| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat-sensitive recording developer composition of high sensitivity, generating little texture fog, having superior storage stability for a recorded image, in particular, superior resistance to humidity, resistance to heat and resistance to plasticizer. SOLUTION: The developer composition of the heat-sensitive recording material is composed of mixture composed of at least one kind selected out of a sulfonyl compound represented by formula (1) or out of its polyvalent metal salt and one kind out of the sulfonyl compound represented by formula (3). In formula (1), X represents a hydrogen atom and an alkyl group, R1-R3 represent a hydrogen atom, a hydroxyl group, an alkyl group or a cycloalkyl group, R4-R6 and R8-R10 represent a hydrogen atom, a halogenated atom, an alkyl group or a cycloalky group and R7 represents a hydrogen atom and formula (2). |
