Synthesis and studies of some acid dyes

Investigations of the adsorption of acid dyes containing acetoacetanilide a nd pyrazolone by woollen fabric have been carried out, It has been found th at the adsorption levels; are unexpectedly different for various dyes, Both acetoacetanilide and pyrazolone colorants have good fastness of dyes to wa shing light and heat,The light fastness of the dyes was found to depend on the influence of the substituents on the electron density around the azo gr oup, An electron accepting substituents (o-COOH) afforded a good values of light fastness, A correlation between light fastness and dye absorption spe ctra has been suggested, which showed that pi-pi* electronic transition is an important parameter in determining the stability of the system. The visi ble absorption spectra and Munsell renotations of all the dyes showed that the colours of dyes lie in the range of yellow -red -green.