Patent ID: 9053734
Filing Date: 2015-06-09
Classification: C03C,G11B

Abstract:
1. A glass substrate for information recording media, comprising, with respect to all components of the glass substrate: 45% to 75% by mass of SiO 1% to 20% by mass of Al 0% to 8% by mass of B wherein a total amount of the SiO R 2 O, a total amount of which being 7% to 20% by mass where: R represents Li, Na, or K; R′O, a total amount of which being 0.1% to 12% by mass where: R′ represents Mg, Ca, Sr, Ba, and Zn; TiO wherein the glass substrate for information recording media comprises at least one polyvalent element selected from a group consisting of V, Mn, Ni, Mo, Sn, Ce, and Bi, and wherein a mole ratio, which is (a total amount of an oxide of the polyvalent element)/(a total amount of the TiO