US2499385A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for defluorinating phosphate rock
Assignee: Tennessee Valley Authority
•
Filing: 1947-11-29
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Granted: 1950-03-07
•
Expires: 1967-11-29
Abstract
No abstract record available.
Inventors
- 👤 Theodore N Hubbuch
- 👤 Travis P Hignett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:23
CPC Classifications
C; C05; C05B; C05B13/00; C05B13/02; Y; Y10; Y10S; Y10S71/00; Y10S71/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
32 words
IN A PROCESS FOR DEFLUORINATING PHOSPHATE ROCK WHEREIN A CHARGE CONSISTING OF PHOSPHATE ROCK AND SILICA IN WHICH THE PROPORTION OF SILICA IS IN EXCESS OF THAT REQUIRED TO SATISFY THE EQUATION.
Claim 2
Dependent Claim
32 words
IN A PROCESS FOR DEFLUORINATING PHOSPHATE ROCK WHEREIN A CHARGE CONSISTING OF PHOSPHATE ROCK AND SILICA IN WHICH THE PROPORTION OF SILICA IS IN EXCESS OF THAT REQUIRED TO SATISFY THE EQUATION.
References Cited (Backward Citations)
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US1260660A
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US1411696A
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US1803417A
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US2189248A
Cited
US2220575A
Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-03-06 | 1953-09-05 | 1954-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-03-06 | 1957-09-05 | 1958-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-03-06 | 1961-09-05 | 1962-03-07 | $7700.00 | Window Closed / Lapsed |