US2071987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicic acid gels
Assignee: EIDP Inc
•
Filing: 1933-12-01
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Granted: 1937-02-23
•
Expires: 1953-12-01
Abstract
No abstract record available.
Inventors
- 👤 Earl S Ridler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:09
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/14; C01B33/157
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) | 1940-02-23 | 1940-08-24 | 1941-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-02-23 | 1944-08-24 | 1945-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-02-23 | 1948-08-24 | 1949-02-23 | $7700.00 | Window Closed / Lapsed |