US1944903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of naphthalene and gumforming constituents from gas
Assignee: Koppers Co of Delaware
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Filing: 1930-07-22
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Granted: 1934-01-30
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Expires: 1950-07-22
Abstract
No abstract record available.
Inventors
- 👤 Alfred R Powell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:42
CPC Classifications
C; C10; C10K; C10K1/00; C10K1/08; C10K1/16; C10K1/18
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) | 1937-01-29 | 1937-07-31 | 1938-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1941-01-29 | 1941-07-31 | 1942-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1945-01-29 | 1945-07-31 | 1946-01-30 | $7700.00 | Window Closed / Lapsed |