US4865878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing vertical magnetization type recording medium
Assignee: Fujifilm Corp
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Filing: 1988-06-07
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Granted: 1989-09-12
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Expires: 2008-06-07
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. This is a division of application Ser. No. 59,242 filed 6/10/87, which is a continuation of application Ser. No. 802,150 filed 11/27/85 both are now abandoned.
Inventors
- 👤 Makoto Nagao
- 👤 Fusao Yamanaka
- 👤 Akira Nahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:52
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: 17
Claim 1
Independent Claim
99 words
A method for manufacturing a vertical magnetization type recording medium in which a magnetic recording layer consisting of a soft magnetic film layer and a vertical magnetization film layer is formed on each of two sides of a nonmagnetic support by sputtering or vacuum deposition while said support is being run, comprising the steps of: forming a soft magnetic film layer on each of said two sides of said support by sputtering or vacuum deposition; and then forming a vertical magnetization film layer by sputtering or vacuum deposition on each of the two soft magnetic film layers thus formed.
Claim 2
Independent Claim
99 words
A method for manufacturing a vertical magnetization type recording medium in which a magnetic recording layer consisting of a soft magnetic film layer and a vertical magnetization film layer is formed on each of two sides of a nonmagnetic support by sputtering or vacuum deposition while said support is being run, comprising the steps of: forming a soft magnetic film layer on each of said two sides of said support by sputtering or vacuum deposition; and then forming a vertical magnetization film layer by sputtering or vacuum deposition on each of the two soft magnetic film layers thus formed.
Claim 3
Dependent Claim
61 words
The method as claimed in claim 1 wherein the step of forming said soft magnetic film layers is carried out by sputtering or vacuum deposition using soft magnetic film sources provided around cylindrical cans; and the step of forming said vertical magnetization films is carried out by sputtering or vacuum deposition using vertical magnetization film sources provided around said cylindrical cans.
Claim 4
Dependent Claim
42 words
The method 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
26 words
The method as claimed in claim 3, wherein said soft magnetic film layers are formed at a temperature in a range of 45 to 65° C.
Claim 6
Dependent Claim
23 words
The method 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
29 words
The method as claimed in claim 3, wherein said support is made of a macromolecular material selected from the group consisting of polyethyleneterephthalate, polyimide, polyamide, polyphenylesulfide, polyethersulfone, and polysulfone.
Claim 8
Dependent Claim
30 words
The method as claimed in claim 6, further comprising the step of treating said support in advance by a process for decreasing the discharge of impurity gas from said support.
Claim 9
Dependent Claim
29 words
The method as claimed in claim 1, wherein said soft magnetic film layers are made of a permalloy material selected from the group consisting of Ni-Fe Ni-Fe-Mo, and Ni-Fe-Mo-Cu.
Claim 10
Dependent Claim
43 words
The method as claimed in claim 1, wherein said soft magnetic film layers are made of a soft alloy selected from the group consisting of Fe, Fe-Al-Si, Fe-Ni-O, Fe-Ti, Ni-Fe-Cn-Cr-Mn, Fe-Si-B, Fe-B-C, Fe-Al, Co-V-Fe, Co-Ta, Co-Zr, Co-Nb-Zr, Co-Ti, Co-Nb-Ta, Co-Ni-Zr, Fe-Ni-P and Fe-Co-Zr.
Claim 11
Dependent Claim
25 words
The method 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 12
Dependent Claim
25 words
The method 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 13
Dependent Claim
27 words
The method 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 14
Dependent Claim
25 words
The method 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 15
Dependent Claim
25 words
The method 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 16
Dependent Claim
25 words
The method as claimed in claim 1, wherein said soft magnetic film layers and said vertical magnetization film layers are formed by high-speed continuous sputtering.
Claim 17
Dependent Claim
33 words
The method as claimed in claim 1, further comprising the step of providing said recording medium with a base layer, an intermediate layer, and an overcoat layer on each side of said support.
References Cited (Backward Citations)
US4680197A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-09-11 | 1993-03-13 | 1993-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-11 | 1997-03-13 | 1997-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-11 | 2001-03-13 | 2001-09-12 | $7700.00 | Window Closed / Lapsed |