PURPOSE: To obtain a high-quality thermosensitive recording sheet having a high sensitivity, little possibility of adhesion of foreign matter, and a superior shelf stability under high-temperature and -humidity conditions in a thermosensitive recording sheet containing bis(p-methylbenzyl)oxalate as a sensitizer.
CONSTITUTION: In a thermosensitive recording sheet formed by providing a color forming layer mainly composed of an electron donative colorless dye and an electron accepting compound reacting with said dye to form a color under heat on a substrate, bis(p-methylbenzyl)oxalate is incorporated in said color forming layer. The thermosensitive recording sheet has an extract pH of 7.0-9.0 (based on a cold water extraction method as an JIS P 8133 method). The combination of the thermosensitive recording layer containing bis(p- methylbenzyl)oxalate with the thermosensitive recording sheet having an extract pH of 7.0-9.0 ensures a high-quality thermosensitive recording sheet having a high sensitivity, little possibility of adhesion of foreign matter, and a superior shelf stability under high-temperature and -humidity conditions.