US2459438A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of hydrofluoric acid
Assignee: Harshaw Chemical Co
•
Filing: 1945-08-23
•
Granted: 1949-01-18
•
Expires: 1965-08-23
Abstract
No abstract record available.
Inventors
- 👤 Harry C Kremers
- 👤 Irwin E Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:59
CPC Classifications
C; C01; C01B; C01B7/00; C01B7/19; C01B7/191
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-01-18 | 1952-07-19 | 1953-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-01-18 | 1956-07-19 | 1957-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-01-18 | 1960-07-19 | 1961-01-18 | $7700.00 | Window Closed / Lapsed |