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US4547425A
Expired / Lapsed
US
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Magnetic recording media
Assignee: Victor Company of Japan Ltd
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Filing: 1983-07-18
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Granted: 1985-10-15
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Expires: 2003-07-18
Abstract
Abstract Magnetic recording media are described which are characterized by a recording layer formed on at least one side of a support and made of magnetic particles and a TiO powder dispersed throughout a resin binder. The TiO powder is used in an amount of 0.1 to 35 wt % of the magnetic particles and has an average size of about 0.015 to 5 microns.
Inventors
- 👤 Tsunehide Naruse
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:44
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/708; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
86 words
A magnetic recording medium comprising a substrate, and a recording layer formed on at least one side of the substrate and made of magnetic particles selected from the group consisting of ferromagnetic metal oxide particles and ferromagnetic metal particles and from 0.15 to 35 wt %, based on said magnetic particles, of a non-magnetic powder consisting essentially of TiO powder having an average particle size of from 0.015 to 5.0 microns, both of said magnetic particles and said TiO powder being dispersed throughout a resin binder.
Claim 2
Dependent Claim
86 words
A magnetic recording medium comprising a substrate, and a recording layer formed on at least one side of the substrate and made of magnetic particles selected from the group consisting of ferromagnetic metal oxide particles and ferromagnetic metal particles and from 0.15 to 35 wt %, based on said magnetic particles, of a non-magnetic powder consisting essentially of TiO powder having an average particle size of from 0.015 to 5.0 microns, both of said magnetic particles and said TiO powder being dispersed throughout a resin binder.
Claim 3
Dependent Claim
19 words
A magnetic recording medium according to claim 1, wherein said substrate has the recording layer on one side thereof.
Claim 4
Dependent Claim
19 words
A magnetic recording medium according to claim 1, wherein said substrate has the recording layer on each side thereof.
Claim 5
Dependent Claim
35 words
A magnetic recording medium according to claim 1, wherein said non-magnetic TiO powder is a mixture of TiO powders of different sizes provided that its maximum size is below a thickness of the recording medium.
Claim 6
Dependent Claim
36 words
A magnetic recording medium according to claim 1 wherein the TiO powder comprises black cubic crystals having a specific gravity of 4.0 to 4.9, a pH of 7.0±1.0 and an electric resistance of 10 -2 ohm-cm.
References Cited (Backward Citations)
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Cited
US4275115A
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US4326229A
Cited
US4395447A
Cited
US4420408A
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US4423452A
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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) | 1988-10-14 | 1989-04-15 | 1989-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-14 | 1993-04-15 | 1993-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-14 | 1997-04-15 | 1997-10-15 | $7700.00 | Window Closed / Lapsed |