| 摘要 |
PURPOSE:To provide the title color which comprises an anthraquinone compd. of a specific formula and gives a recording medium excellent in writing characteristics and record storage properties such as heat resistance and light resistance. CONSTITUTION:The title color is represented by formula I (wherein each of benzene rings A, B, C, and D may be substd. by lower alkyl, cycloalkyl, lower alkoxy, trifluoromethyl, or halogen), and gives an optical recording medium excellent in writing characteristics and record storage properties such as heat resistance and light resistane. The color is prepd. e.g. by thermally reacting 1mol of leuco-1,4,5,8-tetrahydroxyanthraquinone with at least 4mol of at least one aniline deriv. selected from the group consisting of derivs. of formulas II, III, IV, and V in the absence or presence of a solvent in the presence of boric acid, a mineral acid, and zinc at 50-300 deg.C. |
