A heat-sensitive recording material.

摘要

A heat-sensitive recording material comprises a heat-sensitive color forming layer which is formed on a supporter and contains a colorless or light color leuco dyestuff as a color forming substance, a developer which develops color of the leuco dyestuff by reaction with it when heated and a sensitizer. The developer is 2,4'-dihydroxydiphenylsulfone having purity of 97 weight % or more and prepared by washing and drying crystal which is obtained by dissolving crude 2,4'-dihydroxydiphenylsulfone in an alcohol having 1 to 4 carbon atoms or in a mixture of an alcohol having 1 to 4 carbon atoms and water by heating and then cooling the solution or partially removing the solvent from the solution by distillation. The heat-sensitive recording material has excellent properties, such as reduced fog and excellent image preservation (weatherability).