| 摘要 |
PROBLEM TO BE SOLVED: To obtain a thermal recording medium having small aging skin fog and high whiteness by incorporating water insoluble salt of blue basic dye and anionic fluorescent whitening agent in at least one layer of an undercoating layer provided between a support and a thermal recording layer and a thermal recording layer. SOLUTION: Water insoluble salt of blue basic dye and anionic fluorescent whitening agent is contained at least in one of a thermal recording layer, an undercoating layer and a protective layer. This salt is formed by mixing the blue dye dissolved in water wit equal amount of the whitening agent to the blue dye. Using ratio of leuco dye to colorant in the thermal recording layer is generally preferably 1 to 4 pts.wt. of the colorant to 1 pt.wt. of the leuco dye. To enhance recording sensitivity, sensitizer is added, and to enhance preservability of a recorded image, preservability modifier is added. |
