US1751955A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of active silica
Assignee: IG Farbenindustrie AG
•
Filing: 1926-07-16
•
Granted: 1930-03-25
•
Expires: 1946-07-16
Abstract
No abstract record available.
Inventors
- 👤 Stoewener Fritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:58
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/18; C01B33/187; C01B33/193
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1933-03-24 | 1933-09-23 | 1934-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-03-24 | 1937-09-23 | 1938-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-03-24 | 1941-09-23 | 1942-03-25 | $7700.00 | Window Closed / Lapsed |