| 摘要 |
PURPOSE:To enable an excellent coloring property, raw shelf life, and shelf life of a recording image to be obtained by a method wherein a specific fluorane derivative, alpha-naphthoeic acid and/or its zinc salt are combined. CONSTITUTION:Fluorane derivative as expressed by the formulas I-III are used as basic dye, and alpha-naphthoeic acid and/or its zinc salt are used as color agent. In the formulas, R1 and R3-R6 respectively indicate C1-C6 alkyl radical, and R2 indicates C1-C6 alkyl radical, C2-C6 alkoxyalkyl radical, cyclopentyl radical, cyclohexyl radical, tetrahydrofurfuryl radical or p-tolyl radical. Further, R1 and R2 together with adjacent nitrogen atom may form pyrrolidine ring or piperidine ring. Furthermore, X indicates methyl radical, and Y indicates chlorine atom, fluorine atom or trifluoromethyl radical, n indicates 0, or an integer of 1 to 2. Thereby, an excellent coloring property, raw shelf life, and shelf life of a recording image can be obtained. |
