US1842884A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of purifying sulphuric acid
Assignee: Grasselli Chemical Co
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Filing: 1929-08-31
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Granted: 1932-01-26
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Expires: 1949-08-31
Abstract
No abstract record available.
Inventors
- 👤 Edward A Taylor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:32
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/69; C01B17/90; C01B17/905
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) | 1935-01-25 | 1935-07-27 | 1936-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-01-25 | 1939-07-27 | 1940-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-01-25 | 1943-07-27 | 1944-01-26 | $7700.00 | Window Closed / Lapsed |