US2398485A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of dicarboxylic acids
Assignee: Shell Development Co
•
Filing: 1943-05-03
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Granted: 1946-04-16
•
Expires: 1963-05-03
Abstract
No abstract record available.
Inventors
- 👤 Norman B Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:33
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10; C23F11/12; C23F11/124; C23F11/126; C07; C07C; C07C51/00; C07C51/42; C07C51/487
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) | 1949-04-15 | 1949-10-15 | 1950-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1953-04-15 | 1953-10-15 | 1954-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1957-04-15 | 1957-10-15 | 1958-04-16 | $7700.00 | Window Closed / Lapsed |