Patent GB-632932-A (GB)
Title: Production of colored designs on textile material by the diazotype process
IPC: D06P1/12
Filed: 1946-07-30
Abstract: 632,932. Textile materials sensitized to light by diazo compounds. GENERAL ANILINE & FILM CORPORATION. July 30, 1946, No. 22698. Convention date, Aug. 18, 1945. [Class 98 (ii)] Textile material is impregnated with a lightsensitive diazo compound decomposable by light to form a non-coupling compound, an azocoupling, coupling in alkaline medium, and zinc chloride, the zinc chloride being in amounts of from 4 to 10 per cent by weight of the sensitizing solution exclusive of any required to form a complex salt with the diazo compound. The textile material may be cotton, regenerated cellulose, cellulose acetate, wool, silk, nylon, or polyvinyl chloride, or the material may be leather, and is preferably not sized. The material may be developed with ammonia gas. An exposed bolt of cloth may be placed in an autoclave which is exhausted and then filled with moist ammonia gas under pressure. The autoclave may be heated during or after the introduction of the ammonia. The diazo compound preferably has a low coupling energy, and the coupler is preferably rapid coupling and used in excess. The coupler may be a polyhydroxy compound of the benzene or naphthalene series, an acetoacetic arylide, or a pyrazolone or pyrazolone carboxylic acid, and in particular may be 7-hydroxy-1: 2-naphthimidazole, 2: 3-dihydroxynaphthalene, ethylene di-(2: 3-hydroxynaphthoyl) amide, resorcinol, 1 -p - tolyl - 3 - methyl - 5 - pyrazolone, acetoacetanilide, acetoacetylbenzylamide, or a mixture of 2: 3-dihydroxynaphthalene and m-hydroxyphenylurea. The diazo compound may be diazotized p-diethylamino-m-toluidine, p-ethylamino-o-toluidine, p-diethylamino-m-ethoxyaniline, p-diethylamino-o-toluidine, p-diethylaminoaniline, o-carboxy-p-diethylaminoaniline, or p - (N - hydroxyethyl: N - n - butyl) - amino - aniline, and may be used as the zinc chloride, boron trifluoride, or cadmium chloride double salt. A precoupling stabilizer, such as citric acid, a mixture of citric, boric, and phosphoric acids, tartaric acid, a a : #-unsaturated aliphatic acid, or a naphthalene polysulphonic acid, may be incorporated in the sensitizing solution. The cloth may first be dyed to a colour different from that produced by the diazo compound and coupler, and may be mordanted with alum or aluminium sulphate. In an example, cellulose acetate is sensitized with an aqueous solution of the zinc chloride double salt of diazotized p-diethylamino-o-toluidine, 2: 3-dihydroxynaphthalene, citric acid, zinc chloride, and saponine, and after exposure is developed in ammonia gas. The 2: 3-dihydroxynaphthalene may be replaced by 7-hydroxy-l: 2- naphthimidazole, resorcinol, or ethylene di- (2: 3-dihydroxynaphthoyl) amide, or the diazonium compound by p-phenylaminobenzene diazonium sulphate, the zinc chloride double salt of p-diethylamino-o-carboxybenzenediazonium chloride, the zinc chloride double salt of diazotized p-diethylamino-o-phenetidine, the zinc chloride double salt of p-diethylaminobenzene diazonium chloride (with 7-hydroxy- 1: 2-naphthimidazole as coupler), or the zinc chloride double salt of diazotized p-ethylaminom-toluene diazonium chloride. In another example, cellulose acetate is sensitized with a composition comprising p-phenylaminobenzene diazonium sulphate, m-hydroxyphenylurea, 2: 3-dihydroxynaphthalene, citric acid, zinc chloride, saponine, isopropyl alcohol, and water. The Specification as open to inspection under Sect. 91 contains also an example in which regenerated cellulose is sensitized with a composition comprising the zinc chloride double salt of diazotized p-(N-hydroxyethyl: N-nbutyl) - aminoaniline, 2: 3 - dihydroxynaphthalene, citric acid, thiourea, isopropyl alcohol, saponine, and water, is exposed under a redcomponent positive, and developed in ammonia gas to give a blue image, is re-sensitized with a composition containing the zinc chloride double salt of diazotized p-diethylamino-o-toluidine, 1-p-tolyl-3-methyl-5-pyrazolone, citric acid, thiourea, isopropyl alcohol, saponine, and water, is exposed under a green-component positive, and-developed in ammonia gas to give a red image, and is re-sensitized with a composition comprising the zinc chloride double salt of diazotized p-diethylamino-o-toluidine, acetoacetyl-o-anisidine, and the other ingredients, is exposed under a blue-component positive, and is developed in ammonia gas to give a yellow image, and refers to the addition of metal salts to the sensitizing composition. This subject-matter does not appear in the Specification as accepted.