| 摘要 |
PURPOSE:To obtain printing quality which is excellent in both raw shelf stability and stability of a coloring image by high sensitivity by a method wherein a specific salycilic acid derivative or its metal salt is contained in a thermal coloring layer and para-benzylbiphenyl is contained as a sensitizer. CONSTITUTION:A thermal coloring layer containing an electron donative colorless dye and an electron acceptive compound is provided onto a base material. A salycilic acid derivative having an aryl oxyalkyloxy radical as a substituent or its metal salt is contained in the thermal coloring layer. Further, para- benzylbiphenyl is contained as a sensitizer. In that case para-benzylbiphenyl and amido compound are jointly used as the sensitizer. Further, the salycilic acid derivative should be preferably expressed by the formula fly. In the formula, however, Ar represents an aryl radical, and X represents a hydrogen atom, an alkyl radical an alkoxy radical or a hologen atom. M represents an n-valued metal atom, and m, n represent integers. This recording material is enough in coloring density and a colored pixel is extremely stable. It hardly generates change in color even by irradiation with light, heating, and humidification for a long time. |
