COLOR DEVELOPER AND THERMAL RECORDING MATERIAL CONTAINING THE SAME

摘要

A thermal recording material which is obtained by dispersing in a dispersion medium a color-forming dye and a color developer which comprises 2,4'-dihydroxydiphenyl sulfone as the main ingredient and in which the proportion of 2,4'-dihydroxydiphenyl sulfone to 4,4'-dihydroxydiphenyl sulfone is from 90/10 to 100/0, excluding 90/10, by weight and the content of phenyl phenolsulfonate is 1.5 wt.% or lower based on the sum of those two compounds to thereby prepare a dispersion, applying the dispersion to a substrate, and drying it. The thermal recording material hence comprises the substrate and formed thereon a heat-sensitive color-developing layer comprising the color developer and color-forming dye. This recording material is reduced in background fogging and excellent in storage stability. The color developer is suitable for use in the thermal recording material.