US2563820A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of aryl dicarboxylic acids
Assignee: California Research LLC
•
Filing: 1947-10-04
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Granted: 1951-08-14
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Expires: 1967-10-04
Abstract
No abstract record available.
Inventors
- 👤 John L Darragh
- 👤 Robert J Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:41
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/295
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
A PROCESS FOR PRODUCING BENZENE CARBOXYLIC ACIDS WHICH COMPRISES OXIDIZING A XYLENE HAVING AT LEAST 1 AND NOT MORE THAN 2 CHLORINE ATOMS SUBSTITUTED IN EACH METHYL GROUP BY CONTACT WITH AQUEOUS CAUSTIC ALKALI IN AN OXIDATION ZONE AT A TEMPERATURE IN THE RANGE ABOUT 300 TO 400* C. UNDER A PRESSURE SUFFICIENT TO MAINTAIN THE AQUEOUS CAUSTIC ALKALI IN LIQUID PHASE TO FORM A REACTION PRODUCT COMPRISING BENZENE CARBOXYLIC ACID SALTS AND HYDROGEN.
Claim 2
Dependent Claim
74 words
A PROCESS FOR PRODUCING BENZENE CARBOXYLIC ACIDS WHICH COMPRISES OXIDIZING A XYLENE HAVING AT LEAST 1 AND NOT MORE THAN 2 CHLORINE ATOMS SUBSTITUTED IN EACH METHYL GROUP BY CONTACT WITH AQUEOUS CAUSTIC ALKALI IN AN OXIDATION ZONE AT A TEMPERATURE IN THE RANGE ABOUT 300 TO 400* C. UNDER A PRESSURE SUFFICIENT TO MAINTAIN THE AQUEOUS CAUSTIC ALKALI IN LIQUID PHASE TO FORM A REACTION PRODUCT COMPRISING BENZENE CARBOXYLIC ACID SALTS AND HYDROGEN.
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) | 1954-08-13 | 1955-02-12 | 1955-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-08-13 | 1959-02-12 | 1959-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-08-13 | 1963-02-12 | 1963-08-14 | $7700.00 | Window Closed / Lapsed |