GB844398A - Improvements relating to chromium containing benzene-monoazo-pyrazolone dyestuffs and their use - Google Patents

Abstract

The invention comprises chromium complexes of dyestuffs, free from sulphonic acid groups, of formula: <FORM:0844398/IV (c)/1> where R is a substituent which does not hinder the diazotisation of the primary amino group and the coupling of the diazonium compound with the pyrazolone derivative or the formation of the chromium complex by way of the carboxyl group, B is the residue of a 5-pyrazolone which may be alkyl or aryl substituted in position 1 and residue A may be further substituted. The dyestuffs are made by conventional methods in which the appropriate diazotised aniline and pyrazolone are coupled and the product chromed. Advantageously 1, 2-complexes are obtained. Indicated as values for R are halogen atoms, alkyl, aralkyl and aryl groups, trifluoromethyl and cyano groups, alkyl-, aralkyl- and aryl-ether, -thioether and sulphonyl groups, alkyl- or arylketo groups, dialkyl- and acyl-alkyl amino groups, alkyl-, cycloalkyl- and arylsulphoxide groups and N-substituted sulphonamide groups. Preferred values for R are halogen atoms and alkyl groups e.g. chlorine, methyl and ethyl groups. Indicated as further substituents are halogen atoms, alkyl, alkoxy, nitro, hydroxy, acylamino, alkyl- or aryl-sulphonyl, acyl, carboxylic acid amide or arylamide groups and sulphonamide and N-substituted sulphonamide groups. Chiefly 3-alkyl-5- pyrazolones, optionally substituted in the 1-position especially 3-methyl-5-pyrazolones are used. Mixed chromium complexes may also be obtained in which in the final product the chromium atom is combined with a molecule of an aniline-pyrazolone dyestuff indicated above and with a molecule of another complex, former having no sulphonic acid groups such as an #s, #s1-dihydroxy- or #s-hydroxy, #s1-carboxy-azo dyestuff or an uncoloured compound such as an aryl #s-hydroxy-carboxylic acid. The mixed complexes are made by usual methods. The products dye natural and synthetic polypeptide fibres, especially wool, silk, polyamide and polyurethane fibres and leather giving greenish-yellow shades. Textiles are dyed with the alkali metal or ammonium salts of the dyestuffs. Some of the dyestuffs may be used for dyeing nitro or acetyl cellulose lacquers and acetyl cellulose spinning masses. In examples illustrative of the preparation of the dyestuffs and their use in dyeing wool and polyamide fibres the diazo components used are 3-methyl-, -ethyl-, -methanesulphonyl- and -chloro-, 3, 5-dimethyl-, -dichloro- and -dibromo, 3-methoxy -6- chloro- and 3-chloro -5- ethyl- 2-aminobenzene-1-carboxylic acids and the coupling components are 1-methyl-, -(a -phenethyl)-, -butyl-, -benzyl-, -phenyl-, -(21-chloro- and -ethyl-, 31-sulphamido- and -chloro- and 41-methyl-, -methoxy- and -ethoxy-phenyl)-3-methyl -5- pyrazolones and 3-methyl -5- pyrazolone. Specification 820,502 is referred to. Reference has been directed by the Comptroller to Specifications 692,073, 797,046 and 798,746.