LIGHT FADING INHIBITOR FOR ORGANIC COLORING SUBSTANCE AND LIGHT FADING INHIBITION

摘要

PURPOSE:To improve the light stability without adversely affecting the hue and purity of an organic coloring substance, especially, a pigment or a dye, by using a compound of a specified formula in combination with said substance. CONSTITUTION:At least one compound of formula I (e.g., a compound of formula II or III) is used in combination with an organic coloring substance. In formula I, R1 is H, an alkyl, a cycloalkyl, an alkenyl or an aryl, R2 is a substitutable group, n is 0-3, and A1-A4 are each H, an alkyl, a cycloalkyl, an alkenyl or an aryl, provided that the case where position 5 or 5' of 3,3'-spirobenzofuran is OH is excluded and the case where position 5 or 5' is an alkoxy when R1 is other than H is excluded. According to the above, the light stability of the organic coloring substance, especially, a pigment or a dye can be improved without adversely affecting its hue and purity. Therefore, the light stability of a colored image which forms a color photographic image can be improved without staining an undeveloped part of a color photographic material.