US2799692A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nu-acylation of p-aminophenols
Assignee: Bayer Corp
•
Filing: 1955-06-24
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Granted: 1957-07-16
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Expires: 1975-06-24
Abstract
No abstract record available.
Inventors
- 👤 Willard J Croxall
- 👤 Mirza John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:04
CPC Classifications
C; C07; C07C; C07C233/00; C07C233/01; C07C233/16
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
66 words
IN THE N-ACYLATION OF A P-AMINOPHENOL BY CONDENSATION WITH A HIGH FATTY ACID, THE IMPROVEMENT WHICH COMPRISES PLACING THE REACTION MIXTURE OF P-AMINOPHENOL AND ACID IN AN ATMOSPHERE OF SULFUR DIOXIDE, HEATING SAID REACTION MIXTURE TO REMOVE THE WATER OF CONDENATION, COOLING TO CRYSTALLIZE THE N-ACYL-P-AMINOPHENOL AND WASHING THE RESULTING CRYSTALLINE PRODUCT, SAID HEATING, COOLING AND WASHING BEING DONE WHILE MAINTAINING SAID ATMOSPHERE OF SULFUR DIOXIDE.
References Cited (Backward Citations)
US2625557A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-07-15 | 1961-01-14 | 1961-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-15 | 1965-01-14 | 1965-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-15 | 1969-01-14 | 1969-07-16 | $7700.00 | Window Closed / Lapsed |