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US4536443A
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Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1983-09-26
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Granted: 1985-08-20
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Expires: 2003-09-26
Abstract
Abstract A magnetic recording medium comprises a non-magnetic substrate and at least one layer of obliquely deposited magnetic crystals which contains, as a main constituent, Co or a Co--Ni based alloy containing Cr in an amount within the range of 2 to 8 atom % and has a density of 5.0 g/cm 3 or more, said layer being formed on said non-magnetic substrate.
Inventors
- 👤 Makoto Nagao
- 👤 Akira Nahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:49
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/225; C23C14/226; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
67 words
A magnetic recording medium comprising a non-magnetic substrate and at least one layer of obliquely deposited magnetic crystals having a curved columnar structure which contains, as a main constituent, Co or a Co--Ni based alloy containing Cr in an amount within the range of 2 to 8 atom % and has a density of 5.0 g/cm 3 or more, said layer being formed on said non-magnetic substrate.
Claim 2
Dependent Claim
67 words
A magnetic recording medium comprising a non-magnetic substrate and at least one layer of obliquely deposited magnetic crystals having a curved columnar structure which contains, as a main constituent, Co or a Co--Ni based alloy containing Cr in an amount within the range of 2 to 8 atom % and has a density of 5.0 g/cm 3 or more, said layer being formed on said non-magnetic substrate.
Claim 3
Dependent Claim
28 words
A magnetic recording medium as defined in claim 1 wherein said Co--Ni based alloy contains Ni in an amount within the range of 0 to 25 atom %.
Claim 4
Dependent Claim
24 words
A magnetic recording medium as defined in claim 1 wherein the thickness of said layer is within the range of 500 Å to 5,000Å.
Claim 5
Dependent Claim
19 words
A magnetic recording medium as defined in claim 1 wherein said non-magnetic substrate is made of a high-molecular material.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-19 | 1989-02-18 | 1989-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-19 | 1993-02-18 | 1993-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-19 | 1997-02-18 | 1997-08-20 | $7700.00 | Window Closed / Lapsed |