Eastman-kodak Company

Sang H Kim

Allen K Tsaur

Mamie Kam-Ng

David P Hamblen

Thomas R Dobles

Jacob I Cohen

John D Baloga

Clyde P Glover

George H Hawks, Iii

Richard A Demauriac

Spencer Alan Pugh

Richard L Parton

Anthony Adin

Kenneth Joseph Reed

Steven G Link

Paul B Gilman, Jr

Jerzy A Budz

David A Stegman

Thomas Joseph Dannhauser

George J Burgmaier

Arlyce T Bowne

Mark A Whitson

Richard E Beal

Wai K Lam

Bradley K Jensen

David A Dumont

Charles J Battaglia

Richard W Spayd

Hao-jan Chang

Denise S Secord

Silver halide emulsions precipitated in the presence of ortho-substituted water-soluble disulfides

This invention provides a color silver halide photographic element comprising a support having situated thereon a red light-sensitive, cyan dye-forming unit; a green light-sensitive, magenta dye-forming unit; and a blue light-sensitive, yellow dye-forming unit. The photographic element further comprising a first layer and a second layer, the second layer being a layer which provides a site of development for solution physical development.

Color photographic element with improved contrast

This invention provides color silver halide photographic element comprising a red light-sensitive, cyan dye-forming unit comprising a photosensitive silver halide emulsion layer and an image dye-forming coupler; a green light-sensitive, magenta dye-forming unit comprising a photosensitive silver halide emulsion layer and an image dye-forming coupler; and a blue light-sensitive, yellow dye-forming unit comprising a photosensitive silver halide emulsion layer and an image dye-forming coupler; the photographic element further comprising a first layer and a second layer, the second layer being a layer which provides a site of development for solution physical development; wherein at least one of the dye-forming units comprises two or more emulsion layers spectrally sensitized to the same region of the visible spectrum, but exhibiting different photographic sensitivities and wherein the first layer is positioned adjacent to the layer containing the slowest emulsion of said dye-forming unit and between the layer containing the slowest emulsion and the second layer. Preferably the photographic element is a color reversal photographic element.

Color photographic element with improved push processing

This invention provides a color silver halide photographic element comprising a support having situated thereon a red light-sensitive, cyan dye-forming unit comprising a photosensitive silver halide emulsion layer and an image dye-forming coupler; a green light-sensitive, magenta dye-forming unit comprising a photosensitive silver halide emulsion layer and an image dye-forming coupler; and a blue light-sensitive, yellow dye-forming unit comprising a photosensitive silver halide emulsion layer and an image dye-forming coupler; wherein at least one of the dye-forming units comprises two or more emulsion layers spectrally sensitized to the same region of the visible spectrum, but exhibiting different photographic sensitivities, each such emulsion layer containing an image dye-forming coupler wherein at least one, but not all, of the emulsion layers of the dye-forming unit contains the hydrolyzed or unhydrolyzed form of a benzazolium compound represented by formula (I): ##STR1##

Color photographic element containing benzazolium compounds

A supersensitizing dye combination for silver halide photographic materials is disclosed. The combination is of a first dye according to the formula: ##STR1## Z.sub.1 and Z.sub.2 each independently represents the atoms necessary to complete a substituted or unsubstituted heterocyclic nucleus,

Sensitizing dye combination for photographic materials

The invention provides a method of forming a spectrally sensitized emulsion comprising providing a silver bromoiodide emulsion, adding sensitizing dye ##STR1## X.sup.+ is a cation other than N-alkyl pyridinium, adding an N-alkyl pyridinium salt, and completing the heat cycle for sensitization.

Silver halide emulsions spectrally sensitized in the presence of low

The invention relates to an emulsion comprising silver halide grains said grains comprising sensitizing dyes adsorbed onto said grains during grain forming or sensitizing and at least one sulfodihydroxy aryl compound represented by the Fomulas I or II ##STR1## wherein X and Y represent an SO.sub.3 group or a hydrogen with at least one of X and Y being a sulfo group.

