US3637651A
Expired / Lapsed
US
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Ortho nitration of the phenyl diazo component of an azo compound
Assignee: Imperial Chemical Industries Ltd
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Filing: 1968-10-21
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Granted: 1972-01-25
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Expires: 1988-10-21
Abstract
Abstract MANUFACTURE OF DISPERSE MONOAZO DYESTUFFS HAVING AT LEAST ONE NITRO GROUP IN ORTHO POSITION TO THE AZO GROUP, WHICH COMPRISES TREATING THE CORRESPONDING DYESTUFF CONTAINING A HALOGEN ATOM IN ORTHO POSITION TO THE AZO GROUP WITH AN ALKALI METAL NITRITE AND A COPPER COMPOUND IN A POLAR APROTIC ORGANIC LIQUID.
Inventors
- 👤 Thomas Douglas Baron
- 👤 Brian Ribbons Fishwick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:43
CPC Classifications
C; C09; C09B; C09B43/00; C09B43/40
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) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |