Patent US3039998A successfully refreshed from Google Patents.
US3039998A
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Preparation of polyesters using an onium compound as a catalyst
Assignee: Onderzoekings Instituut Research
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Filing: 1956-12-20
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Granted: 1962-06-19
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Expires: 1976-12-20
Abstract
No abstract record available.
Inventors
- 👤 Jan A K Boerma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:10
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/87
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
IN A PROCESS FOR THE PRODUCTION OF A FILAMENT FORMING POLYETHYLENE TEREPHTHALATE HAVING A MELTING POINT OF ABOUT 260*C., A VISCOSITY IN A 1% SOLUTION IN METACRESOL AT 30*C. OF AT LEAST 0.39, AND WHEREIN BIS-HYDROXY-ETHYLTEREPHTHALATE IS POLYMERIZED IN THE PRESENCE OF A CATALYST, THE IMPROVEMENT WHICH COMPRISES POLYCONDENSING THE SAID BIS-HYDROXY-ETHYL-TEREPHTHALATE INT HE ABSENCE OF A METAL CONTAINING CATALYST AND USING AS A CATALYST AN ORGANIC METAL-FREE QUATERNARY AMMONIUM COMPOUND, WHEREIN THE POLYETHYLENE TEREPHTHALATE PRODUCED HAS IMPROVED RESISTANCE TO HEAT DEGRADATION AND IMPROVED CLARITY.
Claim 2
Dependent Claim
85 words
IN A PROCESS FOR THE PRODUCTION OF A FILAMENT FORMING POLYETHYLENE TEREPHTHALATE HAVING A MELTING POINT OF ABOUT 260*C., A VISCOSITY IN A 1% SOLUTION IN METACRESOL AT 30*C. OF AT LEAST 0.39, AND WHEREIN BIS-HYDROXY-ETHYLTEREPHTHALATE IS POLYMERIZED IN THE PRESENCE OF A CATALYST, THE IMPROVEMENT WHICH COMPRISES POLYCONDENSING THE SAID BIS-HYDROXY-ETHYL-TEREPHTHALATE INT HE ABSENCE OF A METAL CONTAINING CATALYST AND USING AS A CATALYST AN ORGANIC METAL-FREE QUATERNARY AMMONIUM COMPOUND, WHEREIN THE POLYETHYLENE TEREPHTHALATE PRODUCED HAS IMPROVED RESISTANCE TO HEAT DEGRADATION AND IMPROVED CLARITY.
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) | 1965-06-18 | 1965-12-18 | 1966-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-06-18 | 1969-12-18 | 1970-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-06-18 | 1973-12-18 | 1974-06-19 | $7700.00 | Window Closed / Lapsed |