Patent US2818429A successfully refreshed from Google Patents.
US2818429A
Expired / Lapsed
US
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Naphthenohydroxamic acid manufacturing process
Assignee: Standard Oil Co
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Filing: 1956-07-20
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Granted: 1957-12-31
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Expires: 1976-07-20
Abstract
No abstract record available.
Inventors
- 👤 Beretvas Helen Sellei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:00
CPC Classifications
C; C07; C07D; C07D417/00; C07D417/02; C07D417/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
136 words
IN THE PROCESS OF MAKING NAPTHENOHYDROXAMIC ACID BY REACTION OF A NAPHTHENIC ACID ESTER WITH A HYDROXYLAMINE HYDROCHLORIDE AND SODIUM HYDROXIDE IN AN ALCOHOLIC SOLUTION FOLLOWED BY ACIDIFICATION WITH SULFURIC ACID AND PRODUCT PURIFICATION, THE IMPROVED METHOD OF OPERATION WHICH COMPRISES ADDING THE ESTER AND THEN THE SODIUM HYDROXIDE TO AN ALCOHOLIC SOLUTION OF HYDROXYLAMINE HYDROCHLORIDE AT TEMPERATURES IN THE RANGE OF ABOUT 70 TO 130*F. WITH RAPID STIRRING, COOLING THE REACTION MIXTURE, AFTER THE ADDITON OF SODIUM HYDROXIDE, TO A TEMPERATURE IN THE RANGE OF 40 TO 70*F. AND HOLDING THE REACTION MIXTURE IN SAID TEMPERATURE RANGE FOR A PERIOD OF ABOUT 1 TO 20 HOURS, AND INTRODUCING INTO SAID TOTAL REACTION MIXTRUE A TOTAL AMOUNT OF WATER WHICH IS NOT SUBSTANTIALLY MORE ON A WEIGHT BASIS THAN THE AMOUNT OF SODIUM HYDROXIDE INTRODUCED THERETO.
Claim 2
Dependent Claim
136 words
IN THE PROCESS OF MAKING NAPTHENOHYDROXAMIC ACID BY REACTION OF A NAPHTHENIC ACID ESTER WITH A HYDROXYLAMINE HYDROCHLORIDE AND SODIUM HYDROXIDE IN AN ALCOHOLIC SOLUTION FOLLOWED BY ACIDIFICATION WITH SULFURIC ACID AND PRODUCT PURIFICATION, THE IMPROVED METHOD OF OPERATION WHICH COMPRISES ADDING THE ESTER AND THEN THE SODIUM HYDROXIDE TO AN ALCOHOLIC SOLUTION OF HYDROXYLAMINE HYDROCHLORIDE AT TEMPERATURES IN THE RANGE OF ABOUT 70 TO 130*F. WITH RAPID STIRRING, COOLING THE REACTION MIXTURE, AFTER THE ADDITON OF SODIUM HYDROXIDE, TO A TEMPERATURE IN THE RANGE OF 40 TO 70*F. AND HOLDING THE REACTION MIXTURE IN SAID TEMPERATURE RANGE FOR A PERIOD OF ABOUT 1 TO 20 HOURS, AND INTRODUCING INTO SAID TOTAL REACTION MIXTRUE A TOTAL AMOUNT OF WATER WHICH IS NOT SUBSTANTIALLY MORE ON A WEIGHT BASIS THAN THE AMOUNT OF SODIUM HYDROXIDE INTRODUCED THERETO.
References Cited (Backward Citations)
US2168305A
Cited
US2397508A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-12-30 | 1961-07-01 | 1961-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-30 | 1965-07-01 | 1965-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-30 | 1969-07-01 | 1969-12-31 | $7700.00 | Window Closed / Lapsed |