US2518283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of polyethylene terephthalate
Assignee: EIDP Inc
•
Filing: 1948-07-29
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Granted: 1950-08-08
•
Expires: 1968-07-29
Abstract
No abstract record available.
Inventors
- 👤 Casassa Edward Francis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:03
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/84
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
IN THE PROCESS FOR PRODUCING FIBER-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYLENE GLYCOL IS REACTED WITH DIMETHYL TEREPHTHALATE TO FORM BY ESTER INTERCHANGE, BIS-2-HYDROXY-ETHYL TEREPHTHALATE IS THEREAFTER POLYMERIZED TO A FIBERFORMING LINEAR POLYMER BY HEATING THE SAME UNDER SUB-ATMOSPHERIC PRESSURE UNTIL A LINEAR POLYMER OF THE DESIRED INTRINSIC VISCOSITY IS OBTAINED, THE IMPROVEMENT WHICH COMPRISES EFFECTING THE ESTER INTERCHANGE AND POLYMERIZATION IN THE PRESENCE OF ZINC BORATE AS A CATALYST.
Claim 2
Dependent Claim
68 words
IN THE PROCESS FOR PRODUCING FIBER-FORMING POLYETHYLENE TEREPHTHALATE WHEREIN ETHYLENE GLYCOL IS REACTED WITH DIMETHYL TEREPHTHALATE TO FORM BY ESTER INTERCHANGE, BIS-2-HYDROXY-ETHYL TEREPHTHALATE IS THEREAFTER POLYMERIZED TO A FIBERFORMING LINEAR POLYMER BY HEATING THE SAME UNDER SUB-ATMOSPHERIC PRESSURE UNTIL A LINEAR POLYMER OF THE DESIRED INTRINSIC VISCOSITY IS OBTAINED, THE IMPROVEMENT WHICH COMPRISES EFFECTING THE ESTER INTERCHANGE AND POLYMERIZATION IN THE PRESENCE OF ZINC BORATE AS A CATALYST.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-07 | 1954-02-06 | 1954-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-07 | 1958-02-06 | 1958-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-07 | 1962-02-06 | 1962-08-08 | $7700.00 | Window Closed / Lapsed |