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US2428516A
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US
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Process of separating isobutylene from admixture of butene-1 and isobutylene
Assignee: Phillips Petroleum Co
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Filing: 1942-09-24
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Granted: 1947-10-07
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Expires: 1962-09-24
Abstract
No abstract record available.
Inventors
- 👤 Harry E Drennan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:44
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1914674A
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US2199133A
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US2311096A
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US2281804A
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US2282231A
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US2388510A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-10-06 | 1951-04-07 | 1951-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-10-06 | 1955-04-07 | 1955-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-10-06 | 1959-04-07 | 1959-10-07 | $7700.00 | Window Closed / Lapsed |