| 摘要 |
PURPOSE:To provide a thermal recording material having high sensitivity and excellent image reliability, by using a leuco dye having a melting point of 60-140 deg.C and a specified structure and a phenylurea compound as a color developer for the leuco dye, in a thermal color forming layer. CONSTITUTION:A leuco dye of general formula (I), wherein R1 is hydrogen or 1C or higher alkyl, R2 is 5C or higher alkyl, R3 is hydrogen or methyl, and R4 is hydrogen, halogen or trifluoromethyl, having a melting point of 60-140 deg.C and a color developer consisting of a phenylurea compound of general formula (II), wherein R1 is hydrogen, alkyl, haloalkyl, acyl or halogen, R2 is hydrogen, Z is sulfur or oxygen atom, while R2 represents hydrogen only when Z is oxygen. The above-mentioned components are applied for the titled material is which, ordinarily colorless or slightly light colored leuco dye, and thermal coloring layer provided with a coloring agent capable of simultaneous thermal color developing the leuco dye as its main constituent are provided on a supporter. |
