| 摘要 |
PURPOSE:To prepare a thermal recording material of multivalued quality having high whiteness and excellent recording sensitivity with high efficiency, in dispersing a dye precursor dispersion containing an electron donating dye precursor using dispersing media having a specific diameter or less, by adjusting the temp. of a dispersion at the discharge port of a dispersing machine to a specific value. CONSTITUTION:A coating solution for thermal recording containing a dye dispersion containing a colorless electron donating dye precursor and a developer dispersion containing an electron acceptive developing compound reacting with the dye precursor under heating to develop a color is applied to one surface of a sheet-like support and solidified to form a thermal recording layer. In this process, the dye precursor is dispersed using dispersing media having a diameter of 0.9mm or less while the temp. of the dispersion at the discharge port of a dispersing machine is adjusted to 30-60 deg.C. When the liquid temp. at the discharge port of the dispersing machine is lower than 30 deg.C, the whiteness of the dispersion becomes insufficient and, when said temp. becomes higher than 60 deg.C, no practical effect is obtained because reflocculation of dispersed particles and a marked increase in viscosity are generated. |
