US2623844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extractive distillation of isoprene with dimethyl sulfolane
Assignee: Standard Oil Development Co
•
Filing: 1947-07-29
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Granted: 1952-12-30
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Expires: 1967-07-29
Abstract
No abstract record available.
Inventors
- 👤 Harold W Scheeline
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:57
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/005; C07C7/04; C07C7/05; C07C7/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2426705A
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US2360861A
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US2360859A
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US2455803A
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US2434706A
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US2534013A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-30 | 1956-06-30 | 1956-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-30 | 1960-06-30 | 1960-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-30 | 1964-06-30 | 1964-12-30 | $7700.00 | Window Closed / Lapsed |