| 摘要 |
PURPOSE:To provide the titled sheet excellent in color forming sensitivity and preservation stability, obtained by providing a heat-sensitive recording layer containing a color-formable lactone compound, an acidic substance and a specific sensitizer on a sheet substrate. CONSTITUTION:1pt.wt. color-formable lactone compound[e.g., 3,3-bis(p-dimethylaminophenyl)phthalide](A), 2-30pts.wt. colorless or light-colored acidic substance (e.g., 4-phenylphenol) (B) and 0.005-2pts.wt. to 1pt.wt. component B of a sensitizer comprising an ester shown by formulae I -IV (wherein R1 and R2 are each H, 1-18C alkyl, aryl, aralkyl; R3 is H or 1-18C alkyl; R4 and R5 are the same as R1 but are not H simultaneously; R6 is H, 1-18C alkyl or aralkyl) (C) are each added to a separate aqueous solution of a water-soluble high-molecular compound (e.g., PVA) and the resulting mixture is milled and dispersed so as to reduce a particle size to 3mum or less by a milling mixer to obtain a coating liquid. In the next step, this coating liquid is mixed and applied onto a substrate in such a manner as to adjust the amount of component A to 0.1-0.6g/m<2> and dried at a room temp. -50 deg.C. |
