US2823230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing terephthalic acid
Assignee: Henkel AG and Co KGaA
•
Filing: 1956-08-23
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Granted: 1958-02-11
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Expires: 1976-08-23
Abstract
No abstract record available.
Inventors
- 👤 Raecke Bernhard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:05
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/41; C07C51/416
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
80 words
IN A PROCESS OF PRODUCING AROMATIC MONOCYCLIC DICARBOXYLIC ACIDS FROM AROMATIC MONOCYCLIC MONOCARBOXYLIC ACIDS, THE STEPS COMPRISING CONVERTING SAID MONOCYCLIC MONOCARBOXYLIC ACIDS INTO SALTS OF THE GROUP CONSISTING OF THE ALKALI METAL SALTS THEREOF, AND HEATING SAID SALTS IN A SUBSTANTIALLY OXYGEN-FREE INERT ATMOSPHERE TO A TEMPERATURE ABOVE ABOUT 340*C. AND BELOW THE TEMPERATURE AT WHICH SUBSTANTIAL DECOMPOSITION OF THE STARTING MATERIALS AND REACTION PRODUCTS TAKES PLACE TO INTRODUCE A SECOND CARBOXYL SALT GROUP INTO SAID MONOCYCLIC MONOCARBOXYLIC ACID SALTS.
Claim 2
Dependent Claim
80 words
IN A PROCESS OF PRODUCING AROMATIC MONOCYCLIC DICARBOXYLIC ACIDS FROM AROMATIC MONOCYCLIC MONOCARBOXYLIC ACIDS, THE STEPS COMPRISING CONVERTING SAID MONOCYCLIC MONOCARBOXYLIC ACIDS INTO SALTS OF THE GROUP CONSISTING OF THE ALKALI METAL SALTS THEREOF, AND HEATING SAID SALTS IN A SUBSTANTIALLY OXYGEN-FREE INERT ATMOSPHERE TO A TEMPERATURE ABOVE ABOUT 340*C. AND BELOW THE TEMPERATURE AT WHICH SUBSTANTIAL DECOMPOSITION OF THE STARTING MATERIALS AND REACTION PRODUCTS TAKES PLACE TO INTRODUCE A SECOND CARBOXYL SALT GROUP INTO SAID MONOCYCLIC MONOCARBOXYLIC ACID SALTS.
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) | 1961-02-10 | 1961-08-12 | 1962-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-10 | 1965-08-12 | 1966-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-10 | 1969-08-12 | 1970-02-11 | $7700.00 | Window Closed / Lapsed |