| 摘要 |
PURPOSE:To allow the title recording medium to withstand long-term use by using a naphthalocyanine dye as the laser beam absorber as a heat energy generation source becoming the driving force of thermal expansion and mechanical deformation contained in an amorphous polymer layer. CONSTITUTION:A data recording medium formed by laminating the first elastic amorphous polymer layer and the second amorphous polymer layer having a glass transition point different in thermal expansion properties to a substrate is used to thermally expand the elastic amorphous polymer layer by data writing laser beam and the expanded state thereof is held by the second amorphous polymer layer to perform the writing of data. Further, the second amorphous polymer layer holding the expanded state of the first layer is heated to its glass transition point or higher by data erasing laser beam to return the first layer to the state before expansion to erase the data. As an absorber capable of selectively absorbing writing laser beam becoming a data erasing heat energy source and data erasing laser, a naphthalocyanine dye represented by formula [I] being an org. compound having high chemical and physical stability and extremely narrow absorbing band width is used. By this method, an inexpensive data rewritable optical recording medium capable of withstanding long-term use is obtained. |
