WO1994022054A1 - Elements photographiques formant une image couleur - Google Patents

Elements photographiques formant une image couleur Download PDF

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Publication number
WO1994022054A1
WO1994022054A1 PCT/US1993/002604 US9302604W WO9422054A1 WO 1994022054 A1 WO1994022054 A1 WO 1994022054A1 US 9302604 W US9302604 W US 9302604W WO 9422054 A1 WO9422054 A1 WO 9422054A1
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WIPO (PCT)
Prior art keywords
emulsion
layer
grain
sensitized
tabular
Prior art date
Application number
PCT/US1993/002604
Other languages
English (en)
Inventor
Richard Peter Szajewski
Gary Lawrence House
Thomas Brownell Brust
Joe Edward Maskasky
Debra Lynn Hartsell
Donald Lee Black
James Parker Merrill
Anne Elizabeth Bohan
Original Assignee
Eastman Kodak Company
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Filing date
Publication date
Application filed by Eastman Kodak Company filed Critical Eastman Kodak Company
Priority to EP93907625A priority Critical patent/EP0641459B1/fr
Priority to JP52097094A priority patent/JP3333518B2/ja
Priority to PCT/US1993/002604 priority patent/WO1994022054A1/fr
Priority to DE69326000T priority patent/DE69326000T2/de
Publication of WO1994022054A1 publication Critical patent/WO1994022054A1/fr

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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/3022—Materials with specific emulsion characteristics, e.g. thickness of the layers, silver content, shape of AgX grains
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/0051—Tabular grain emulsions
    • G03C1/0053—Tabular grain emulsions with high content of silver chloride
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/10—Organic substances
    • G03C1/12—Methine and polymethine dyes
    • G03C1/14—Methine and polymethine dyes with an odd number of CH groups
    • G03C1/16—Methine and polymethine dyes with an odd number of CH groups with one CH group
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/10—Organic substances
    • G03C1/12—Methine and polymethine dyes
    • G03C1/14—Methine and polymethine dyes with an odd number of CH groups
    • G03C1/18—Methine and polymethine dyes with an odd number of CH groups with three CH groups
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/10—Organic substances
    • G03C1/12—Methine and polymethine dyes
    • G03C1/22—Methine and polymethine dyes with an even number of CH groups
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/0051—Tabular grain emulsions
    • G03C2001/0055—Aspect ratio of tabular grains in general; High aspect ratio; Intermediate aspect ratio; Low aspect ratio
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/035—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein characterised by the crystal form or composition, e.g. mixed grain
    • G03C2001/03558—Iodide content
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/035—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein characterised by the crystal form or composition, e.g. mixed grain
    • G03C2001/03594—Size of the grains
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C2200/00—Details
    • G03C2200/01—100 crystal face
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C2200/00—Details
    • G03C2200/11—Blue-sensitive layer
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C2200/00—Details
    • G03C2200/53—Red-sensitive layer
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/305—Substances liberating photographically active agents, e.g. development-inhibiting releasing couplers
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/305—Substances liberating photographically active agents, e.g. development-inhibiting releasing couplers
    • G03C7/30541—Substances liberating photographically active agents, e.g. development-inhibiting releasing couplers characterised by the released group

Definitions

  • the invention relates to color photographic elements comprising radiation sensitive tabular grain silver halide emulsion layers.
  • An emulsion is generally understood to be a "tabular grain emulsion" when tabular grains account for at least 50 percent of total grain projected area.
  • a grain is generally considered to be a tabular grain when the ratio of its equivalent circular diameter (ECD) to its thickness (t) is at least 2.
  • the equivalent circular diameter of a grain is the diameter of a circle having an area equal to the projected area of the grain.
  • intermediate aspect ratio tabular grain emulsion refers to an emulsion which has an average tabular grain aspect ratio in the range of from 5 to 8.
  • the term “high aspect ratio tabular grain emulsion” refers to an emulsion which has an average tabular grain apsect ratio of greater than 8.
  • thin tabular grain is generally understood to be a tabular grain having a thickness of less than 0.2 m.
