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US3376265A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing polyesters

Assignee: Toray Industries Inc
•
Filing: 1963-10-15
•
Granted: 1968-04-02
•
Expires: 1983-10-15
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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 04:10
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-

References Cited (Backward Citations)

US2249950A Cited
US2921051A Cited
US3050533A Cited
US3070575A Cited
US3055868A Cited
US3055869A Cited

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

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