Patent ID: 8097560

Claim:
A heat-sensitive recording material, comprising: a substrate having a front surface and a back side, a heat-sensitive color developing layer containing a leuco dye and developers on the front surface of the substrate, wherein as the developers 4-hydroxy-4′-allyloxydiphenyl sulfone is used in combination with any one of a first diphenyl sulfone compound represented by formula (1), a second diphenyl sulfone compound represented by formula (2), and both of the first diphenyl sulfone compound and the second diphenyl sulfone compound and wherein the total amount of the first diphenyl sulfone compound represented by formula (1) and the second diphenyl sulfone compound represented by formula (2) is 0.5 parts by mass to 3 parts by mass per 100 parts by mass of 4-hydroxy-4′-allyloxydiphenyl sulfone as to amounts of developers contained in the heat-sensitive color developing layer.