Patent US2657140A successfully refreshed from Google Patents.
US2657140A
Expired / Lapsed
US
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Developer for diazotype materials
Assignee: Chemische Fabriek L Van der Grinten NV
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Filing: 1952-05-28
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Granted: 1953-10-27
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Expires: 1972-05-28
Abstract
No abstract record available.
Inventors
- 👤 Kessels Franciscus An Hubertus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:47
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/305; Y; Y10; Y10S; Y10S430/00; Y10S430/134
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
50 words
A DEVELOPER FOR DIAZOTYPE PRINTING MATERIALS COMPRISING AT LEAST ONE AZO DYESTUFF COUPLING COMPONENT, AT LEAST ONE ALKALINE METAL SALT OF A WEAK ACID AND A SMALL AMOUNT OF A SALT OF A BLUEFLUORESCENT P.P''-DIAMINOSTILBENE 0.0"DISULPHONIC ACID IN WHICH AT LEAST ONE OF THE AMINO GROUPS CARRIES A 1:3:5-TRIAZINE RING.
Claim 2
Dependent Claim
50 words
A DEVELOPER FOR DIAZOTYPE PRINTING MATERIALS COMPRISING AT LEAST ONE AZO DYESTUFF COUPLING COMPONENT, AT LEAST ONE ALKALINE METAL SALT OF A WEAK ACID AND A SMALL AMOUNT OF A SALT OF A BLUEFLUORESCENT P.P''-DIAMINOSTILBENE 0.0"DISULPHONIC ACID IN WHICH AT LEAST ONE OF THE AMINO GROUPS CARRIES A 1:3:5-TRIAZINE RING.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-10-26 | 1957-04-27 | 1957-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-10-26 | 1961-04-27 | 1961-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-10-26 | 1965-04-27 | 1965-10-27 | $7700.00 | Window Closed / Lapsed |