| 摘要 |
PURPOSE:To obtain a color-forming recording material forming a pure black with a large absorption in a near infrared part and a superior image shelf stability by a method wherein the recording material contains a leuco dye and a color developer as main components, and the leuco dye is made of compounds shown by specific formulas. CONSTITUTION:A color-forming recording material contains a leuco dye and a color developer as main components. The leuco dye is made of a compound shown by a formula (I and at least one of compounds shown by formulas (II), (III), and (IV). In the formula, R<1> and R<2> represent lower alkyl group, or R<1> and R<2> may be bonded to produce a pyrrolidine ring or a piperidine ring together with an adjacent N atom; X represents the same or different kinds of substituents selected out of a lower alkyl group and a halogen atom group; and (n) represents 1 or 2. In the aforesaid dye compound, the compound (II), (III), or (IV) is mixed in a ratio of 15-5 pts.wt. and the compound shown by the formula (I) is mixed in a ratio of 85-95 pts.wt. |
