Patent ID: 6642161
Filing Date: 2003-11-04
Classification: C03C

Abstract:
A polished glass ceramic disk medium substrate comprising crystalline and amorphous phases formed of a mixture of glass forming raw materials comprisingabout 35% to less than about 50% by weight of SiO2; about 5% to less than about 20% by weight of Al2O3; about 9% to less than about 25% by weight of MgO; about 0.1% to less than about 12% by weight of TiO2; and about 5% to less than about 10% by weight ZnO; wherein said glass disk medium substrate includes one or more crystalline phases selected from clinoenstatite, magnesium aluminum silicate, Zn2Ti3O8, Zn2TiO4, or a main crystalline phase of clinoenstatite and a secondary crystalline phase of enstatite.