Patent US2496933A successfully refreshed from Google Patents.
US2496933A
Expired / Lapsed
US
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Linear polyesters of hydroquinone, saturated glycols and dicarboxylic acids and their preparation
Assignee: Eastman Kodak Co
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Filing: 1946-05-25
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Granted: 1950-02-07
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Expires: 1966-05-25
Abstract
No abstract record available.
Inventors
- 👤 John R Caldwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:54
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/19; C08G63/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
115 words
A METHOD OF PREPARING A LINEAR POLYESTER WHICH COMPRISES HEATING A MIXTURE OF 0.8-0.4 MOLOF HYDROQUINONE, 0.2-0.6 MOL. OF A SATURATED ALIPHATIC GLYCOL CONTAINING ONLY C, H AND O AND HAVING GLYCOL HYDROZYL GROUPS AS THE ONLY REACTIVE GROUPS THEREIN, A DICARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF SUCCINIC, GLUTARIC, ADIPIC, PIMELIC, SUBERIC, AZELAIC, SEBACIC AND DIMERIZED OLEIC ACID AND ACETIC ANHYDRIDE, THE DICARBOXYLIC ACID BEING IN AN AMOUNT SUFFICIENT TO ESTERIFY THE HYDROQUINONE AND THE GLYCOL AND THE ACETIC ANHYDRIDE BEING IN AN AMOUNT GREATER THAN THAT OF THE DICARBOXYLIC ACID, UNTIL ACETIC ACID BEINGS TO DISTIL FROM THE MASS AND CONTINUING THE HEATING UNTIL 70-80% OF THE THEORETICAL ACETIC ACID DISTILS THEREFROM.
Claim 2
Independent Claim
115 words
A METHOD OF PREPARING A LINEAR POLYESTER WHICH COMPRISES HEATING A MIXTURE OF 0.8-0.4 MOLOF HYDROQUINONE, 0.2-0.6 MOL. OF A SATURATED ALIPHATIC GLYCOL CONTAINING ONLY C, H AND O AND HAVING GLYCOL HYDROZYL GROUPS AS THE ONLY REACTIVE GROUPS THEREIN, A DICARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF SUCCINIC, GLUTARIC, ADIPIC, PIMELIC, SUBERIC, AZELAIC, SEBACIC AND DIMERIZED OLEIC ACID AND ACETIC ANHYDRIDE, THE DICARBOXYLIC ACID BEING IN AN AMOUNT SUFFICIENT TO ESTERIFY THE HYDROQUINONE AND THE GLYCOL AND THE ACETIC ANHYDRIDE BEING IN AN AMOUNT GREATER THAN THAT OF THE DICARBOXYLIC ACID, UNTIL ACETIC ACID BEINGS TO DISTIL FROM THE MASS AND CONTINUING THE HEATING UNTIL 70-80% OF THE THEORETICAL ACETIC ACID DISTILS THEREFROM.
References Cited (Backward Citations)
US2028908A
Cited
US2035578A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-02-06 | 1953-08-08 | 1954-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-06 | 1957-08-08 | 1958-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-06 | 1961-08-08 | 1962-02-07 | $7700.00 | Window Closed / Lapsed |