| 摘要 |
PURPOSE:To obtain a sharp bluish black or blackish blue image without generating fog in a blank part by using one kind of a fluorene derivative represented by a specific chemical formula and one kind of an azaphthalide derivative represented by a specific chemical formula in a thermal recording layer as basic dyes in a specific combination. CONSTITUTION:In a thermal recording material utilizing the color forming reaction of a colorless or light-colored basic dye and an org. or inorg. developer and bringing both color forming substances into contact with each other under heating to obtain a recording image, at least one kind of a fluorene derivative represented by chemical formula I (wherein R1 and R2 are an alkyl group or an aryl group, R3 and R4 are a hydrogen atom or an alkyl group and T and P are a hydrogen atom or an alkyl group) and at least one kind of an azaphthalide derivative represented by chemical formula II (wherein A and B are a carbon atom or a nitrogen atom and R5-R8 are a hydrogen or an alkyl group) are used as basic dyes and the azaphthalide derivative is contained in an amount of 0.1-5% by wt. of the fluorene derivative. |
