Patent US3723485A successfully refreshed from Google Patents.
US3723485A
Expired / Lapsed
US
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Preparation of perfluoroacyl fluorides and perfluorocarboxylic acids
Assignee: 3M Co
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Filing: 1970-02-20
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Granted: 1973-03-27
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Expires: 1990-02-20
Abstract
Abstract Pyrolysis of perfluoroalkanesulfonate salts of yttrium, scandium and rare earth metals in an inert atmosphere provides acyl fluorides when anhydrous salts are employed and carboxylic acids when the hydrated salts are employed. The acyl fluorides and carboxylic acids are useful intermediates known and used in the art.
Inventors
- 👤 K Thom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:37
CPC Classifications
C; C07; C07C; C07C53/00; C07C53/15; C07C53/19; C07C53/21; C07C53/38; C07C53/46; C07C53/50; C22; C22B; C22B59/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
18 words
The process of claim 1 wherein the salts are hydrated and carboxylic acids are recovered from the condensate.
Claim 2
Dependent Claim
21 words
The process of claim 1 wherein the salts are essentially anhydrous and the carboxylic acid fluorides are recovered from the condensate.
Claim 3
Dependent Claim
14 words
The process according to claim 1 wherein Rf is a perfluoroalkane group CnF2n 1.
References Cited (Backward Citations)
US2765326A
Cited
US3254107A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |