| 摘要 |
PURPOSE:To enhance preservability such as light resistance and heat resistance by providing a thermal recording material by supporting two leuco dyes and color developers for developing the leuco dyes into colors by making contact therewith when being heated, on a support by binding the dyes and the developers by a binder. CONSTITUTION:Leuco dyes of formulas I and II (R is an alkyl, each of R1 and R2 is an alkyl or aryl, R3 is H, a lower alkyl, alkoxyl or aralkyloxyl, R4 is H, a lower alkyl, halogen or the like, R5 is H, a halogen or the like, and each of R6 and R7 is a lower alkyl) and color developers for developing the dyes into colors upon making contact therewith when being heated are mixed with a binder to prepare a coating liquid. The coating liquid is applied to a support, followed by drying to provide a recording layer, thereby producing a thermal recording material. The recording material has strong absorptivity throughout the wavelength range from a longer wavelength part of the visible region to a near infrared region. |
