Patent US3649286A successfully refreshed from Google Patents.
US3649286A
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Process for spectrally sensitizing photographic silver halide emulsions
Assignee: Eastman Kodak Co
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Filing: 1968-09-23
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Granted: 1972-03-14
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Expires: 1988-09-23
Abstract
Abstract A process for spectrally sensitizing photographic silver halide which comprises: adsorbing a photographic spectral sensitizing dye onto finely divided silica particles; and adding the dyed silica particles to a liquid photographic silver halide emulsion.
Inventors
- 👤 Roberta A Ogilvie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:32
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/08; G03C1/10; G03C1/102
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
22 words
The process in accordance with claim 1 wherein said silica particles have an average diameter of from about 0.001 to 10 microns.
Claim 2
Dependent Claim
46 words
The process in accordance with claim 1 wherein said dye and said silica particles are present in proportions of about from 0.001 to 0.200 gram of said dye and about from 10 to 150 grams of said silica per gram-mole of silver halide in said emulsion.
Claim 3
Dependent Claim
20 words
the process in accordance with claim 3 wherein the photographic silver halide emulsion is an aqueous gelatin silver halide emulsion.
Claim 4
Dependent Claim
26 words
The process in accordance with claim 1 wherein said spectral sensitizing dye is selected from the group consisting of a cyanine dye and a merocyanine dye.
Claim 5
Dependent Claim
73 words
A process for spectrally sensitizing photographic silver halide which comprises: dissolving a photographic spectral sensitizing dye in an organic solvent; mixing finely divided silica particles with a solution of dye in organic solvent to adsorb the dye onto the silica particles; removing the organic solvent; and, adding the dyed silica particles to a liquid photographic silver halide emulsion to transfer dye from the silica particles to the silver halide grains in said emulsion.
Claim 6
Dependent Claim
22 words
The process in accordance with claim 6, wherein said silica particles have an average diameter of from about 0.001 to 10 microns.
Claim 7
Dependent Claim
47 words
The process in accordance with claim 6 wherein said dye and said silica particles are present in the proportions of about from 0.001 to 0.200 gram of said dye and about from 10 to 150 grams of said silica per gram-mole of silver halide in said emulsion.
Claim 8
Dependent Claim
20 words
The process in accordance with claim 8 wherein the photographic silver halide emulsion is an aqueous gelatin silver halide emulsion.
Claim 9
Dependent Claim
21 words
The process in accordance with claim 3 wherein said silica particles comprise colloidal silica and said dye is a 1,1''-diethyl-2,2''-cyanine salt.
Claim 10
Dependent Claim
22 words
The process in accordance with claim 3 wherein said silica particles comprise colloidal silica and said dye is anhydro-5,5'', 6,6''-tetrachloro-1,1''-diethyl-3,3''-di(3-sulfobutyl) -benzimidazolocarbocyanine hydroxide.
Claim 11
Dependent Claim
20 words
The process in accordance with claim 3 wherein said silica particles comprise colloidal silica and said dye is 3-(3-dimethylaminopropyl)-5- -2-thio-2,4-oxazolidinedione.
Claim 12
Dependent Claim
12 words
A photographic silver halide emulsion prepared by the process of claim 1.
Claim 13
Dependent Claim
23 words
A photographic element comprising a support having thereon a layer containing a photographic silver halide emulsion prepared by the process of claim 1.
References Cited (Backward Citations)
US3469987A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-14 | 1975-09-13 | 1976-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-14 | 1979-09-13 | 1980-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-14 | 1983-09-13 | 1984-03-14 | $7700.00 | Window Closed / Lapsed |