| 摘要 |
PURPOSE:To prevent the deformation of a disk with age by adhering a nonmagnetic metallic plate which is thin and strong to a disk substrate. CONSTITUTION:A recording layer 10 consisting successively of an underlying layer, magnetic layer formed with a ternary alloy film composed of Cd (cadmium), Tb (terbium) and Fe (iron) by sputtering and protective film layer is formed on the base of the hollow groove 8 of he acrylic substrate 2. A stainless steel plate 7 which is a nonmagnetic metal is adhered onto the layer 10 via a hollow part (air layer) 9 as an intermediate layer having low heat conductivity to constitute the above-mentioned medium. The deformation of the substrate with age is thus prevented even if the acrylic substrate which is a plastic substrate is used. The diffusion of heat in the stage of recording is prevented and the energy loss is prevented as well. |
