| 摘要 |
<p>Provided is a glass substrate for information recording media, which has improved strength, while having less read errors. A glass substrate for information recording media, which has main surfaces (1A, 1B) and a thickness of 0.630 mm or less. The maximum potassium ion exchange ratio thereof is from 20% to 50% (inclusive), and the potassium ion exchange ratios at a depth of 6μm from the main surfaces (1A, 1B) are from 20% to 40% (inclusive).</p> |
