| 摘要 |
PROBLEM TO BE SOLVED: To provide a crystallized glass and a crystallized glass substrate for an information recording medium having various physical properties required as applications for a next-generation information recording medium substrate and an extremely low specific gravity.SOLUTION: There is provided a crystallized glass which contains one or more selected from RAlOand RTiO(provided that R is one or more selected from Mg and Fe) as a crystalline phase. The crystallized glass contains 50 to 70% of SiO, 10% to 26% of AlO, 1 to 15% of TiO, 2.5 to 25% of MgO, 0 to 8% of FeO and 0 to less than 2% of ZnO in terms of mass% of oxide. The value of (AlO+MgO)/SiOis 0.30 or more and 0.65 or less and the specific gravity is 2.63 or less. |
