Patent US4307181A successfully refreshed from Google Patents.
US2428221A
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Pickling process
Assignee: Walker Brothers Co
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Filing: 1942-02-06
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Granted: 1947-09-30
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Expires: 1962-02-06
Abstract
No abstract record available.
Inventors
- 👤 James W Hudson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:09
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/36; C23G3/00; C23G3/02; C23G3/021; Y; Y10; Y10S; Y10S423/00; Y10S423/01
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1146071A
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US1272917A
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GB273307A
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US1853330A
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US2017773A
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US2123434A
Cited
US2193051A
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US2235658A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-09-29 | 1951-03-31 | 1951-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-09-29 | 1955-03-31 | 1955-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-09-29 | 1959-03-31 | 1959-09-30 | $7700.00 | Window Closed / Lapsed |