Glass substrate for magnetic recording media and manufacturing method thereof
US6808784B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 2002 |
| Grant date | Oct 26, 2004 |
| Priority date | — |
| Expiry date | May 24, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/219
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
There is provided a glass substrate for magnetic recording media, which enables damage to a magnetic recording medium using the glass substrate to be prevented. The glass substrate is a donut-shaped glass substrate comprising major surfaces, an outer peripheral edge surface, an inner peripheral edge surface, and chamfered surfaces, each connecting between one of the major surfaces and one of the outer peripheral edge surface and the inner peripheral edge surface. Each of the chamfered surfaces comprises a conical surface part and an annular curved surface part connected to one another, and for each of the chamfered surfaces, a percentage ratio of a length of an outline of the annular curved surface part to a length of an outline of the chamfered surface in a cross section of the glass substrate including a central axis of the glass substrate is not less than a predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.