Glass substrate for information recording medium and magnetic recording medium having the substrate
US6187441A · kind A · utility
50Cited by
1References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1997 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Dec 24, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/315
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A glass substrate contains at least ZrO.sub.2 and Li.sub.2 O. In this event, ZrO.sub.2 has a content which falls within the range between 0.6 and 1.9 mol % while Li.sub.2 O has a content which falls within the range between 6 and 14 mol %. Thus, the contents of ZrO.sub.2 and Li.sub.2 O are restricted to a predetermined range. Consequently, the projections of the undissolved substance of ZrO.sub.2 are not formed on the surface of the glass substrate. As a result, the glass substrate having the flat surface can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.