METHOD FOR MANUFACTURING GLASS SUBSTRATE FOR INFORMATION RECORDING MEDIUM

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PROBLEM TO BE SOLVED : To provide a method for manufacturing a glass substrate for an information recording medium which can obtain a glass substrate for an information recording medium having satisfactory smoothness and flatness even in the case where polishing is performed after chemical strengthening. SOLUTION : The method for producing a glass substrate for an information recording medium is performed using, as a glass blank, the one made of a glass stock comprising the alkaline-earth metal of MgO and CaO and the alkali metal of Li2O, Na2O and K2O, and in which the mass ratio of the alkali metal to the alkaline-earth metal lies in the range of 0.1<(MgO+CaO)/(Li2O+Na2O+K2O)<0.80 to obtain a disk-shaped glass substrate 1a for an information recording medium. COPYRIGHT : (C)2012, JPO&INPIT