US4307154A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: TDK Corp
•
Filing: 1979-11-09
•
Granted: 1981-12-22
•
Expires: 1999-11-09
Abstract
Abstract A magnetic recording medium having improved electromagnetic conversion characteristics and physical properties prepared by using a three-component binder consisting of a polyurethane resin, a phenoxy resin and a vinyl chloride-vinylidene chloride resin.
Inventors
- 👤 Akihiko Hosaka
- 👤 Kazushi Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:28
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7021; G11B5/7022; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31511; Y10T428/31551; Y10T428/31565; Y10T428/31573; Y10T428/3158; Y10T428/31609
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
69 words
A magnetic recording medium comprising a base support and a layer of a magnetic coating material on said base support, said magnetic coating material comprising a magnetic material dispersed in a binder containing three resin components, namely from 30 to 70% of a polyurethane resin, from 15 to 45% of a phenoxy resin and from 5 to 45% of a vinyl chloride-vinylidene chloride resin, all percentages being by weight.
Claim 2
Dependent Claim
69 words
A magnetic recording medium comprising a base support and a layer of a magnetic coating material on said base support, said magnetic coating material comprising a magnetic material dispersed in a binder containing three resin components, namely from 30 to 70% of a polyurethane resin, from 15 to 45% of a phenoxy resin and from 5 to 45% of a vinyl chloride-vinylidene chloride resin, all percentages being by weight.
Claim 3
Dependent Claim
20 words
A magnetic recording medium according to claim 1, wherein said powdered magnetic material is Co-doped γ-Fe 2 O 3 .
Claim 4
Dependent Claim
16 words
A magnetic recording medium according to claim 1, wherein said base support is a polyester film.
References Cited (Backward Citations)
US3247017A
Cited
US3320090A
Cited
US3740266A
Cited
US3689317A
Cited
US3650828A
Cited
US3840400A
Cited
JPS5110914A
Cited
US3911196A
Cited
SU661600A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-12-21 | 1985-06-22 | 1985-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-21 | 1989-06-22 | 1989-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-21 | 1993-06-22 | 1993-12-22 | $7700.00 | Window Closed / Lapsed |