Patent GB-626916-A (GB)
Title: Manufacture of disazo-dyestuffs
IPC: C09B31/057
Filed: 1947-01-23
Abstract: Aminoarylsulphonamides of the general formula <FORM:0626916/IV (b)/1> (wherein R1 represents a methyl or ethyl radical and R2 a benzene radical in which the groups -O2S- and -N = N- are in m- or p-position to one another) are manufactured by condensing 1-nitrobenzene-3-sulphochloride, 1-methyl-, 1 - methoxy- or 1 - chloro - 2 - nitrobenzene - 4 - sulphochloride 1 - methyl- or 1-chloro-4-nitrobenzene-6-sulphochloride, or 1-nitrobenzene-4-sulphochloride, with an appropriate secondary amine, e.g. N-methyl- or N-ethyl-aniline, or N-ethylmetanilic acid, sulphonating the product if necessary, and reducing the nitro group to an amino group.  The Specification as open to inspection under Sect. 91 comprises also the manufacture of other aminoarylsulphoramides of the general formula <FORM:0626916/IV (b)/2> (wherein R1 represents hydrogen or an alkyl or cycloalkyl radical, R2 hydrogen or an alkyl, aralkyl, aryl or cycloalkyl radical and R3 a benzene radical) by a similar process using ammonia or a primary or secondary amine, e.g. mono- or di-methylamine, mono- or di-ethanolamine, dipropylamine, butylamine, cyclohexylamine, aniline, p-toluidine, o-anisidine or N-hydroxyethylaniline.  This subject-matter does not appear in the Specification as accepted.ALSO:Diazo dyestuffs, which dye animal fibres in violet-blue to navy blue tints, are manufactured by coupling a diazo compound of a monoazo dyestuff of the general formula <FORM:0626916/IV (c)/1> wherein R1 represents an alkyl hydrocarbon radical (especially methyl or ethyl) and R2 represents a benzene radical in which the groups -O2S- and -N=N- are in m- or p-position to one another (especially a 1 : 3-phenylene radical in which one of the 4- and 6- positions is unsubstituted and the other unsubstituted or substituted by halogen or methyl), with a 1-aryl-aminonaphthalene-8-sulphonic acid (especially 1-N-phenylamino- or 1-N-p-tolylamino-naphthalene-8-sulphonic acid).  The monoazo dyestuffs used as starting materials may be prepared by coupling a -naphthylamine with a diazotized aminoarylsulphonamide of the general formula <FORM:0626916/IV (c)/2> e.g. 3 - aminobenzenesulphonic a acid - (1) - (N - methylanilide-X-sulphonic acid) and its 4- and 6-chloro- and 4- and 6-methylderivatives, 3-aminobenzenesulphonic acid - (1) - (N - ethylanilide-31-sulphonic acid) or 4-aminobenzenesulphonic acid - (1) - (N- methylanilide - X - sulphonic acid, (the compounds in which the position of the sulphonic acid group is indeterminate being made by condensing the appropriate nitrobenzenesulphochloride with N-methylaniline, sulphonating, and reducing the nitro group to an amino group). Examples describe the preparation of dyestuffs from the components specified above, and the dyeing of wool with one of the products.  The Specification as open to inspection under Sect. 91 comprises also the manufacture of diazo dyestuffs (containing two sulphonic acid groups) from, on the one hand, other monoazo dyestuffs of the general formula <FORM:0626916/IV (c)/3> wherein R1 represents hydrogen or an alkyl or cycloalkyl radical (e.g. methyl, ethyl, propyl or hydroxyethyl), R2 hydrogen or an alkyl, aralkyl, aryl or cycloalkyl radical (e.g. methyl, propyl, butyl, hydroxyethyl, phenyl, p-tolyl, o-anisyl or cyclohexyl), R3 a benzene radical and R4 a 1 : 4-naphthylene radical (e.g. the residue of 1-naphthylamine-6- or 7-sulphonic acid), and, on the other hand, 1-alkylaminonaphthalene-8-sulphonic acids (e.g. 1-ethylaminonaphthalene-8-sulphonic acid).  This subject-matter does not appear in the Specification as accepted.