| 摘要 |
PURPOSE:To obtain a reversible thermal coloring composition which colors and discharges due to heating by blending higher fatty acid having hydroxyl as a discharge promoter with an electron-donative color developer and an electron-receptive compound as principal ingredients. CONSTITUTION:0.5 to 50wt.% of higher fatty acid having hydroxyl such as 2-hydroxy butyric acid or 2-hydroxy-2-methylpropanic acid for an electron- donative color developing compound such as a triphenyl methanepthalide compound, an electro-receptive compound such as an organic phosphate compound, are evenly dispersed or dissolved in water or an organic solvent, with said electron-receptive compound, and if desired, with a binder. Thus, a reversible thermal coloring composition is prepared. This reversible thermal coloring composition is applied on the surface of a substrate as plastic film or synthetic paper, and then is dried to form a laminated thermal recording layer. This reversible thermal recording medium obtained has an image with a sharp contrast and an extended discharge temperature range, contributing toward the improvement of image erasing properties. |
