| 摘要 |
PURPOSE:To effectively prevent a thermal recording material from being colored under the effect of light, by incorporating a specified tetrahydroquinoline derivative into microcapsules. CONSTITUTION:A tetrahydroquinoline derivative of the formula, wherein R<1> is hydrogen, halogen, 1-8C alkoxy, 6-18C aryloxy or 7-18C aralkyloxy, R<2> is 1-15C alkyl, 6-18C aryl or 7-18C aralkyl, and each of R<3>, R<4> and R<5> is hydrogen or 1-4C alkyl, is incorporated in the microcapsules as a core substance, and the amount thereof per unit area of the thermal recording material is preferably 0.05-2g/m<2>. When a UV absorber is used in an appropriate quantity in combination with the derivative, a coloration-preventing effect is further enhanced. |
