US2858229A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of spinning solutions
Assignee: —
•
Filing: —
•
Granted: 1958-10-28
•
Expires: 1975-10-28
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:50
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C08J3/091
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
118 words
PROCESS FOR THE PREPARATION OF CONCENTRATED SOLUTIONS OF CELLULOSE ACETATE HAVING AN ACETYL VALUE OF ABOVE ABOUT 58% BY WEIGHT DISSOLVED IN A SOLVENT, WHICH COMPRISES FORMING A SOLUTION HAVING CONCENTRATION OF LESS THAN ABOUT 19% BY WEIGHT OF THE CELLULOSE ACETATE IN A SOLUVENT OF THE CLASS CONSISTING OF METHYLENE CHLORIDE AND MIXTURES OF METHYLENE CHLORIDE AND LOWER ALIPHATIC ALCOHOLS, AND REMOVING SOLVENT FROM SAID SOLUTION UNTIL THE CONCENTRATION OF THE CELLULOSE ACETATE IN SAID SOLUTION IS AT THE DESIRED VALUE ABOVE ABOUT 20% BY WEIGHT TO FORM A CONCENTRATED CELLULOSE ACETATE SOLUTION OF IMPROVED FILTERABILITY AND SPINNING STABILITY, AS COMPARED WITH A SOLUTION OF THE SAME HIGH CONCENTRATION PREPARED BY DIRECT DISSOLVING AT SAID HIGH CONCENTRATION.
Claim 2
Dependent Claim
118 words
PROCESS FOR THE PREPARATION OF CONCENTRATED SOLUTIONS OF CELLULOSE ACETATE HAVING AN ACETYL VALUE OF ABOVE ABOUT 58% BY WEIGHT DISSOLVED IN A SOLVENT, WHICH COMPRISES FORMING A SOLUTION HAVING CONCENTRATION OF LESS THAN ABOUT 19% BY WEIGHT OF THE CELLULOSE ACETATE IN A SOLUVENT OF THE CLASS CONSISTING OF METHYLENE CHLORIDE AND MIXTURES OF METHYLENE CHLORIDE AND LOWER ALIPHATIC ALCOHOLS, AND REMOVING SOLVENT FROM SAID SOLUTION UNTIL THE CONCENTRATION OF THE CELLULOSE ACETATE IN SAID SOLUTION IS AT THE DESIRED VALUE ABOVE ABOUT 20% BY WEIGHT TO FORM A CONCENTRATED CELLULOSE ACETATE SOLUTION OF IMPROVED FILTERABILITY AND SPINNING STABILITY, AS COMPARED WITH A SOLUTION OF THE SAME HIGH CONCENTRATION PREPARED BY DIRECT DISSOLVING AT SAID HIGH CONCENTRATION.
References Cited (Backward Citations)
GB285829A
Cited
US1762937A
Cited
GB323031A
Cited
US1831795A
Cited
US2045161A
Cited
US2319055A
Cited
US2492977A
Cited
US2697251A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-10-27 | 1962-04-28 | 1962-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-27 | 1966-04-28 | 1966-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-27 | 1970-04-28 | 1970-10-28 | $7700.00 | Window Closed / Lapsed |