| 摘要 |
PURPOSE:To enhance ground color stability to heat and solvent by a method wherein a urea compound having a group represented by a specified formula in the molecule as a developer is included in a heat-sensitive color developing layer, which contains a dye precursor and the developer for preparing the heat- sensitive recording body concerned. CONSTITUTION:In a heat-sensitive recording body having a heat-sensitive color developing layer containing a colorless or light-colored dye precursor and a developer, which develops color in the dye precursor by being reacted with the dye precursor under heat, a urea compound having a 3-pyridylurea group or 4-pyridylurea group represented by the formula I or the formula II in the molecule is included in the heat-sensitive color developing layer as the developer. In the formulae, X represents a 1-6C alkyl group, halogen atom or hydrogen atom. Thus, the use of the heat-sensitive recording body made possible under the temperature condition of 90-150 deg.C, under which conventional heat-sensitive recording body can not be used. Further, since no discoloration develops at the writing down with oily ink, the writing down with a writing apparatus on the heat-sensitive recording body can be possible with no limitation. |
