| 摘要 |
PURPOSE:To obtain a thermal recording material excellent in preservability of a ground and preservability of images by a method wherein a heat-sensitive coating liquid for forming a thermal recording layer of a thermal recording material is adjusted to have a pH in a predetermined range, before being applied to a support. CONSTITUTION:A heat-sensitive coating liquid for forming a thermal recording layer of a thermal recording material comprising an aromatic isocyanate compound and an imino compound for forming a color by reacting with the isocyanate compound when being heated, on a support, is adjusted to have a pH of 5-12. The pH adjustment is carried out by use of an acidic compound and a basic compound. Acetic acid, acrylic acid or the like may be used as an organic acidic substance, whereas sulfuric acid, hydrochloric acid or the like may be used as an inorganic acidic substance. Sodium hydroxide, potassium hydroxide or the like may be used as an organic basic substance, whereas trisodium phosphate or the like may be used as an inorganic basic substance. The aromatic isocyanate compound may be 2,6-dichlorophenyl isocyanate or the like, and the imino compound may be 3-iminoisoindolin-1-one or the like. |
