| 摘要 |
PURPOSE:To prevent the obstruction of color development or lowering in sensitivity on a thermal color forming layer, by containing bis(4-glycidyloxyphenyl) sulfone in the overcoat layer on the thermal color forming layer containing a dye precursor and a coupler as main constitutional elements. CONSTITUTION:A thermal color forming layer containing a colorless or light- colored dye precursor and a coupler allowing said dye precursor to form a color through the reaction with the dye precursor at the time of heating as main constitutional elements is provided on a support and, further, an overcoat layer based on a water-soluble polymer is provided thereon. Then, bis(4- glycidyloxyphenyl)sulfone is contained in said overcoat layer. If said bis(4- glycidyloxyphenyl)sulfone is contained in the thermal layer in a ground state, greening fog is generated in a white part with the elapse of time or black fog is abruptly generated under a high temp. and high humidity atmosphere and, therefore, if said compound is allowed to be present in the overcoat layer in the ground state, chemical resistance and color forming sensitivity can be developed effectively. |
