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Patent US3687726A successfully refreshed from Google Patents.
US3687726A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alumina coated chromium dioxide
Assignee: EIDP Inc
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Filing: 1970-10-19
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Granted: 1972-08-29
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Expires: 1990-10-19
Abstract
Abstract FERROMAGNETIC CHROMIUM DIOXIDE IS STABILIZED WITH A COATING OF ALUMINA.
Inventors
- 👤 Donald George Pye
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:49
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/0302; H01F1/0311; H01F1/0313; G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70636; G11B5/712; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2993
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |