THERMAL RECORDING MATERIAL

PURPOSE:To obtain a thermal recording material with excellent high speed recording properties, little change in color of the skin when it is brought into contact with NOX gas etc., and excellent resistance to environment by using a highly sensitive color developer and 4-benzyloxy-4'-(2,3-epoxy-2-methylpropoxy) diphenyl sulfone. CONSTITUTION:In a thermal recording material wherein a heat-sensitive color developing layer contg. a leuco dye and a color developer developing color of the leuco dye at heating is provided, at least one of 1,7-di(4- hydroxyphenylthio)-3,5-dioxaheptane and/or 1,5-di (4-hydroxyphenylthio)-3- oxaheptane is used as the above described color developer. In addition, 1.5-0.2 pts.wt. of 4-benzyloxy-4'-(2,3-epoxy-2-methylpropoxy) diphenyl sulfone based on 1 pt.wt. of above described leuco dye is incorporated as a stabilizer.