| 摘要 |
PURPOSE:To obtain an optical disk substrate, by molding a resin consisting of an aromatic polyester and polyolefin and exposing the molded resin to radiation and improved heat resistance as well as transparency and small birefringence. CONSTITUTION:An optical disk substrate produced by kneading (A) 70-95wt%, preferably 80-90wt% aromatic polyester with (B) 5-30wt%, preferably 10-20wt% low-molecular weight polyolefin having 1,000-10,000, preferably 2,000-5,000mol.wt. while heating, pelletizing the kneaded blend, molding the resultant pellets with an injection molding machine, heating the molded article, preferably in a vacuum at about the melting point of the polyolefin (B), exposing the article to radiation, e.g. at 90-110 deg.C in an atmosphere under 2X10<-4>-5X10<-6>Torr vacuum degree, and irradiating the heated article with electron rays at 20-70Mrad using an electron accelerator. |
