| 摘要 |
PROBLEM TO BE SOLVED: To provide a multi-color thermal recording material which shows a sharp color tone of a developed color, efficient two-color separability and the high keeping quality of a color-developed image at a low temperature. SOLUTION: The multi-color thermal recording material has a thermal recording layer composed of two or more kinds of normally colorless or pale-color electron-donating dye precursors which develop a color in varying color tone and an electron-receiving compound which develops a color in the electron- donating dye, formed on a support. The electron-donating dye precursor to be added is a 3-di-n-butylamino-6-methyl-7-bromofluoran. In addition, the electron-receiving compound to be added is at least one kind selected from among a 2,4-bis(phenylsulfonyl) phenol and the like, and a bis (3-allyl-4- hydroxyphenyl) sulfone. Further, at least one or more kinds of the electron- donating dye precursor are allowed to be present in the thermal recording layer, in the form of a particle with a color development adjusting layer obtained by polymerizing a chemical compound having an unsaturated carbon bond, formed on the surface. |
