US4592948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: TDK Corp
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Filing: 1983-12-20
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Granted: 1986-06-03
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Expires: 2003-12-20
Abstract
Abstract A magnetic recording medium for use in video and other applications is presented which comprises a substrate, a continuous thin magnetic layer of cobalt and at least one selected from nickel, chromium, and oxygen, preferably obliquely evaporated on the substrate, and a topcoat formed over the magnetic layer and consisting of a monoalkylamine in which the alkyl contains 10 to 22 carbon atoms.
Inventors
- 👤 Osamu Kohmoto
- 👤 Yasufumi Takasugi
- 👤 Hiroshi Sugihara
- 👤 Masaharu Nishimatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:26
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/24975; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
53 words
A magnetic recording medium comprising a substrate, a continuous thin magnetic layer on the substrate, and a topcoat formed over the magnetic layer, characterized in that the topcoat consists of a compound having the formula: RNH.sub.2 where R is an alkyl radical having 10 to 22 carbon atoms deposited by evaporation or sputtering.
Claim 2
Dependent Claim
53 words
A magnetic recording medium comprising a substrate, a continuous thin magnetic layer on the substrate, and a topcoat formed over the magnetic layer, characterized in that the topcoat consists of a compound having the formula: RNH.sub.2 where R is an alkyl radical having 10 to 22 carbon atoms deposited by evaporation or sputtering.
Claim 3
Dependent Claim
19 words
The magnetic recording medium according to claim 1 wherein the alkyl radical represented by R is of straight chain.
Claim 4
Dependent Claim
14 words
The magnetic recording medium according to claim 2 wherein the alkyl radical is unsubstituted.
Claim 5
Dependent Claim
24 words
The magnetic recording medium according to claim 1 wherein R is selected from straight chain, unsubstituted alkyl radicals having 12 to 22 carbon atoms.
Claim 6
Dependent Claim
20 words
The magnetic recording medium according to claim 1 wherein the topcoat has a thickness of not more than 0.3 microns.
Claim 7
Dependent Claim
16 words
The magnetic recording medium according to claim 1 wherein the magnetic layer consists essentially of cobalt.
Claim 8
Dependent Claim
26 words
The magnetic recording medium according to claim 6 wherein the magnetic layer contains nickel and the weight ratio of cobalt to nickel is at least 1.5.
Claim 9
Dependent Claim
27 words
The magnetic recording medium according to claim 6 wherein the magnetic layer contains chromium and the weight ratio of chromium to cobalt ranges from 0.001 to 0.1.
Claim 10
Dependent Claim
32 words
The magnetic recording medium according to claim 7 wherein magnetic layer further contains chromium and the weight ratio of chromium to the sum of cobalt and nickel ranges from 0.001 to 0.1.
Claim 11
Dependent Claim
27 words
The magnetic recording medium according to claim 6 wherein the magnetic layer contains oxygen and the atomic ratio of oxygen to cobalt is not more than 0.45.
Claim 12
Dependent Claim
33 words
The magnetic recording medium according to claim 7 wherein the magnetic layer further contains oxygen and the atomic ratio of oxygen to the sum of cobalt and nickel is not more than 0.45.
Claim 13
Dependent Claim
31 words
The magnetic recording medium according to claim 1 or 6 wherein the magnetic layer consists of a coalescence of particles of columnar structure oriented oblique to the normal to the substrate.
Claim 14
Dependent Claim
20 words
The magnetic recording medium according to claim 12 wherein the magnetic layer has a thickness of 0.05 to 0.5 microns.
Claim 15
Dependent Claim
28 words
The magnetic recording medium according to claim 6, wherein said magnetic layer further includes at least one member selected from the group consisting of nickel, chromium and oxygen.
References Cited (Backward Citations)
US4429024A
Cited
US4425404A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-02 | 1989-12-02 | 1990-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-02 | 1993-12-02 | 1994-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-02 | 1997-12-02 | 1998-06-03 | $7700.00 | Window Closed / Lapsed |