STUDIES ON THE DYEING PROPERTIES OF ACID AZO DYES (III)

The dyeing properties of azo acid dyes having the same skeletal structure as p-X-aniline→J-acid (6-amino-l-naphthol-3-sulphonic acid) [alkali coupling and acid coupling], where X is H, SO3H, SO2NH2, COOH, COOC2H5, Cl, CH3, OCH3, NO2, NH2, NHCOCH3, respectively, are examined.As to the shade on wool dyeings, the alkali coupling dyes are brighter than those of the corresponding acid coupling dyes.All of these dyes have a considerable affinity for wool in the neutral dyeing bath. The exhaustions (SDC Method)of these dyes are higher than in the corresponding p-X-aniline→γ-acid.The influence of substituent group to light fastness is the same as in the case of the p-X-aniline→J-acid.