Patent US2650213A successfully refreshed from Google Patents.
US2650213A
Expired / Lapsed
US
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Production of polyethylene terephthalate
Assignee: EIDP Inc
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Filing: 1951-07-24
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Granted: 1953-08-25
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Expires: 1971-07-24
Abstract
No abstract record available.
Inventors
- 👤 Jr Charles H Hofrichter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:43
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/87; C08G63/85; Y; Y10; Y10S; Y10S138/00; Y10S138/07
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
IN THE PROCESS FOR PRODUCING FILAMENT- AND FILM-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYLENE GLYCOL IS REACTED UNDER ESTER INTERCHANGE CONDITIONS WITH AN ESTER OF TEREPHTHALIC ACID AND A SATURATED ALIPHATIC MONOHYDRIC ALCOHOL CONTAINING FROM 1 TO 4 CARBON ATOMS, AND THE RESULTING GLYCOL TEREPHTHALATE IS POLYMERIZED, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE POLYMERIZATION REACTION IN THE PRESENCE OF A CATALYST SYSTEM CONSISTING OF FROM 0.005 TO 0.1% BY WEIGHT OF LITHARGE, FROM 0.01 TO 0.15% BY WEIGHT OF ANTIMONY TRIOXIDE, AND FROM 0.01 TO 0.5% BY WEIGHT OF TRIPHENYL PHOSPHATE, BASED ON THE WEIGHT OF SAID ESTER TEREPHTHALIC ACID.
Claim 2
Dependent Claim
99 words
IN THE PROCESS FOR PRODUCING FILAMENT- AND FILM-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYLENE GLYCOL IS REACTED UNDER ESTER INTERCHANGE CONDITIONS WITH AN ESTER OF TEREPHTHALIC ACID AND A SATURATED ALIPHATIC MONOHYDRIC ALCOHOL CONTAINING FROM 1 TO 4 CARBON ATOMS, AND THE RESULTING GLYCOL TEREPHTHALATE IS POLYMERIZED, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE POLYMERIZATION REACTION IN THE PRESENCE OF A CATALYST SYSTEM CONSISTING OF FROM 0.005 TO 0.1% BY WEIGHT OF LITHARGE, FROM 0.01 TO 0.15% BY WEIGHT OF ANTIMONY TRIOXIDE, AND FROM 0.01 TO 0.5% BY WEIGHT OF TRIPHENYL PHOSPHATE, BASED ON THE WEIGHT OF SAID ESTER TEREPHTHALIC ACID.
References Cited (Backward Citations)
US2437046A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-08-24 | 1957-02-23 | 1957-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-08-24 | 1961-02-23 | 1961-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-08-24 | 1965-02-23 | 1965-08-25 | $7700.00 | Window Closed / Lapsed |