US2905708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of purified dimethyl terephthalate
Assignee: Standard Oil Co
•
Filing: 1957-12-02
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Granted: 1959-09-22
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Expires: 1977-12-02
Abstract
No abstract record available.
Inventors
- 👤 Kenneth C Peterson
- 👤 James T Corcoran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:46
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/48; C07C67/00; C07C67/08; C08; C08G; C08G77/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
IN A PROCESS FOR THE PREPARATION OF DIMETHYL TEREPHTHALATE HAVING AN ACID NUMBER LESS THAN ABOUT 0.1 BY THE ESTERIFICATION OF TEREPHTHALIC ACID WITH METHANOL, THE IMPROVEMENT WHICH COMPRISES THE STEPS, PRIOR TO ESTERIFICATION, OF EXTRACTING NON-ESTERIFIABLE ACIDIC CONSTITUENTS FROM A TEREPHTHALIC ACID CONTAINING SAID CONSTITUENTS AND LESS THAN 4% OF OTHER AROMATIC ACIDS WITH WATER AT A TEMPERATURE OF BETWEEN 250 AND 500*F.
Claim 2
Dependent Claim
64 words
IN A PROCESS FOR THE PREPARATION OF DIMETHYL TEREPHTHALATE HAVING AN ACID NUMBER LESS THAN ABOUT 0.1 BY THE ESTERIFICATION OF TEREPHTHALIC ACID WITH METHANOL, THE IMPROVEMENT WHICH COMPRISES THE STEPS, PRIOR TO ESTERIFICATION, OF EXTRACTING NON-ESTERIFIABLE ACIDIC CONSTITUENTS FROM A TEREPHTHALIC ACID CONTAINING SAID CONSTITUENTS AND LESS THAN 4% OF OTHER AROMATIC ACIDS WITH WATER AT A TEMPERATURE OF BETWEEN 250 AND 500*F.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-09-21 | 1963-03-23 | 1963-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-09-21 | 1967-03-23 | 1967-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-09-21 | 1971-03-23 | 1971-09-22 | $7700.00 | Window Closed / Lapsed |