GB472823A - Manufacture of arylides of 2:3-hydroxynaphthoic acid and of azo-dyestuffs therefrom - Google Patents

Abstract

Arylides of 2 : 3-hydroxynaphthoic acid are made by condensing 2 : 3-hydroxynaphthoic acid with a 2-amino-3-alkoxydiphenyleneoxide, which may be substituted in at least one of the 5-, 6-, 7- and 8-positions of the diphenyleneoxide nucleus, e.g. by halogen, alkyl or alkoxy groups. In examples, (1) and (2) the acid is condensed with 2-amino-3-methoxy- or ethoxydiphenyleneoxide in presence of chlorbenzene and phosphorus trichloride; 6- or 7-methyland 7 - chloro - 2 - amino - 3 - methoxydiphenyleneoxides and 2 - amino - 3 : 7 - dimethoxydiphenyleneoxide are also specified. They have a high affinity for cotton in alkaline solution. Specification 472,170 is referred to. Azo dyes insoluble in water are made in substance, on the fibre or on a substratum adapted for the production of lakes by coupling a diazo compound with one of the above-mentioned arylides the components being free from solubilizing groups, such as SO3H or COOH. In examples (3) cotton is impregnated with a solution of 2-(2<1> : 3<1>-hydroxynaphthoylamino)-3-methoxydiphenyleneoxide, alcohol, caustic soda, formaldehyde, glue and turkey red oil and developed with diazotized 2-amino-4 : 4<1>-dichlorodiphenyl ether (very clear yellowish red), (4) the dyestuff of (3) is produced in substance. In a table the following additional diazo components are specified: 5-bromo-4-chloro - 2 - amino - 1 - toluene, 4 : 6 - dichloro - 2 - toluidine 4 - or 5 - chlor - 2 - toluidine, 3 - nitro - 4 - toluidine, 4 - or 5 - nitro - 2 - toluidine, 2 : 5-dichloraniline, o-nitroaniline, 4-nitro-2-methoxyaniline, 2 : 4-dimethylaniline, 4 - chlor - 2 - aminoanisole, 5 - methyl - 2 - amino - 1 - nitrobenzene, 5 - chlor - 2 - amino - 1 - nitrobenzene, m - chloraniline, 5 - trifluoromethyl - 1 - aminophenyl - 2 - ethylsulphone. British Specification 374,548 and U.S.A. Specification 1,936,926 also are referred to.