4-HYDROXY-4'-ISOPROPOXYDIPHENYL SULFONE COLOR DEVELOPING COMPOSITION, METHOD FOR WET GRINDING AND FLUID DISPERSION

摘要

PROBLEM TO BE SOLVED: To provide a means for preventing 4-hydroxy-4'-isopropoxydiphenyl sulfone being a color developing agent used for a recording paper such as a thermal recording paper from being hydrated. SOLUTION: 4-Hydroxy-4'-isopropoxydiphenyl sulfone is wet-ground or dispersed in the presence of 0.05-5 pts.wt. of one or at least two kinds of compounds selected from diphenyl sulfone derivatives of general formula (I) to 100 pts.wt. of 4-hydroxy-4'-isopropoxydiphenyl sulfone. (In the formula, R<1> is a hydrogen atom or a lower alkyl group and R<2> and R<3> are each independently a lower alkyl group and n and m are each 0 or an integer of 1 to 4).