| 摘要 |
PURPOSE:To provide a thermal recording material having high sensitivity, by containing a coupler being at least one compound selected from compounds represented by formulae (I), (II) and a sensitizer being an 1, 4- dihydroxynaphthalene derivative represented by formula (III) in a thermal color forming layer. CONSTITUTION:In a thermal recording material provided with a thermal color forming layer based on a leuco dye and a coupler capable of allowing said leuco dye to develop a color under heating, an 1, 4-dihydroxynaphthalene derivative represented by formula (III) is a compound with m.p. of 70-120 deg.C and melted sharply at this temp. and excellent in the solubility and compatibility with the coupler or the leuco dye and, therefore, the color forming sensitivity thereof becomes high. The couplers represented by formulae (I), (II) can be together used along with an electron acceptive substance reacting with the leuco dye under heating to allow the same to develop a color and, for example, a phenolic substance, an org. or inorg. acidic substance or esters or salts thereof are used. Further, as an auxiliary additive component, a filler, a surfactant, a heat-meltable substance (or lubricant) or the like can be together used. |
