| 摘要 |
PURPOSE:To reduce thermal energy for melting or dissolution and contrive a higher sensitivity, by using a specified compound as a leuco dye which is a main constituent of a thermal color forming layer and using a color developer the melting point of which is limited. CONSTITUTION:3-(N-n-Octyl-N-iso-propyl)amino-6-methyl-7-anilinofluo-ran of formula (1) or the like is used as a leuco dye and a color developer with a melting point of 60-120 deg.C is used, in a thermal recording material provided with a thermal color forming layer comprising as main constituents a normally colorless or light-colored leuco dye and a color developer for developing the color of the dye when being heated. The leuco dye has a melting point of 116-118 deg.C which is approximate to the melting point of the color developer and has high reactivity, so that a highly sensitive material can be obtained. |
