| 摘要 |
PURPOSE:To enable repeated color forming and decoloring behavior with high sensitivity to thermal stimuli, by dissolving both an electron-donative color- developing organic compound having a lactone ring and an electron acceptive compound having a phenolic hydroxyl group in a liquid-crystalline medium. CONSTITUTION:An electron-donative color-developing organic compound having a lactone ring and an electron-acceptive compound having a phenolic hydroxyl group are dissolved in a liquid-crystalline medium. The organic compound per se is a colorless or light-colored coloring matter precursor (so-called lueco dye), and is developed into a color by opening of the lactone ring. The organic compound having the lactone ring may be a triphenylmethanephthalide, a fluoran, a thiofluoran, an indolylphthalide, a Rhodamine lactam, an azaphthalide or the like. The electron-acceptive compound having the phenolic hydroxyl group may be tert-butylphenyl, nonylphenol, dodecylphenol, styrenated phenol or the like. |
