直接アゾ染料とスチルベン系ケイ光増白剤の水溶液および綿布上での光退色相互作用

抄録

A fluorescent brightening agent of a stilbene type C. I. FBA 24 (F_BN) was found to enhance the fading rate of a blue direct azo dye C. I. (DB15) in aqueous solution, on the irradiation with a high pressure mercury lamp. On the other hand, DB15 depressed the fading of F_BN. Fading of both DB15 and F_BN was depressed in aqueous solution by the irradiation using a low mercury lamp. Similar effect was also observed in the measurement on cotton fabric, on the irradiation with a high pressure mercury lamp, whereas F_BN depressed the fading of the dye on the irradiation with a low pressure mercury lamp. These effects were found in the concentration range of the dye bath of F_BN higher than 1×10^-5 mol/l. The dye accelerated the fading of F_BN at the early stage of the reaction when exposed to a low pressure mercury lamp, a high pressure mercury lamp or a xenon lamp.