Patent US2249816A successfully refreshed from Google Patents.
US2249816A
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US
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Separation of amines
Assignee: Sharples Chemicals Inc
•
Filing: 1938-11-08
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Granted: 1941-07-22
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Expires: 1958-11-08
Abstract
No abstract record available.
Inventors
- 👤 Thomas E Deger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:35
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/06
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) | 1944-07-21 | 1945-01-20 | 1945-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-07-21 | 1949-01-20 | 1949-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-07-21 | 1953-01-20 | 1953-07-22 | $7700.00 | Window Closed / Lapsed |