US3681320A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of disazo j acid urea dyestuffs
Assignee: EIDP Inc
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Filing: 1970-01-13
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Granted: 1972-08-01
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Expires: 1990-01-13
Abstract
Abstract PREPARATION OF STORAGE-STABLE AQUEOUS SOLUTIONS CONTAINING 10-25 WEIGHT PRECENT OF A DISAZO J ACID UREA DYE BY COUPLING AN ARYL DIAZONIUM SALT, FOR EXAMPLE, A SALT FROM BROENNER''S ACID, AND J ACID UREA, AT A MOLAR RATIO OF ABOUT 2:1, IN AN AQUEOUS MEDIUM, AT A PH OF ABOUT 3-9, AT A TEMPERATURE OF ABOUT 0-65*C., IN THE PRESENCE OF TRIETHANOLAMINE AS THE ACID ACCEPTOR.
Inventors
- 👤 Richard C Franklin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:07
CPC Classifications
C; C09; C09B; C09B33/00; C09B33/02; C09B33/08; C09B33/10; C09B41/00
Claims Analysis
Total Claims: 0
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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) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |