Patent EP0235365A2 successfully refreshed from Google Patents.
Patent US2718456A successfully refreshed from Google Patents.
US2718456A
Expired / Lapsed
US
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Hexafluorophosphoric acid compositions and preparation thereof
Assignee: Shell Development Co
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Filing: 1952-03-17
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Granted: 1955-09-20
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Expires: 1972-03-17
Abstract
No abstract record available.
Inventors
- 👤 Albertus J Mulder
- 👤 Smithuysen Willem Brezesinska
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:29
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
24 words
A PROCESS FOR THE PREPARATION OF ANHYDROUS HEXAFLUOROPHOSPHORIC ACID, WHICH COMPRISES EFFECTING REATION OF HYDROGEN FLUORIDE WITH PHOSPHOROUS PENTAFLUORIDE IN ANHYDROUS LIQUID SULFUR DIOXIDE.
Claim 2
Dependent Claim
24 words
A PROCESS FOR THE PREPARATION OF ANHYDROUS HEXAFLUOROPHOSPHORIC ACID, WHICH COMPRISES EFFECTING REATION OF HYDROGEN FLUORIDE WITH PHOSPHOROUS PENTAFLUORIDE IN ANHYDROUS LIQUID SULFUR DIOXIDE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-09-19 | 1959-03-21 | 1959-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-09-19 | 1963-03-21 | 1963-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-09-19 | 1967-03-21 | 1967-09-20 | $7700.00 | Window Closed / Lapsed |