摘要 |
PURPOSE:To prevent deterioration due to a plasticizer or light, by providing a thermal color forming layer containing a colorless or light-colored leuco dye being a color forming substance and 2, 4'-dihydroxydiphenylsulfone being a coupler on a support. CONSTITUTION:A substantially colorless or light-colored leuco dye and a coupler based on 2, 4'-dihydroxydiphenylsulfone are dispersed in a binder such as hydroxy ethyl cellulose to prepare a coating solution which is, in turn, applied to a support such as fine paper and dried to prepare a thermal recording material having a thermal color forming layer. As the aforementioned colorless or light-colored color forming substance, there are Crystal Violet lactone and Malachite Green ete. Thc coupler may contains dihydroxydiphenylsulfone having a hidroxyl substitutent at the 2, 2'-positions or 4, 4'-positions thereof. |