Patent US3445284A successfully refreshed from Google Patents.
US3445284A
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US
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Process for pickling of steel strip and regeneration of the contact acid
Assignee: Dravo Corp
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Filing: 1965-09-17
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Granted: 1969-05-20
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Expires: 1985-09-17
Abstract
No abstract record available.
Inventors
- 👤 Melville W Robinson Jr
- 👤 Clarence Steelman Jr
- 👤 Enoch Perkins Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:53
CPC Classifications
C; C23; C23G; C23G3/00; C23G3/02; C23G3/021; C01; C01G; C01G49/00; C01G49/02; C01G49/06; C23G1/00; C23G1/36; Y; Y10; Y10S; Y10S423/00; Y10S423/01
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1544506A
Cited
US2428221A
Cited
US2668130A
Cited
US2709143A
Cited
GB838261A
Cited
US3129712A
Cited
US3100727A
Cited
US3310435A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-19 | 1972-11-18 | 1973-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-19 | 1976-11-18 | 1977-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-19 | 1980-11-18 | 1981-05-20 | $7700.00 | Window Closed / Lapsed |