| 摘要 |
PURPOSE:To prevent the damage and to hold a print characteristic and to obtain an optical disc of less warp by forming a cross-linkable high polymer hardened thin film on the upper face of a resin substrate on the die opposite to a metallic thin film face and specifying the thickness of this hardened thin film for the thickness of a high polymer film which protects metals. CONSTITUTION:A metallic thin film 2 is formed on a rugged signal of an injection-molded resin substrate 1 by sputtering, and a metal protecting high polymer film 4 having a thickness (d) is formed on the thin film 2, and various kinds of print are provided on the film 4, and a cross-linkable high polymer hardened thin film 5 is formed on the reading side of the signal of the resin substrate. With respect to this cross-linkable high polymer hardened thin film 5, acrylic coating materials or silicone coating materials which are hardened with ultraviolet rays are used, and its thickness (t) is set to satisfy 1/10<=t/d<=4/5. Thus, the print characteristic on the rear face is held, and a damage preventing film is formed, and the optical disc of less warp is obtained. |
