| 摘要 |
PURPOSE:To impart a stable black color forming property and to make it possible to obtain long-term storage stability without generating pre-coupling, by providing a thermal recording layer containing a diazonium compound, a coupler compound represented by formula [I] and a heat-fusible basic compound to a support. CONSTITUTION:A coupler compound represented by formula I (wherein R1 and R2 are respectively hydrogen atom, a halogen atom, an alkoxy group and an alkyl group which may be substituted by halogen) is compounded with a diazonium compound in an amount of about 0.1-10pts.wt. thereof and synthesized by using a 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid and nitroaniline derivative as stock materials. If an amizine derivative is used as a heat-fusible basic compound used in order to react the diazonium compound and the coupler compound, a recording medium excellent in a color forming property and storage stability is obtained. Said basic compound is compounded in an amount of 1-30pts.wt. of the diazonium compound and a thermal recording layer is formed by applying a coating solution containing these substances to a support. |
