US3278263A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ferromagnetic chromium dioxide and preparation thereof
Assignee: EIDP Inc
•
Filing: 1964-11-27
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Granted: 1966-10-11
•
Expires: 1984-11-27
Abstract
No abstract record available.
Inventors
- 👤 Norman L Cox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:28
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70636; B; B82; B82Y; B82Y30/00; C; C01; C01G; C01G37/00; C01G37/02; C01P; C01P2002/00; C01P2002/60; C01P2004/00; C01P2004/51; C01P2004/52; C01P2004/54; C01P2004/60; C01P2004/62; C01P2004/64; C01P2006/00; C01P2006/42; C01P2006/60; C01P2006/80; C01P2006/82
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
A FERROMAGNETIC CHROMIUM DIOXIDE FREE OF MODIFYING MATERIAL AND HAVING AN INTRINSIC COERCIVE FORCE ABOVE 200 OERSTEDS, A SATURATION INDUCTION PER GRAM IN THE RANGE OF 80-100 GAUSS-CM.3/G. AND A REMANENCE RATIO OF AT LEAST 0.35, SAID FERROMAGNETIC CHROMIUM DIOXIDE BEING IN THE FORM OF HIGHLY UNIFORM, FINE, ACICULAR PARTICLES OF A TETRAGONAL CRYSTAL STRUCTURE OF THE RUTILE TYPE RANGING UP TO 1.5 MICRONS IN LENGTH, AND HAVING A MEDIAN AXIAL RATIO RANGING FROM 2:1 TO 20:1, ESSENTIALLY ALL OF WHICH CONSTITUTE SINGLE MAGNETIC DOMAINS.
Claim 2
Dependent Claim
85 words
A FERROMAGNETIC CHROMIUM DIOXIDE FREE OF MODIFYING MATERIAL AND HAVING AN INTRINSIC COERCIVE FORCE ABOVE 200 OERSTEDS, A SATURATION INDUCTION PER GRAM IN THE RANGE OF 80-100 GAUSS-CM.3/G. AND A REMANENCE RATIO OF AT LEAST 0.35, SAID FERROMAGNETIC CHROMIUM DIOXIDE BEING IN THE FORM OF HIGHLY UNIFORM, FINE, ACICULAR PARTICLES OF A TETRAGONAL CRYSTAL STRUCTURE OF THE RUTILE TYPE RANGING UP TO 1.5 MICRONS IN LENGTH, AND HAVING A MEDIAN AXIAL RATIO RANGING FROM 2:1 TO 20:1, ESSENTIALLY ALL OF WHICH CONSTITUTE SINGLE MAGNETIC DOMAINS.
References Cited (Backward Citations)
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Cited
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US2923683A
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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) | 1969-10-10 | 1970-04-11 | 1970-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-10 | 1974-04-11 | 1974-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-10 | 1978-04-11 | 1978-10-11 | $7700.00 | Window Closed / Lapsed |