  • ultrathin tabular grain is generally understood to be a tabular grain having a thickness of 0.06 m or less.
  • high chloride refers to grains that contain at least 50 mole percent chloride based on silver. In referring to grains of mixed halide content, the halides are named in order of increasing molar concentrations—e.g., silver iodochloride contains a higher molar concentration of chloride than iodide.
  • tabular grain emulsions contain tabular grains that are irregular octahedral grains.
  • Regular octahedral grains contain eight identical crystal faces, each lying in a different ⁇ 111 ⁇ crystallographic plane.
  • octahedra contain two or more parallel twin planes that separate two major grain faces lying in ⁇ 111 ⁇
  • silver chloride grains prefer to form regular cubic grains—that is, grains bounded by six identical ⁇ 100 ⁇ crystal faces. Tabular grains bounded by ⁇ 111 ⁇ faces in silver chloride emulsions often revert to nontabular forms unless morphologically stabilized. While tabular grain silver bromide emulsions were known to the art long before the 1980's, Wey U.S. Patent 4,399,215 produced the first tabular grain silver chloride emulsion. The tabular grains were of the twinned type, exhibiting major faces of threefold
  • the thicknesses of the tabular grains were high compared to contemporaneous silver bromide and bromoiodide tabular grain emulsions because the ammonia ripening agent thickened the tabular grains. To achieve ammonia ripening it was also necessary to precipitate the emulsions at a relatively high pH, which is known to produce elevated minimum densities (fog) in high chloride emulsions. Further, to avoid degrading the tabular grain geometries sought both bromide and iodide ions were excluded from the tabular grains early in their
  • Maskasky U.S. Patent 4,400,463 developed a strategy for preparing a high chloride emulsion containing tabular grains with parallel twin planes and ⁇ 111 ⁇ major crystal faces with the significant advantage of tolerating significant internal inclusions of the other halides.
  • the strategy was to use a particularly selected synthetic polymeric peptizer in combination with a grain growth modifier having as its function to promote the formation of ⁇ 111 ⁇ crystal faces.
  • Adsorbed aminoazaindenes, preferably adenine, and iodide ions were disclosed to be useful grain growth modifiers.
  • Maskasky U.S. Patent 4,713,323 significantly advanced the state of the art by preparing high chloride emulsions
  • oxidizing agent or alkylating agent, King et al U.S.
  • Patent 4,942,120 Maskasky II placed within reach of the art high chloride tabular grain emulsions with
  • 4,983,508 employed organic bis-quaternary amine salts.
  • Bogg U.S. Patent 4,063,951 reported the first tabular grain emulsions in which the tabular grains had parallel ⁇ 100 ⁇ major crystal faces.
  • the tabular grains of Bogg exhibited square or rectangular major faces, thus lacking the threefold symmetry of conventional tabular grain ⁇ 111 ⁇ major crystal faces.
  • Bogg employed an ammoniacal ripening process for preparing silver bromoiodide tabular grains having aspect ratios ranging from 4:1 to 1:1.
  • the average aspect ratio of the emulsion was reported to be 2, with the highest aspect ratio grain (grain A in Figure 3) being only 4.
  • Bogg states that the emulsions can contain no more than 1 percent iodide and demonstrates only a 99.5% bromide 0.5% iodide emulsion. Attempts to prepare tabular grain emulsions by the procedures of Bogg have been
  • Mignot U.S. Patent 4,386,156 represents an improvement over Bogg in that the disadvantages of ammoniacal ripening were avoided in preparing a silver bromide emulsion containing tabular grains with square and rectangular major faces. Mignot specifically
  • ripening agents other than bromide ion e.g., bromide ion
  • beneficial effects can be achieved when silver halide emulsion layers are used in color photographic elements comprising compounds that contain photographically useful groups that are released upon reaction with oxidized developing agent. Such compounds are used to achieve such desired effects as an interlayer or interimage effect or an image accutance effect.
