| 摘要 |
<p>Provided are: crystallized glass which is provided with various physical properties that are required for applications as next-generation information recording media, while having extremely low specific gravity; and a crystallized glass substrate for information recording media. This crystallized glass contains, as a crystal phase, RAl2O4 and/or R2TiO4 (wherein R represents at least one element selected from among Zn, Mg and Fe), while containing, in mass% based on oxides, 40-60% of SiO2, 7-23% of Al2O3, 1-15% of TiO2, 1-20% of MgO, 0-10% of CaO, 0-5% of SrO, 0-5% of BaO, 0-15% of ZnO, 0-8% of FeO, 0-7% of P2O5, and 0% or more but less than 8% of B2O3, with the value of (MgO + CaO + SrO + BaO + ZnO + FeO)/(SiO2 + Al2O3) being 0.25 or less and the value of (ZnO + FeO)/MgO being 0-0.9 (inclusive). In addition, this crystallized glass has a specific gravity of 2.67 or less.</p> |
