| 摘要 |
PURPOSE:To contrive to enhance the solubility of a color former in a solvent for a pressure-sensitive copying paper and the light resistance of the copying paper or a thermal recording paper and reduce spontaneous color development, by incorporating a specified phthalide compound into a recording material as a color former. CONSTITUTION:An azaphthalide compound of the formula, wherein each of R<1>- R<4> is a 1-4C alkyl group, R<5> is a 5-8C alkyl group, one of X and Y is -N= and the other is -CH=, is used as a color former. The pressure-sensitive copying paper is produced by dissolving the color former in a solvent, emulsifying or encapsulating the resultant solution in a binder, and applying the resultant material to a paper. On the other hand, the thermal recording paper is produced by pulverizing the color former and an organic color developer, and applying the pulverized material to a paper or a film together with a binder. |
