出版社：The Society of Photographic Science and Technolgy of Japan
摘要：Photo-fading reactions of developed color photographic dyes (azomethine dyes) are remarkably affected by traces of impurities like carbonyl compounds (CCPD). Reaction kinetics of model dyes-CCPD solutions in ethanol or benzene are investigated by the steady state method. In these solutions typical photo-fading of the dyes are observed on excitation of CCPD by near ultraviolet light. In cases of simple CCPD such as acetone, acetophenone and benzophenone, the dye fading reactions are promoted by degassing solutions markedly and proceed as near zero order reaction. The quantum yields of the fading reaction are nearly 1 in the all cases. It is estimated that the dyes fade by the following mechanism predominantly. Firstly ketyl radicals of CCPD are produced by abstraction of a-hydrogen of ethanol by the lowest triplet state CCPD. Secondarily the ketyl radical adds a hydrogen to an azomethine group and the azomethine radical is produced. Thirdly the radical abstracts an another hydrogen from ethanol and the leuco dye is produced.
