Patent GB-590426-A (GB)
Title: Manufacture of new stilbene dyestuffs
IPC: C09B56/04
Filed: 1945-04-11
Abstract: Stilbene dyestuffs are manufactured by condensing, in the presence of caustic alkalies, one molecular proportion of 4 : 41-dinitro-stilbene- or - dibenzyl-2 : 21-disulphonic acid or the conversion products obtained by the action of caustic alkalies (with or without the application of pressure) on 4-nitrotoluene-2-sulphonic acid, and 0.5-1.5 molecular proportions of one or more aminotriazoles (P) of the formula <FORM:0590426/IV/1> containing in the naphthalene nucleus at least one water-solubilizing group, e.g. a carboxylic or sulphonic acid radical, but no amino or substituted amino groups, together with one or more aminoazo compounds (Q) of the formula <FORM:0590426/IV/2> (wherein Y stands for a sulphonic acid or carboxyl group and wherein the amino group may carry substituents capable of being split off by alkalies and the benzene nuclei may contain further substituents not interfering with the formation of the aminoazo compound), or with the copper complex of such an aminoazo compound, the sum of the molecular proportions of P and Q not exceeding 2, and, in so far as metallizable groups are still present, treating the product with copper-yielding agents (e.g. water-soluble copper salts), and, if desired, treating the coppered dyestuff with a mild oxidizing agent.  The condensation may be carried out at the boil under atmospheric or superatmospheric pressure.  The aminotriazoles (P) are obtainable by diazotizing 4-nitro-41-aminostilbene-2 : 21-disulphonic acid, coupling with such naphthylamine derivatives as are capable of coupling in o-position to the amino group and contain at least one water-solubilizing group, treating the products with oxidizing agents, e.g. sodium hypochlorite, copper salts or chlorine, and reducing the nitro group. The aminoazo compounds (Q) are obtainable by coupling the appropriate o-substituted diazonium compounds with the appropriate m-substituted anilines, or with N-methane-o -sulphonates thereof, with or without subsequent hydrolysis.  The products of the invention dye cellulosic materials, e.g. cotton, including the cotton in a wool-cotton mixture, in brown and olive shades.  In examples: (1) 1 mol. of the disodium salt of 4 : 41-dinitrostilbene-2 : 21-disulphonic acid is refluxed in aqueous caustic soda solution with 1 mol. of the trisodium salt of the aminotriazole from 2-naphthylamine-6-sulphonic acid and 1 mol. of the sodium salt of the aminoazo compound 2-aminophenol-4-sulphonic acid --> m-anisidine, and the product is heated with ammoniacal copper sulphate solution; (2) the aminoazo compound in (1) is replaced by 2-aminophenol-4-sulphonic acid --> 2 : 5-dimethoxyaniline; (3) the aminotriazole in (2) is replaced by that from 1-naphthylamine-4-sulphonic acid; (4) the aminoazo compound in (1) is replaced by 4-chloro-2-aminophenol-6-sulphonic acid --> m-anisidine, and (5) by 6-chloro-2-aminophenol-4-sulphonic acid --> m-anisidine; (6) the aminotriazole in (4) or (5) is replaced by that from 2-naphthylamine-7-sulphonic acid; (7) the aminotriazole in (1) is replaced by that from 1-naphthylamine-4-sulphonic acid, and the product is heated with sodium hypochlorite solution; (8) 0.3 mol. of the aminoazo compound in (1) is replaced by 0.3 mol. of the sodium salt of 2-aminophenol-4-sulphonic acid --> 2 : 5-dimethoxyaniline; the product may be treated with sodium hypochlorite as in (7); (9) the aminoazo compound in (1) is replaced by its copper complex compound, and the coppering step is omitted; (10) the aminotriazole in (1) is replaced by that from 2-amino-3-naphthoic acid; (11) the amount of the aminotriazole in (1) is increased to 1.5 mols. and that of the aminoazo compound reduced to 0.5 mol.; the product may be treated with an aqueous solution of sodium hypochlorite and caustic soda; (12) the amount of the aminotriazole in (2) is reduced to 0.5 mol. and that of the aminoazo compound increased to 1.5 mol.; (13) the aminoazo compound in (1) is replaced by 0.5 mol. each of the sodium salts of 6-chloro-2-aminophenol-4-sulphonic acid --> m-anisidine and 2 : 5-dimethoxyaniline respectively, or the corresponding compounds from 4-chloro-2-aminophenol-6-sulphonic acid; (14) the aminoazo compound in (2) is replaced by 4-chloro-2-aminophenol-6-sulphonic acid --> 2 : 5-dimethoxyaniline. Other starting materials specified are: for the preparation of the aminotriazoles: 2-naphthylamine - 5 - monosulphonic and -3 : 6-, -5 : 7- and -6 : 8-disulphonic acids; for the preparation of the aminoazo compounds: diazo components: 2-aminophenol-4 : 6-disulphonic acid, 3 - amino - 2 - hydroxy - 5 - sulphobenzoic acid and 4-chloro-2-aminophenol-5-sulphonic acid; coupling components: m-anisidine-N-methanesulphonate, m-phenetidine and 1 - amino - 2 - methyl - 5 - methoxybenzene.  Specifications 311,384, [Class 2 (iii)], 348,283 and 427,241 are referred to.