Patent GB-602254-A (GB)
Title: Manufacture of polyazo-dyestuffs capable of being metallised
IPC: C09B35/46
Filed: 1945-05-24
Abstract: Polyazo dyestuffs are manufactured by converting a primary disazo dyestuff of the general formula <FORM:0602254/IV (c)/1> (wherein one X represents a sulphonic acid group and the other a hydrogen atom, Y a sulphonic acid group or a hydrogen atom, Z a nitro or acylamino group, and Ar1 and Ar2 aromatic residues of the benzene series at least one of which contains a group capable of leading to the formation of metal complexes, e.g. a carboxyl or alkoxy group in o-position to the azo group or to the group Z, and both of which contain a substituent Z) into the corresponding diaminodisazo dyestuff by reduction or hydrolysis of the substituents Z, tetrazotizing and coupling with two molecular proportions of an end component of the naphthalene series which contains a hydroxy group and may also contain azo groups, or with one molecular proportion of each of two different end components of this kind, e.g. a - or b -naphthol or their substitution products capable of coupling, such as their sulphonic or carboxylic acids, or aminonaphtholsulphonic acids or their N-acyl, N-alkyl or N-aryl derivatives or monoazo dyestuffs derived therefrom and capable of coupling, such as those obtained by acid coupling of diazo compounds with aminonaphtholmono- or di-sulphonic acids.  Alternatively, when one Z represents a nitro group and the other an acylamino group, one of them is first converted by reduction or hydrolysis into an amino group which is diazotized, the diazodisazo compound is coupled with an end component of the kind defined, then the second substituent Z is converted by hydrolysis or reduction into an amino group, which is diazotized and the diazo compound is coupled with the same or a different end component of the kind defined.  The products dye cellulose fibres, such as cotton, linen, ramie, hemp or jute and fibres (e.g. staple fibres or artificial silk) of regenerated cellulose, in greenish to reddish grey shades by the usual methods for direct dyestuffs, advantaneously with after-treatment with an agent yielding metal, e.g. treatment in the dyebath or in a separate bath with copper salts (e.g. copper sulphate or acetate) in a neutral or weakly acid medium or with copper compounds stable to alkali (e.g. those obtained by the reaction of copper sulphate with sodium tartrate) in a bath rendered alkaline with sodium carbonate, or treatment with agents yielding other metals (e.g. salts of chromium, cobalt, manganese or nickel) or mixtures of heavy metal salts.  The dyestuffs may also be converted in substance into complex copper compounds by treatment with agents yielding copper in an acid or neutral bath or a bath rendered alkaline with ammonia; or a dyestuff capable of being metallized twice may be treated with only one mol. of an agent yielding copper, the material dyed with the incompletely coppered compound and the dyeing after-treated with an agent yielding copper or another metal. In examples: (1) H-acid is coupled in acid solution with diazolized p-nitraniline and in alkaline solution with diazotized 5-nitro-2-aminobenzoic acid, and the resulting disazo dyestuff is reduced with sodium sulphide, tetrazotized and coupled with two molecular proportions of one of the monoazo dyestuffs 1 - amino - 4 - hydroxybenzene - 3 - car - boxylic acid, 2-aminobenzoic acid or 5-chloro-or 5-nitro-2-aminobenzoic acid --> (acid) J-acid, or 5-nitro-2-aminobenzoic acid --> (acid) H-acid; (2) K-acid is coupled in acid solution with diazotized 2-acetylamino-5-aminobenzoic and in alkaline solution with diazotized 4-acetyl-amino-2-amino-1-methoxybenzene, and the resulting disazo dyestuff is hydrolysed with aqueous caustic soda, tetrazotized and coupled with two molecular proportions of benzoyl-Y-acid; the product is coppered by boiling with copper sulphate solution; (3) H-acid is coupled in acid solution with diazotized 5-nitro-2-aminobenzoic acid and in alkaline solution with 4-acetylamino-2-amino-1-methoxybenzene, the resulting disazo dyestuff is reduced, diazotized and coupled with 1 : 2-hydroxynaphthoic acid, and the product is hydrolysed, diazotized and coupled with the monoazo dyestuff 1-amino-4-hydroxybenzene-3-carboxylic acid --> (acid) J-acid; (4) the dyestuff 5-nitro-2-aminobenzoic acid --> (acid) H-acid is coupled (alkaline) with diazotized 5-nitro-2-amino-1-methoxybenzene, and the resulting disazo dyestuff is reduced, tetrazotized and coupled with two molecular proportions of 1 : 2-hydroxynaphthoic acid.  A table gives the properties of further dyestuffs, the following additional components being used: diazo components (Z-Ar1-NH2 or NH2-Ar2-Z): m-nitraniline, 5-acetylamino-2-aminobenzoic acid, 2-nitro-5-aminobenzoic acid, 2-acetylamino-5-amino-1-methoxybenzene, 2-nitro-5-amino-1-methoxybenzene and 5-nitro-2-amino-1 : 4-dimethoxybenzene; end components: b -naphthol, 2-naphthol-6-sulphonic acid, phenyl-J-acid and 2 : 3-hydroxynaphthoic acid.  Samples have been furnished under Sect. 2 (5) of the products obtained by reducing the dyestuff 5-nitro-2-aminobenzoic acid --> (acid) S-acid (alkaline) \sM 5-nitro-2-amino-1-methoxybenzene, tetrazotizing and coupling with two molecular proportions of (A) 1 : 2-hydroxynaphthoic acid, and (B) the monoazo dyestuff 1 - amino - 4 - hydroxybenzene - 3 - carboxylic acid --> (acid) J-acid.  The Specification as open to inspection under Sect. 91 comprises also the use of other end components containing hydroxy groups (including enolizable keto groups) and capable of coupling once, such as 3-methyl-5-pyrazolone, 1-phenyl-3-alkyl- (e.g. methyl-), -3-aryl- or -3-carboxy-5-pyrazolones, b -keto-carboxylic acid anilides or substitution products thereof (e.g. (aceto) acetic anilide) and salicylic acids or homologues thereof capable of coupling. Additional metal complex forming groups specified are substituted alkoxy groups and hydroxy groups.  This subject-matter does not appear in the Specification as accepted.