US3028366A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalytic process for the preparation of substantially colorless polymeric glycol terephthalates
Assignee: EIDP Inc
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Filing: 1956-06-26
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Granted: 1962-04-03
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Expires: 1976-06-26
Abstract
No abstract record available.
Inventors
- 👤 Jr Robert Fry Engle
- 👤 Pohl Herbert Ackland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:28
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/87
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
93 words
IN THE PROCESS OF POLYMERIZING A GLYCOL ESTER OF TEREPHTHALIC ACID IN THE PRESENCE OF A METAL-CONTAINING CATALYST FOR THE POLYMERIZATION THEREOF TO PRODUCE A LINEAR FIBER-FORMING POLYESTER THEREFROM, THE IMPROVEMENT OF PRODUCING A POLYMER SUBSTANTIALLY FREE FROM COLOR WHICH COMPRISES HEATING THE SAID GLYCOL ESTER UNDER REDUCED PRESSURE IN THE PRESENCE OF A PHOSPHORIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF PHOSPHORIC ACID, ALKUL PHOSPHATES, HYDROXYALKYL PHOSPHATES, AND ARYL PHOSPHATES IN AN AMOUNT LESS THAN 0.2 MOL PERCENT, BASED ON THE TEREPHTHALATE CONTENT OF THE POLYMER, UNTIL A FIBERFORMING POLYMER IS PRODUCED.
Claim 2
Dependent Claim
93 words
IN THE PROCESS OF POLYMERIZING A GLYCOL ESTER OF TEREPHTHALIC ACID IN THE PRESENCE OF A METAL-CONTAINING CATALYST FOR THE POLYMERIZATION THEREOF TO PRODUCE A LINEAR FIBER-FORMING POLYESTER THEREFROM, THE IMPROVEMENT OF PRODUCING A POLYMER SUBSTANTIALLY FREE FROM COLOR WHICH COMPRISES HEATING THE SAID GLYCOL ESTER UNDER REDUCED PRESSURE IN THE PRESENCE OF A PHOSPHORIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF PHOSPHORIC ACID, ALKUL PHOSPHATES, HYDROXYALKYL PHOSPHATES, AND ARYL PHOSPHATES IN AN AMOUNT LESS THAN 0.2 MOL PERCENT, BASED ON THE TEREPHTHALATE CONTENT OF THE POLYMER, UNTIL A FIBERFORMING POLYMER IS PRODUCED.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-04-02 | 1965-10-02 | 1966-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-04-02 | 1969-10-02 | 1970-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-04-02 | 1973-10-02 | 1974-04-03 | $7700.00 | Window Closed / Lapsed |