Coating solution for heat-sensitive color-developing layer, and heat-sensitive recording material

摘要

Provided are a coating solution for a thermosensitive color developing layer of excellent storability wherein color development during its storage or during producing a thermal recording material is suppressed, and a thermal recording material with excellent print portion (image portion) storability and suppressed staining in the background color (white background). A coating solution for a thermosensitive color developing layer, which comprises a colorless or pale-colored electron-donating leuco dye, a hindered phenol compound and, as an electron-accepting developer, a diphenylsulfone derivative represented by the following formula (1): wherein the aforementioned hindered phenol compound has an average particle size (D50) of not more than 0.5 mum, and the coating solution has a color tone a* of not less than -4.0 as measured according to JIS Z 8729 and a whiteness W of not less than 62 as measured according to JIS Z 8715.