Patent US2487820A successfully refreshed from Google Patents.
US2487820A
Expired / Lapsed
US
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Fluorination of fused-ring hydrocarbons with lead tetrafluoride
Assignee: Purdue Research Foundation
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Filing: 1945-12-15
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Granted: 1949-11-15
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Expires: 1965-12-15
Abstract
No abstract record available.
Inventors
- 👤 Earl T Mcbee
- 👤 Richard M Robb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:37
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/013; C07C17/06; C07C17/093; C07C17/10; C07C17/12; C07C2603/00; C07C2603/02; C07C2603/04; C07C2603/22; C07C2603/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB214293A
Cited
US2024008A
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US2004932A
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GB429591A
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US2013035A
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FR786123A
Cited
US2062743A
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US2220713A
Cited
US2192143A
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US2238242A
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US2426172A
Cited
US2423045A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-11-14 | 1953-05-16 | 1953-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-11-14 | 1957-05-16 | 1957-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-11-14 | 1961-05-16 | 1961-11-15 | $7700.00 | Window Closed / Lapsed |