| 摘要 |
PURPOSE:To perform writing having sharp hue using a felt pen of oily ink by incorporating not only a compound represented by a specific formula as an org. coupler but also p-benzyl biphenyl in a thermal color forming layer. CONSTITUTION:A compound represented by formula I (wherein R is a 1-3C alkyl group) is used as an org. coupler. As a basic leuco dye to be used, there is no special limit but a triphenylmethane compound, a fluorane compound, an azaphthalide compound and a fluorene compound are pref. and, other than the coupler and the dye, p-benzyl biphenyl is used as a sensitizer. The use amounts of the org. coupler, the sensitizer and a filler being other component per one pts. of the basis leuco dye are respectively 1-8pts., 3-10pts. and 1-20pts. in usual and a binder is properly used in an amount of 10-25% by wt. of the total solid. |
