| 摘要 |
PROBLEM TO BE SOLVED: To improve production efficiency and to reduce a production cost while maintaining the mechanical characteristics and recording and reproducing characteristics of an optical disk by constituting a second substrate of a resin having the viscosity average mol.wt. and dust quantity larger than specific values. SOLUTION: A first substrate 1 having 0.6mm thickness is manufactured by injection molding optical grade polycarbonate (PC). Rugged patterns meeting to information signals are formed on one main surface of the substrate 1. An A; reflection layer having 520nm film thickness is formed by an RR sputtering method on such substrate 1. A UV curing resin is applied on the Al reflection layer and is irradiated with UV rays, by which a protective layer 3 having 15μm thickness is formed. On the other head, the second substrate 5 having 0.6mm thickness is formed by extrusion molding of a PC resin. The UV curing adhesive is further applied on the protective layer of the first substrate 1 at 10μm thickness. The second substrate 5 is stick to the substrate and is irradiated with UV rays to cure the adhesive by which the laminated disk is manufactured. |
