To provide a method for manufacturing particulate dispersions excellent in safekeeping/storage stability by making a material for a thermal recording body micronized by a process of using no sand grinder, and further the thermal recording body having high sensitivity and being substantially free from a ground stain and excellent in shelf stability of a recorded image.

In this manufacturing method of the particulate dispersions of the material for the thermal recording body, a single dye precursor, developer or sensitizer (hereinafter sometimes called simply as "material for thermal recording material") (except the case of the single sensitizer) or a mixture thereof (except the mixture of dye precursor and developer and that of dye precursor, developer and sensitizer) and emulsified dispersant water are mixed together, and the material for the thermal recording material is emulsified in a molten state and made micronized. Then, the micronized dispersions are crystallized by quenching.