Patent US2819320A successfully refreshed from Google Patents.
US2819320A
Expired / Lapsed
US
⏱️ 0.0 years remaining
1, 1, 2, 2-tetrafluorocycloheptadienes
Assignee: EIDP Inc
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Filing: 1956-02-09
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Granted: 1958-01-07
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Expires: 1976-02-09
Abstract
No abstract record available.
Inventors
- 👤 John J Drysdale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:38
CPC Classifications
C; C07; C07C; C07C23/00; C07C23/02; C07C23/14; C07C17/00; C07C17/35; C07C17/358
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
13 words
A 1,1,2,2-TETRAFLUOROCYCLOHEPTADIENE, C7,H6,F4, HAVING HYDROGEN ON EACH CARBON OTHER THAN THE FLUORINE-BEARING CARBONS.
Claim 2
Dependent Claim
13 words
A 1,1,2,2-TETRAFLUOROCYCLOHEPTADIENE, C7,H6,F4, HAVING HYDROGEN ON EACH CARBON OTHER THAN THE FLUORINE-BEARING CARBONS.
Claim 3
Dependent Claim
16 words
THE PROCESS WHICH COMPRISES PYROLYZING 6,6,7,7-TETRAFLUOROBICYCLO(3.2.0)-HEPT-2-ENE AT 600-750*C. AT REDUCED PRESSURE AND ISOLATING THE 1,1,2,2-TETRAFLUOROCYCLOHEPTADIENES OBTAINED.
Claim 4
Dependent Claim
16 words
THE PROCESS WHICH COMPRISES PYROLYZING 6,6,7,7-TETRAFLUOROBICYCLO(3.2.0)-HEPT-2-ENE AT 600-750*C. AT REDUCED PRESSURE AND ISOLATING THE 1,1,2,2-TETRAFLUOROCYCLOHEPTADIENES OBTAINED.
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) | 1961-01-06 | 1961-07-08 | 1962-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-06 | 1965-07-08 | 1966-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-06 | 1969-07-08 | 1970-01-07 | $7700.00 | Window Closed / Lapsed |