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US2439880A
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Tungsten-molybdenum trioxide catalyst
Assignee: EIDP Inc
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Filing: 1942-10-13
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Granted: 1948-04-20
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Expires: 1962-10-13
Abstract
No abstract record available.
Inventors
- 👤 Herrick R Arnold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:50
CPC Classifications
C; C01; C01G; C01G41/00; B; B01; B01J; B01J23/00; B01J23/16; B01J23/24; B01J23/30; C07; C07C; C07C45/00; C07C45/27; C07C45/32; C07C45/37; C07C45/38; C07C45/39
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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AU1732028A
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US2042285A
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GB349444A
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US2002997A
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US1985792A
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FR740445A
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US1998626A
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US2217865A
Cited
US2137275A
Cited
US2198545A
Cited
US2268109A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-04-20 | 1951-10-20 | 1952-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-04-20 | 1955-10-20 | 1956-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-04-20 | 1959-10-20 | 1960-04-20 | $7700.00 | Window Closed / Lapsed |