Patent US4431702A successfully refreshed from Google Patents.
US4431702A
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Magnetic recording medium
Assignee: TDK Corp
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Filing: 1982-03-24
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Granted: 1984-02-14
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Expires: 2002-03-24
Abstract
Abstract A magnetic recording medium having a magnetic layer comprising a magnetic powder and a resin binder, which is characterized by that the magnetic layer contains an ethylene trifluoride chloride polymer of a low degree of polymerization and a fatty acid ester.
Inventors
- 👤 Hiroshi Kawahara
- 👤 Hitoshi Azegami
- 👤 Eiji Horigome
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:43
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/71; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/3154; Y10T428/31544
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
63 words
In a magnetic recording medium of a magnetic layer comprising a magnetic powder and a resin binder on a support, the improvement comprising: said magnetic layer additionally containing from 0.5-5% by wt of an ethylene trifluoride chloride polymer of a low degree of polymerization and from 1-10% by wt of a fatty acid ester having a C 12 -C 18 carbon atom content.
Claim 2
Dependent Claim
63 words
In a magnetic recording medium of a magnetic layer comprising a magnetic powder and a resin binder on a support, the improvement comprising: said magnetic layer additionally containing from 0.5-5% by wt of an ethylene trifluoride chloride polymer of a low degree of polymerization and from 1-10% by wt of a fatty acid ester having a C 12 -C 18 carbon atom content.
Claim 3
Dependent Claim
20 words
The magnetic recording medium of claim 1, wherein said ethylene trifluoride chloride polymer has a degree of polymerization of 7-12.
Claim 4
Dependent Claim
20 words
The magnetic recording medium of claim 1 or 2, wherein said fatty acid ester is a sorbitan fatty acid ester.
Claim 5
Dependent Claim
26 words
The magnetic recording medium of claim 3, wherein said sorbitan fatty acid ester is a monoester, a diester, a triester or a combination of these esters.
Claim 6
Dependent Claim
28 words
The magnetic recording medium of claim 1, wherein the ratio of the ethylene trifluoride chloride polymer to said fatty acid ester ranges from 1:2 to 5:1 by weight.
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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) | 1987-02-13 | 1987-08-15 | 1988-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-13 | 1991-08-15 | 1992-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-13 | 1995-08-15 | 1996-02-14 | $7700.00 | Window Closed / Lapsed |