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Patent US2456561A successfully refreshed from Google Patents.
US2456561A
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Azeotropic separation of xylene isomers
Assignee: Union Oil Company of California
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Filing: 1943-03-27
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Granted: 1948-12-14
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Expires: 1963-03-27
Abstract
No abstract record available.
Inventors
- 👤 George R Lake
- 👤 Josephine M Mcdowell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:39
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)
US2279779A
Cited
US2279780A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-12-14 | 1952-06-14 | 1952-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-14 | 1956-06-14 | 1956-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-14 | 1960-06-14 | 1960-12-14 | $7700.00 | Window Closed / Lapsed |