US2444893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of methyl ethyl ketone from azeotropic distillates by extraction with tetraethylene glycol
Assignee: Union Oil Company of California
•
Filing: 1941-10-18
•
Granted: 1948-07-06
•
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 08:59
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/06; C07C45/00; C07C45/78; C07C45/80
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1079004A
Cited
US1866800A
Cited
US2085546A
Cited
US2333856A
Cited
US2212810A
Cited
US2370063A
Cited
US2265220A
Cited
US2290636A
Cited
US2360655A
Cited
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 |