US2753369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of dimethyl terephthalate
Assignee: EIDP Inc
•
Filing: 1953-07-09
•
Granted: 1956-07-03
•
Expires: 1973-07-09
Abstract
No abstract record available.
Inventors
- 👤 Robert H Sullivan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:43
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/48; C07C67/60
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
36 words
A PROCESS FOR REMOVING COLOR-FORMING AND LIGHTABSORBIN IMPURITIES FROM DIMETHYL TEREPHTHALATE COMPRISING DISSOLVING THE DIMETHYL TEREPHTHALATE IN CHLOROFORM AND BRINGING THE SOLUTION IN INTIMATE CONTACT WITH AN 0.5 TO 5% AQUEOUS SOLUTION OF ALKALI METAL HYDROXIDE.
Claim 2
Dependent Claim
36 words
A PROCESS FOR REMOVING COLOR-FORMING AND LIGHTABSORBIN IMPURITIES FROM DIMETHYL TEREPHTHALATE COMPRISING DISSOLVING THE DIMETHYL TEREPHTHALATE IN CHLOROFORM AND BRINGING THE SOLUTION IN INTIMATE CONTACT WITH AN 0.5 TO 5% AQUEOUS SOLUTION OF ALKALI METAL HYDROXIDE.
References Cited (Backward Citations)
US1899919A
Cited
US2131925A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-07-03 | 1960-01-02 | 1960-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-07-03 | 1964-01-02 | 1964-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-07-03 | 1968-01-02 | 1968-07-03 | $7700.00 | Window Closed / Lapsed |