Patent US4987062A successfully refreshed from Google Patents.
US4987062A
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Process for preparing a silver halide emulsion
Assignee: Fujifilm Holdings Corp
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Filing: 1989-07-05
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Granted: 1991-01-22
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Expires: 2009-07-05
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 19:40
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)
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 |