| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a DRAW type optical disk substrate which is formed by using a transesterification process polycarbonate, is little in the warpage of the substrate, small in the birefringence of the substrate, free of bright defects and free of defects in dye coating application, and method of manufacturing the DRAW type optical disk substrate. SOLUTION: This method of manufacturing the DRAW type optical disk substrate is constituted by forming a dye recording layer by application of dye onto the molded substrate obtained by injection molding the polycarbonate resin of 10,000 to 23,000 in viscosity average molecular weight manufactured by the transesterification process from an aromatic hydroxyl compound and diester carbonate and forming grooves on its signal surface, is characterized in that the contact angle of water drops measured by the signal surface before the formation of the dyestuff recording layer is 77 to 85 deg. and ionizing air of a positive polarity is blown in the direction parallel to the substrate surface. |
