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-

这项研究的目的是通过研究染料数量与其功能之间的关系，从理论上检验染料或染色织物的光化学反应的牢度；颜色的变化。选择酸性蓝83进行实验，因为它用于染色3级蓝色标尺，这是在耐光色牢度试验中评估颜色变化的标准。用分光计量法测定了蓝色水溶液或蓝染织物的色差，并根据以下情况进行了目测判断：A；光反应产物为无色的脱色模型B；光反应产物为黄色的变色模型C；伴随变暗的实际现象。分析了色差辨别阈值及其与染料用量的关系，以A为例，L^*a^*b^*色系的色差辨别阈值(ΔE)为2~3。蓝色和黄色的此值相似。深蓝的水溶液和织物上的染料量相当于2~3ΔE，是浅蓝的10倍。对于黄色，2~3ΔE对应的深色染料的量是浅色的100倍。同一颜色变化所需的染料数量随色调的不同而不同。色差辨别阈值B为6，C为9~10，相应的染料用量也大于A。通过测量色差系数和染料在薄膜中的光反应量子产率来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.