Silicon-Containing Azo Dyes

Abstract

The dyeing properties and the lightfastness on cellulose acetate rayon of several azo dyes prepared from m-trimethylsilyl- and m-triphenylsilyl- N,N]- bis- (β-hydroxyethyl)-aniline have been examined. The dyes derived from m-triphenylsilyl- N,N- bis-(β-hydroxyethyl)-aniline have been found to lack substantivity for cellulose acetate and to have inferior lightfastness, whereas the dyes obtained from the trimethylsilyl analogue showed fairly good substantivity and very good light fastness. A comparison of the dyeings and the lightfastness of some of the dyes synthesized from m-trimethylsilyl- N, N- bis-(β-hydroxyethyl)-aniline with those of the corresponding dyes obtained from the methyl analogue, which are commercial dyes, has revealed that the substan tivity of the silicon-containing azo dyes is less, but the lightfastness is more, than those of the commercial azo dyes. The reflectance spectra of the 1% shades of some of the azo dyes have been recorded, and the Munsell renotations for hue, lightness, and chroma of the color of the dyes have been determined.