Patent US3538744A successfully refreshed from Google Patents.
US3538744A
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US
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Chromatography apparatus
Assignee: Phillips Petroleum Co
•
Filing: 1967-11-09
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Granted: 1970-11-10
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Expires: 1987-11-09
Abstract
No abstract record available.
Inventors
- 👤 Francis W Karasek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:50
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/60; G01N30/6095; G01N30/90; G01N30/92
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2920478A
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US3149941A
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DE1113319B
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US3143404A
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US3254479A
Cited
US3273377A
Cited
US3307333A
Cited
US3263493A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-09 | 1974-05-11 | 1974-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-09 | 1978-05-11 | 1978-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-09 | 1982-05-11 | 1982-11-10 | $7700.00 | Window Closed / Lapsed |