US4460653A
Expired / Lapsed
US
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Magnetic recording medium
Assignee: TDK Corp
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Filing: 1983-10-24
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Granted: 1984-07-17
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Expires: 2003-10-24
Abstract
Abstract A magnetic recording medium, comprising a magnetic layer and a non-magnetic substrate therefor, which magnetic layer is formed by dispersing magnetic powder in a vehicle formed of a copolymer containing vinyl chloride, another monomer copolymerizable with said vinyl chloride, a vinyl ester of an alkanoic acid and a saponification product thereof and having an OH/CH absorption ratio of 0.2 to 0.7 in the infrared absorption spectrum, and a rubbery binder.
Inventors
- 👤 Hitoshi Azegami
- 👤 Hiroshi Kawahara
- 👤 Fujio Shibata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:08
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7023; G11B5/7021; G11B5/7022; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31609; Y10T428/31855; Y10T428/31935
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
68 words
A magnetic recording medium, comprising a magnetic layer and a non-magnetic substrate therefor, which magnetic layer is formed by dispersing magnetic powder in a vehicle formed of a copolymer containing vinyl chloride, another monomer copolymerizable with vinyl chloride, a vinyl ester of an alkanoic acid and a saponification product thereof having an OH/CH absorption ratio of 0.2 to 0.7 in the infrared absorption spectrum, and a rubbery binder.
Claim 2
Dependent Claim
68 words
A magnetic recording medium, comprising a magnetic layer and a non-magnetic substrate therefor, which magnetic layer is formed by dispersing magnetic powder in a vehicle formed of a copolymer containing vinyl chloride, another monomer copolymerizable with vinyl chloride, a vinyl ester of an alkanoic acid and a saponification product thereof having an OH/CH absorption ratio of 0.2 to 0.7 in the infrared absorption spectrum, and a rubbery binder.
Claim 3
Dependent Claim
48 words
A magnetic recording medium according to claim 1, containing 50 to 90% by weight vinyl chloride, 5 to 1.5% by weight of another monomer copolymerizable with vinyl chloride, 40 to 5% by weight vinyl ester of alkanoic acid, balance saponification product of said vinyl ester of alkanoic acid.
Claim 4
Dependent Claim
25 words
A magnetic recording medium according to claim 1, containing 10 to 60 parts by weight rubbery binder per 100 parts by weight of total resin.
Claim 5
Dependent Claim
27 words
A magnetic recording medium according to claim 1, wherein said rubbery binder is at least one member selected from the group consisting of acrylontitrilebutadiene rubber and polyurethane.
Claim 6
Dependent Claim
70 words
A magnetic recording medium, comprising a magnetic layer and a non-magnetic substrate therefor, which magnetic layer is formed by dispersing magnetic powder in a vehicle formed of a copolymer containing vinyl chloride, another monomer copolymerizable with vinyl chloride, a vinyl ester of an alkanoic acid and a saponification product thereof having an OH/CH absorption ratio of 0.2 to 0.7 in the infrared absorption spectrum, a rubbery binder and a polyisocyanate.
Claim 7
Dependent Claim
70 words
A magnetic recording medium, comprising a magnetic layer and a non-magnetic substrate therefor, which magnetic layer is formed by dispersing magnetic powder in a vehicle formed of a copolymer containing vinyl chloride, another monomer copolymerizable with vinyl chloride, a vinyl ester of an alkanoic acid and a saponification product thereof having an OH/CH absorption ratio of 0.2 to 0.7 in the infrared absorption spectrum, a rubbery binder and a polyisocyanate.
Claim 8
Dependent Claim
27 words
A magnetic recording medium according to claim 5, containing 10 to 60 parts by weight rubbery binder per 100 parts by weight of total resin excluding polyisocyanate.
Claim 9
Dependent Claim
23 words
A magnetic recording medium according to claim 5, containing 5 to 30% by weight polyisocyanate based on the solids content of said vehicle.
Claim 10
Dependent Claim
27 words
A magnetic recording medium according to claim 5, wherein said rubbery binder is at least one member selected from the group consisting of acrylonitrilebutadiene rubber and polyurethane.
Claim 11
Dependent Claim
48 words
A magnetic recording medium according to claim 6, containing 50 to 90% by weight vinyl chloride, 5 to 1.5% by weight of another monomer copolymerizable with vinyl chloride, 40 to 5% by weight vinyl ester of alkanoic acid, balance saponification product of said vinyl ester of alkanoic acid.
Claim 12
Dependent Claim
23 words
A magnetic recording medium according to claim 6, containing 10 to 25% by weight polyisocyanate based on the solids content of said vehicle.
References Cited (Backward Citations)
US4234438A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-17 | 1988-01-16 | 1988-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-17 | 1992-01-16 | 1992-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-17 | 1996-01-16 | 1996-07-17 | $7700.00 | Window Closed / Lapsed |