Patent ID: 7706240
Filing Date: 2010-04-27
Classification: G11B

Abstract:
1. An optical disk, comprising: a substrate including resin-impregnated paper in which a resin has been impregnated into paper or resin-coated paper in which paper surface has been coated with a resin; wherein a centerline average roughness Ra of at least one side of the substrate is 0.5 μm or less, and a maximum roughness Rmax is 6.0 μm or less; a recording layer provided on at least one side of the substrate wherein the recording layer has a recording layer base material that serves as a support for the recording layer, and the recording layer base material includes a non-hydrophilic film; a printing layer provided on at least one side of the substrate, having a printing base material and a printed ink applied to a surface of the printing base material facing the substrate; and at least one release layer provided between the substrate and the recording layer and/or between the substrate and the printing layer, wherein the substrate has peripheral edges protected by resin coating or by attaching a resin cover and/or by being shaped into a curve.