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US4379809A
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Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1981-09-30
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Granted: 1983-04-12
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Expires: 2001-09-30
Abstract
Abstract A magnetic recording medium which comprises a non-magnetic support having thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, with the magnetic layer further containing an organoaluminum compound or with the surface of the ferromagnetic particles being treated with an organoaluminum compound.
Inventors
- 👤 Akihiro Matsufuji
- 👤 Tadashi Ishiguro
- 👤 Nobuo Tsuji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:39
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7028; G11B5/712; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
65 words
A magnetic recording medium which comprises a non-magnetic support having thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, with the surface of said ferromagnetic particles being treated with an aluminum alcoholate of the formula (I): Al(OR).sub.3 (I) wherein each R, which may be the same or different, represents a straight or branched chain alkyl group having 1 to 10 carbon atoms.
Claim 2
Dependent Claim
65 words
A magnetic recording medium which comprises a non-magnetic support having thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, with the surface of said ferromagnetic particles being treated with an aluminum alcoholate of the formula (I): Al(OR).sub.3 (I) wherein each R, which may be the same or different, represents a straight or branched chain alkyl group having 1 to 10 carbon atoms.
Claim 3
Dependent Claim
77 words
A magnetic recording medium which comprises a non-magnetic support having thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, with the surface of said ferromagnetic particles being treated with an aluminum chelate compound of the formula (II): ##STR2## wherein R 1 is a straight or branched chain alkyl group having 1 to 10 carbon atoms, and R 2 is a straight or branched chain alkyl or alkenyl group having up to 20 carbon atoms.
Claim 4
Dependent Claim
77 words
A magnetic recording medium which comprises a non-magnetic support having thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, with the surface of said ferromagnetic particles being treated with an aluminum chelate compound of the formula (II): ##STR2## wherein R 1 is a straight or branched chain alkyl group having 1 to 10 carbon atoms, and R 2 is a straight or branched chain alkyl or alkenyl group having up to 20 carbon atoms.
Claim 5
Dependent Claim
20 words
A magnetic recording medium according to claim 1 or 2, wherein the ferromagnetic particles are particles of ferromagnetic iron oxide.
Claim 6
Dependent Claim
19 words
A magnetic recording medium according to claim 1 or 2, wherein the ferromagnetic particles are particles of cobalt ferrite.
Claim 7
Dependent Claim
20 words
A magnetic recording medium according to claim 1 or 2, wherein the ferromagnetic particles are particles of ferromagnetic chromium dioxide.
Claim 8
Dependent Claim
23 words
A magnetic recording medium according to claim 1 or 2, wherein the ferromagnetic particles are fine particles of ferromagnetic metals or alloys thereof.
References Cited (Backward Citations)
US3860451A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-11 | 1986-10-11 | 1987-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-11 | 1990-10-11 | 1991-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-11 | 1994-10-11 | 1995-04-12 | $7700.00 | Window Closed / Lapsed |