffs of formula <FORM:0723719/IV (c)/1> where A-N=N- is a radicle of a diazo component of the benzene or naphthalene series containing a sulphonic acid group, C is a coupling component which is a hydroxynaphthalene, a 1-aryl-5-pyrazolone, an acetoacetarylamide or a substitution product thereof being free from sulphonic and carboxylic acid groups and being coupled in 2-position to an OH-group, one of the radicles X, attached to benzene nucleus B which may carry other substituents, is OH and the other H, and the chromium complex compounds of the dyestuffs. The dyestuffs are obtainable by coupling diazotized dyestuffs of formula <FORM:0723719/IV (c)/2> where B bears an OH group in o-position to NH2, with the appropriate component free from sulphuric or carboxylic acid groups. The starting aminomonoazo dyestuffs may be made by coupling a diazo component of the benzene or naphthalene series containing a sulphonic acid group, with a 2-acylamino-1-hydroxybenzene and saponifying the acyl-amino group specified diazo components being 1-aminobenzene-2,3- and 4-sulphonic acid, 1-amino-4 - methylbenzene - 2 and 3 - sulphonic acid, 1 - amino - 4 - chlorobenzene - 2 - sulphonic acid, 1 - aminonaphthalene - 4-, 5-, 6- and 7-sulphonic acid and mixtures of the 6 and 7 acids and 2-aminonaphthalene-6- and 8-sulphonic acid. Chroming may be effected either in substance or on the fibre and the dyestuffs thus obtained give brown to olive shades on animal or polyamide fibres. Before chroming animal fibres are dyed red shades. Animal fibres may be dyed from neutral to weakly acid baths. In examples 1-aminobenzene-4-sulphonic acid --> 2 - acetylamino - 1 - hydroxybenzene is saponified, diazotized and coupled with (1) 2-hydroxynaphthalene and chromed in (2); (3) is similar to (1) and (2) except that 1-aminobenzene-2-sulphonic acid optionally containing a 4-CH3- or Cl-substituent is used; in (4) 1-aminonaphthalene-4- or -5-sulphonic acids --> 2-acetylamino - 1 - hydroxybenzene are saponified, diazotized and coupled with 2-hdyroxynaphthalene, acetoacetanilide, 1 - acetylamino-7-hydroxynaphthalene or 1-(31-nitrophenyl)-3-methyl-5-pyrazolone and after chromed in substance or on the fibre; (5) 1-aminonaphthalene-4-sulphonic acid --> 2-acetylamino-4-methyl-1-hydroxybenzene is saponified, diazotized and coupled with 2-hydroxynaphthalene and after-chromed in substance or on the fibre; and in (6) the aminoazodyestuff of (1) is diazotized and recycled with carbomethoxy-1-amino - 7 - hydroxynaphthalene and after chromed in substance or on the fibre.