Patent GB-408497-A (GB)
Title: A process for producing fast tints on animal fibres
IPC: D06P1/62
Filed: 1933-08-14
Abstract: Acid wool dyes, dyeing with.--Animal fibres are dyed in fast shades by treatment in a bath containing a chromiferous azo dyestuff and an aromatic organic acid followed by development in a bath containing a mineral acid.  Alternatively, the whole or a portion of the mineral acid may be used in the bath containing the aromatic acid.  The latter may be added to the bath in the form of a salt.  Aromatic sulphonic, carboxylic or sulphocarboxylic acids may be used, including substitution products thereof, e.g. amino-acids, oxy-acids, amino-oxy-acids, halogenated acids, nitrated acids, w-benzylsulphuric acids of the type aryl-CH2SO3H, sulphamic acids of the type aryl-NH.SO3H and oxamic acids.  The following examples are specified: (1) Wool is entered into a bath at 60--70 DEG  C. containing benzenemonosulphonic acid and the chromium compound of the dyestuff 4-nitro-2-aminophenol-6-sulphonic acid --> acetoacetic anilide, the temperature is raised to the boil in \ba1/2\be hour, sulphuric acid is added, boiling is continued for 1--1\ba1/2\be hours and the goods are rinsed and dried to obtain full pure yellow dyeings; the benzenemonosulphonic acid may be replaced by benzenepolysulphonic acids, mono- or poly-sulphonic acids of the naphthalene or anthracene series, e.g. 1 : 5-naphthalenedisulphonic acid, or substitution products thereof, e.g. naphthylaminesulphonic or aminonaphtholsulphonic acids, arylcarboxylic acids, e.g. benzoic, oxybenzoic or phthalic acids and arylsulphocarboxylic acids, e.g. sulphosalicylic or sulphophthalic acids; (2) Wool is similarly dyed a full pure green with the chromium compound of the dyestuff 4-nitro-2-aminophenol - 6 - sulphonic acid --> 2 - amino - naphthalene; similar dyeings are obtainable with the chromium compounds of the dyestuffs 1 : 2 : 4-aminonaphtholsulphonic acid --> 1-(3<1>-sulphamido) phenyl-3-methyl-5-pyrazolone, 2 : 1 : 4 : 8-aminonaphtholdisulphonic acid --> 2-naphthol, 4-nitro-2-aminophenol-6-sulphonic acid or 2-aminophenol-4 : 6-disulphonic acid --> 1-phenyl-3-methyl-5-pyrazolone, or that from nitrated 1-diazo-2-naphthol-4-sulphonic acid and 2-naphthol; (3) Wool is entered into a bath at 60--70 DEG  C. containing sulphuric acid, 1 : 2 : 4-aminonaphtholsulphonic acid and the chromium compounds of the dyestuffs 2 : 1 : 4 : 8-aminonaphtholdisulphonic acid --> 2-naphthol, 1 : 2 : 4-aminonaphtholsulphonic acid --> 1 : 8-naphtholsulphamide, 1 : 2 : 4-aminonaphtholsulphonic acid --> 1-(3<1>-sulpho)phenyl-3-methyl - 5 - pyrazolone and 4 - nitro - 2 - amino - phenol - 6 - sulphonic acid --> 1 - phenyl - 3 - methyl-5-pyrazolone, the temperature is raised to the boil in \ba1/2\be hour and so maintained for 1--1\ba1/2\be hours and the goods are rinsed and dried to obtain full marine blue dyeings of good fastness to rubbing and to fulling; (4) Wool is entered into a bath at 60--70 DEG  C. containing sulphuric acid, 1 : 3-dioxybenzene-4-carboxylic acid, and the chromium compound of the dyestuff 4-nitro-2-aminophenol-6-sulphonic acid --> 1-phenyl-3-methyl-5-pyrazolone, the temperature is raised to the boil in \ba1/2\be hour, boiling is continued for 1--1\ba1/2\be hours and the goods are rinsed and dried to obtain fast orange dyeings; the 1 : 3-dioxybenzene-4-carboxylic acid may be replaced by 8-sulpho-2 : 3-oxynaphthoic acid and the chromium compound may be replaced by that of the dyestuffs 1 : 2 : 4-aminonaphtholsulphonic acid --> 1-(3<1>-sulphamido)phenyl-3-methyl-5-pyrazolone or 2 : 1 : 4 : 8-aminonaphtholdisulphonic acid --> 2-naphthol; (5) Wool is entered into a bath at 60--70 DEG  C. containing sulphuric acid, benzenesulphonic acid and the chromium compound of the dyestuff from nitrated 1-diazo-2-naphthol-4-sulphonic acid and 1-naphthol-8-sulphamide, the temperature is raised to the boil in \ba1/2\be hour, a further quantity of sulphuric acid is added, boiling is continued for 1\ba1/2\be hours and the goods are rinsed and dried to obtain full, very fast, black dyeings; alternatively the whole of the sulphuric acid may be present originally. Specification 364,148 is referred to.