| 摘要 |
To provide glass for an information recording medium substrate, which is excellent in the acid resistance and weather resistance. Glass for an information recording medium substrate, which comprises, as represented by mol % based on the following oxides, from 61 to 72% of SiO2, from 3 to 12% of Al2O3, from 0 to 14.3 of Li2O, from 0 to 22% of Na2O, from 0 to 22% of K2O, from 4 to 13% of MgO, from 0 to 6% of TiO2 and from 0 to 5% of ZrO2, provided that the total content of Li2O, Na2O and K2O (R2O) is from 8 to 22%, the ratio of the content of Li2O to R2O (Li2O/R2O) is at most 0.52, the ratio of the content of Na2O to R2O (Na2O/R2O) is at least 0.35, or the ratio of the content of K2O to R2O (K2O/R2O) is at least 0.45.
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