US2833628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of silicon tetrafluoride
Assignee: WR Grace and Co
•
Filing: 1954-06-09
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Granted: 1958-05-06
•
Expires: 1974-06-09
Abstract
No abstract record available.
Inventors
- 👤 Melvin C Molstad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:37
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
89 words
A PROCESS FOR PREPARING SUBSTANTIALLY PURE SILICON TETRAFLUORIDE WHICH COMPRISES PROVIDING A BODY OF SULFURIC ACID STRONGER THAN 70% BY WEIGHT H2SO4, CONTINUOUSLY INTRODUCING TO SAID BODY FLUOSILICIC ACID, MAINTAINING AT ALL TIMES A QUANTITY OF SILICA IN SAID BODY OF SULFURIC ACID AT LEAST SUFFICIENT TO REACT COMPLETELY WITH THE FLUOSILICIC ACID ADDED, CONTINUOUSLY FEEDING SULFURIC ACID TO SAID BODY TO MAINTAIN ITS CONCENTRATION ABOVE 70% AND WITHDRAWING SULFURIC ACID OF A CONCENTRATION NOT LESS THAN ABOUT 70% BY WEIGHT H2SO4, AND CONTINUOUSLY REMOVING SUBSTANTIALLY PURE SILICON TETRAFLUORIDE.
Claim 2
Dependent Claim
89 words
A PROCESS FOR PREPARING SUBSTANTIALLY PURE SILICON TETRAFLUORIDE WHICH COMPRISES PROVIDING A BODY OF SULFURIC ACID STRONGER THAN 70% BY WEIGHT H2SO4, CONTINUOUSLY INTRODUCING TO SAID BODY FLUOSILICIC ACID, MAINTAINING AT ALL TIMES A QUANTITY OF SILICA IN SAID BODY OF SULFURIC ACID AT LEAST SUFFICIENT TO REACT COMPLETELY WITH THE FLUOSILICIC ACID ADDED, CONTINUOUSLY FEEDING SULFURIC ACID TO SAID BODY TO MAINTAIN ITS CONCENTRATION ABOVE 70% AND WITHDRAWING SULFURIC ACID OF A CONCENTRATION NOT LESS THAN ABOUT 70% BY WEIGHT H2SO4, AND CONTINUOUSLY REMOVING SUBSTANTIALLY PURE SILICON TETRAFLUORIDE.
References Cited (Backward Citations)
US1994070A
Cited
US2504446A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-05-05 | 1961-11-04 | 1962-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-05-05 | 1965-11-04 | 1966-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-05-05 | 1969-11-04 | 1970-05-06 | $7700.00 | Window Closed / Lapsed |