  • These compounds can be simply referred to as "photographically useful group-releasing compounds", as more fully described hereinafter, and are illustrated in U.S. Patent Nos. 4,248,962; 4,409,323 and 4,861,701 and European Patent Application 354,532.
  • An example of such photographically useful group-releasing compounds are the Development Inhibitor Releasing (DIR) compounds which are known in the photographic art. DIR compounds can release development inhibitors during photographic processing and such inhibitors can be used to provide a variety of photographic effects such as decreasing gamma which can be used to control curve shape.
  • DIR Development Inhibitor Releasing
  • Maskasky U.S. Serial No.____________ filed concurrently herewith as a continuation-in-part of U.S. Serial No. 955,010, filed Oct. 1, 1992, which is in turn a continuation-in-part of U.S. Serial No. 764,868, filed Sept. 24, 1991, titled HIGH TABULARITY HIGH CHLORIDE EMULSIONS WITH INHERENTLY STABLE GRAIN FACES, commonly assigned, hereinafter referred to as Maskasky III, discloses high aspect ratio tabular grain high chloride emulsions containing tabular grains that are internally free of iodide and that have ⁇ 100 ⁇ major faces. In a preferred form, Maskasky III employs an organic compound containing a nitrogen atom with a resonance stabilized p electron pair to favor formation of ⁇ 100 ⁇ faces.
  • each commonly assigned, titled PROCESSES OF PREPARING TABULAR GRAIN EMULSIONS discloses processes of preparing emulsions containing tabular grains bounded by ⁇ 100 ⁇ major faces of which tabular grains bounded by ⁇ 100 ⁇ major faces account for 50 percent of total grain projected area selected on the criteria of adjacent major face edge ratios of less than 10 and thicknesses of less than 0.3 mm and internally at their nucleation site contain iodide and at least 50 mole percent chloride, comprised of the steps of (1) introducing silver and halide salts into the dispersing medium so that
  • nucleation of the tabular grains occurs in the presence of iodide with chloride accounting for at least 50 mole percent of the halide present in the dispersing medium and the pCl of the dispersing medium being maintained in the range of from 0.5 to 3.5 and (2) following nucleation completing grain growth under conditions that maintain the ⁇ 100 ⁇ major faces of the tabular grains until the tabular grains exhibit an average aspect ratio of greater than 8.
  • OLIGOMER MODIFIED TABULAR GRAIN EMULSIONS discloses radiation sensitive emulsions and processes for their preparation. At least 50 percent of total grain
  • high chloride tabular grains bounded by ⁇ 100 ⁇ major faces having adjacent edge ratios of less than 10, each having an aspect ratio of at least 2 and containing on average at least one pair of metal ions chosen from group VIII, periods 5 and 6, at adjacent cation sites in their crystal lattice.
  • COORDINATION COMPLEX LIGAND MODIFIED TABULAR GRAIN EMULSIONS discloses emulsions containing tabular grains bounded by ⁇ 100 ⁇ major faces accounting for 50 percent of total grain projected area selected on the criteria of adjacent major face edge ratios of less than 10 and thicknesses of less than 0.3 m and having higher aspect ratios than any remaining tabular grains satisfying these criteria (1) have an average aspect ratio of greater than 8 and (2) internally at their nucleation site contain iodide and at least 50 mole percent chloride.
  • the tabular grain contain non-halide coordination complex ligands.
  • EMULSIONS discloses digitally imaging photographic elements containing tabular grain emulsions comprised of a dispersing medium and silver halide grains containing at least 50 mole percent chloride based, on silver. At least 50 percent of total grain projected area is
  • dispersing medium and silver halide grains containing at least 50 mole percent chloride based on silver. At least 50 percent of total grain projected area is accounted for by tabular grains bounded by ⁇ 100 ⁇ major faces having adjacent edge ratios of less than 10, each having an aspect ratio of at least 2.
  • tabular grain emulsions comprised of a dispersing medium, silver halide grains containing at least 50 mole percent chloride based on silver and at least one selected antifoggant or stabilizer. At least 50 percent of total grain projected area is accounted for by tabular grains bounded by ⁇ 100 ⁇ major faces having adjacent edge ratios of less than 10, each having an aspect ratio of at least 2.
  • MODERATE ASPECT RATIO TABULAR GRAIN HIGH CHLORIDE EMULSIONS WITH INHERENTLY STABLE GRAIN FACES discloses an emulsion containing a grain population internally free of iodide at the grain nucleation site and comprised of at least 50 mole percent chloride. At least 50 percent of the grain population projected area is accounted for by ⁇ 100 ⁇ tabular grains each having an aspect ratio of at least 2 and together having an average aspect ratio of up to 7.5.
  • ELEMENTS CONTAINING TABULAR GRAIN EMULSIONS discloses a process of developing and desilvering a dye image forming photographic element containing a high chloride ⁇ 100 ⁇ tabular grain emulsions of the type herein disclosed.
  • this invention is directed to a color photographic element having a support bearing at least one radiation sensitive emulsion layer comprising dispersing medium and silver halide grains, and having in reactive association an image dye-forming compound. At least 50 percent of the total grain projected area is accounted for by tabular grains that are bounded by 100 major faces having adjacent edge ratios of less than 10 and each having an aspect ratio of at least 2.
  • the emulsion layer is also in reactive association with a compound that contains a photographically useful group and is capable of reacting with oxidized developing agent to thereby release such group.
  • color photographic elements can be developed in conventional color processing techniques to obtain processed elements exhibiting exceptional image
  • color photographic elements of this invention which comprise photographically useful groups such as development inhibitor groups that are released upon reaction with oxidized developing agent, provide
  • this invention provides excellent flexibility in choosing a desired specific photographic activity since a wide variety of compounds which release
  • suitable photographically useful groups include development inhibitors, development accelerators, bleach inhibitors, bleach accelerators, electron transfer agents or couplers such as competing couplers.
  • the present invention has been facilitated by the discovery of a novel approach to forming tabular grains. Instead of introducing parallel twin planes in grains as they are being formed to induce tabularity and thereby produce tabular grains with ⁇ 111 ⁇ major faces, it has been discovered that the presence of iodide in the dispersing medium during a high chloride nucleation step coupled with maintaining the chloride ion in solution within a selected pCl range results in the formation of a tabular grain emulsion in which the tabular grains are bounded by ⁇ 100 ⁇ crystal faces.
  • the invention extends to silver chloride and silver
  • bromochloride emulsions each of which can be prepared by variant precipitation procedures that do not require the presence of iodide ion during grain nucleation.
  • Figure 1 is a shadowed photomicrograph of carbon grain replicas of a representative emulsion prepared according to Illustrative Emulsion Preparation, Preparation I, which is a typical emulsion useful in the color photographic elements of this invention.
  • Figure 2 is a shadowed photomicrograph of carbon grain replicas of a control emulsion prepared according to Illustrative Emulsion Preparation,
  • Figure 1 is a shadowed photomicrograph of carbon grain replicas of a
  • rods acicular or rod-like grains
  • These grains are more than 10 times longer in one dimension than in any other dimension and can be excluded from the desired tabular grain population based on their high ratio of edge lengths.
  • the projected area accounted for by the rods is low, but, when rods are present, their projected area is noted for determining total grain projected area.
  • ECD is determined by measuring the projected area (the product of edge lengths) of the upper surface of each grain. From the grain projected area the ECD of the grain is calculated.
  • Grain thickness is commonly determined by oblique illumination of the grain population resulting in the individual grains casting shadows. From a knowledge of the angle of illumination (the shadow angle) it is possible to calculate the thickness of a grain from a measurement of its shadow length.
  • the grains having square or rectangular faces and each having a ratio of ECD/t of at least 2 are tabular grains having ⁇ 100 ⁇ major faces. When the projected areas of the ⁇ 100 ⁇ tabular grains account for at least 50 percent of total grain projected area, the emulsion is a tabular grain emulsion.
  • tabular grains account for more than 50 percent of total grain projected area. From the definition of a tabular grain above, it is apparent that the average aspect ratio of the tabular grains can only approach 2 a minimum limit. In fact, tabular grain emulsions of the invention typically exhibit average aspect ratios of 5 or more, with high average aspect ratios (>8) being preferred. That is, preferred emulsions according to the invention are high aspect ratio tabular grain emulsions. In specifically preferred emulsions according to the invention average aspect ratios of the tabular grain population are at least 12 and optimally at least 20. Typically the average aspect ratio of the tabular grain population ranges up to 50, but higher aspect ratios of 100, 200 or more can be realized.
  • Emulsions within the contemplation of the invention in which the average aspect ratio approaches the minimum average aspect ratio limit of 2 still provide a surface to volume ratio that is 200 percent that of cubic grains.
  • the tabular grain population can exhibit any grain thickness that is compatible with the average aspect ratios noted above. However, particularly when the selected tabular grain population exhibits a high average aspect ratio, it is preferred to additionally limit the grains included in the selected tabular grain population to those that exhibit a thickness of less than 0.3 mm and, optimally, less than 0.2 mm. It is appreciated that the aspect ratio of a tabular grain can be limited either by
  • the tabular grains accounting for at least 50 percent of total grain projected area can also eaach exhibit a grain thickness of less than 0.3 mm or less than 0.2 mm. Nevertheless, in the aspect ratio range of from 2 to 8 particularly, there are specific photographic elements
  • major face edge length ratios exhibits major face edge length ratios of less than 5 and optimally less than 2.
  • the tabular grain population accounting for at least 50 percent of total grain projected area is
  • the emulsions are in this instance thin tabular grain emulsions.
  • ultrathin tabular grain emulsions have been prepared satisfying the requirements of the invention.
  • Ultrathin tabular grain emulsions are those in which the selected tabular grain population is made up of tabular grains having an average thickness of less than 0.06 mm.
  • the only ultrathin tabular grain emulsions of a halide content exhibiting a cubic crystal lattice structure known in the art contained tabular grains bounded by ⁇ 111 ⁇ major faces. In other words, it was thought essential to form tabular grains by the mechanism of parallel twin plane incorporation to achieve ultrathin dimensions.
  • Emulsions according to the invention can be prepared in which the tabular grain population has a mean thickness down to 0.02 mm and even 0.01 mm.
  • Ultrathin tabular grains have extremely high surface to volume ratios. This permits ultrathin grains to be photographically processed at accelerated rates. Further, when spectrally sensitized, ultrathin tabular grains exhibit very high ratios of speed in the spectral region of sensitization as compared to the spectral region of native sensitivity. For example, ultrathin tabular grain emulsions according to the invention can have entirely negligible levels of blue sensitivity, and are therefore capable of providing a green or red record in a photographic product that exhibits minimal blue contamination even when located to receive blue light.
  • T is tabularity
  • AR is aspect ratio
  • ECD is equivalent circular diameter in micrometers
  • t is grain thickness in micrometers.
  • the high chloride tabular grain population accounting for 50 percent of total grain projected area preferably exhibits a tabularity of greater than 25 and most preferably greater than 100. Since the tabular grain population can be ultrathin, it is apparent that
  • the tabular grain population can exhibit an average ECD of any photographically useful magnitude.
  • ECD's of less than 10 mm are contemplated, although average ECD's in most
  • the preferred emulsions according to the invention are those in which at least 70 percent and optimally at least 90 percent of total grain projected area is accounted for by tabular grains having ⁇ 100 ⁇ major faces. It is specifically contemplated to provide emulsions satisfying the grain descriptions above in which the selection of the rank ordered tabular grains extends to sufficient tabular grains to account for 70 percent or even 90 percent of total grain projected area.
  • emulsions are photographically inferior in which many or all of the tabular grains are relatively thick—e.g., emulsions containing high proportions of tabular grains with thicknesses in excess of 0.3 mm.
  • the tabular grain emulsion of Figure 1 satisfying the requirements of the invention and the predominantly cubic grain emulsion of Figure 2 were prepared under conditions that were identical, except for iodide management during nucleation.
