Effect of Substrates on Action Spectra of Fading of a Selected Disperse Dyestuff under Light Radiation

Abstract

The characteristics of fading of nylon, polyester and cellulose triacetate fabrics dyed with C I Disperse Blue 79:1 were investigated on a radiant energy basis by exposure to monochromatic light. Action spectra were compiled to show the strong effect of substrate on the fading with respect to radiant wavelength. Peaks were observed with maxima at 246 nm on cellulose triacetate, 310 nm on polyester and 262 nm on nylon in the fading. The nylon substrate caused the least light-fastness compared with the polyester and cellulose triacetate substrates, showing a wide wavelength range in the fading response. Moreover, it was estimated through color change examinations that the reduction of the nitro group to the amino group occurred on the nylon substrate, whereas the destruction of the azo group of the dye prevailed on the polyester and cellulose triacetate substrates under light irradiation.