PHOTOLYTIC BEHAVIOR OF SOME POPULAR DISPERSE DYES ON POLYESTER AND NYLON SUBSTRATES

The photodegradation products that form when disperse red 1, red 17, and blue 3 dyed fabrics and films are exposed to carbon arc and xenon arc light sources have been identified. The effects of black panel and dye carrier on the nature of the degradation products and the fading process itself were also studied. The results of this research indicate that the same photodegradation products occur in comparisons involving carbon arc versus xenon arc exposures, polyester versus nylon substrates, black panel versus no black panel exposures, and exposures of carrier dyed versus no carrier dyed PET. It is clear that photo-reduction pathways account for the products that form when the two azo disperse dyes (red 1 and red 17) photofade, but photo-oxidation characterizes the fading of the anthraquinone disperse dye blue 3. The photodegradation products were determined with the aid of GC mass spectrometry and by TLC comparisons with authentic samples.