Patent US2809940A successfully refreshed from Google Patents.
US2809940A
Expired / Lapsed
US
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Method of producing a silver catalyst
Assignee: Napier Turbochargers Ltd
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Filing: 1954-01-12
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Granted: 1957-10-15
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Expires: 1974-01-12
Abstract
No abstract record available.
Inventors
- 👤 Crum John Paterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:35
CPC Classifications
B; B01; B01J; B01J35/00; B01J35/50; B01J35/58; B01J23/00; B01J23/38; B01J23/48; B01J23/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2174840A
Cited
US1671620A
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US2111584A
Cited
US2251913A
Cited
US2404824A
Cited
US2615930A
Cited
US2465773A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-14 | 1961-04-15 | 1961-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-14 | 1965-04-15 | 1965-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-14 | 1969-04-15 | 1969-10-15 | $7700.00 | Window Closed / Lapsed |