| 摘要 |
PURPOSE:To execute recording, erasing and reproducing with light exclusive of UV rays by using a recording layer contg. a benzoindoline spiropyrane compd., a phenolic compd. and a dyestuff having the absorption region exclusive of the absorption region of the benzoindoline spiropyrane compd. CONSTITUTION:The recording medium is formed by successively forming a light reflecting layer 2, a recording layer 3 and a protective layer 4 on a substrate 1. The recording layer 3 is formed by incorporating the benzoindoline spiropyrane compd., the phenolic compd. and the dyestuff having the absorption region exclusive of the absorption region of the benzoindoline spiropyrane compd. therein and is further formed by incorporating a high-polymer material therein. This recording medium is subjected to writing of information by the light of the wavelength of the absorption region of the colored benzoindoline spiropyrane compd. from the recording layer 3 side and is subjected to erasing by the light of the absorption region exclusive of the absorption region of the benzoindoline spiropyrane compd. Reproducing is executed by the light of the intensity weaker than the intensity of the writing light. |
