| 摘要 |
PURPOSE:To obtain a fine color image, prevent the deterioration of a processing soln. and enable automatic processing, in a method of utilizing a compound which reduction-colors by the oxidation of silver in a silver image, by applying a substance required to accelerate and maintain the reduction to the silver image. CONSTITUTION:An aqueous soln. A is prepared contg. an org. cationic compound such as tetrazolium salt which reduction-colors and is represented by formula I, II or III [where each of R<1> and R<2> is optionally substituted aryl or a 5- or 6-membered ring contg. N, S, O, Se or the like, R<3> is the same as R<1>, OH, H or the like, X<-> is an anion, each of D and E is a divalent group, and (n) is 1-5]. On the other hand, an aqueous soln. B is prepared contg. a compound which accelerates and maintains the above-mentioned reaction. The compound is thiosulfate, thiourea or the like forming a water soluble complex with silver ion or diol represented by formula IV [where (m) is 2-13, Z is O or S, 1/3 of total Z is S, and a moiety of two or more connected S units is surely contained]. The solns. A, B are mixed before use and applied to a silver image by a necessary amount, and the image is color processed. Thus, the life of the processing soln. is elongated with a reduced amount of chemicals, the recovery of silver is facilitated, and automatic processing is enabled. |
