| 摘要 |
PURPOSE:To make possible the thermal recording of data using a high sensitivity, low output laser by adding to a thermal layer an infrared absorption color with outstanding infrared laser absorption efficiency and the high efficiency to convert the energy of a laser beam to a thermal energy, regardless of a decrease in the absorption of a visible light. CONSTITUTION:A thermal layer consists of a colorless coloring component A, a colorless coloring components B which becomes tinted through a chemical reaction with the component A and an infrared absorption color. In addition, at least, one of the coloring components is microcapsulated and at the same time, the infrared absorption color is such as expressed by a formula. (L is a methine group or a trimethine or a pentamethine chain coupled by a conjugate double bond; E is 0, S, N-R 4; R<1>, R<4> are independently an alkyl group, an alkenyl group, an alkynyl group, an aryl group, etc.; R<2> is H, an alkyl group, an aryl group, an alkenyl, an alkynyl group, etc.; R<3> is H, a halogen atom, a cyano group, a nitro group, a hydroxyl group, a carboxyl group and its salt, an alkyl group, etc.). |
