| 摘要 |
PURPOSE:To enable recorded images to be read by an OCR, a bar code reader using a semiconductor laser or the like, by using a leuco dye of a specified formula, a color reaction agent consisting of a specified compound, and a zinc compound. CONSTITUTION:This thermal recording material utilizes a color forming reaction between a leuco dye and a color reaction agent capable of developing the color of the dye on making contact with the dye. At least one of the leuco dyes showing light absorption in a near infrared region is a compound of formula (I), wherein each of R1, R2, R3 and R4 is hydrogen or a subst. or unsubst. alkyl, each of R5 and R6 is hydrogen or subst. or unsubst. phenyl, and R7 is a subst. or unsubst. alkyl or subst. or unsubst. phenyl. At least one of the color reaction agents is a compound selected from salts of a 2-acyloxybenzoic acid compound, a 2-acyloxy-1-naphthoic acid compound, a 1-acyloxy-2-naphthoic acid compound or 3-acyloxy-2-naphthoic acid compound with lead, calcium, magnesium barium or strontium. The recording material further comprises a zinc compound, which may be, for example, lead stearate, lead palmitate, lead behenate, lead oxide, lead hydroxide or lead chloride. |
