Patent US5206147A successfully refreshed from Google Patents.
US2765331A
Expired / Lapsed
US
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Esters of phosphorus acids and process for the preparation of the same
Assignee: Shell Development Co
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Filing: 1952-02-29
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Granted: 1956-10-02
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Expires: 1972-02-29
Abstract
No abstract record available.
Inventors
- 👤 Richard R Whetstone
- 👤 Harman Denham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:19
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/547; C07F9/6564; C07F9/6571; C07F9/6574; C07F9/65742; C07F9/06; C07F9/08; C07F9/09; C07F9/113
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
11 words
AN ESTER OF H3PO4 HAVING A STRUCTURE REPRESENTED BY THE FORMULA
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-10-02 | 1960-04-02 | 1960-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-02 | 1964-04-02 | 1964-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-02 | 1968-04-02 | 1968-10-02 | $7700.00 | Window Closed / Lapsed |