Patent US3642631A successfully refreshed from Google Patents.
US3642631A
Expired / Lapsed
US
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Surstituted bithiophenes
Assignee: United States Department of the Army
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Filing: 1970-11-24
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Granted: 1972-02-15
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Expires: 1990-11-24
Abstract
Abstract A NEW HEAT-STABLE COMPOUND, 5,5''-DIHEPTAFLUOBUTYRYL2,2''-BITHIOPHENE, AND METHODS FOR ITS PREPARATION WHICH INVOLVES THE USE OF ETHYL BROMIDE IN AN UCATALYZED GRIGNARD COUPLING REACTION, AS WELL AS METHODS FOR PREPARING OTHER RELATED BITHIOPHENES HAVING AT LEAST ONE SUBSTITUENT IN EACH THIOPHENE RING. LUBRICATING OILS AND HYDRAULIC FLUIDS CONTAINING THIS COMPOUND AS A FRICTION REDUCING AGENT ARE ALSO DESCRIBED.
Inventors
- 👤 Henry Gisser
- 👤 Seymour Portnoy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:48
CPC Classifications
C; C10; C10M; C10M3/00; C07; C07D; C07D333/00; C07D333/02; C07D333/04; C07D333/26; C07D333/28; C10M2207/00; C10M2207/28; C10M2207/282; C10M2207/34; C10M2219/00; C10M2219/10; C10M2219/102; C10M2219/104; C10M2219/106; C10N; C10N2030/00; C10N2030/08; C10N2040/00; C10N2040/08; C10N2040/12; C10N2040/13
Claims Analysis
Total Claims: 0
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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) | 1975-02-14 | 1975-08-16 | 1976-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-14 | 1979-08-16 | 1980-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-14 | 1983-08-16 | 1984-02-15 | $7700.00 | Window Closed / Lapsed |