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US2828204A Expired / Lapsed US ⏱️ 0.0 years remaining

Polyvinyl acetal silver halide emulsion containing polyvinyl acetal color formers

Assignee: EIDP Inc
•
Filing: 1953-06-23
•
Granted: 1958-03-25
•
Expires: 1973-06-23
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Abstract

No abstract record available.

Inventors

  • 👤 Taylor James Harold
  • 👤 Woodward David Willcox

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 07:54
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/32; G03C7/327; G03C7/3275

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 157 words
A PROCESS WHICH COMPRISES PRECIPITATING LIGHT-SENSITIVE SILVER HALIDES IN AN AQUEOUS SOLUTION OF A NON-COLORFORMING POLYVINYL ACETAL TAKEN FROM THE GROUP CONSISTING OF SIMPLY POLYVINYL ACETALS OF POLYVINYL ALCOHOL WITH BENZALDEHYDE AND MIXED ACETALS OF POLYVINYL ALCOHOL WITH BENZALDEHYDE AND A ALDEHYDE TAKEN FROM THE CLASS CONSISTING OF ALIPHATIC AND AROMATIC CARBOXYLIC AND SULFONIC ACIDS AND THIER WATER-SOLUBLE SALTS, THE CARBOXYLIC AND SULFONIC GROUPS BEING THE SOLE SUBSTITUENT GROUPS ATTACHED TO THE HYDROCARBON NUCLEUS OF SAID ALDEHYDES, SAID POLYVINYL ACETALS CONTAINING A LARGE NUMBER OF RECURRING INTRALINEAR -CH2-CHOH- GROUPS AND BEING HYDROPHILIC IN CHARACTER, ALLOWING THE SILVER HALIDE CRYSTALS TO RIPEN, REMOVING THE WATER-SOLUBLE SALTS, DIVIDING THE RESULTING AQUEOUS DISPERSION INTO PORTIONS, ADMIXING A DIFFERENT POLYVINYL ACETAL COLLOID COLOR FORMER CAPABLE OF FORMING UPON COLOR COUPLING DEVELOPMENT OF AN EXPOSED SILVER SALT IMAGE A DYE TAKEN FROM THE GROUP CONSISTING OF QUINONEIMINE AND AZOMETHINE DYES AND CONTAINING IN ONE OF AN ACTIVE COUPLING GROUP OF THE STRUCTURE

References Cited (Backward Citations)

US2534707A Cited
US2599494A Cited
US2606835A Cited
US2538257A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-03-24 1961-09-23 1962-03-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-03-24 1965-09-23 1966-03-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-03-24 1969-09-23 1970-03-25 $7700.00 Window Closed / Lapsed

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