  • the Figure 2 emulsion is a silver chloride emulsion while the emulsion of Figure 1 additionally includes a small amount of iodide.
  • emulsions satisfying the requirements of the invention has been achieved by the discovery of a novel precipitation process.
  • grain nucleation occurs in a high chloride environment in the presence of iodide ion under conditions that favor the emergence of ⁇ 100 ⁇ crystal faces.
  • iodide ion the inclusion of iodide into the cubic crystal lattice being formed by silver ions and the remaining halide ions is disruptive because of the much larger diameter of iodide ion as compared to chloride ion.
  • the incorporated iodide ions introduce crystal irregularities that in the course of further grain growth result in tabular grains rather than regular (cubic) grains.
  • cubic grain nuclei being formed having one or more screw dislocations in one or more of the cubic crystal faces.
  • the cubic crystal faces that contain at least one screw dislocation thereafter accept silver halide at an accelerated rate as compared to the regular cubic crystal faces (i.e., those lacking a screw dislocation).
  • the regular cubic crystal faces i.e., those lacking a screw dislocation.
  • reaction vessel containing a dispersing medium and conventional silver and reference electrodes for
  • dispersing medium halide ion is introduced into the dispersing medium that is at least 50 mole percent chloride--i.e., at least half by number of the halide ions in the dispersing medium are chloride ions.
  • the pCl of the dispersing medium is adjusted to favor the formation of ⁇ 100 ⁇ grain faces on nucleation—that is, within the range of from 0.5 to 3.5, preferably within the range of from 1.0 to 3.0 and, optimally, within the range of from 1.5 to 2.5.
  • the grain nucleation step is initiated when a silver jet is opened to introduce silver ion into the dispersing medium.
  • Iodide ion is preferably introduced into the dispersing medium concurrently with or,
  • silver iodochloride grain nuclei are formed during the
  • nucleation step Minor amounts of bromide ion can be present in the dispersing medium during nucleation. Any amount of bromide ion can be present in the dispersing medium during nucleation that is compatible with at least 50 mole percent of the halide in the grain nuclei being chloride ions.
  • the grain nuclei preferably contain at least 70 mole percent and optimally at least 90 mole percent chloride ion, based on silver.
  • Grain nuclei formation occurs instantaneously upon introducing silver ion into the dispersing medium.
  • silver ion introduction during the nucleation step is preferably extended for a convenient period, typically from 5 seconds to less than a minute. So long as the pCl remains within the ranges set forth above no additional chloride ion need be added to the dispersing medium during the nucleation step. It is, however, preferred to introduce both silver and halide salts concurrently during the nucleation step.
  • the advantage of adding halide salts concurrently with silver salt throughout the nucleation step is that this permits assurance that any grain nuclei formed after the outset of silver ion addition are of essentially similar halide content as those grain nuclei initially formed.
  • Iodide ion addition during the nucleation step is particularly preferred. Since the deposition rate of iodide ion far exceeds that of the other halides, iodide will be depleted from the dispersing medium unless replenished.
  • Silver ion is preferably introduced as an aqueous silver salt solution, such as a silver nitrate solution.
  • Halide ion is preferably introduced as alkali or alkaline earth halide, such as lithium, sodium and/or potassium chloride, bromide and/or iodide.
  • the dispersing medium contained in the reaction vessel prior to the nucleation step is comprised of water, the dissolved halide ions discussed above and a peptizer.
  • the dispersing medium can exhibit a pH within any convenient conventional range for silver halide precipitation, typically from 2 to 8. It is preferred, but not required, to maintain the pH of the dispersing medium on the acid side of neutrality (i.e., ⁇ 7.0). To minimize fog a preferred pH range for precipitation is from 2.0 to 5.0.
  • Mineral acids such as nitric acid or hydrochloride acid, and bases, such as alkali hydroxides, can be used to adjust the pH of the dispersing medium. It is also possible to incorporate pH buffers.
  • the peptizer can take any convenient conventional form known to be useful in the precipitation of photographic silver halide emulsions and particularly tabular grain silver halide emulsions.
