| 摘要 |
PURPOSE:To obtain a thermal recording material excellent in thermal response and having high sensitivity, by containing a compound represented by a specific formula in the thermal recording material, which contains a usually colorless or light colored dye precursor and a developer allowing said dye precursor to form a color through the reaction therewith at the time of heating, as a sensitizer. CONSTITUTION:A sensitizer represented by formula (I) (wherein X is hydrogen or OR' and R and R' are a substituted or non-substituted cycloalkylcarbonyl group) is usually added in an amount of 5% by wt. of a normal developer. The addition amount of said sensitizer is pref. 10-400wt% and especially pref. 20-300wt%. If the addition amount thereof is below 5wt%, sensitivity enhancing effect is insufficient and, if more than 400wt%, there is often an economically disadvantageous case. As a dye precursor, a triphenylmethane compound, a fluorane compound, a diphenylmethane compound, a thiazine compound, a spiropyrane compound, etc. are designated. As the developer, an acidic substance generally used in thermal paper, that is, an electron acceptive compound is used and, especially, a phenol derivative and an aromatic carboxylic acid derivative are used. |
