US3003967A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for increasing the effective permeability of manganese ferrites
Assignee: Kearfott Co Inc
•
Filing: 1959-09-23
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Granted: 1961-10-10
•
Expires: 1979-09-23
Abstract
No abstract record available.
Inventors
- 👤 Lynn J Brady
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:31
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/26
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
77 words
A METHOD FOR REMOVING THE OXIDE COATING ON A MANGANESE FERRITE COMPOSED OF MANGANESE OXIDE, ZINC OXIDE AND IRON OXIDE TO EFFECT AN INCREASE IN THE PERMEABILITY THEREOF, COMPRISING THE STEPS OF INSERTING AND FERRITE IN AN ACID SOLUTION COMPOSED OF ABOUT TWO VOLUMES OF CONCENTRATED NITRIC ACID, MAINTAINING SAID FERRITE IN SAID CONCENTRATED NITRIC ACID, MAINTAINING SAID FERRITE IN SAID SOLUTION FOR ABOUT ONE HOUR AT ROOM TEMPERATURE, AND THEN REMOVING SAID FERRITE FROM SAID SOLUTION.
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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) | 1964-10-09 | 1965-04-10 | 1965-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-10-09 | 1969-04-10 | 1969-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-10-09 | 1973-04-10 | 1973-10-10 | $7700.00 | Window Closed / Lapsed |