US3676138A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formation of dyes suited for reproduction purposes
Assignee: Agfa Gevaert NV
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Filing: 1970-12-02
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Granted: 1972-07-11
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Expires: 1990-12-02
Abstract
Abstract DIAZO RECORDING PROCESS GIVING A NEUTRAL BLACK TONE USING AS THE COUPLING AGENT IN AN ALKALINE MEDIUM A QUATERNARY SALT OF 2-METHYL-5,6-DIMETHOXYBENZOTHIAZOLE OR A QUATERNARY SALT OF 2-METHYLBENZOTHIAZOLE WHEREIN THE CARBON ATOMS OF THE 5- AND 6-POSITION ARE PART OF A FUSED RING CLOSED BY A -O-CH2-O- OR A -O-CH2-CH2-0- GROUP. PREFERABLY THE QUATERNARY SALT IS SUBSTITUTED ON THE NITROGEN ATOM OF THE BENZTHIAZOLIUM NUCLEUS WITH A -CH2-Y GROUP IN WHICH Y IS AN ELECTRON-WITHDRAWING GROUP SUCH AS IN A -CH2-CO-NH-SO2-CH3 GROUP; AND RECORDING MATERIALS USEFUL THEREIN.
Inventors
- 👤 Albert Lucien Poot
- 👤 Henri Depoorter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:57
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/52; G03C1/58
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) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |