GB405144A - Manufacture of azo-dyestuffs - Google Patents

Abstract

Azo dyes; azo dyes, forming on the material; lakes.--Azo dyes, insoluble in water, are produced in substance, on a substratum or on the fibre by coupling with an arylide of 2 : 3-oxynaphthoic acid a diazotized aminobenzotrifluoride containing a second trifluoromethyl group with or without any other substituent, only such components being used as are devoid of groups inducing solubility in water. Orange shades are obtained of a yellower hue than those obtained with the dyestuffs of the parent Specification. The dyeings are of good fastness to light, to boiling water and to washing. The following examples are specified. (1) to (6) Cotton yarn is grounded with a liquor containing turkey red oil, caustic soda and formaldehyde and (1) the anilide, (2) the 3-nitranilide, (3) the 2-anisidide, (4) the 1-naphthylamide, (5) the 4-chloro-2-methylanilide, (6) the 4-chloranilide of 2 : 3-oxynaphthoic acid and developed with diazotized 1 - amino - 3 : 5 - bis - trifluoromethylbenzene. (7) The dyestuff 1-amino-3 : 5-bis-trifluoromethylbenzene --> the anilide of 2 : 3-oxynaphthoic acid is prepared in substance. A table is also given showing the shades obtained with the following dyestuffs: 1-amino-2 : 5-bis-trifluoromethylbenzene --> the 2-phenetidide, 2-anisidide, 4-anisidide, anilide and 4-chloranilide of 2 : 3-oxynaphthoic acid and 1-amino-3 : 5-bis-trifluoromethylbenzene --> the 2-toluidide of 2 : 3-oxynaphthoic acid. Specifications 6379/12, [Class 2 (iii), Dyes &c.], and 17279/13, [Class 15 (ii), Dyeing, Processes &c. for], also are referred to. 1 - Amino - 3 : 5 - bis - trifluoromethylbenzene and the corresponding 2 : 5 - bis compound are obtained by reduction of the products of nitration of 1 : 3 - and 1 : 4 - bis - trifluoromethylbenzene, respectively as described in French Specification 745,293.