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US4987062A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing a silver halide emulsion

Assignee: Fujifilm Holdings Corp
•
Filing: 1989-07-05
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Granted: 1991-01-22
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Expires: 2009-07-05
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Abstract

Abstract A process for preparing a silver halide emulsion is disclosed, which comprises dissolving one or more substantially water-insoluble photographic additives in a solution of an organic solvent containing a surface active agent having a hydrophilic --SO 3 or --OSO 3 group wherein said organic solvent is an alcohol, and then adding the resulting solution to a silver halide emulsion. A small amount of a base, or small amounts of a base and an acid may optionally be present in the mixed solution of the organic solvent and the surface active agent prior to adding the one or more substantially water-insoluble photographic additives.

Inventors

  • 👤 Fumitaka Terai
  • 👤 Hiroyuki Yamagami
  • 👤 Nobuhiko Uchino
  • 👤 Masaki Okazaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 19:26
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; Y; Y10; Y10S; Y10S430/00; Y10S430/136

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 91 words
A process for preparing a silver halide emulsion, comprising the steps of dissolving one or more substantially water-insoluble photographic additives in a solution of an organic solvent containing a surface active agent having a hydrophilic -SO 3 or -OSO 3 group and a small amount of a base, or small amounts of a base and an acid present in the solution prior to addition of the one or more substantially water-insoluble photographic additives wherein said organic solvent is an alcohol, and then adding the resulting solution to a silver halide emulsion.
Claim 2
Dependent Claim 91 words
A process for preparing a silver halide emulsion, comprising the steps of dissolving one or more substantially water-insoluble photographic additives in a solution of an organic solvent containing a surface active agent having a hydrophilic -SO 3 or -OSO 3 group and a small amount of a base, or small amounts of a base and an acid present in the solution prior to addition of the one or more substantially water-insoluble photographic additives wherein said organic solvent is an alcohol, and then adding the resulting solution to a silver halide emulsion.
Claim 3
Dependent Claim 19 words
A process as in claim 1, wherein said substantially water-insoluble photographic additive is a photographic spectral sensitizing cyanine dye.
Claim 4
Dependent Claim 19 words
A process as in claim 1, wherein said organic solvent is an aromatic primary alcohol or a halogenated alcohol.
Claim 5
Dependent Claim 34 words
A process as in claim 1, wherein the amount of said surface active agent present in the solution is 25 to 100 wt% based on the amount of the one or more photographic additives.

References Cited (Backward Citations)

US3822135A Cited
US3837863A Cited
US4193801A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-01-21 1994-07-23 1995-01-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-01-21 1998-07-23 1999-01-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-01-21 2002-07-23 2003-01-22 $7700.00 Window Closed / Lapsed

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