Patent GB-612174-A (GB)
Title: Manufacture of polyazo dyestuffs
IPC: C09B35/40
Filed: 1946-05-15
Abstract: Polyazo dyestuffs are manufactured by coupling a tetrazotized diamino compound of the general formula <FORM:0612174/IV (c)/1> (wherein X represents a direct linkage, -NHCO-, -CONH- or -NHCONH- and the nuclei A and B may have further substituents) in any desired order with equimolecular proportions of, on the one hand, a monoazo dyestuff of the general formula <FORM:0612174/IV (c)/2> (wherein Y represents a hydroxy group or a group convertible thereto under conditions of metallization and the nucleus C may have further substituents) and, on the other hand, a 3-methyl-5-pyrazolone of the general formula <FORM:0612174/IV (c)/3> (wherein R represents hydrogen, an alkyl group or an aryl radical which may be substituted as desired), the components being so chosen that the products contain at least one sulphonic acid group; or by coupling a diazotized nitro or acylamino compound of the general formula <FORM:0612174/IV (c)/4> (wherein Z represents a nitro or acylamino group) with an equimolecular proportion of one of the components (II) or (III), converting the nitro or acylamino group to an amino group, diazotizing and coupling with an equimolecular proportion of the other component (III) or (II).  The products dye natural or regenerated cellulose in yellowish to reddish-brown shades, and may be treated on the fibre with copper-yielding agents.  Suitable components, the use of which is illustrated in examples and a table, are: diamino, nitro or acylamino compounds (I) or (IV): benzidine, monoacetylbenzidine, o-tolidine, dianisidine, benzidine-3-sulphonic acid, 41-monoacetylbenzidine-3-sulphonic acid, m- and p-amino- and -nitro-benzoyl-m- and p-phenylenediamine and their sulphonic and carboxylic acids, and 3 : 31- and 4 : 41-diaminodiphenylurea and their alkyl and alkoxy substitution products; diazo components for the preparation of components (II): 2-amino-1-hydroxy- or -alkoxybenzenes, such as 2-amino-1-hydroxy- and -methoxy-benzene and their 4-sulphonic and 4-carboxylic acids and 4-sulphonamides, 4-chloro- and 4-, 5- and 6-methyl-2-amino-1-hydroxy-, -methoxy- and -ethoxy-benzene, 4-or 6-chloro-, -nitro-, -acetylamino- and -benzoylamino-2-aminophenol-6- or 4-sulphonic acids, 4- or 6-chloro-2-amino-1-methoxybenzene-6- or 4-sulphonic acids, 4 : 41-dihydroxy-3-aminobenzenesulphonanilide-31 -carboxylic acid, 4 : 41- di-hydroxy - 3 - aminobenzophenone - 31 - carboxylic acid, 4-methyl-2-aminophenoxyacetic acid and 4-nitro-2-aminophenol; pyrazolone components (III): 3-methyl-, 1 : 3-dimethyl- and 1-ethyl-3-methyl - 5 - pyrazolone, 1 - phenyl - 3 - methyl - 5-pyrazolone and its methyl, chloro, amino, sulphonic acid and sulphonamide substitution products, and 1-dehydrothiotoluidinesulpho-3-methyl-5-pyrazolone. Specifications 101,601, [Class 2 (iii)], 446, 595 and 572,852 are referred to.  The Specification as open to inspection under Sect. 91 comprises also: (a) the coppering of the dyestuffs in substance; (b) the use of the preformed copper compounds of the monoazo dyestuffs (II); (c) the use, instead of the monoazo dyestuffs (II), of the disazo dyestuffs 1 - amino - 4 - hydroxybenzene - 3 - carboxylic acid --> 1 - amino - 2 - methoxy - 5 - methylbenzene --> resorcinol and 4-chloro-1-aminobenzene-3-sulphonic acid --> 4-methyl-2-aminophenol --> resorcinol; and (d) an example of an alternative process in which tetrazodiphenyl-sulphonic acid is coupled with 3-methyl-5-pyrozolone and resorcinol and the resulting disazo dyestuff is coupled with a diazotized 2-aminophenol compound.  This subject-matter does not appear in the Specification as accepted.