色素の光退色-光化学反応性と耐光堅牢度を結びつける試み-

本研究的目的是从理论上考察染料或染色织物的光化学反应的牢度，通过研究染料量与其功能之间的关系，即颜色的变化。选择酸性蓝83用于实验，因为其用于染色3级蓝色标度，所述3级蓝色标度是在耐光色牢度测试中评估颜色变化的标准。蓝色水溶液或蓝色染色织物的色差通过比色法测量，并根据以下情况进行视觉判断：A ;光反应产物无色的脱色模型，B ;光反应产物黄色的变色模型，和C ;伴随变暗的实际现象。分析了色差的判别阈值及其与染料用量的关系，在A色情况下，CIE L^*a^*B^* 色系中色差的判别阈值ΔE为2 × 3。该值对于蓝色和黄色是相似的。染料在水溶液和织物上的用量为2 × 3ΔE，深蓝色是浅蓝色的10倍。对于黄色，2 <$3 ΔE所对应的染料量，深色是浅色的100倍。同一颜色变化所需的染料量因色相不同而不同。色差判别阈值B为6，C为9 × 10，对应的染料用量也大于A。通过测定色差系数和染料在膜中光反应量子产率，考察染色织物的色牢度与染料光反应过程的关系。

This study aims as inspecting theoretically the fastness of dyes or dyed fabrics in terms of their photochemical reactions by investigating the relationship between dye quantity and their function ; a change in colour. Acid Blue 83 was selected for experiments, because this is used for dyeing 3 grade of Blue Scale that is the standard for assessing a change in color at the test for color fastness to light. The color difference of blue aqueous solutions or of blue-dyed fabrics was measured spectometrically, and was judged visually on the following cases, A ; a decolorization model in which photo reaction products are colorless, B ; a discoloration model in which photo reaction products are yellow, and C ; an actual phenomenon accompanied with darking. The discrimination threshold of color difference and their dependence on dye quantity was analyzed.In case of A, the discrimination threshold of color difference (ΔE) was 2〜3 in CIE L^*a^*b^* color system. This values was similar for blue and for yellow. The quantity of dye in aqueous solution and on fabric, corresponding to 2〜3ΔE, was 10 times for deep blue as that for light blue. As for yellow, the quantity of dye corresponding to 2〜3ΔE was 100 times for deep color as that for light colour. The quantity of dye required for the same color change was different with the color hue. The discrimination threshold of color difference was 6 in case of B, 9〜10 in case of C, and the corresponding quantity of dyes is also larger than that for case A.The relationship between color fastness degree of dyed fabric and photo-reaction process of dye will be examined by measuring coefficient of color difference and quantum yield for photo-reaction of dye in film.