| abstract |
Heat-sensitive recording sheet comprising in a heat-sensitive color forming layer a colorless basic dyestuff and 4-isopropoxy-4'-hydroxydiphenyl sulfone as organic developer, wherein said color forming layer contains as sensitizer one of the compounds represented by the following formula (II) or (III): <IMAGE> (II) <IMAGE> (III) where, in the general formula (II) and (III), A represents a hydrogen atom, halogen atom, nitro group, lower alkyl group, lower alkoxy group or hydroxy group, l represents an integer from 1 to 5 and m represents an integer from 0 to 3. The sheet provides high density images and excellent stability of images. |