| 摘要 |
PURPOSE:To obtain a thermal recording material with a high color formation sensitivity and preservability without a protection layer by adding a combination of a color former consisting of a specific fluoran compound and a color developer of a spacific sulfone compound to a thermal color forming layer. CONSTITUTION:A color former consisting of a fluoran dericative shown by the formula I and a color developer of a sulfone compound shown by the formula II are added. The sulfone compound shown by the formula II is used at a ratio of 1-5pts.wt., preferably 2-3pts.wt. based on one pt.wt. of the fluoran derivative shown by the formula I. That is, each one of a fluoran color, a color developer, a bonding agent, a filler and other additive alone, or a mixture of either one of the former and other ingredients other than the fluoran color and a fluoran color are added respectively to an aqueous medium together with an aqueous solution of polyvinyl alcohol. After this, the resulting mixture is pulverized and dispersed by a disperser such as a ball mill, an attrition or a paint conditioner. Next each dispersant is added to prepare a thermal color formation layer coating fluid, and this fluid is applied to the surface of a support such as paper and dried, thus making a thermal recording material. |
