Patent US2861038A successfully refreshed from Google Patents.
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 16:44
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)
US2126190A
Cited
US1573673A
Cited
US1885393A
Cited
US2114491A
Cited
US2386826A
Cited
US2386381A
Cited
GB696903A
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 |