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US4490458A Expired / Lapsed US ⏱️ 0.0 years remaining

Multicolor photographic elements containing silver iodide grains

Assignee: Eastman Kodak Co
•
Filing: 1983-10-19
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Granted: 1984-12-25
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Expires: 2003-10-19
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Abstract

Abstract Multicolor photographic elements are disclosed each containing superimposed emulsion layers for separately recording blue and minus blue light including at least one emulsion layer comprised of a dispersing medium and silver halide grains, wherein at least 50 percent of the total projected area of the silver halide grains is provided by thin tabular silver iodide grains having a thickness of less than 0.3 micron and an average aspect ratio of greater than 8:1. The multicolor photographic elements show advantages in the minus blue recording emulsion layers directly attributable to the thin tabular silver iodide grains.

Inventors

  • 👤 Gary L. House

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:28
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/3022

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 90 words
In a photographic element capable of producing a multicolor image comprised of a support and, located on said support, superimposed emulsion layers for facilitating separate recording of blue, green, and red light, each comprised of a dispersing medium and silver halide grains, the improvement comprising at least 50 percent of the total projected area of said silver halide grains in at least one emulsion layer being provided by thin tabular silver iodide grains having a thickness of less than 0.3 micron and an average aspect ratio of greater than 8:1.
Claim 2
Dependent Claim 90 words
In a photographic element capable of producing a multicolor image comprised of a support and, located on said support, superimposed emulsion layers for facilitating separate recording of blue, green, and red light, each comprised of a dispersing medium and silver halide grains, the improvement comprising at least 50 percent of the total projected area of said silver halide grains in at least one emulsion layer being provided by thin tabular silver iodide grains having a thickness of less than 0.3 micron and an average aspect ratio of greater than 8:1.
Claim 3
Dependent Claim 18 words
A photographic element according to claim 1 wherein said one emulsion layer is a blue recording element layer.
Claim 4
Dependent Claim 22 words
A photographic element according to claim 1 wherein said tabular silver iodide grains have an average aspect ratio of at least 12:1.
Claim 5
Dependent Claim 36 words
A photographic element 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 in said one blue recording emulsion layer.
Claim 6
Dependent Claim 19 words
A photographic element according to claim 1 wherein silver salt is epitaxially located on said tabular silver iodide grains.
Claim 7
Dependent Claim 17 words
A photographic element according to claim 5 wherein said silver salt is comprised of a silver halide.
Claim 8
Dependent Claim 16 words
A photographic element according to claim 6 wherein said silver salt is comprised of silver chloride.
Claim 9
Dependent Claim 16 words
A photographic element according to claim 6 wherein said silver salt is comprised of silver bromide.
Claim 10
Dependent Claim 36 words
A photographic element according to claim 4 wherein said silver salt is epitaxially located on less than 25 percent of the total surface area provided by the major crystal faces of said tabular silver iodide grains.
Claim 11
Dependent Claim 36 words
A photographic element according to claim 9 wherein said silver salt is epitaxially located on less than 10 percent of the total surface area provided by the major crystal faces of said tabular silver iodide grains.
Claim 12
Dependent Claim 21 words
A photographic element according to claim 1 wherein said tabular silver iodide grains have an average thickness greater than 0.005 micron.
Claim 13
Dependent Claim 22 words
A photographic element according to claim 1 wherein said tabular silver iodide grains have an average thickness greater than 0 01 micron.
Claim 14
Dependent Claim 43 words
A photographic element according to claim 2 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 15
Dependent Claim 21 words
A photographic element according to claim 1 wherein said tabular silver iodide grains have an average thickness greater than 0.1 micron.
Claim 16
Dependent Claim 21 words
A photographic element according to claim 14 wherein said tabular silver iodide grains have an average thickness greater than 0.15 micron.
Claim 17
Dependent Claim 27 words
A photographic element according to claim 1 wherein said tabular silver iodide grains are positioned to receive exposing radiation prior to remaining of said silver halide grains.
Claim 18
Dependent Claim 34 words
A photographic element according to claim 1 wherein said tabular silver iodide grains are positioned to receive exposing radiation prior to said silver halide grains present in said red and green recording emulsion layers.
Claim 19
Dependent Claim 47 words
A photographic element according to claim 1 wherein said red and green recording emulsion layers are comprised of high average aspect ratio tabular grain emulsions and are positioned to receive exposing radiation prior to said tabular silver iodide grains and said support is a white reflective support.
Claim 20
Dependent Claim 36 words
A process of producing a multicolor photographic image comprising processing in an aqueous alkaline solution in the presence of a developing agent an imagewise exposed photographic element according to any one of claims 1 through 18.

References Cited (Backward Citations)

DE505012C Cited
US4094684A Cited
US4142900A Cited
GB2053499A Cited
US4435501A Cited
US4439520A Cited
US4459353A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-12-25 1988-06-25 1988-12-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-12-25 1992-06-25 1992-12-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-12-25 1996-06-25 1996-12-25 $7700.00 Window Closed / Lapsed

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