US2658078A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solvent extraction of oxytetracycline
Assignee: Pfizer Inc
•
Filing: 1950-09-19
•
Granted: 1953-11-03
•
Expires: 1970-09-19
Abstract
No abstract record available.
Inventors
- 👤 Edwin W Blase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:31
CPC Classifications
C; C07; C07C; C07C233/00; C07C237/00; C07C237/24; C07C237/26; Y; Y10; Y10S; Y10S424/00; Y10S424/06; Y10S435/00; Y10S435/814; Y10S435/816
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
36 words
IN A PROCESS FOR THE SOLVENT-EXTRACTION OF OXYTETRACYCLINE FROM A CLARIFIED, ACIDIC, OXYTETRACYCLINE-CONTAINING FERMENTATION BROTH, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE CLARIFIED BROTH BEFORE THE EXTRACTION AT LEAST ONE SEQUESTERING AGENT FOR POLYVALENT METALLIC IONS.
Claim 2
Dependent Claim
36 words
IN A PROCESS FOR THE SOLVENT-EXTRACTION OF OXYTETRACYCLINE FROM A CLARIFIED, ACIDIC, OXYTETRACYCLINE-CONTAINING FERMENTATION BROTH, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE CLARIFIED BROTH BEFORE THE EXTRACTION AT LEAST ONE SEQUESTERING AGENT FOR POLYVALENT METALLIC IONS.
References Cited (Backward Citations)
US2461922A
Cited
US2516080A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-11-02 | 1957-05-04 | 1957-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-02 | 1961-05-04 | 1961-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-02 | 1965-05-04 | 1965-11-03 | $7700.00 | Window Closed / Lapsed |