Patent US2641592A successfully refreshed from Google Patents.
US2641592A
Expired / Lapsed
US
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Production of polyethylene terephthalate with cobaltous acetate as catalyst
Assignee: EIDP Inc
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Filing: 1951-07-24
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Granted: 1953-06-09
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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
2026-10-23 11:53
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/826
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
IN THE PROCESS FOR PRODUCING FILAMENT- AND FILM-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYL GLYCOL IS REACTED UNDER ESTER INTERCHANGE CONDITIONS WITH AN ESTER OF TEREPHTHALIC ACID AND A SATURATED ALIPHATIC MONOHYDRIC ALICOHOL 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 CATALYTIC AMOUNTS OF COBALTOUS ACETATE.
Claim 2
Dependent Claim
63 words
IN THE PROCESS FOR PRODUCING FILAMENT- AND FILM-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYL GLYCOL IS REACTED UNDER ESTER INTERCHANGE CONDITIONS WITH AN ESTER OF TEREPHTHALIC ACID AND A SATURATED ALIPHATIC MONOHYDRIC ALICOHOL 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 CATALYTIC AMOUNTS OF COBALTOUS ACETATE.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-08 | 1956-12-08 | 1957-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-08 | 1960-12-08 | 1961-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-08 | 1964-12-08 | 1965-06-09 | $7700.00 | Window Closed / Lapsed |