Patent ID: 8652659

Claim:
A glass substrate for an information recording medium made of aluminosilicate glass containing 60% to 75% by mass of SiO 2 , 5% to 18% by mass of Al 2 O 3 , 3% to 10% by mass of Li 2 O, 3% to 15% by mass of Na 2 O, and 0.5% to 8% by mass of ZrO 2 with respect to whole glass components, and containing neither As (arsenic) element nor Sb (antimony) element, comprising: a fining agent containing SO 3 (sulfurous acid), wherein a molar ratio of a whole amount of the fining agent to the Al 2 O 3 , which is (the whole amount of the fining agent)/Al 2 O 3 , is within a range of 0.02 to 0.20; and wherein a total content of the fining agent is in a range of 1% by mass or less with respect to the whole glass components.