Patent US5034243A successfully refreshed from Google Patents.
US5034243A
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Method for magnetic orientation of magnetic recording medium using Meissner effect of high Tc superconductor
Assignee: Hitachi Ltd
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Filing: 1989-11-01
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Granted: 1991-07-23
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Expires: 2009-11-01
Abstract
Abstract A method for magnetic orientation of a magnetic recording medium using Meissner effect of a superconductor and a system therefor and a magnetic recording medium produced thereby. The magnetic particles of plate hexagonal barium ferrite in the magnetic coating are allowed to orient in the longitudinal direction thereof so that a magnetic recording medium having a magnetic orientation in such direction with the magnetic particles can be obtained.
Inventors
- 👤 Katsuyoshi Chiba
- 👤 Masayuki Katsumoto
- 👤 Yasutaro Uesaka
- 👤 Heigo Ishihara
- 👤 Naoki Kodama
- 👤 Hajime Fukke
- 👤 Iwao Matsuyama
- 👤 Tsuneo Suganuma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:37
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/842; G11B5/845; G11B5/10; G11B5/11
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
72 words
A method for magnetic orientation of a magnetic recording medium by disposing a magnetic coating film containing magnetic particles between a magnet and an oxide superconductor having an operating temperature of 77° K., while said magnetic particles are still in a mobile state, and applying a magnetic flux having a magnetic component in the longitudinal direction of the magnetic coating film, wherein said magnetic flux is oriented due to the Meissner effect.
Claim 2
Independent Claim
72 words
A method for magnetic orientation of a magnetic recording medium by disposing a magnetic coating film containing magnetic particles between a magnet and an oxide superconductor having an operating temperature of 77° K., while said magnetic particles are still in a mobile state, and applying a magnetic flux having a magnetic component in the longitudinal direction of the magnetic coating film, wherein said magnetic flux is oriented due to the Meissner effect.
Claim 3
Dependent Claim
24 words
The method for magnetic orientation of a magnetic recording medium according to claim 1, wherein the strength of said magnetic flux fluctuates with time.
Claim 4
Independent Claim
101 words
A method for magnetic orientation of a magnetic recording medium, comprising the steps of disposing the magnetic recording medium in a space between a magnet and an oxide superconductor having an operating temperature of 77° K. where a magnetic flux exists, said medium comprising a substrate having magnetic particles from a powdery or dispersed coating material applied thereon, said superconductor being positioned in such a manner that said magnetic flux is aligned in a direction substantially parallel to the plane of said substrate of said magnetic recording medium in the vicinity thereof, thereby orienting said magnetic particles in said magnetic flux.
Claim 5
Independent Claim
101 words
A method for magnetic orientation of a magnetic recording medium, comprising the steps of disposing the magnetic recording medium in a space between a magnet and an oxide superconductor having an operating temperature of 77° K. where a magnetic flux exists, said medium comprising a substrate having magnetic particles from a powdery or dispersed coating material applied thereon, said superconductor being positioned in such a manner that said magnetic flux is aligned in a direction substantially parallel to the plane of said substrate of said magnetic recording medium in the vicinity thereof, thereby orienting said magnetic particles in said magnetic flux.
Claim 6
Independent Claim
110 words
A method for magnetic orientation of a magnetic recording medium comprising forming a magnetic coating film on a substrate by applying a magnetic coating dispersion of magnetic particles in a high molecular weight binder, disposing the magnetic coating film between a magnet and an oxide superconductor having an operating temperature of 77° K. and applying a magnetic flux to said magnetic coating film on said substrate to orient said magnetic particles, wherein said superconductor is disposed in such a manner that said magnetic flux is aligned in a direction substantially parallel to the plane of said substrate in the vicinity thereof, thereby orienting said magnetic particles under said magnetic flux.
Claim 7
Independent Claim
110 words
A method for magnetic orientation of a magnetic recording medium comprising forming a magnetic coating film on a substrate by applying a magnetic coating dispersion of magnetic particles in a high molecular weight binder, disposing the magnetic coating film between a magnet and an oxide superconductor having an operating temperature of 77° K. and applying a magnetic flux to said magnetic coating film on said substrate to orient said magnetic particles, wherein said superconductor is disposed in such a manner that said magnetic flux is aligned in a direction substantially parallel to the plane of said substrate in the vicinity thereof, thereby orienting said magnetic particles under said magnetic flux.
Claim 8
Dependent Claim
50 words
The method for magnetic orientation of a magnetic recording medium according to claim 1, wherein said magnetic recording medium is a magnetic recording medium having a magnetic orientation parallel to the plane thereof and the magnetic coating film of said medium recording contains magnetic particles of plate hexagonal barium ferrite.
Claim 9
Dependent Claim
29 words
The method for magnetic orientation of a magnetic recording medium of claim 1 wherein the strength of said magnetic flux varies in a pulse state with respect to time.
References Cited (Backward Citations)
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JPS6224430A
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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) | 1994-07-22 | 1995-01-21 | 1995-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-22 | 1999-01-21 | 1999-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-22 | 2003-01-21 | 2003-07-23 | $7700.00 | Window Closed / Lapsed |