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Patent US2390934A successfully refreshed from Google Patents.
US2390934A
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Method of separating butadiene and butylene from hydrocarbon mixtures
Assignee: Dow Chemical Co
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Filing: 1941-03-03
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Granted: 1945-12-11
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Expires: 1961-03-03
Abstract
No abstract record available.
Inventors
- 👤 Charles L Gregg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:17
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) | 1948-12-10 | 1949-06-11 | 1949-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1952-12-10 | 1953-06-11 | 1953-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1956-12-10 | 1957-06-11 | 1957-12-11 | $7700.00 | Window Closed / Lapsed |