| 摘要 |
PURPOSE:To enhance color forming property, by incorporating specified a 4- acylbiphenyl into a thermal color forming layer comprising a colorless or light- colored color forming substance and a color developing substance capable of developing the color of the color forming substance when being heated as main constituents. CONSTITUTION:The thermal recording material comprises a 4-acylbiphenyl of formula I, wherein R is 1-25C alkyl or phenyl, and X is halogen, nitro or 1-4C alkyl, in a thermal color forming layer comprising a colorless or light-colored color forming substance and a color developing substance capable of developing the color of the color forming substance when being heated. The compound of formula I is, for example, 4-acetylbiphenyl, 4-acetyl-4'- nitrobiphenyl or 4-propionylbiphenyl, while the color forming substance may be a xanthene compound, a triarylmethane compound, a spiropyran compound or the like. The color developing substance is a polyvalent metal salt of p- octylphenol, p-t-butylphenol, p-phenylphenol or the like. |
