US2521916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of organic acid esters of cellulose
Assignee: Eastman Kodak Co
•
Filing: 1946-11-23
•
Granted: 1950-09-12
•
Expires: 1966-11-23
Abstract
No abstract record available.
Inventors
- 👤 William B Hincke
- 👤 Carl J Malm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:39
CPC Classifications
C; C08; C08B; C08B17/00; C08B17/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
A PROCESS FOR PREPARING LOWER FATTY ACID ESTERS OF CELLULOSE WHICH COMPRISES MIXING CELLULOSE AND AN ESTERIFICATION MIXTURE ESSENTIALLY CONSISTING OF LOWER FATTY ACID ANHYDRIDE, ACYLATION CATALYST, AND A SOLVENT, IN AN ESTERIFICATION MIXER WHILE THE MIXER BLADES AND WALLS ARE COOLED, UNTIL THE CELLULOSE STARTS TO GO INTO SOLUTION, THEN WHILE CONTINUING THE MIXING WITH THE COOLED MIXER BLADES IMPARTING TO THE WALLS OF THE MIXER CONTACTED BY THE CELLULOSE ESTER SOLUTION, A TEMPERATURE OF 80-130*F. UNTIL THE ESTERIFICATION IS COMPLETED.
Claim 2
Dependent Claim
82 words
A PROCESS FOR PREPARING LOWER FATTY ACID ESTERS OF CELLULOSE WHICH COMPRISES MIXING CELLULOSE AND AN ESTERIFICATION MIXTURE ESSENTIALLY CONSISTING OF LOWER FATTY ACID ANHYDRIDE, ACYLATION CATALYST, AND A SOLVENT, IN AN ESTERIFICATION MIXER WHILE THE MIXER BLADES AND WALLS ARE COOLED, UNTIL THE CELLULOSE STARTS TO GO INTO SOLUTION, THEN WHILE CONTINUING THE MIXING WITH THE COOLED MIXER BLADES IMPARTING TO THE WALLS OF THE MIXER CONTACTED BY THE CELLULOSE ESTER SOLUTION, A TEMPERATURE OF 80-130*F. UNTIL THE ESTERIFICATION IS COMPLETED.
References Cited (Backward Citations)
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Cited
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US1829822A
Cited
US1854732A
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US2345406A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |