Patent US2844200A successfully refreshed from Google Patents.
Patent US4990362A successfully refreshed from Google Patents.
US4990362A
Expired / Lapsed
US
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Method of manufacturing a titanium magnetic disk substrate
Assignee: JFE Engineering Corp
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Filing: 1990-02-16
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Granted: 1991-02-05
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Expires: 2010-02-16
Abstract
Abstract Titanium magnetic disk substrates are manufactured by preparing a base by stripping not less than 5 μm from the surface layer of a titanium cold-rolled plate, and then forming a film of not less than 5 μm consisting of 1 or more non-magnetic transition metal elements belonging to Groups IVA, VA, VIA, VIIA and VIIIA of the Periodic Table, on the surface of this base.
Inventors
- 👤 Hiroshi Kibe
- 👤 Hideaki Fukai
- 👤 Hiroyoshi Suenaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:41
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/8404; G11B5/62; G11B5/73; G11B5/739; G11B5/73911; G11B5/73913; G11B5/73917; G11B5/73919
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
69 words
A method of manufacturing titanium magnetic disk substrates comprising steps of: preparing a base by removing not less than 5 μm from the surface layer of a titanium cold-rolled plate, and forming a film of not less than 5 μm consisting essentially of 1 or more non-magnetic transition metal elements belonging to Groups IVA, VA, VIA, VIIA and VIIIA of the Periodic Table, on the surface of the base.
Claim 2
Independent Claim
69 words
A method of manufacturing titanium magnetic disk substrates comprising steps of: preparing a base by removing not less than 5 μm from the surface layer of a titanium cold-rolled plate, and forming a film of not less than 5 μm consisting essentially of 1 or more non-magnetic transition metal elements belonging to Groups IVA, VA, VIA, VIIA and VIIIA of the Periodic Table, on the surface of the base.
Claim 3
Dependent Claim
25 words
A method of manufacturing titanium magnetic disk substrates according to claim 1, wherein said film is formed by ion plating, sputtering, vacuum deposition or CVD.
Claim 4
Dependent Claim
38 words
A method of manufacturing titanium magnetic disk substrates according to claim 1, wherein the removal of the surface layer of the titanium cold-rolled plate in said process for preparing a base is effected by pickling, cutting or grinding.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-04 | 1994-08-06 | 1995-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-04 | 1998-08-06 | 1999-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-04 | 2002-08-06 | 2003-02-05 | $7700.00 | Window Closed / Lapsed |