Process for producing glass substrate for information recording medium and process for producing recording medium using said glass substrate
US6430965B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 2001 |
| Grant date | Aug 13, 2002 |
| Priority date | — |
| Expiry date | Jun 14, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/8404
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing a glass substrate for an information recording medium comprising: (a) polishing a principal surface of a glass substrate to provide a polished glass substrate; (b) washing the polished glass substrate with a washing agent; (c) chemically strengthening the glass substrate by immersing the glass substrate in a chemical reinforcement liquid to exchange ions on a surface layer of the glass substrate with ions in the chemical reinforcement liquid having a diameter larger than the ions in the glass substrate; (d) cleaning the surface of the glass substrate with a cleaning agent; (e) drying the surface of the glass substrate; (f) inspecting the surface of the glass substrate; and (g) packing the glass substrate or storing the glass substrate in a container; wherein at least one of the steps (b), (c), (d), (e), (f) and (g) is performed in an atmosphere in which clean filtered air is circulated to prevent particles from being adhered on the surface of the glass substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.