| 摘要 |
PURPOSE:To make reversible color change between a specific color and a different color possible corresponding to temp. change by combining a reversibly thermal color-changeable material forming a color by heating with a reversibly thermal color-changeable material fading by heating. CONSTITUTION:In a reversibly thermal color-changeable medium containing a reversibly thermal color-changeable material forming a color by heating and a reversibly thermal color-changeable material fading by heating, both materials are separately microencapsulated. An electron acceptive compound can be selected from developers generally used in thermal paper in a system fading by heating. For example, a phenolic compound, a thiophenolic compound, a thiourea derivative, an org. acid and a metal salt thereof or the like can be used. In a system forming a color by heating, a selecting range is narrow as compared with the aforementioned fading system and, as an especially pref. electron acceptive compound, there is dodecyl gallate. |
