GB784622A - Tetrakisazo dyestuffs and process of making the same - Google Patents

Abstract

The invention comprises dyestuffs of formula <FORM:0784622/IV (b)/1> where R is H or an alkyl, hydroxyalkyl or aryl radicle, R1 and R2 are benzene or naphthalene residues and R3 is a benzene residue in which NHCONHR is o and NH p to -N=N-. They are made by coupling diazotized amino monoazo dyestuffs of the benzene or naphthalene series with an appropriate 3-amino-1-phenyl urea and converting the diazo dyestuffs thus obtained into their ureas, e.g. by treatment with phosgene. The dyestuffs dye cotton and regenerated cellulose in red shades. In examples which illustrate the preparation of the dyestuffs and their use in dyeing processes, the disazo dyes used are 4-aminoazobenzene-3,41-disulphonic acid, aniline-2,4- and 2,5-disulphonic acids --> 2,5 - dimethylaniline, 2 - naphthyl - amine-6,8-disulphonic acid --> 3 - methyl - aniline and aniline - 3 - sulphonic acid --> 1 - naphthylamine - 7 - sulphonic acid and the phenylureas are 3-aminophenyl, N-(3-amino)-1-phenyl - N1 - hydroxyethyl, 3 - sulphophenyl and methyl and 3-amino-4-methyl-1-phenyl ureas the final ureas being obtained by treatment with phosgene.