Patent US3917987A successfully refreshed from Google Patents.
US3577404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Basic pyrazolone monoazo dyes containing an ammonium or hydrazinium group
Assignee: Sandoz AG
•
Filing: 1968-07-23
•
Granted: 1971-05-04
•
Expires: 1988-07-23
Abstract
Abstract 1-((+)K-Y-Z-),4-(K1-N=N-)-BENZENE A(-) BASIC DYES OF THE FORMULA WHEREIN K1 STANDS FOR A COUPLING COMPOUND OF TH PYRAZOLONE SERIES, Y STANDS FOR AN ALKYLENE OR ARYLENE RADICAL, Z STANDS FOR -O-, -S- OR -SO2-, K$ STANDS FOR A HYDRAZINIUM- OR AN AMMONIUM GROUP AND WHEREIN THE RING B MAY HEAR FURTHER SUBSTITUENTS; ARE USEFUL FOR DYEING ACRYLONITRILE POLYMERS AND COPOLYMERS. RESULTING DYEINGS HAVE GOOD FASTNESS PROPERTIES.
Inventors
- 👤 Roland Entschel
- 👤 Willy Steinemann
- 👤 Curt Mueller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:21
CPC Classifications
C; C09; C09B; C09B44/00; C09B44/02; C09B44/08
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |