US2916474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of preparing polymeric terephthalic esters by interchange between a glycol and a dialkyl ester of terephthalic acid
Assignee: EIDP Inc
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Filing: 1955-12-16
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Granted: 1959-12-08
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Expires: 1975-12-16
Abstract
No abstract record available.
Inventors
- 👤 Jr Robert F Engle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:11
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/20; C08G63/78; C08G63/82; C08G63/84; C08G63/85
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
73 words
IN THE PROCESS OF PREPARING FIBER-FORMING LINEAR CONDENSATION POLYESTERS FROM GLYCOL ESTERS OF DICARBOXYLIC ACIDS IN WHICH A LOWER ALKYL ESTER OF ADICARBOXYLIC ACID IS SUBJECTED TO ESTER INTERCHANGE WITH A GLYCOL FOLLOWED BY THE POLYCONDENSATION OF THE GLYCOL ESTER AT A CONDENSATION TEMPERATURE, THE IMPROVEMENT WHICH COMPRISES EFFECTING THE ESTER INTERCHANGE AND POLYCONDENSATION WITH HEATING IN THE PRESENCE OF CATALYTIC AMOUNTS OF A LANTHANUM TITANATE WITH THE ELIMINATION OF LOWER MONOHYDRIC ALCOHOL.
Claim 2
Dependent Claim
73 words
IN THE PROCESS OF PREPARING FIBER-FORMING LINEAR CONDENSATION POLYESTERS FROM GLYCOL ESTERS OF DICARBOXYLIC ACIDS IN WHICH A LOWER ALKYL ESTER OF ADICARBOXYLIC ACID IS SUBJECTED TO ESTER INTERCHANGE WITH A GLYCOL FOLLOWED BY THE POLYCONDENSATION OF THE GLYCOL ESTER AT A CONDENSATION TEMPERATURE, THE IMPROVEMENT WHICH COMPRISES EFFECTING THE ESTER INTERCHANGE AND POLYCONDENSATION WITH HEATING IN THE PRESENCE OF CATALYTIC AMOUNTS OF A LANTHANUM TITANATE WITH THE ELIMINATION OF LOWER MONOHYDRIC ALCOHOL.
References Cited (Backward Citations)
US2720502A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-12-07 | 1963-06-08 | 1963-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-12-07 | 1967-06-08 | 1967-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-12-07 | 1971-06-08 | 1971-12-08 | $7700.00 | Window Closed / Lapsed |