US2429484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of ketones and ketols by alkali treatment and distillation
Assignee: Shell Development Co
•
Filing: 1943-09-10
•
Granted: 1947-10-21
•
Expires: 1963-09-10
Abstract
No abstract record available.
Inventors
- 👤 Leslie M Peters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:04
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/78; C07C45/85; C07C45/80; C07C45/81; C07C45/82
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-10-20 | 1951-04-21 | 1951-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-10-20 | 1955-04-21 | 1955-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-10-20 | 1959-04-21 | 1959-10-21 | $7700.00 | Window Closed / Lapsed |