Patent GB-436371-A (GB)
Title: Process for the manufacture of water-insoluble azodyestuffs on the fibre
Filed: 1934-04-03
Abstract: Water-insoluble azo dyes are made on the fibre by applying diazoamino compounds and coupling components, and developing the dyestuff at a neutral to weakly alkaline reaction under the influence of an elevated temperature and in the presence of moisture the coupling components, if applied in the form of their salts, being transformed, by treatment with an alkali-binding agent, at least partially into the free hydroxy form prior to the coupling.  An alkaline reacting printing paste containing the diazoamino compound and the coupling component may be applied and the print treated with an acid reacting substance to produce the neutral or weakly alkaline reaction but preferably there are used as alkali-binding agents salts which under the conditions of working do not split off free acid such as salts of weak bases with strong acids and taurine.  The process may be applied simultaneously with the development of vat or aniline black dyestuffs.  Suitable diazoamino compounds are those described in Specifications 320,324, 324,041, 329,353, 334,529, [all in Class 2 (iii)], 407,840, 427,803, and 433,878.  In examples: (1) cotton is impregnated with 2 : 3-oxynaphthoic acid anilide in dioxane and pyridine solution, padded with a solution of the diazoamino compound from diazotized 4-chloro-2-toluidine and 4-sulpho-2-aminobenzoic acid and the colour developed by steaming; (2) cotton is printed with a paste containing the diazoamino compound from diazotised 4-chloro-2-toluidine and methylaminoethanesulphonic acid and the sodium salt of the o-anisidide of 2 : 3-oxynaphthoic acid, padded on the reverse side with aqueous ammonium sulphate with or without sodium chloride and steamed; (3) cotton is printed with a paste containing the diazoamino compound from diazotized 6-amino-3-benzoylamino-1 : 4-diethoxybenzene and methylaminoacetic acid, sprayed on the reverse side with aqueous ammonium chloride or diethylamine hydrobromide and developed as above; (4) cotton is printed with a paste containing the diazoamino compound in (1) and the o-phenetidide of 2 : 3-oxynaphthoic acid, padded with an ammoniacal solution of ammonium naphthalene-1 : 5-disulphonate or sulphoacetate, and the colour developed in a steaming box; (5) cotton is printed with a paste containing the diazoamine compound from diazotized 4-chloro-2-toluidine and d, l-a -pyrrolidine carboxylic acid (or a piperidine sulphonic acid) and 6 - ethoxy - 2 - acetoacetylaminobenzothiazole, impregnated with an aqueous solution of the methylamine salt of methane- (or ethane-) disulphonic acid and passed over a heated drying drum (cf. Specification 393,408); (6) cotton is printed with a paste containing the sodium salt of the o-toluidide of 2 : 3-oxynaphthoic acid and the diazoamino compound from diazotized 5-nitro-2-toluidine and disodium cyanamide, padded on the reverse side with a liquor containing ammonium sulphate, ammonium chloride, ammonia, and starch tragacanth and the prints are steamed; (7) similar to (2) using a paste containing the anilide of 2 : 3-oxy naphthoic acid and the diazoamino compound from diazotized 4-chloro-2-aminodiphenylene ether and 2-methylamino-5-sulphobenzoic acid, a padding liquor containing the ammonium salt of p-toluenesulphonic acid or p-toluene sulphinic acid, and developing with steam containing ammonia; (8) cotton is printed with pastes containing (a) the diazoamino compound from diazotized 4 : 5-dichloro-2-toluidine and 4 - sulpho - 2 - aminobenzoic acid and the sodium salt of the m-nitranilide of 2 : 3-oxynaphthoic acid, (b) the vat dyestuff of p  Specification 181,304, [Class 2 (iii)], and the colours developed as in (2); (9) similar to (2) using a paste containing the p-chloroanilide of 2 : 3-hydroxycarbazole carboxylic acid and the diazoamino compound from diazotized 4-chloro-2-anisidine and methylglucamine (or dipropanediolamine), impregnating with an aqueous ammoniacal solution of ammonium phosphate and steaming; the printing paste may be mixed with that described in example (3); (10) cotton is printed with a paste containing the diazoamino compound from diazotized 2 : 5-dichloroaniline and 4-sulpho-2-aminobenzoic acid and diacetoacetyl-o-tolidine, padded with an aniline-black liquor containing ammonium nitrate, steamed, chromed and finished.