US4557944A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of manufacturing a magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1985-01-18
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Granted: 1985-12-10
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Expires: 2005-01-18
Abstract
Abstract A nonbinder type of magnetic recording medium is disclosed. The binder is comprised of a non-magnetic support having thereon, in sequence, a thin magnetic metal film laminated using the evaporation technique and a protecting film, with the thin magnetic metal film converted in its surface part alone to a metal oxide layer by being oxidized with oxygen plasma, to a metal nitride layer by being nitrided with nitrogen plasma or to a glow discharge-processed layer. The protecting film includes a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof, laminated on the metal oxide layer, the metal nitride layer or the glow discharge-processed layer.
Inventors
- 👤 Yoshihiro Arai
- 👤 Akira Nahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:45
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; G11B5/64; G11B5/66; G11B5/672; G11B5/84; G11B5/851; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
103 words
A process for manufacturing a magnetic recording medium, comprising the sequential steps of: evaporating a thin film of a magnetic metal onto a non-magnetic support; converting the surface part of said thin film of the magnetic metal to the layer of the oxide by subjecting the thin film surface of the magnetic metal to an oxidizing processing with oxygen plasma generated by high voltage application; and forming, under a succeeded vacuum condition, on the converted surface part of the magnetic metal film a protecting film of a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof.
Claim 2
Dependent Claim
103 words
A process for manufacturing a magnetic recording medium, comprising the sequential steps of: evaporating a thin film of a magnetic metal onto a non-magnetic support; converting the surface part of said thin film of the magnetic metal to the layer of the oxide by subjecting the thin film surface of the magnetic metal to an oxidizing processing with oxygen plasma generated by high voltage application; and forming, under a succeeded vacuum condition, on the converted surface part of the magnetic metal film a protecting film of a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof.
Claim 3
Dependent Claim
105 words
A process for manufacturing a magnetic recording medium, comprising the sequential steps of: evaporating a thin film of a magnetic metal onto a non-magnetic support; converting the surface part of said thin film of the magnetic metal to a layer of nitride of the magnetic metal by subjecting the thin film surface of the magnetic metal to a nitriding processing with nitrogen plasma generated by high voltage application; and forming, under a vacuum condition, on the converted surface part of the magnetic metal film, a protecting film of a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof.
Claim 4
Dependent Claim
105 words
A process for manufacturing a magnetic recording medium, comprising the sequential steps of: evaporating a thin film of a magnetic metal onto a non-magnetic support; converting the surface part of said thin film of the magnetic metal to a layer of nitride of the magnetic metal by subjecting the thin film surface of the magnetic metal to a nitriding processing with nitrogen plasma generated by high voltage application; and forming, under a vacuum condition, on the converted surface part of the magnetic metal film, a protecting film of a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof.
Claim 5
Dependent Claim
97 words
A process for manufacturing a magnetic recording medium, comprising the sequential steps of: evaporating a thin film of a magnetic metal onto a non-magnetic support; converting the surface part of said thin film of the magnetic metal to a layer of the glow discharge-process layer by subjecting the thin film surface of the magnetic metal to a glow discharge processing; and forming under a vacuum condition, on the converted surface part of the magnetic metal film, a protecting film of a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof.
Claim 6
Dependent Claim
97 words
A process for manufacturing a magnetic recording medium, comprising the sequential steps of: evaporating a thin film of a magnetic metal onto a non-magnetic support; converting the surface part of said thin film of the magnetic metal to a layer of the glow discharge-process layer by subjecting the thin film surface of the magnetic metal to a glow discharge processing; and forming under a vacuum condition, on the converted surface part of the magnetic metal film, a protecting film of a high molecular weight compound, a higher fatty acid, a fatty acid ester or a combination thereof.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-09 | 1989-06-10 | 1989-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-09 | 1993-06-10 | 1993-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-09 | 1997-06-10 | 1997-12-10 | $7700.00 | Window Closed / Lapsed |