Patent US2685941A successfully refreshed from Google Patents.
US2685941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for concentrating hydrogen
Assignee: Universal Oil Products Co
•
Filing: 1951-01-31
•
Granted: 1954-08-10
•
Expires: 1971-01-31
Abstract
No abstract record available.
Inventors
- 👤 Louis S Kassel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:37
CPC Classifications
C; C01; C01B; C01B3/00; C01B3/50; C01B3/52; C01B2203/00; C01B2203/04; C01B2203/0415; C01B2203/0465; C01B2203/048
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1869825A
Cited
US2074644A
Cited
US2299830A
Cited
US2337254A
Cited
US2468750A
Cited
US2428521A
Cited
US2495842A
Cited
US2523747A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-08-09 | 1958-02-08 | 1958-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-08-09 | 1962-02-08 | 1962-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-08-09 | 1966-02-08 | 1966-08-10 | $7700.00 | Window Closed / Lapsed |