Patent US2951827A successfully refreshed from Google Patents.
US2951827A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of production of high-molecular linear polyesters from aromatic dicarboxylicacid diolesters
Assignee: Glanzstoff AG
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Filing: 1955-02-17
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Granted: 1960-09-06
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Expires: 1975-02-17
Abstract
No abstract record available.
Inventors
- 👤 Siggel Erhard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:53
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/83
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
THE METHOD OF PREPARING A HIGH MOLECULAR LINEAR POLYESTER OF ETHYLENEGLYCOL AND TEREPHTHALIC ACID WHICH COMPRISES ADMIXING WITH THE ETHYLENEGLYCOL DIESTER OF TEREPHTHALIC ACID PRIOR TO CONDENSATION A CATALYTIC AMOUNT, LESS THAN ABOUT 0.5 MOL PERCENT PER 1 MOLE OF SAID DIESTER, OF A CONDENSATION CATALYST CONSISTING ESSENTIALLY OF ZINC ACETATE, THE AMOUNT OF SAID CATALYST BEING CALCULATED FOR THE ZINC CONTENT, AND THEN POLYCONDENSING SAID DIESTER IN VACUO AT ABOUT 10 MM. MERCURY PRESSURE AND AT A TEMPERATURE FROM ABOUT 10* TO ABOUT 50*C. ABOVE THE MELTING POINT OF THE POLYESTER TO BE OBTAINED, FOR A PERIOD OF ABOUT 1 TO 2 HOURS.
Claim 2
Independent Claim
104 words
THE METHOD OF PREPARING A HIGH MOLECULAR LINEAR POLYESTER OF ETHYLENEGLYCOL AND TEREPHTHALIC ACID WHICH COMPRISES ADMIXING WITH THE ETHYLENEGLYCOL DIESTER OF TEREPHTHALIC ACID PRIOR TO CONDENSATION A CATALYTIC AMOUNT, LESS THAN ABOUT 0.5 MOL PERCENT PER 1 MOLE OF SAID DIESTER, OF A CONDENSATION CATALYST CONSISTING ESSENTIALLY OF ZINC ACETATE, THE AMOUNT OF SAID CATALYST BEING CALCULATED FOR THE ZINC CONTENT, AND THEN POLYCONDENSING SAID DIESTER IN VACUO AT ABOUT 10 MM. MERCURY PRESSURE AND AT A TEMPERATURE FROM ABOUT 10* TO ABOUT 50*C. ABOVE THE MELTING POINT OF THE POLYESTER TO BE OBTAINED, FOR A PERIOD OF ABOUT 1 TO 2 HOURS.
References Cited (Backward Citations)
US2681360A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-09-06 | 1964-03-07 | 1964-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-09-06 | 1968-03-07 | 1968-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-09-06 | 1972-03-07 | 1972-09-06 | $7700.00 | Window Closed / Lapsed |