GB778718A - Cobaltiferous monoazo-dyestuffs and process for making them - Google Patents

Abstract

The invention comprises cobalt complexes of dyestuffs of formula <FORM:0778718/IV(b)/1> where R is a benzenic residue containing a hydroxyl group ortho to the azo linkage, Y1 is a substituted sulphonamide group and R1OH is a residue of a 2-naphthol bound in the 1-position to the azo link and which contain substantially one atom of cobalt per two molecules of dyestuff and no sulphonic or carboxylic acid groups. The metallized dyestuffs are made by treating the metal-free dyestuffs with cobalt yielding agents under conventional conditions preferably using less than one atomic proportion of cobalt per molecular proportion of dyestuff and/or to carry out the metallization in a weakly acid to alkaline medium. The sulphonamide group may be of formula <FORM:0778718/IV(b)/2> where X1 is H or an aliphatic residue and X is an aliphatic, alicyclic, araliphatic or aromatic residue or together with X1 and N is a heterocyclic residue. Advantageously the sulphonamide group is of formula <FORM:0778718/IV(b)/3> n is an integer not greater than 7 and X is an alkyl or aryl residue. The benzene residue of the diazo component may contain substituents such as sulphonamide groups, or substituents which do not impart solubility in water e.g. Cl, Me, O Me, No2 and CO Me. Diazo components may be obtained from the following specified amines:- 4 - methyl-, - methoxy-, - chloro-and - nitro-, 5 - nitro-, 6 - acetylamino - 4 - chloro - or - nitro -, 5 - or 6 - nitro - 4 - chloro -, 6 - nitro - 4 - methyl - or - acetylamino -, 4,6 - dinitro - or dichloro - and 4-nitro - 6 - chloro - 2 - aminophenol, 3 - amino - and 5 - nitro - 3 -amino - 4 - oxy - acetophenone, 2 - aminophenol - 4 - carboxylic acid amide, 6 - nitro - or - chloro - 2 - aminophenol - 4 - sulphonic acid amide or - N - methylamide, 2 - aminophenol - 4 - or, - 5 - sulphonic acid - N - methyl-, - ethyl - , -isopropyl -, - butyl-, - b - oxyethyl, - N1 N - dimethyl-, - diethyl -, -dioxyethyl-, - N - cyclohexyl -, - phenyl -, - N - methyl - N - phenyl -, - N - p - tolyl-, - p - chlorophenyl - amides 2 - amino - phenol - 4 - sulphonic acid pyrrolidiae, 4-chloro - 2 - amino - phenol - 6 - sulphonamide, 2 - aminophenol - 4 - or - 5 - sulphonamide and 4 - chloro - or - methoxy - 2 - aminophenol - 5 - sulphonamide. Coupling components specified are 2 - naphthol- 3 -, - 4 -, - 5 -, - 6 -, and - 7 - sulphonic acid - N - methyl -, - ethyl -, - butyl -, - phenyl -, - 41 - chlorophenyl -, -N,N - dimethyl - and - diethyl - and - N - methyl - N - phenyl - amide. The metal free dyestuffs are preferably made by alkaline coupling and used as their filter cakes in the metallization process. The metal dyestuffs dye silk, leather, wool and superpolyamide or polymethane fibres from weakly acid baths. Examples illustrate the preparation of dyestuffs using certain of the above specified components and their use in dyeing wool which is dyed in violet tints. Specification 731,114 is referred to.