PURPOSE: To obtain the titled optical disk having high recording sensitivity, density, and reliability by using the material obtained by curing an UV curing resin composition consisting of a specified compd. and a photopolymerization initiator as a substrate layer.
CONSTITUTION: The substrate layer having reggedness corresponding to the information signal and a recording film layer are successively formed on a transparent substrate to obtain the optical disk. An UV curing resin composition is obtained by mixing 100pts.wt. mixture consisting of 50W100pts.wt. compd. shown by the general formula (1) and 50W0pts.wt. compd. shown by the general formula (2) and 0.1W5.0pts.wt., based on 100pts.wt. mixture, photopolymerization initiator. The composition is cured, and the cured material is used in the sub strate layer. When ≤50pts.wt. compd. shown by the general formula (1) is mixed, the releasability from a stamper and the resistance of the cured material to moisture and heat are deteriorated, the molding strain is increased, and the mechanical strength is decreased.
MIWA HIROAKI
SUDO RYOICHI
HITACHI MAXELL