US4600650A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: TDK Corp
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Filing: 1983-03-14
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Granted: 1986-07-15
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Expires: 2003-03-14
Abstract
Abstract A magnetic recording medium is composed of a substrate coated with a magnetic layer comprising a magnetic powder and a binder, wherein the binder comprises from 20 to 60% by weight of a polyurethane resin, from 20 to 60% by weight of an epoxy resin, from 15 to 55% by weight of a vinyl chloride-vinyl acetate copolymer resin and a polyisocyanate.
Inventors
- 👤 Akihiko Hosaka
- 👤 Kiyotaka Okuyama
- 👤 Kiyoto Kanazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:53
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7021; G11B5/7022; C; C08; C08L; C08L75/00; C08L75/04; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31511; Y10T428/31551; Y10T428/31609; Y10T428/31855; Y10T428/31935
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
67 words
In a magnetic recording medium composed of a substrate coated with a magnetic layer comprising a magnetic powder and a binder, an improvement wherein the binder comprises from 20 to 60% by weight of a metal sulfonate group free polyurethane resin, from 20 to 60% by weight of an epoxy resin, from 15 to 55% by weight of a vinyl chloride-vinyl acetate copolymer resin and a polyisocyanate.
Claim 2
Dependent Claim
67 words
In a magnetic recording medium composed of a substrate coated with a magnetic layer comprising a magnetic powder and a binder, an improvement wherein the binder comprises from 20 to 60% by weight of a metal sulfonate group free polyurethane resin, from 20 to 60% by weight of an epoxy resin, from 15 to 55% by weight of a vinyl chloride-vinyl acetate copolymer resin and a polyisocyanate.
Claim 3
Dependent Claim
31 words
The magnetic recording medium according to claim 1 wherein the amount of the polyisocyanate is from 5 to 20% by weight, based on the total amount by weight of said resins.
References Cited (Backward Citations)
US4152485A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |