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US2954303A Expired / Lapsed US ⏱️ 0.0 years remaining

Production of ferromagnetic oxide

Assignee: American Pigment Corp
•
Filing: 1956-04-17
•
Granted: 1960-09-27
•
Expires: 1976-04-17
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Abstract

No abstract record available.

Inventors

  • 👤 Westcott Horace Clifford

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 13:25
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70642; G11B5/70678; G11B5/70684; G11B5/70689; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31826; Y10T428/31833; Y10T428/31855; Y10T428/31935

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 113 words
A MAGNETIC RECORD MEMBER HAVING A NON-MAGNETIC CARRIER AND A MAGNETIC TRACK ADHERENTLY BONDED THERETO OF MAGNETIC MATERIAL AND BINDER COMPOSITION, SAID MAGNETIC MATERIAL HAVING A COERCIVITY OF NOT GREATER THAN ABOUT 300 OERSTEDS AND COMPRISING GROUND PARTICLES OF AT LEAST ONE MAGNETICALLY ANISOTROPIC, GASEOUSLY REDUCED SYNTHETIC IRON OXIDE SELECTED FROM THE GROUP CONSISTING OF FERROSOFERRIC OXIDE FE2O3FEO AND GAMMA FERRIC OXIDE FE2O3, SAID IRON OXIDE HAVING BEEN GROUND UNDER NONAQUEOUS CONDITIONS TO SUCH FINE SIZE AND SMOOTH SURFACE AS TO HAVE AN OIL ABSORPTION CHARACTERISTIC NOT GREATER THAN ABOUT 0.45 ML. OF OIL PER GRAM OF OXIDE, AND BEING CAPABLE UPON ORIENTATION OF YIELDING A BR/BS VALUE RANGING FROM 0.5 TO 0.9.
Claim 2
Dependent Claim 113 words
A MAGNETIC RECORD MEMBER HAVING A NON-MAGNETIC CARRIER AND A MAGNETIC TRACK ADHERENTLY BONDED THERETO OF MAGNETIC MATERIAL AND BINDER COMPOSITION, SAID MAGNETIC MATERIAL HAVING A COERCIVITY OF NOT GREATER THAN ABOUT 300 OERSTEDS AND COMPRISING GROUND PARTICLES OF AT LEAST ONE MAGNETICALLY ANISOTROPIC, GASEOUSLY REDUCED SYNTHETIC IRON OXIDE SELECTED FROM THE GROUP CONSISTING OF FERROSOFERRIC OXIDE FE2O3FEO AND GAMMA FERRIC OXIDE FE2O3, SAID IRON OXIDE HAVING BEEN GROUND UNDER NONAQUEOUS CONDITIONS TO SUCH FINE SIZE AND SMOOTH SURFACE AS TO HAVE AN OIL ABSORPTION CHARACTERISTIC NOT GREATER THAN ABOUT 0.45 ML. OF OIL PER GRAM OF OXIDE, AND BEING CAPABLE UPON ORIENTATION OF YIELDING A BR/BS VALUE RANGING FROM 0.5 TO 0.9.

References Cited (Backward Citations)

US1575717A Cited
US2441613A Cited
US2694656A Cited
US2689168A Cited
US2643130A Cited
US2719009A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1963-09-27 1964-03-28 1964-09-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1967-09-27 1968-03-28 1968-09-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1971-09-27 1972-03-28 1972-09-27 $7700.00 Window Closed / Lapsed

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