To provide a cosmetic that can dye the hair quickly, uniformly and efficiently, without damaging the hair or skin, and also has good long-term storage stability in a container for a cosmetic product, and exhibits good dyeability.SOLUTION: A photosensitive hair dye is an aqueous solution in which a silver salt, in the form of one or more of silver sulfate, silver lactate, and silver citrate, at a rate of 0.01% to 5.0%, and a phosphoric acid of 0.01% to 15.0% are dissolved therein.SELECTED DRAWING: Figure 2【課題】地肌や毛髪を傷めることなく、毛髪を手早く、均一に効率よく染色でき、化粧品に使用される容器内での長期保存安定性もよく、染色性に優れた化粧料の提供。【解決手段】銀塩が、硫酸銀、乳酸銀、クエン酸銀のいずれか、または二種以上で０．０１％から５．０％と、リン酸０．０１％から１５．０％が溶解している水溶液であることを特徴とする感光性染毛料。【選択図】図２
