GB371163A - A process for dyeing or colouring celluloid or shaped articles thereof - Google Patents

Abstract

Unspecified types of dyes, dyeing with; azo dyes.--Celluloid (i.e. nitrocellulose plastics) and shaped articles thereof are dyed or coloured by treatment with a fine aqueous dispersion of a dyestuff which is insoluble or sparingly soluble in water such as is used for dyeing cellulose acetate. Specified dyestuffs are (a) nitramines such as nitranilines, nitronaphthylamines, and nitrodiphenylamines, e.g. 2 : 4-dinitro-4<1>-oxydiphenylamine; (b) azo dyes such as 3 - methyl - 6 - oxy - 4<1> - acetylaminoazobenzene, 3-methyl-6 - oxy - 4<1> - methoxyazobenzene, aminoazobenzene, aminoazotoluene, 2 : 5-dichloro-4<1>-aminoazobenzene, 4-nitro-4<1>-aminoazobenzene, 4-nitro-2<1>-methyl-5<1> - methoxy - 4<1>-aminoazobenzene, 4-nitro-2<1> : 5<1>-dimethoxy-4<1>-aminoazobenzene, 2-methoxy-4-nitro-4<1>-diethylaminoazobenzene, and the products obtained by coupling diazobenzene with 1-phenyl-3-methyl-5-pyrazolone, 1-(2<1>-chloro) phenyl-3-methyl-5-pyrazolone, 2 : 4-dioxyquinoline or methylketol or by coupling diazotized 2-nitro-4-chloraniline or 3-nitro-4-aminotoluene with 3-methyl-5-pyrazolone; (c) indophenols such as those obtainable by simultaneous oxidation of 2 : 6-dichloro-4-aminophenol and diethylaniline or dimethylaniline; (d) aminoanthraquinones such as the 1-methyl-2-amino-, 1-amino-4-oxy-, 1 - amino - 4 - methoxy-, 1 : 4-diamino-, 1 : 4 : 5 : 8-tetramino-, 1 : 4-di (oxyethylamino)-5 : 8-dioxy-, 1 - amino - 4 - phenylamino- and 1 - methylamine - 4 - phenylamino-derivatives of anthraquinone. In an example celluloid articles such as buttons, buckles &c. to be coloured are subjected to a preliminary purification by treatment in a bath of dilute ammonia solution at about 40 DEG C. and are then coloured by introduction into a bath at 45 DEG C. containing an aqueous solution of Marseilles soap in which the dyestuff aniline --> 1-(2<1>-chloro) phenyl-3-methyl-5-pyrazolone is emulsified, raising the temperature to 60-70 DEG C., maintaining at this temperature for \ba1/2\be hour, rinsing and drying, e.g. by rubbing with dry soft sawdust.