US2803651A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of isolation of choline salts
Assignee: Wyeth Holdings LLC
•
Filing: 1955-01-06
•
Granted: 1957-08-20
•
Expires: 1975-01-06
Abstract
No abstract record available.
Inventors
- 👤 Earl R Whiston
- 👤 Hal E Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:07
CPC Classifications
C; C07; C07C; C07C43/00; C07C43/30; C07C43/315; C07C213/00; C07C213/10; C07C215/00; C07C215/02; C07C215/40
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
IN THE PROCESS OF RECOVERING CHOLINE SALTS SELECTED FROM THE GROUP CONSISTING OF CHOLINE DIHYDROGEN CITRATE, CHOLINE PHOSPHATE, AND DICHOLINE MUCATE BY CRYSTALLIZATION FROM METHANOLIC SOLUTIONS THEREOF, THE IMPROVEMENT WHICH COMPRISES ADDING FROM ABOUT 25% TO ABOUT 50% ISOPROPANOL BY VOLUME TO THE METHANOLIC SOLUTION.
Claim 2
Dependent Claim
45 words
IN THE PROCESS OF RECOVERING CHOLINE SALTS SELECTED FROM THE GROUP CONSISTING OF CHOLINE DIHYDROGEN CITRATE, CHOLINE PHOSPHATE, AND DICHOLINE MUCATE BY CRYSTALLIZATION FROM METHANOLIC SOLUTIONS THEREOF, THE IMPROVEMENT WHICH COMPRISES ADDING FROM ABOUT 25% TO ABOUT 50% ISOPROPANOL BY VOLUME TO THE METHANOLIC SOLUTION.
References Cited (Backward Citations)
US2623901A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-08-19 | 1961-02-18 | 1961-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-08-19 | 1965-02-18 | 1965-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-08-19 | 1969-02-18 | 1969-08-20 | $7700.00 | Window Closed / Lapsed |