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US2595343A
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Production of polyesters by reacting a dicarboxylic acid with a diphenol
Assignee: Celanese Corp
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Filing: 1948-08-06
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Granted: 1952-05-06
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Expires: 1968-08-06
Abstract
No abstract record available.
Inventors
- 👤 Drewitt James Gordon Napier
- 👤 Lincoln James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:20
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/19; C08G63/191
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
PROCESS FOR THE PRODUCTION OF POLYESTERS, WHICH CONSISTS IN HEATING A FREE DICARBOXYLIC ACID WHOSE TWO CARBOXYLIC ACID GROUPS ARE ITS SOLE REACTIVE GROUPS WITH A SUBSTANTIALLY EQUIMOLECULAR PROPORTION OF A REACTANT MEDIUM SELECTED FROM THE GROUP CONSISTING OF A FREE DIPHENOL, WHOSE TWO PHENOLIC GROUPS ARE ITS SOLE REACTIVE GROUPS, TOGETHER WITH ACETIC ANHYDRIDE AND THE CORRESPONDING DIPHENOL DIACETATE.
Claim 2
Dependent Claim
60 words
PROCESS FOR THE PRODUCTION OF POLYESTERS, WHICH CONSISTS IN HEATING A FREE DICARBOXYLIC ACID WHOSE TWO CARBOXYLIC ACID GROUPS ARE ITS SOLE REACTIVE GROUPS WITH A SUBSTANTIALLY EQUIMOLECULAR PROPORTION OF A REACTANT MEDIUM SELECTED FROM THE GROUP CONSISTING OF A FREE DIPHENOL, WHOSE TWO PHENOLIC GROUPS ARE ITS SOLE REACTIVE GROUPS, TOGETHER WITH ACETIC ANHYDRIDE AND THE CORRESPONDING DIPHENOL DIACETATE.
References Cited (Backward Citations)
US2331169A
Cited
US2496933A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-05-06 | 1955-11-05 | 1956-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-05-06 | 1959-11-05 | 1960-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-05-06 | 1963-11-05 | 1964-05-06 | $7700.00 | Window Closed / Lapsed |