| 摘要 |
PROBLEM TO BE SOLVED: To provide the high sensitivity and superior water resistance and heat resistance and resistance to plasticizer of a white paper by using an aqueous dispersion liquid in which a leuco dye and 4,4'-diallyloxydiphenyl sulfone are covariance treated in a water medium so that the volume average particle diameter is a specified numerical value or under in a heat-sensitive coloring layer. SOLUTION: A heat-sensitive coloring layer is formed on one face of a substrate, on which a protective layer is formed. An aqueous dispersion liquid prepared by covariance treating a leuco dye and 4,4'-diallyloxydiphenyl sulfone is used for the heat-sensitive coloring layer. The volume average particle diameters of leuco dye and 4'-diallyloxydiphenyl sulfone are set as 2μm or less, preferably 1μm or less. The adding amount of 4,4'-diallyloxydiphenyl sulfone is 20-300wt.% to the leuco dye, and particularly it is desirable to add the amount in the range of 50-200wt.%. |
