Patent US3376265A successfully refreshed from Google Patents.
US3376265A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing polyesters
Assignee: Toray Industries Inc
•
Filing: 1963-10-15
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Granted: 1968-04-02
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Expires: 1983-10-15
Abstract
No abstract record available.
Inventors
- 👤 Yokouchi Rei
- 👤 Ichikawa Yoshimitsu
- 👤 Hosoi Etsuro
- 👤 Aoki Toshikazu
- 👤 Takagishi Kenji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:02
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/83
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
IN A PROCESS FOR PRODUCING POLYESTERS HAVING A SOFTENING POINT BETWEEN 209*C. AND 230*C. FROM THE MONO- AND DI-ESTERS OF TEREPHTHALIC ACID OF ALKANOLS HAVING 1-4 CARBON ATOMS AND ETHYLENE GLYCOL BY MEANS OF AN ESTER INTERCHANGE AND POLYMERIZATION REACTION, THE IMPROVEMENT WHICH COMPRISES (1) EMPLOYING AN ESTER INTERCHANGE CATALYST CONSISTING OF ANTIMONY OXIDE AND (2) CAR-
Claim 2
Dependent Claim
57 words
IN A PROCESS FOR PRODUCING POLYESTERS HAVING A SOFTENING POINT BETWEEN 209*C. AND 230*C. FROM THE MONO- AND DI-ESTERS OF TEREPHTHALIC ACID OF ALKANOLS HAVING 1-4 CARBON ATOMS AND ETHYLENE GLYCOL BY MEANS OF AN ESTER INTERCHANGE AND POLYMERIZATION REACTION, THE IMPROVEMENT WHICH COMPRISES (1) EMPLOYING AN ESTER INTERCHANGE CATALYST CONSISTING OF ANTIMONY OXIDE AND (2) CAR-
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-04-02 | 1971-10-02 | 1972-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-04-02 | 1975-10-02 | 1976-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-04-02 | 1979-10-02 | 1980-04-02 | $7700.00 | Window Closed / Lapsed |