摘要 |
A glass substrate for information recording medium, said glass substrate being composed of an alminosilicate glass containing 60-75% by mass of SiO2, 5-18% by mass of Al2O3, 3-10% by mass of Li2O, 3-15% by mass of Na2O and 0.5-8% by mass of ZrO2 relative to the entire glass components. The glass substrate for information recording medium contains neither As (arsenic) nor Sb (antimony), while containing at least one substance selected from the group consisting of SO3 (sulfurous acid), F (fluorine), Cl (chlorine), Br (bromine) and I (iodine), as a refining agent. The molar ratio of the total amount of the refining agent to the amount of ZrO2 is within the range of 0.05-0.50.
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