US4186228A
Expired / Lapsed
US
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Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1978-09-07
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Granted: 1980-01-29
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Expires: 1998-09-07
Abstract
Abstract A magnetic recording medium comprising a non-magnetic support having thereon a magnetic recording layer containing a finely divided ferromagnetic powder, a binder and at least one 1,2-epoxyalkane represented by the general formula (I) ##STR1## wherein R represents an alkyl group having 10 to 30 carbon atoms; in an amount of about 0.05 to about 3 parts by weight per 100 parts by weight of the ferromagnetic powder.
Inventors
- 👤 Hiroshi Ogawa
- 👤 Matsuaki Nakamura
- 👤 Yasuo Tamai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:23
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7023; G11B5/706; G11B5/70626; G11B5/70642; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31511; Y10T428/31678
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
67 words
A magnetic recording medium comprising a non-magnetic support having thereon a magnetic recording layer containing a finely divided ferromagnetic powder, a binder and at least one 1,2-epoxyalkane represented by the general formula (I) ##STR12## wherein R represents an alkyl group having 10 to 30 carbon atoms; in an amount of about 0.05 to about 3 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 2
Dependent Claim
67 words
A magnetic recording medium comprising a non-magnetic support having thereon a magnetic recording layer containing a finely divided ferromagnetic powder, a binder and at least one 1,2-epoxyalkane represented by the general formula (I) ##STR12## wherein R represents an alkyl group having 10 to 30 carbon atoms; in an amount of about 0.05 to about 3 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 3
Dependent Claim
21 words
The magnetic recording medium of claim 1, wherein R is a straight chain alkyl group or a branched chain alkyl group.
Claim 4
Dependent Claim
76 words
The magnetic recording medium of claim 2, wherein said alkyl group is a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an eicosyl group, a heneicosyl group, a docosyl group, a tricosyl group, a tetracosyl group, a pentacosyl group, a hexacosyl group, a heptacosyl group, an octacosyl group, a nonacosyl group, or a triacontyl group.
Claim 5
Dependent Claim
18 words
The magnetic recording medium of claim 1, wherein said 1,2-epoxyalkane is 1,2-epoxydodecane, 1,2-epoxytetradecane, 1,2-epoxyhexadecane, 1,2-epoxyoctadecane, 1,2-epoxydocosane or 1,2-epoxydotriacontane.
Claim 6
Dependent Claim
25 words
The magnetic recording medium of claim 1, wherein said ferromagnetic powder is a ferromagnetic iron oxide, a ferromagnetic chromium dioxide or a ferromagnetic alloy powder.
Claim 7
Dependent Claim
149 words
The magnetic recording medium of claim 5, wherein said ferromagnetic iron oxide is an iron oxide represented by the formula FeO.sub.x wherein x is in the range of 1.33≦x≦1.50, which may contain up to about 10 atomic % of Cr, Mn, Co, Ni, Cu or Zn, as a divalent metal, said ferromagnetic chromium dioxide is CrO 2 in which up to about 20% by weight of Na, K, Ti, V, Mn, Fe, Co, Ni, Tc, Ru, Sn, Ce, Tb, P, Sb or Te, or an oxide thereof may be present, and said ferromagnetic alloy powder contains more than about 75% by weight of at least one ferromagnetic metal and about 20% by weight or less of Al, Si, S, Sc, Ti, V, Cr, Mn, Cu, Zn, Y, Mo, Rh, Pd, Ag, Sn, Sb, Te, Ba, Ta, W, Re, Au, Hg, Pb, Bi, La, Ce, Pr, Nd, B or P.
References Cited (Backward Citations)
US3987232A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-28 | 1983-07-30 | 1984-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-28 | 1987-07-30 | 1988-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-28 | 1991-07-30 | 1992-01-29 | $7700.00 | Window Closed / Lapsed |