Effects of Substituent and Aggregation on the Photofading of Some Azo Pyridone Dyes on Polyester Substrates

Abstract

We obtained a series of monoazo dyes by diazotizing 2-hydroxy-4-methyl-5-cyano- 6-pyridone (as a coupling component) with mono- and di-substituted anilines, and we determined the electronic absorption spectra of the dyes, dyeing properties, fastness of the dyed fabrics, fading rate of the dyes, and their color parameters. We found that the series of monoazo pyridone dyes can be applied to the polyester fibers. We con cluded that adding electron-withdrawing substituents to anilines increases the pho tostability and improves the sublimation fastness of these azo dyes on polyester, while introducing the β-hydroxyethyl group to the coupling component results in an increase in the fading rate. On the other hand, when the dye yields a first-order fading rate curve, its lightfastness is very low.

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