THERMAL RECORDING MATERIAL

摘要

This invention relates to a thermal recording material with outstanding color-developing sensitivity and storage stability of images. The thermal recording material comprising a support and a thermosensitive color-developing layer provided thereon comprising a leuco dye which is colorless or light-colored at normal temperature, an organic acid substance which reacts upon heating with the leuco dye to develop color and a sensitizer. Said thermosensitive color-developing layer comprises at least one kind of diphenyl sulfone derivative selected from 4-hydroxydiphenyl sulfone derivatives represented by the following general formula (1) or general formula (2), 4,4'-dihydroxydiphenyl sulfone and 2,4'-dihydroxydiphenyl sulfone as an organic acid substance and a 4-acylbiphenyl as a sensitizer. (wherein R1 is an alkyl, aralkyl or aryl group) (wherein Y is a divalent organic group and n is an integer in the range 0-6)