GB902228A - Polyazo-dyestuffs derived from barbituric acid and process for their manufacture - Google Patents

Abstract

The invention comprises dyes of formula <FORM:0902228/IV (b)/1> where R is the residue of a diazo component containing at least one azo group, and also contains a metallisable group in a vicinal position to the N=N-A group, and A is the residue of a naphthol sulphonic acid bound to R-N=N- vicinal to the hydroxy group the naphthalene nucleus of A being advantageously bound directly to the two azo links, and the heavy metal, especially copper, complexes of the dyes. The dyes are made by coupling barbituric acid with appropriate diazo components, or metal complexes thereof, the metal-free dyes being subsequently metallised if required. The dyes may also be made by coupling a diazo compound of an amine RNH2 with the necessary naphthol-azo-barbituric acid component with metallisation of the product if necessary. Preferred are dyes of formula <FORM:0902228/IV (b)/2> where m and n are 1 or 2, R1 and R3 are benzene or naphthalene residues and R2 is a benzene, naphthalene, diphenyl or 5-pyrazolone residue and especially dyes where m is 1, or is 2 and R2 is a 5-pyrazolone residue bound in the 4-position to the R3-N=N-group and in the 1-position through an arylene group to the -N=N-R1 group and particularly dyes of formula <FORM:0902228/IV (b)/3> where n is 1 or 2, R is a benzene or naphthalene residue and R2 is a benzene, diphenyl, naphthalene or 5-pyrazolone residue. Amongst indicated compounds from which R is derived are aminosalicyclic acid, aniline-2,5-disulphonic acid, nitro- and chloro-anilines, 4-amino- 41-acetylaminodiphenyl- 3-sulphonic acid, 2-naphthylamine-4,8-disulphonic acid, dehydrothiotoluidine mono- and di-sulphonic acids, aminoazobenzene mono- and di-sulphonic acids and compounds obtained by coupling the above azo group free amines with coupling components such as 3-methyl-aniline and 1-naphthylamine-6- and -7-sulphonic acids. R may also be derived from diamines such as 4,41-diamino-3,31-dimethoxy-diphenyl or from stilbene or triazole or acetoacet-anilide derivatives. The portion of the dye corresponding to R may also be metallised. Representative of indicated components corresponding to R1 are 2-methoxy-5-methyl-aniline and 2-methoxy-1-naphthylamine monosulphonic acids unsubstituted in the 4-position. Copper and nickel are specified metals. Hydroxyl, alkoxy and carboxy groups are specified metallisable groups. The dyes colour materials such as wool, silk and leather and especially cellulosic materials such as cotton, linen, artificial silk and regenerated cellulose fibres. The dyeings may be metallised on the fibre or in the dye-bath. Examples are provided of the preparation of the dyes and their use in colouring processes. Green and grey shades are obtained on cellulosic materials. Specifications 619,969, 644,883 and 744,666 are referred to.