Patent US3047561A successfully refreshed from Google Patents.
US3047561A
Expired / Lapsed
US
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Preparation of stable cellulose triesters
Assignee: Eastman Kodak Co
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Filing: 1959-09-02
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Granted: 1962-07-31
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Expires: 1979-09-02
Abstract
No abstract record available.
Inventors
- 👤 Carlton L Crane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:40
CPC Classifications
C; C08; C08B; C08B3/00; C08B3/08; C08B3/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
A METHOD OF PREPARING CELLULOSE TRIESTERS OF EXCELLENT STABILITY WHICH COMPRISES SUBSTANTIALLY COMPLETELY ESTERIFYING CELLULOSE WITH AN ESTERIFICATION BATH OF FATTY ACID ANHYDRIDE DILUENT AND SULFURIC ACID CATALYST AND SUBJECTING THE THUS FORMED CELLULAR ESTER IN SOLUTION IN THE COMPLETED ESTERIFICATION BATH TO A TEMPERATURE OF 200350*F. UNDER ANHYDROUS CONDITIONS AFTER THE SULFURIC ACID CATALYST USED HAS BEEN COMPLETELY NEUTRALIZED WITH A CHEMICALLY EQUIVALENT AMOUNT OF BASE MATERIAL SELECTED FROM THE GROUP CONSISTING OF THE CARBONATES, HYDROXIDES, OXIDE AND ACETATES OF CALCIUM, MAGNESIUM, BARIUM, IRON, AND ALUMINUM PLUS FURTHER ADDITION OF BASE MATERIAL SO THAT THE TOTAL BASE MATERIAL ADDED TO THE BATH IS CHEMICALLY EQUIVALENT TO 1 1/2 TO 5 TIMES THE AMOUNT OF SULFURIC ACID CATALYST USED.
Claim 2
Independent Claim
119 words
A METHOD OF PREPARING CELLULOSE TRIESTERS OF EXCELLENT STABILITY WHICH COMPRISES SUBSTANTIALLY COMPLETELY ESTERIFYING CELLULOSE WITH AN ESTERIFICATION BATH OF FATTY ACID ANHYDRIDE DILUENT AND SULFURIC ACID CATALYST AND SUBJECTING THE THUS FORMED CELLULAR ESTER IN SOLUTION IN THE COMPLETED ESTERIFICATION BATH TO A TEMPERATURE OF 200350*F. UNDER ANHYDROUS CONDITIONS AFTER THE SULFURIC ACID CATALYST USED HAS BEEN COMPLETELY NEUTRALIZED WITH A CHEMICALLY EQUIVALENT AMOUNT OF BASE MATERIAL SELECTED FROM THE GROUP CONSISTING OF THE CARBONATES, HYDROXIDES, OXIDE AND ACETATES OF CALCIUM, MAGNESIUM, BARIUM, IRON, AND ALUMINUM PLUS FURTHER ADDITION OF BASE MATERIAL SO THAT THE TOTAL BASE MATERIAL ADDED TO THE BATH IS CHEMICALLY EQUIVALENT TO 1 1/2 TO 5 TIMES THE AMOUNT OF SULFURIC ACID CATALYST USED.
References Cited (Backward Citations)
US2072260A
Cited
US2126190A
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US2203700A
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US2456688A
Cited
US2582049A
Cited
US2673202A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-07-30 | 1966-01-29 | 1966-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-07-30 | 1970-01-29 | 1970-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-07-30 | 1974-01-29 | 1974-07-31 | $7700.00 | Window Closed / Lapsed |