US4416943A
Expired / Lapsed
US
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Magnetic recording medium
Assignee: TDK Corp
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Filing: 1981-07-23
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Granted: 1983-11-22
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Expires: 2001-07-23
Abstract
Abstract A magnetic recording medium comprises cobalt as a main component and at least one of zinc, rhodium and iridium as an additional component of an alloy of a magnetic layer.
Inventors
- 👤 Seitoku Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:03
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70605; G11B5/70621; C; C22; C22C; C22C19/00; C22C19/07; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/261; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
82 words
A magnetic recording medium comprising a substrate layer and at least one magnetic layer consisting essentially of cobalt as a main component and zinc or iridium as an additional component wherein the ratio of Co:Ir is 90:10 and Co:Zn is 86:14 of an alloy of a magnetic layer wherein axes of easy magnetization of said components are substantially perpendicular to a surface of said magnetic layer and thickness of said magnetic layer is in a range of 500 Å to 3 μm.
Claim 2
Dependent Claim
82 words
A magnetic recording medium comprising a substrate layer and at least one magnetic layer consisting essentially of cobalt as a main component and zinc or iridium as an additional component wherein the ratio of Co:Ir is 90:10 and Co:Zn is 86:14 of an alloy of a magnetic layer wherein axes of easy magnetization of said components are substantially perpendicular to a surface of said magnetic layer and thickness of said magnetic layer is in a range of 500 Å to 3 μm.
Claim 3
Dependent Claim
86 words
The magnetic recording medium according to claim 1 wherein the upper layer of a two layer magnetic structure consists essentially of cobalt as a main component and zinc or iridium as an additional component wherein the ratio of Co:Ir is 90:10 and Co:Zn is 86:24 of an alloy of a magnetic layer wherein axes of easy magnetization of said components are substantially perpendicular to a surface of said magnetic layer and thickness of said magnetic layer is in a range of 500 Å to 3 μm.
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) | 1986-11-21 | 1987-05-23 | 1987-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-21 | 1991-05-23 | 1991-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-21 | 1995-05-23 | 1995-11-22 | $7700.00 | Window Closed / Lapsed |