  • a summary of conventional peptizers is provided in Research
  • gelatino peptizers e.g., gelatin and gelatin derivatives.
  • gelatino peptizers As manufactured and employed in photography gelatino peptizers typically contain
  • divalent or trivalent metal ions such alkaline earth or earth metal ions, preferably magnesium, calcium, barium or aluminum ions.
  • peptizers are low methionine gelatino peptizers (i.e., those containing less than 30 micromoles of methionine per gram of peptizer), optimally less than 12 micromoles of methionine per gram of peptizer, these peptizers and their preparation are described by Maskasky II and King et al, cited above, the disclosures of which are here incorporated by reference.
  • the grain growth modifiers of the type taught for inclusion in the emulsions of Maskasky I and II are not appropriate for inclusion in the dispersing media of this invention, since these grain growth modifiers promote twinning and the formation of tabular grains having ⁇ 111 ⁇ major faces.
  • adenine e.g., adenine
  • the grain growth modifiers promote twinning and the formation of tabular grains having ⁇ 111 ⁇ major faces.
  • at least about 10 percent and typically from 20 to 80 percent of the dispersing medium forming the completed emulsion is present in the reaction vessel at the outset of the nucleation step. It is conventional practice to maintain relatively low levels of peptizer, typically from 10 to 20 percent of the peptizer present in the completed emulsion, in the reaction vessel at the start of precipitation.
  • peptizer typically from 10 to 20 percent of the peptizer present in the completed emulsion, in the reaction vessel at the start of precipitation.
  • the concentration of the peptizer in the dispersing medium be in the range of from 0.5 to 6 percent by weight of the total weight of the dispersing medium at the outset of the nucleation step. It is conventional practice to add gelatin, gelatin derivatives and other vehicles and vehicle extenders to prepare emulsions for coating after precipitation. Any naturally occurring level of methionine can be present in gelatin and gelatin derivatives added after precipitation is complete.
  • the nucleation step can be performed at any convenient conventional temperature for the precipitation of silver halide emulsions. Temperatures ranging from near ambient—e.g., 30°C up to about 90°C are examples of near ambient—e.g., 30°C up to about 90°C.
  • nucleation temperatures in the range of from 35 to 70°C being preferred.
  • a grain growth step follows the nucleation step in which the grain nuclei are grown until tabular grains having ⁇ 100 ⁇ major faces of a desired average ECD are obtained. Whereas the objective of the nucleation step is to form a grain population having the desired
  • the objective of the growth step is to deposit additional silver halide onto (grow) the existing grain population while avoiding or minimizing the formation of additional grains. If additional grains are formed during the growth step, the polydispersity of the emulsion is increased and, unless conditions in the reaction vessel are maintained as described above for the nucleation step, the additional grain population formed in the growth step will not have the desired tabular grain properties described above.
  • the process of preparing emulsions according to the invention can be performed as a single jet precipitation without interrupting silver ion introduction from start to finish.
  • emulsions In the preparation of emulsions according to the invention it is preferred to interrupt silver and halide salt introductions at the conclusion of the nucleation step and before proceeding to the growth step that brings the emulsions to their desired final size and shape.
  • the emulsions are held within the temperature ranges described above for nucleation for a period sufficient to allow reduction in grain dispersity.
  • a holding period can range from a minute to several hours, with typical holding periods ranging from 5 minutes to an hour.
  • relatively smaller grain nuclei are Ostwald ripened onto surviving, relatively larger grain nuclei, and the overall result is a
  • the rate of ripening can be any rate of ripening.
  • a conventional simple approach to accelerating ripening is to increase the halide ion concentration in the dispersing medium. This creates complexes of silver ions with plural halide ions that accelerate ripening. When this approach is employed, it is preferred to increase the chloride ion concentration in the dispersing medium. That is, it is preferred to lower the pCl of the dispersing medium into a range in which increased silver chloride solubility is observed.
  • ripening can be accelerated and the percentage of total grain projected area accounted for by ⁇ 100 ⁇ tabular grains can be increased by employing conventional ripening agents.
  • Preferred ripening agents are sulfur containing ripening agents, such as thioethers and thiocyanates.
