Patent US3490872A successfully refreshed from Google Patents.
US3490872A
Expired / Lapsed
US
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Production of hydrogen from carbon monoxide and water in alkaline solutions
Assignee: Union Oil Company of California
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Filing: 1967-08-29
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Granted: 1970-01-20
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Expires: 1987-08-29
Abstract
No abstract record available.
Inventors
- 👤 Donald M Fenton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:50
CPC Classifications
C; C01; C01B; C01B3/00; C01B3/02; C01B3/06; C01B3/12; C01B3/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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GB586758A
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US2960388A
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US3259523A
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US3290406A
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US3251652A
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US3278268A
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US3254956A
Cited
US3350176A
Cited
US3382045A
Cited
US3355249A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-01-19 | 1973-07-21 | 1974-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-01-19 | 1977-07-21 | 1978-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-01-19 | 1981-07-21 | 1982-01-20 | $7700.00 | Window Closed / Lapsed |