| 摘要 |
PURPOSE:To obtain a reversible thermal color developing composition which can be used as solvent type coating fluid and be recorded at a high speed when a thermal color developing layer is formed by using specific compound as elec tron accepting developer. CONSTITUTION:A reversible thermal recording medium has a recording layer formed of reversible thermal color developing composition containing developer and color developing agent. As the developer, i.e., electron accepting developer, CH2 n+1-X-PO(OH)2 is used. In the formula, X is -OCH2-, -SCH2-, -CH(NH2)-, -CH(COOH)-, -CONHCH2-, -C6H4-, and n is integer of 6-23. When such a composition is heated to a melting temperature or higher, the composition instantaneously develops a color, and its color developing state is stably existed at the ambient temperature. However, the composition of the developed state is decolored when heated to a temperature lower than the developing temperature, and its decolored state is stably existed at the ambient temperature. |
