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US2647885A
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Production of polyethylene terephthalate using antimony trioxide as polymerization catalyst
Assignee: EIDP Inc
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Filing: 1951-09-28
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Granted: 1953-08-04
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Expires: 1971-09-28
Abstract
No abstract record available.
Inventors
- 👤 Harry R Billica
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:49
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/85; C08G63/86; C08G63/866
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
59 words
IN THE PROCESS FOR PRODUCING FILAMENT- AND FILM-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYLENE GLYCOL IS REACTED UNDER ESTER INTERCHANGE CONDITIONS WITH AN ALKYL ESTER OF TEREPHTHALIC ACID WHEREIN THE ALKYL ESTER OF TEREPHTHALIC CARBON ATOMS, AND THE RESULTING GLYCOL TEREPHTHALATE IS POLYMERIZED, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE POLYMERIZATION REACTION IN THE PRESENCE OF CATALYTIC AMOUNTS OF ANTIMONY TRIOXIDE.
Claim 2
Dependent Claim
59 words
IN THE PROCESS FOR PRODUCING FILAMENT- AND FILM-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYLENE GLYCOL IS REACTED UNDER ESTER INTERCHANGE CONDITIONS WITH AN ALKYL ESTER OF TEREPHTHALIC ACID WHEREIN THE ALKYL ESTER OF TEREPHTHALIC CARBON ATOMS, AND THE RESULTING GLYCOL TEREPHTHALATE IS POLYMERIZED, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE POLYMERIZATION REACTION IN THE PRESENCE OF CATALYTIC AMOUNTS OF ANTIMONY TRIOXIDE.
References Cited (Backward Citations)
US2465319A
Cited
US2534028A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-08-03 | 1957-02-02 | 1957-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-08-03 | 1961-02-02 | 1961-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-08-03 | 1965-02-02 | 1965-08-04 | $7700.00 | Window Closed / Lapsed |