Patent US3784638A successfully refreshed from Google Patents.
US3784638A
Expired / Lapsed
US
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Preparation of tertiary organo-phosphine oxides
Assignee: Polaroid Corp
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Filing: 1969-12-24
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Granted: 1974-01-08
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Expires: 1989-12-24
Abstract
Abstract ORGANOPHOSPHINES ARE CONVERTED TO THEIR FINAL PHOSPHORUS OXIDATION PRODUCTS BY THE ADDITION OF 1, 2 OR 3 ATOM EQUIVALENTS OF OXYGEN BY TREATING THE PRIMARY, SECONDARY OR TERTIARY ORGANOPHOSPHINE STARTING MATERIAL WITH AQUEOUS ALKALI.
Inventors
- 👤 R Lambert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:38
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/50; C07F9/53; C07F9/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |