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US2444893A
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US
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Recovery of methyl ethyl ketone from azeotropic distillates by extraction with tetraethylene glycol
Assignee: Union Oil Company of California
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Filing: 1941-10-18
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Granted: 1948-07-06
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Expires: 1961-10-18
Abstract
No abstract record available.
Inventors
- 👤 George R Lake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:58
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/06; C07C45/00; C07C45/78; C07C45/80
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1079004A
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US1866800A
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US2085546A
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US2333856A
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US2212810A
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US2370063A
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US2265220A
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US2290636A
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US2360655A
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US2388040A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-07-06 | 1952-01-05 | 1952-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-07-06 | 1956-01-05 | 1956-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-07-06 | 1960-01-05 | 1960-07-06 | $7700.00 | Window Closed / Lapsed |