Patent GB-728259-A (GB)
Title: Process for the preparation of metallisable o-hydroxymonoazo dyestuffs and of their metal complex compounds
IPC: C09B45/16
Filed: 1953-02-03
Abstract: The invention comprises: metallizable o-hydroxymonoazo dyestuffs of the general formula <FORM:0728259/IV (c)/1> (wherein R represents a radical of the bezene or naphthalene series containing one hydroxy group in ortho-position to the azo linkage and also containing a sulphonic acid group and, if desired, other substituents, and R1CO represents a formyl group, an acetyl, propionyl, butyryl or valeryl group or halogen, alkoxy, aryloxy or or carboxy derivative thereof, or a fumaryl group), and their metal complex compounds; the preparation thereof by (a) coupling the appropriate components in a concentrated caustic alkaline medium, or (b) treating the corresponding dyestuffs having a free amino group in the 1-position with an aliphatic carboxylic acid or a functional derivative thereof, and in either case, if desired, treating the product with a metal-yielding substance; and a process of dyeing or printing with the metalliferous dyestuffs, or with the metal-free dyestuffs with metallization on the material.  The starting materials for process (b) above are obtainable by coupling a diazotized o-amino-phenol- or -naphthol-sulphonic acid with 1-amino - 8 - naphthol in a strongly alkaline medium, or with 1 : 8 - diaminonaphthalene followed by partial hydrolysis by boiling in dilute acid medium.  The metal-free dyestuffs dye animal fibres (especially wool and silk but including also artificial nitrogenous fibres such as those from casein or from polyamides) by the metachrome and after-chrome processes in blue, green to grey shades.  More reddish shades are obtained by treating the dyestuffs on the fibre with a compound yielding cobalt instead of chromium.  Examples describe the preparation of the following dyestuffs: (1) 1-amino-2-naphthol-4-sulphonic acid --> 1-acetylamino-8-naphthol (which dyes animal fibres from an acid bath in cobalt-blue shades becoming greenish-grey when after-chromed); (2) 4-chloro - 2 - aminophenol - 6 - sulphonic acid --> 1-acetylamino-8-naphthol (which is applied to wool from a bath containing ammonium sulphate and cobalt acetate, yielding a violet dyeing); (3) 4-nitro-2-aminophenol-6-sulphonic acid --> 1-acetylamino-8-naphthol (which dyes animal fibres grey-green by the metachrome or after-chrome process); (4) 4-chloro-2-aminophenol-6-sulphonic acid --> 1-propionylamino-8-naphthol (which dyes animal fibres blue by the after-chrome or metachrome process); (5) the same diazo component --> 1-formylamino-8-naphthol.  In further examples: (6) the dyestuff of (2) is boiled with an aqueous solution of chromosalicylic ammonia, or (7) with an acidified aqueous solution of chromium formate, or (8) with a solution obtained by heating chromium formate with formamide in aqueous solution; the product in each case dyes animal fibres blue from a weak acid bath; (9) the dyestuff of (2) is boiled with an aqueous solution of cobaltous tartrate; the product dyes animal fibres violet from a weak acid bath; (10) wool is treated at 60 DEG C. in a bath containing ammonium chromate and ammonium sulphate, after which the dyestuff of (2) is added and the bath raised to the boil, yielding a blue dyeing.  Additional components specified are: 1-amino-2-hydroxy-6-nitronaphthalene-4-sulphonic acid, 1 - amino - 2 - naphthol - 4 : 6 - disulphonic acid, 4 - alkyl - 2 - aminophenol - 6 - sulphonic acids, 4-chloro-5-nitro-2-aminophenol-6-sulphonic acid, 4-benzoylamino- and 4-bromo-2-aminophenol-6-sulphonic acid, and 3 : 4 : 6-trichloro-2-aminophenol-5-sulphonic acid; N - n - butyryl-, N - n - valeryl-, N-b -chloropropionyl-, N-ethoxyacetyl-, N - phenoxyacetyl, N - b  - methoxypropionyl-, N - b  - carboxypropionyl- and N - fumaryl - 1 : 8 - aminononaphthol.  Specification 591,454, [Group IV], is referred to.