US2181890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of salts of interface
Assignee: —
•
Filing: —
•
Granted: 1939-12-05
•
Expires: 1956-12-05
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:21
CPC Classifications
C; C07; C07C; C07C309/00; C07C309/01; C07C309/02; C07C309/03; C07C309/13; C07C309/14; C07C309/15; C07F; C07F5/00; C07F5/02; C07F9/00; C07F9/02; C07F9/28; C07F9/38; C07F9/40
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) | 1942-12-04 | 1943-06-05 | 1943-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-12-04 | 1947-06-05 | 1947-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-12-04 | 1951-06-05 | 1951-12-05 | $7700.00 | Window Closed / Lapsed |