US2861038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dewatering cellulose ester composition
Assignee: Celanese Corp
•
Filing: 1955-03-03
•
Granted: 1958-11-18
•
Expires: 1975-03-03
Abstract
No abstract record available.
Inventors
- 👤 Henry W Steinmann
- 👤 Dunay Michael
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:52
CPC Classifications
C; C08; C08B; C08B3/00; C08B3/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
89 words
IN A PROCESS WHEREIN A SOLUTION OF AN ORGANIC ACID ESTER OF CELLULOSE IN A WATER IMMISCIBLE SOLVENT COMPRISING METHYLENE CHLORIDE IS SUBJECTED TO A TWO-PHASE EXFRACTION WITH AN AQUEOUS MATERIAL AND WHEREIN THERE IS RECOVERED FROM SAID EXTRACTION AN EXTRACTED SOLUTION FREE FROM IMPURITIES BUT CONTAINING A SMALL PERCENTAGE OF WATER, THE IMPROVEMENT WHICH COMPRISES DEWATERING SAID SOLUTION BY BRINGING IT INTO CONTACT WITH A SEMI-PERMEABLE MEMBRANE THROUGH WHICH WATER ALONE CAN PASS AND REMOVING FROM THE OTHER SURFACE OF SAID MEMBRANE THE WATER THAT HAS PASSED THERETHROUGH.
Claim 2
Dependent Claim
89 words
IN A PROCESS WHEREIN A SOLUTION OF AN ORGANIC ACID ESTER OF CELLULOSE IN A WATER IMMISCIBLE SOLVENT COMPRISING METHYLENE CHLORIDE IS SUBJECTED TO A TWO-PHASE EXFRACTION WITH AN AQUEOUS MATERIAL AND WHEREIN THERE IS RECOVERED FROM SAID EXTRACTION AN EXTRACTED SOLUTION FREE FROM IMPURITIES BUT CONTAINING A SMALL PERCENTAGE OF WATER, THE IMPROVEMENT WHICH COMPRISES DEWATERING SAID SOLUTION BY BRINGING IT INTO CONTACT WITH A SEMI-PERMEABLE MEMBRANE THROUGH WHICH WATER ALONE CAN PASS AND REMOVING FROM THE OTHER SURFACE OF SAID MEMBRANE THE WATER THAT HAS PASSED THERETHROUGH.
References Cited (Backward Citations)
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-11-17 | 1962-05-19 | 1962-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-11-17 | 1966-05-19 | 1966-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-11-17 | 1970-05-19 | 1970-11-18 | $7700.00 | Window Closed / Lapsed |