Patent US3637842A successfully refreshed from Google Patents.
US3637842A
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Perfluoro polyether acyl fluorides
Assignee: National Aeronautics and Space Administration
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Filing: 1968-10-24
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Granted: 1972-01-25
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Expires: 1988-10-24
Abstract
Abstract PERFLUORO POLYETHERS HAVING THE FORMULA: X(CF(CF3)O(CF2)POCF(CF3))NX WHERE N IS AN INTEGER OF FROM 2 TO 12, P IS AN INTEGER OF FROM 2 TO 23, AND X IS SELECTED FROM THE GROUP CONSISTING OF F-CO- AND -CH2-OH
Inventors
- 👤 Eugene C Stump
- 👤 Stephen Eugene Rochow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:57
CPC Classifications
C; C07; C07C; C07C43/00; C07C43/02; C07C43/03; C07C43/04; C07C43/13; C07C43/137; C07C59/00; C07C59/235; C07C59/305; C07C59/315
Claims Analysis
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |