US3641112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of bis-(beta-hydroxyalkyl) esters of aromatic dicarboxylic acids
Assignee: Teijin Ltd
•
Filing: 1969-05-26
•
Granted: 1972-02-08
•
Expires: 1989-05-26
Abstract
Abstract IT HAS ALREADY BEEN KNOWN TO PREPARE BIS-(B-HYDROXYETHYL) TEREPHTHALATE BY THE REACTION OF TEREPHTHALIC ACID WITH ETHYLENE OXIDE IN THE PRESENCE OF A CATALYST COMPRISING AN ORGANIC AMINE OR ITS SALT. IN THIS INVENTION, THE PROCESS IS CARRIED OUT IN THE CO-PRESENCE OF AT LEAST ONE IRON COMPOUND AS A PROMOTOR. THUS, A CATALYST SYSTEM OF VERY HIGH ACTIVITY IS PROVIDED, AND THE REACTION CAN BE PERFORMED AT A RELATIVELY LOW TEMPERATURE WITH HIGH CONVERSION OF TEREPHTHALIC ACID.
Inventors
- 👤 Yataro Ichikawa
- 👤 Yoshiyuki Yamanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:31
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/24; C07C67/26
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |