US3894012A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of oxazine dye
Assignee: BASF SE
•
Filing: 1973-02-07
•
Granted: 1975-07-08
•
Expires: 1993-02-07
Abstract
Abstract An improved process for the production of oxazine dyes by condensation of a meta-aminophenol and a 3-alkoxy-4-nitroso-Nsubstituted aniline comprising the addition of a Lewis acid and a base in the condensation step.
Inventors
- 👤 Hans Baumann
- 👤 Udo Mayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:41
CPC Classifications
C; C09; C09B; C09B19/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
14 words
IN THE PROCESS FOR THE PRODUCTION OF AN OXAZINE DYE OF THE FORMULA (I),
Claim 2
Dependent Claim
14 words
IN THE PROCESS FOR THE PRODUCTION OF AN OXAZINE DYE OF THE FORMULA (I),
Claim 3
Dependent Claim
14 words
A process as claimed in claim 1 wherein the Lewis acid is zinc chloride.
References Cited (Backward Citations)
US3629248A
Cited
US3655601A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |