US3171828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing polymeric polymethylene terephthalates
Assignee: Imperial Chemical Industries Ltd
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Filing: 1960-01-20
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Granted: 1965-03-02
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Expires: 1980-01-20
Abstract
No abstract record available.
Inventors
- 👤 Isaacs Elias
- 👤 Munro Neil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:39
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/83; C08G63/87; F; F16; F16C; F16C3/00; F16C3/04; F16C3/22; F16C3/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
162 words
IN A PROCESS FOR THE MANUFACTURE OF FILAMENT AND FILM-FORMING HIGHLY POLYMERIC POLYMETHYLENE TEREPHTHALATES BY REACTING A DIALKYL ESTER OF TEREPHTHALIC ACID WITH A GLYCOL OF THE SERIES HO(CH2)NOH WHEREIN N IS GREATER THAN 1 BUT NOT EXCEEDING 10 IN THE PRESENCE OF A CATALYST CONSISTING ESSENTIALLY OF A CATALYTIC ALKALINE EARTH METAL COMPOUND PRESENT IN AMOUNTS RANGING FROM ABOUT 0.01 TO ABOUT 0.20 PERCENT BASED ON THE WEIGHT OF DIALKYL TEREPHTHALATE TO PRODUCE AN ESTER INTERCHANGE PRODUCT AND SUBSEQUENTLY POLYCONDENSING SAID ESTER INTERCHANGE PRODUCT, THE IMPROVEMENT OF CONVERTING, PRIOR TO SAID POLYCONDENSING STEP, AT LEAST A PORTION OF SAID ALKALINE EARTH METAL COMPOUND PRESENT IN SAID ESTER INTERCHANGE PRODUCT INTO A CATALYTICALLY INERT SALT OF SAID ALKALINE EARTH METAL AND A PHOSPHORUS ACID WHICH SALT IS SOLUBLE IN BOTH THE POLYCONDENSATION REACTION MIXTURE AND THE RESULTANT POLYESTER PRODUCT AND POLYCONDENSING SAID ESTER INTERCHANGE PRODUCT IN THE PRESENCE OF SAID CATALYTICALLY INERT SALT OF SAID ALKALINE EARTH METAL AND A POLYCONDENSATION CATALYST.
Claim 2
Dependent Claim
162 words
IN A PROCESS FOR THE MANUFACTURE OF FILAMENT AND FILM-FORMING HIGHLY POLYMERIC POLYMETHYLENE TEREPHTHALATES BY REACTING A DIALKYL ESTER OF TEREPHTHALIC ACID WITH A GLYCOL OF THE SERIES HO(CH2)NOH WHEREIN N IS GREATER THAN 1 BUT NOT EXCEEDING 10 IN THE PRESENCE OF A CATALYST CONSISTING ESSENTIALLY OF A CATALYTIC ALKALINE EARTH METAL COMPOUND PRESENT IN AMOUNTS RANGING FROM ABOUT 0.01 TO ABOUT 0.20 PERCENT BASED ON THE WEIGHT OF DIALKYL TEREPHTHALATE TO PRODUCE AN ESTER INTERCHANGE PRODUCT AND SUBSEQUENTLY POLYCONDENSING SAID ESTER INTERCHANGE PRODUCT, THE IMPROVEMENT OF CONVERTING, PRIOR TO SAID POLYCONDENSING STEP, AT LEAST A PORTION OF SAID ALKALINE EARTH METAL COMPOUND PRESENT IN SAID ESTER INTERCHANGE PRODUCT INTO A CATALYTICALLY INERT SALT OF SAID ALKALINE EARTH METAL AND A PHOSPHORUS ACID WHICH SALT IS SOLUBLE IN BOTH THE POLYCONDENSATION REACTION MIXTURE AND THE RESULTANT POLYESTER PRODUCT AND POLYCONDENSING SAID ESTER INTERCHANGE PRODUCT IN THE PRESENCE OF SAID CATALYTICALLY INERT SALT OF SAID ALKALINE EARTH METAL AND A POLYCONDENSATION CATALYST.
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) | 1968-03-01 | 1968-08-31 | 1969-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-01 | 1972-08-31 | 1973-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-01 | 1976-08-31 | 1977-03-02 | $7700.00 | Window Closed / Lapsed |