US2828303A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mixed cellulose esters containing isobutyryl groups
Assignee: Eastman Kodak Co
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Filing: 1954-06-07
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Granted: 1958-03-25
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Expires: 1974-06-07
Abstract
No abstract record available.
Inventors
- 👤 Carl J Malm
- 👤 Jr Loring W Blanchard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:43
CPC Classifications
C; C08; C08B; C08B3/00; C08B3/16; C08B3/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
122 words
A PROCESS FOR PREPARING MIXED LOWER FATTY ACID ESTERS OF CELLULOSE CONTAINING ISOBUTYRYL GROUPS WHICH COMPRISES INITIALLY REACTING UPON CELLULOSE HAVING AN ACTIVATION VALUE OF AT LEAST 0.2 WITH AN ESTERIFICATION BATH ESSENTIALLY CONSISTING OF ISOBUTYRIC ANHYDRIDE AND ZINC CHLORIDE CATALYST WHICH BATH IS SUBSTANTIALLY FREE OF ACYLS OTHER THAN ISOBUTYRYL AT A TEMPERATURE WITHIN THE RANGE OF 100-150*F.; AND AFTER A SUBSTANTIAL ISOBUTYRYL CONTENT HAS BEEN IMPARTED TO THE CELLULOSE ADDING ADDITIONALLY TO THE ESTERIFICATION BATH A LOWER FATTY ACID COMPOUND SELECTED FROM THE ANHYDRIDES AND ACIDS OF THE FATTY ACIDS OF 2-4 CARBON ATOMS IN AN AMOUNT 5-20% OF THE BATH AND CONTINUING THE ESTERFICATION UNTIL THE CELLULOSE HAS BEEN SUBSTANTIALLY, COMPLETELY ESTERIFIED AND IS IN SOLUTION IN THE BATH.
Claim 2
Dependent Claim
122 words
A PROCESS FOR PREPARING MIXED LOWER FATTY ACID ESTERS OF CELLULOSE CONTAINING ISOBUTYRYL GROUPS WHICH COMPRISES INITIALLY REACTING UPON CELLULOSE HAVING AN ACTIVATION VALUE OF AT LEAST 0.2 WITH AN ESTERIFICATION BATH ESSENTIALLY CONSISTING OF ISOBUTYRIC ANHYDRIDE AND ZINC CHLORIDE CATALYST WHICH BATH IS SUBSTANTIALLY FREE OF ACYLS OTHER THAN ISOBUTYRYL AT A TEMPERATURE WITHIN THE RANGE OF 100-150*F.; AND AFTER A SUBSTANTIAL ISOBUTYRYL CONTENT HAS BEEN IMPARTED TO THE CELLULOSE ADDING ADDITIONALLY TO THE ESTERIFICATION BATH A LOWER FATTY ACID COMPOUND SELECTED FROM THE ANHYDRIDES AND ACIDS OF THE FATTY ACIDS OF 2-4 CARBON ATOMS IN AN AMOUNT 5-20% OF THE BATH AND CONTINUING THE ESTERFICATION UNTIL THE CELLULOSE HAS BEEN SUBSTANTIALLY, COMPLETELY ESTERIFIED AND IS IN SOLUTION IN THE BATH.
References Cited (Backward Citations)
US2024651A
Cited
US2353423A
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US2376422A
Cited
US2362576A
Cited
US2373630A
Cited
US2622080A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-03-24 | 1961-09-23 | 1962-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-03-24 | 1965-09-23 | 1966-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-03-24 | 1969-09-23 | 1970-03-25 | $7700.00 | Window Closed / Lapsed |