| 摘要 |
PURPOSE:To perform erasing and rewriting by laser light and to improve erasing efficiency, to reduce the deterioration of erasure and to improve an S/N by providing a recording layer consisting of a thermoplastic resin with low molecular weight and coloring materials at a proportion within a specific range on a substrate. CONSTITUTION:The optical recording layer obtained by incorporating the coloring materials in the thermoplastic resin with <=30,000 average molecular weight such as polyolefine, styrene (co)polymer, acrylic resin, polyamide, etc. at 2-100wt. ratio is formed on the surface of a (non)reflective substrate at 0.007-20mu thickness. It may be available that an intermediate layer made of a thermoplastic resin, thermosetting resin or resin curable by electron beam which has a heat insulating effect at the temperature rise of the recording layer and increases writing sensitivity especially, or an intermediate layer obtained by vapor-depositing SiO2, MgF2, etc. is formed between the optical recording layer and the substrate having 0.001-20mu thickness. Thus, writing is executed by the irradiation of laser light and rewriting is also attained after smoothing and erasing a bit formation part by the irradiation of heating or erasing light. Consequently, the recording medium having reduced deterioration in spite of repeated erasing and writing and the reduced SN variation caused by the output variation of recording light is obtained. |
