US4201809A
Expired / Lapsed
US
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Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1978-07-18
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Granted: 1980-05-06
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Expires: 1998-07-18
Abstract
Abstract This invention relates to a magnetic recording medium having on a non-magnetic support a magnetic layer comprising a ferromagnetic powder dispersed in a binder, in which the magnetic layer contains a compound represented by the following general formula (I), ##STR1## wherein R represents a residual radical of trimethylolethane, trimethylolpropane or pentaerythritol, R' represents a residual radical of a fatty acid having at least 5 carbon atoms and n represents an integer of 2 to 4.
Inventors
- 👤 Hiroshi Ogawa
- 👤 Yasuo Tamai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:12
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; Y10T428/26; Y10T428/266; Y10T428/31504; Y10T428/31678; Y10T428/31717; Y10T428/31786; Y10T428/31855; Y10T428/31938
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
94 words
A magnetic recording medium having on a non-magnetic support a magnetic layer comprising a ferromagnetic powder dispersed in a binder, in which the magnetic layer contains a compound represented by the following general formula (I), ##STR6## wherein R represents a residual radical of trimethylolethane, trimethylolpropane or pentaerythritol, R' represents a residual radical of a fatty acid having at least 5 carbon atoms and n represents an integer of 2 to 4 said compound (I) being present in a proportion of 0.1 to 5 parts by weight to 100 parts by weight of ferromagnetic powder.
Claim 2
Dependent Claim
94 words
A magnetic recording medium having on a non-magnetic support a magnetic layer comprising a ferromagnetic powder dispersed in a binder, in which the magnetic layer contains a compound represented by the following general formula (I), ##STR6## wherein R represents a residual radical of trimethylolethane, trimethylolpropane or pentaerythritol, R' represents a residual radical of a fatty acid having at least 5 carbon atoms and n represents an integer of 2 to 4 said compound (I) being present in a proportion of 0.1 to 5 parts by weight to 100 parts by weight of ferromagnetic powder.
Claim 3
Dependent Claim
21 words
The magnetic recording medium as claimed in claim 1, wherein R' is an alkyl group having 5 to 17 carbon atoms.
Claim 4
Dependent Claim
21 words
The magnetic recording medium as claimed in claim 1, wherein R' is an alkenyl group having 5 to 17 carbon atoms.
Claim 5
Dependent Claim
35 words
The magnetic recording medium as claimed in claim 1, wherein the ferromagnetic powder consists of at least one member selected from the group consisting of ferromagnetic iron oxides, ferromagnetic chromium dioxide and ferromagnetic alloy powders.
Claim 6
Dependent Claim
23 words
The magnetic recording medium as claimed in claim 4, wherein the ferromagnetic iron oxides are represented by the general formula FeOx wherein 1.33≦×≦1.50.
Claim 7
Dependent Claim
38 words
The magnetic recording medium as claimed in claim 4, wherein the ferromagnetic iron oxides contain 0 to 10 atomic % of at least one metal selected from the group consisting of Cr, Mn, Co, Ni, Cu and Zn.
Claim 8
Dependent Claim
50 words
The magnetic recording medium as claimed in claim 4, wherein the ferromagnetic chromium dioxide contains 0 to 20% by weight of at least one metal selected from the group consisting of Na, K, Ti, V, Mn, Fe, Co, Ni, Tc, Ru, Sn, Ce, Pb, P, Sb, Te and oxides thereof.
Claim 9
Dependent Claim
39 words
The magnetic recording medium as claimed in claim 4, wherein the ferromagnetic alloy powder contains at least 75% by weight of at least one metal selected from the group consisting of Fe, Co, Ni, Fe-Co, Fe-Ni, Co-Ni and Fe-Co-Ni.
Claim 10
Dependent Claim
28 words
The magnetic recording medium as claimed in claim 1, wherein the binder is at least one material selected from the group consisting of thermoplastic resins and thermosetting resins.
Claim 11
Dependent Claim
33 words
The magnetic recording medium as claimed in claim 1, wherein the binder is used in a proportion of 10 to 100 parts by weight to 100 parts by weight of the ferromagnetic powder.
Claim 12
Dependent Claim
29 words
The magnetic recording medium as claimed in claim 1, wherein the magnetic layer further contains additives selected from the group consisting of dispersing agents, lubricants, abrasives and antistatic agents.
Claim 13
Dependent Claim
38 words
The magnetic recording medium as claimed in claim 1, wherein the non-magnetic support is of a material selected from the group consisting of polyethylene terephthalate, polyethylene-2,6-naphthalate, polypropylene, cellulose triacetate, cellulose diacetate, polycarbonate, copper, aluminum, zinc, glass and ceramics.
Claim 14
Dependent Claim
27 words
The magnetic recording medium as claimed in claim 1, wherein the non-magnetic support is a film, tape or sheet having a thickness of 2 to 50 μm.
Claim 15
Dependent Claim
26 words
The magnetic recording medium as claimed in claim 1, wherein the non-magnetic support is a disk or card having a thickness of 0.5 to 10 mm.
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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) | 1983-05-06 | 1983-11-05 | 1984-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-06 | 1987-11-05 | 1988-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-06 | 1991-11-05 | 1992-05-06 | $7700.00 | Window Closed / Lapsed |