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US3047561A Expired / Lapsed US ⏱️ 0.0 years remaining

Preparation of stable cellulose triesters

Assignee: Eastman Kodak Co
•
Filing: 1959-09-02
•
Granted: 1962-07-31
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Expires: 1979-09-02
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Abstract

No abstract record available.

Inventors

  • 👤 Carlton L Crane

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 16:49
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 Cited
US2203700A Cited
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

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