| 摘要 |
PURPOSE:To prevent a blushing phenomenon from occurring, by incorporating one or more specified benzenesulfonamide compounds into a recording layer basically comprising a fluoran compound, an acidic substance for developing the color of the fluoran compound when being heated and a binder. CONSTITUTION:In a thermal recording paper wherein the recording layer basically comprising a colorless or light-colored fluoran compound, an acidic substance for developing the color of the fluoran compound when being heated and a binder is provided on a base, one or more benzenesulfonamide compound of the formula, (wherein R1 is H, lower alkyl or halogen, R2 is H, 1-8C alkyl, cyclohexyl or phenyl which may be substituted, R3 is 1-8C alkyl, cyclohexyl or phenyl which may be substituted, and R2 and R3 may form a saturated ring with N, with the proviso that R1 is not lower alkyl when it is located at 4-position, are incorporated in the recording layer.) Preferably, per 1pt.wt. of the color developer, the benzenesulfonamide is used in a quantity of 0.3-3pts.wt., the acidic substance is used in a quantity of 4-6pts.wt. and the binder is used in a quantity of 0.5-1pt.wt. The color former, the acidic substance and the additive compound are dispersed in water or an organic medium containing the binder with an aqueous solution of the binder as a medium by using a dispersing machine, followed by milling to produce a dispersed liquid with a particle diameter of preferably 3-5mum. The thus obtained thermal recording paper is extremely excellent in heat-sensitive characteristics, resistance to decoloration due to heat or moisture and water resistance, and is free from whiting phenomenon. |
