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US4459353A Expired / Lapsed US ⏱️ 0.0 years remaining

Gamma phase silver iodide emulsions, photographic elements containing these emulsions, and processes for their use

Assignee: Eastman Kodak Co
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Filing: 1982-12-20
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Granted: 1984-07-10
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Expires: 2002-12-20
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Abstract

Abstract A silver halide emulsion is disclosed comprised of thin tabular silver iodide grains of a face centered cubic crystal structure. These tabular grains have a high average aspect ratio and account for at least 50 percent of the total projected area of the silver halide grains present in the emulsion. The emulsions are useful in blue recording as well as other layers of photographic elements.

Inventors

  • 👤 Joe E. Maskasky

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 23:28
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/0051; G03C1/06; G03C1/07; G03C1/08; G03C1/09; G03C1/10; G03C1/12; G03C1/14; G03C1/16; G03C1/18; G03C1/22; G03C1/24; G03C1/035; G03C2001/03517; G03C2001/03523; G03C2001/03552

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 64 words
A high aspect ratio tabular grain silver halide emulsion comprised of a dispersing medium and silver halide grains, wherein at least 50 percent of the total projected area of said silver halide grains is provided by tabular silver iodide grains of a face centered cubic crystal structure having a thickness of less than 0.3 micron and an average aspect ratio of greater than 8:1.
Claim 2
Dependent Claim 64 words
A high aspect ratio tabular grain silver halide emulsion comprised of a dispersing medium and silver halide grains, wherein at least 50 percent of the total projected area of said silver halide grains is provided by tabular silver iodide grains of a face centered cubic crystal structure having a thickness of less than 0.3 micron and an average aspect ratio of greater than 8:1.
Claim 3
Dependent Claim 21 words
An emulsion according to claim 1 wherein said tabular silver iodide grains have an average aspect ratio of at least 12:1.
Claim 4
Dependent Claim 13 words
An emulsion according to claim 1 wherein said dispersing medium is a peptizer.
Claim 5
Dependent Claim 15 words
An emulsion according to claim 3 wherein said peptizer is gelatin or a gelatin derivative.
Claim 6
Dependent Claim 28 words
An emulsion according to claim 1 wherein said tabular silver iodide grains account for at least 70 percent of the total projected area of said silver halide grains.
Claim 7
Dependent Claim 18 words
An emulsion according to claim 1 wherein silver salt is epitaxially located on said tabular silver iodide grains.
Claim 8
Dependent Claim 14 words
An emulsion according to claim 6 wherein said silver salt is a silver halide.
Claim 9
Dependent Claim 15 words
An emulsion according to claim 7 wherein said silver salt is comprised of silver chloride.
Claim 10
Dependent Claim 15 words
An emulsion according to claim 7 wherein said silver salt is comprised of silver bromide.
Claim 11
Dependent Claim 15 words
An emulsion according to claim 6 wherein said silver salt is comprised of silver thiocyanate.
Claim 12
Dependent Claim 34 words
An emulsion according to claim 6 wherein said silver salt is epitaxially located on less than 25 percent of the surface area provided by the major crystal faces of said tabular silver iodide grains.
Claim 13
Dependent Claim 34 words
An emulsion according to claim 11 wherein said silver salt is epitaxially located on less than 10 percent of the surface area provided by the major crystal faces of said tabular silver iodide grains.
Claim 14
Dependent Claim 26 words
An emulsion according to claim 6 wherein at least one of said silver salt and said tabular silver iodide grains contains a sensitivity modifier incorporated therein.
Claim 15
Dependent Claim 14 words
An emulsion according to claim 13 wherein said silver salt contains iridium incorporated therein.
Claim 16
Dependent Claim 21 words
An emulsion according to claim 1 wherein said tabular silver iodide grains have an average thickness of greater than 0.005 micron.
Claim 17
Dependent Claim 21 words
An emulsion according to claim 1 wherein said tabular silver iodide grains have an average thickness of greater than 0.01 micron.
Claim 18
Dependent Claim 42 words
An emulsion according to claim 1 wherein said tabular silver iodide grains have an average thickness of less than 0.1 micron and said emulsion additionally contains a blue spectral sensitizing dye having an absorption peak of a wavelength longer than 430 nanometers.
Claim 19
Dependent Claim 24 words
An emulsion according to claim 1 wherein said emulsion is a high resolution emulsion having an average grain diameter of less than 0.2 micron.
Claim 20
Dependent Claim 35 words
In a photographic element comprised of a support and at least one radiation-sensitive emulsion layer, the improvement wherein said emulsion layer is comprised of an emulsion according to any one of claims 1 through 18.
Claim 21
Dependent Claim 31 words
A process of producing a visible photographic image comprising processing in an aqueous alkaline solution in the presence of a developing agent an imagewise exposed photographic element according to claim 19.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-07-10 1988-01-09 1988-07-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-07-10 1992-01-09 1992-07-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-07-10 1996-01-09 1996-07-10 $7700.00 Window Closed / Lapsed

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