US2618559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stain preventing shortstop bath for photographic azine dye images
Assignee: GAF Chemicals Corp
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Filing: 1950-03-21
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Granted: 1952-11-18
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Expires: 1970-03-21
Abstract
No abstract record available.
Inventors
- 👤 Robert C Gunther
- 👤 Tulagin Vsevolod
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:38
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/3046
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
110 words
IN THE PROCESS OF PRODUCING SUBSTRACTIVLY COLORED AZINE DYE IMAGES IN A SILVER HALIDE EMULSION LAYER CONTAINING A COLOR FORMER CAPABLE OF COUPLING WITH THE OXIDATION PRODUCTS OF A 2,4 DIAMINOANILINE DEVELOPING AGENT, TO FORM AN AZINE DYE WHICH COMPRISES EXPOSING THE EMULSION AND DEVELOPING THE SAME WITH A COLOR DEVELOPER CONTAINING AS THE EFFECTIVE DEVELOPING AGENT A 2,4DIAMINO-ANILINE, THE IMPROVEMENT WHICH COMPRISES AVOIDING THE FORMATION OF STAIN AFTER THE COLOR DEVELOPMENT BY SHORTSTOPPING THE COLOR DEVELOPED EMULSION WITH AN AQUEOUS BATH HAVING A PH RANGING FROM 2 TO 4 AND CONTAINING AN ORGANIC ACID OF THE CLASS CONSISTING OF PYRUVIC ACID AND ITS B-ACYL, B-ALKYL, B-ARYL, AND B-CARBOXY-SUBSTITUTED DERIVATIVES.
Claim 2
Dependent Claim
110 words
IN THE PROCESS OF PRODUCING SUBSTRACTIVLY COLORED AZINE DYE IMAGES IN A SILVER HALIDE EMULSION LAYER CONTAINING A COLOR FORMER CAPABLE OF COUPLING WITH THE OXIDATION PRODUCTS OF A 2,4 DIAMINOANILINE DEVELOPING AGENT, TO FORM AN AZINE DYE WHICH COMPRISES EXPOSING THE EMULSION AND DEVELOPING THE SAME WITH A COLOR DEVELOPER CONTAINING AS THE EFFECTIVE DEVELOPING AGENT A 2,4DIAMINO-ANILINE, THE IMPROVEMENT WHICH COMPRISES AVOIDING THE FORMATION OF STAIN AFTER THE COLOR DEVELOPMENT BY SHORTSTOPPING THE COLOR DEVELOPED EMULSION WITH AN AQUEOUS BATH HAVING A PH RANGING FROM 2 TO 4 AND CONTAINING AN ORGANIC ACID OF THE CLASS CONSISTING OF PYRUVIC ACID AND ITS B-ACYL, B-ALKYL, B-ARYL, AND B-CARBOXY-SUBSTITUTED DERIVATIVES.
References Cited (Backward Citations)
US2440954A
Cited
US2486440A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-11-18 | 1956-05-19 | 1956-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-18 | 1960-05-19 | 1960-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-18 | 1964-05-19 | 1964-11-18 | $7700.00 | Window Closed / Lapsed |