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US3544591A
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Preparation of 2,4-bis(hexafluoroisopropylidene) - 1,3 - dithietane and fluorinated polysulfides by reaction of perfluoroisobutene with an alkali metal sulfide
Assignee: EIDP Inc
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Filing: 1967-08-21
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Granted: 1970-12-01
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Expires: 1987-08-21
Abstract
No abstract record available.
Inventors
- 👤 David C England
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:08
CPC Classifications
C; C07; C07D; C07D339/00; C07C; C07C323/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3008966A
Cited
US2970173A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-30 | 1974-06-01 | 1974-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-30 | 1978-06-01 | 1978-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-30 | 1982-06-01 | 1982-12-01 | $7700.00 | Window Closed / Lapsed |