| 摘要 |
PURPOSE:To enable reading by an optical reader using a semiconductor laser or the like, by providing a thermal color forming layer comprising a specified fluoran leuco dye, a color developer, titanium dioxide and a fluorescent dye, on a base. CONSTITUTION:A leuco dye of formula I (each of R1 and R2 is hydrogen, a halogen or 1-5C alkyl, and R3 is formula II, formula III or the like), a color developer, titanium dioxide and a fluorescent dye are separatedly ground and dispersed together with an aqueous binder solution by a dispersing machine such as a ball mill, and the dispersed liquids are mixed with each other to prepare a coating liquid for forming a thermal color forming layer. The coating liquid is applied to a base such as a paper, a synthetic paper and a plastic film, followed by drying and calendering to provide the thermal color forming layer, thereby obtaining a thermal recording material. The recording material enables reading of images by an image reader using a general-purpose semiconductor laser or the like. |
