Optical information recording medium.

摘要

The present invention provides an optical information recording medium of the type which comprises a substrate and a recording layer formed on the substrate, the substrate comprising an injection molded piece of a polycarbonate resin composition having a releasing agent content of 0.005 to 0.5 % by weight of a fatty acid ester having a hydroxyl value of not greater than 5 mg of KOH/g and a thermal stabilizer content of not greater than 5 ppm. When the polycarbonate resin or its composition is injection molded, the resin temperature is defined in a certain range, by which hydrolysis of the polycarbonate resin can be prevented. Thus, the medium has a reduced number of defects and long-term reliability.