US2560156A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of separating carboxylic acids resulting from the liquid phase oxidation of oleic acid
Assignee: EIDP Inc
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Filing: 1947-12-18
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Granted: 1951-07-10
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Expires: 1967-12-18
Abstract
No abstract record available.
Inventors
- 👤 Cavanaugh Robert Morris
- 👤 Weir Robert Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:37
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/487; C07C51/493
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
100 words
IN THE SEPARATION OF THE CARBOXYLIC ACIDS RESULTING FROM THE OXIDATION OF OLEIC ACID BY MEANS OF NITRIC ACID, THE METHOD OF OBTAINING ESTERS OF SUBERIC AND AZELIC ACIDS WHICH COMPRISES REMOVING COMPLETELTY THE WATER AND NITRIC ACID FROM THE REACTION MIXTURE BY DISTILLATION UNDER REDUCED PRESSURE, SUBSEQUENTLY DISTILLING OFF THE MONOCARBOXYLIC ACIDS AND THE LOWER DICARBOXYLIC ACIDS UNDER REDUCED PRESSURE, ESTERIFYING THE RESIDUAL HIGHER BOILING DICARBOXYLIC ACIDS BY MEANS OF A NORMALLY LIQUID ALIPHATIC ALCOHOL, FRACTIONALLY SEPARATING BY DISTILLATION IN THE RESULTING MIXTURE OF ESTERS, AND OBTAINING IN SUBSTANTIALLY SEPARATED FORM THE ESTERS OF SUBERIC AND AZELAIC ACIDS RESPECTIVELY.
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) | 1954-07-09 | 1955-01-08 | 1955-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-09 | 1959-01-08 | 1959-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-09 | 1963-01-08 | 1963-07-10 | $7700.00 | Window Closed / Lapsed |