Silver halide photographic emulsions prepared and sensitized in the

A photographic element which has a blue sensitive emulsion with broad blue spectral coverage and yet, good speed and low fog. The element has a blue sensitive silver halide tabular grain emulsion which has a tabularity of at least 25 sensitized with a dye of formula (I) and a dye of formula (II), wherein the formula (I) dye on the emulsion has a peak sensitization of between 400-445 nm and the formula (II) dye on the emulsion has a peak sensitization of between 446-500 nm: ##STR1## wherein: Z.sub.1, Z.sub.2, Z.sub.3 and Z.sub.4 independently represent the atoms necessary to complete a substituted or unsubstituted benzene or naphthylene;

Photographic elements containing particular blue sensitized tabular

This invention provides a method of preparing a silver halide photographic emulsion which comprises adding to the silver halide emulsion before or during precipitation a non-labile chalcogen compound represented by Formula I:

Silver halide photographic emulsions precipitated in the presence of

A silver halide photographic element having a green sensitive layer the silver halide of which is sensitized by a combination of three sensitizing dyes of the formula I, II and III: ##STR1## wherein: each of the benzo-rings of I, II or III may be substituted or unsubstituted;

Green sensitized silver halide emulsions

A multicolor photographic element capable of forming a viewable reversal dye image is disclosed comprising a support and, coated on the support, a blue recording yellow dye image forming layer unit, a green recording magenta dye image forming layer unit, and a red recording cyan dye image forming layer unit, each of the layer units containing in at least one layer a silver halide emulsion having a grain halide content of from 0 to 5 mole percent chloride, from. 0.5 to 20 mole percent iodide, and from 80 to 99.5 mole percent bromide, based on total silver. The photographic element is characterized in that at least one of the silver halide emulsion layers is a tabular grain emulsion layer in which the coefficient of variation of the tabular grain emulsion is less than 15 percent, based on the total grain population of the emulsion, and the total grain population of the tabular emulsion consists essentially of tabular grains having a mean thickness of less than 0.3 .mu.m and a mean tabularity of greater than 25.

Reversal photographic elements containing tabular grain emulsions

A process is disclosed of accelerating the preparation of a photographic emulsion containing tabular silver halide grains exhibiting a reduced degree of total grain dispersity. A dispersing medium is provided containing bromide ions, and a population of silver halide grain nuclei containing parallel twin planes is formed in the dispersing medium. A portion of the grain nuclei are ripened out, and then the silver halide grain nuclei containing parallel twin planes remaining are grown to form tabular silver halide grains. A polyalkylene oxide containing both hydrophilic and lipophilic block units is selected from among those known to be capable of reducing total grain dispersity when present during nucleation. However, in this process precipitation is accelerated while maintaining low dispersity of the total grain population by forming twin planes in the grain nuclei within the pAg and temperature boundaries of Curve A in FIG. 1 and by delaying introduction of the polyalkylene oxide block copolymer surfactant until after the silver halide nuclei containing twin planes have been formed.

Process for accelerating the precipitation of a low coefficient of

A multicolor photographic element capable of forming a viewable reversal dye image is disclosed comprising a support and, coated on the support, a blue recording yellow dye image forming layer unit, a green recording magenta dye image forming layer unit, and a red recording cyan dye image forming layer unit, each of the dye image forming layer units containing at least one silver halide emulsion layer comprised of a vehicle and silver halide grains having (1) a halide content of from 0 to 5 mole percent chloride, from 0.1 to 20 mole percent iodide, and from 80 to 99.9 mole percent bromide, based on total silver. At least one of the silver halide emulsion layers in one of the layer units positioned to receive exposing radiation prior to at least one of the green or red recording layer units is a tabular grain emulsion layer in which a polyalkylene oxide block copolymer is present selected to allow the preparation of tabular grains having a mean thickness of less than 0.3 .mu.m and a mean tabularity of greater than 25, accounting for greater than 97 percent of the total projected area of grains having an equivalent circular diameter of at least 0.2 .mu.m.

Tabular grain emulsion containing reversal photographic elements

A method for forming a photographic element includes steps of heating an emulsion containing grains of a radiation sensitive silver haloiodide to form a first melt, heating an emulsion containing grains of a silver salt effective to enhance the photographic properties of the silver haloiodide emulsion to form a second melt, and coating the first and second melts onto a photographic support to form an image recording layer. The silver salt grains are substantially insensitive to radiation at wavelengths at which said silver haloiodide grains are sensitive. The coating step is preferably carried out by blending the first and second melts together, then immediately coating the silver haloiodide emulsion onto the support. In a preferred embodiment, the silver salt is essentially silver chloride in the form of relatively fine cubic grains, and the silver haloiodide is in the form of tabular grains larger than the cubic grains. The foregoing procedure unexpectedly improves the speed of the resulting photographic element. For color reversal photographic elements, the melt containing the fine silver salt grains is conveniently the coupler melt.

Method of forming a silver haloiodide photographic element

The low intensity reciprocity failure characteristics of a silver halide emulsion are improved, without significant reduction of high intensity speed, by incorporating iridium ion into the silver halide grains after or toward the end of the precipitation of the grains in such a way that iridium is below the surface of the grains.

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Pittsford, NY, United States of America

Sang H Kim