Patent EP0103362A2 successfully refreshed from Google Patents.
Patent US4868070A successfully refreshed from Google Patents.
US4868070A
Expired / Lapsed
US
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Vertical magnetization type recording medium and manufacturing method therefor
Assignee: Fujifilm Holdings Corp
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Filing: 1987-06-10
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Granted: 1989-09-19
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Expires: 2007-06-10
Abstract
Abstract In a method of manufacturing a vertical magnetization type recording medium, a soft magnetic film layer is formed on each of the two sides of a non-magnetic support, and then a vertical magnetization film layer is formed on each soft magnetic film layer thus formed, thereby to provide a vertical magnetization type recording medium which has both sides uniform in characteristics and has characteristics making it excellent as a vertical magnetization type recording medium.
Inventors
- 👤 Makoto Nagao
- 👤 Fusao Yamanaka
- 👤 Akira Nahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:18
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/851; G11B5/62; G11B5/64; G11B5/66; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10S428/922; Y10S428/9265; Y10S428/928; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/12771; Y10T428/12861; Y10T428/12937; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/269
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
117 words
A vertical magnetization type recording medium comprising a nonmagnetic support made of polyethyleneterphthalate or polyimide, a soft magnetic layer comprising Fe-Al-Si or Fe-Ni-Mo-Cu formed on each of two sides of said support, and a vertical magnetization film layer comprising an alloy material essentially containing Co and Cr formed on each of said soft magnetic layers, said vertical magnetization film layers and soft magnetic film layers being formed by the process comprising the steps of: forming a soft magnetic film layer on each of said two sides of said support by high speed continuous sputtering; and then forming a vertical magnetization film layer by high speed continuous sputtering on each of the soft magnetic film layers thus formed.
Claim 2
Dependent Claim
117 words
A vertical magnetization type recording medium comprising a nonmagnetic support made of polyethyleneterphthalate or polyimide, a soft magnetic layer comprising Fe-Al-Si or Fe-Ni-Mo-Cu formed on each of two sides of said support, and a vertical magnetization film layer comprising an alloy material essentially containing Co and Cr formed on each of said soft magnetic layers, said vertical magnetization film layers and soft magnetic film layers being formed by the process comprising the steps of: forming a soft magnetic film layer on each of said two sides of said support by high speed continuous sputtering; and then forming a vertical magnetization film layer by high speed continuous sputtering on each of the soft magnetic film layers thus formed.
Claim 3
Dependent Claim
45 words
The recording medium of claim 1, wherein said soft magnetic film layers are formed by sputtering using soft magnetic film sources provided around cylindrical cans, and said vertical magnetization film layers are formed by sputtering using vertical magnetization film sources provided around said cylindrical cans.
Claim 4
Dependent Claim
43 words
The recording medium as claimed in claim 1, wherein said soft magnetic film layers are formed at a temperature in a range of 30° to 90° C., and said vertical magnetization film layers are formed at a temperature of at least 90° C.
Claim 5
Dependent Claim
27 words
The recording medium as claimed in claim 3, where said soft magnetic film layers are formed at a temperature in a range of 45° to 65° C.
Claim 6
Dependent Claim
24 words
The recording medium as claimed in claim 3, wherein said vertical magnetization film layers are formed at a temperature of at least 120° C.
Claim 7
Dependent Claim
28 words
The recording medium as claimed in claim 3, wherein said support is treated in advance by a process for decreasing the discharge of impurity gas from said support.
Claim 8
Dependent Claim
26 words
The recording medium as claimed in claim 1, wherein a thickness of said soft magnetic film layers is in a range of 0.03 to 5 microns.
Claim 9
Dependent Claim
26 words
The recording medium as claimed in claim 1, wherein a thickness of said soft magnetic film layers is in a range of 0.1 to 1 micron.
Claim 10
Dependent Claim
28 words
The recording medium as claimed in claim 1, wherein an easy magnetizing axis of said vertical magnetization film layers is oriented perpendicular to a surface of said support.
Claim 11
Dependent Claim
26 words
The recording medium as claimed in claim 1, wherein a thickness of said vertical magnetization film layers is in a range of 0.03 to 5 microns.
Claim 12
Dependent Claim
26 words
The recording medium as claimed in claim 1, wherein a thickness of said vertical magnetization film layers is in a range of 0.05 to 1 micron.
Claim 13
Dependent Claim
30 words
The recording medium as claimed in claim 1, wherein said recording medium further comprises a base layer, an intermediate layer, and an overcoat layer on each side of said support.
References Cited (Backward Citations)
US4277809A
Cited
JPS56169220A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-18 | 1993-03-20 | 1993-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-18 | 1997-03-20 | 1997-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-18 | 2001-03-20 | 2001-09-19 | $7700.00 | Window Closed / Lapsed |