  • Typical thiocyanate ripening agents are disclosed by Nietz et al U.S. Patent 2,222,264, Lowe et al U.S. Patent 2,448,534 and Illingsworth U.S. Patent 3,320,069, the disclosures of which are here incorporated by reference.
  • Typical thioether ripening agents are disclosed by McBride U.S. Patent 3,271,157, Jones U.S. Patent 3,574,628 and Rosencrantz et al U.S. Patent
  • any halide or combination of halides known to form a cubic crystal lattice structure can be employed during the growth step.
  • iodide nor chloride ions need be incorporated in the grains during the growth step, since the irregular grain nuclei faces that result in tabular grain growth, once introduced, persist during subsequent grain growth independently of the halide being precipitated, provided the halide or halide combination is one that forms a cubic crystal lattice. This excludes only iodide levels above 13 mole percent (preferably 6 mole percent) in precipitating silver iodochloride, levels of iodide above 40 mole percent (preferably 30 mole percent) in
  • iodobromochlqride is being deposited during the growth step, it is preferred to maintain the pCl within the dispersing medium within the ranges noted above in describing the nucleation step.
  • both silver and halide salts are preferably introduced into the dispersing medium.
  • double jet precipitation is contemplated, with added iodide salt, if any, being introduced with the remaining halide salt or through an independent jet.
  • the rate at which silver and halide salts are introduced is controlled to avoid
  • Addition rate control to avoid renucleation is generally well known in the art, as illustrated by Wilgus German OLS No. 2,107,118, Irie U.S. Patent
  • nucleation and growth stages of grain precipitation occur in the same reaction vessel. It is, however, recognized that grain precipitation can be interrupted, particularly after completion of the nucleation stage. Further, two separate reaction vessels can be substituted for the single reaction vessel described above.
  • the nucleation stage of grain preparation can be performed in an
  • nucleation reaction vessel upstream reaction vessel
  • growth reaction vessel downstream reaction vessel in which the growth stage of grain precipitation occurs
  • an enclosed nucleation vessel can be employed to receive and mix reactants upstream of the growth reaction vessel, as illustrated by Posse et al U.S.
  • Mignot U.S. Patent 4,334,012 which also discloses the useful feature of ultrafiltration during grain growth
  • Urabe U.S. Patent 4,879,208 and published European Patent Applications 326,852, 326,853, 355,535 and 370,116 Ichizo published European Patent Application 0 368 275
  • nucleation can be achieved essentially instantaneously, immediate departures from initial supersaturation to the preferred pCl ranges noted above are entirely consistent with this approach.
  • Mignot U.S. Patent 4,334,012 illustrates grain nucleation in the absence of a peptizer with removal of soluble salt reaction products to avoid coalescence of nuclei. Since limited coalescence of grain nuclei is considered desirable, the active
  • coalescence can be either eliminated or moderated. It is also contemplated to enhance limited grain coalescence by employing one or more peptizers that exhibit reduced adhesion to grain surfaces. For example, it is generally recognized that low methionine gelatin of the type disclosed by Maskasky II is less tightly absorbed to grain surfaces than gelatin containing higher levels of methionine. Further moderated levels of grain adsorption can be achieved with so-called “synthetic peptizers”—that is, peptizers formed from synthetic polymers. The maximum quantity of peptizer compatible with limited coalescence of grain nuclei is, of course, related to the strength of adsorption to the grain surfaces. Once grain nucleation has been completed, immediately after silver salt introduction, peptizer levels can be increased to any convenient conventional level for the remainder of the precipitation process.
  • the emulsions of the invention include silver chloride, silver iodochloride emulsions, silver iodo- bromochloride emulsions and silver iodochlorobromide emulsions. Dopants, in concentrations of up to 10 -2 mole per silver mole and typically less than 10 -4 mole per silver mole, can be present in the grains.
  • Compounds of metals such as copper, thallium, lead, mercury, bismuth, zinc, cadmium , rhenium, and Group VIII metals (e.g., iron, ruthenium, rhodium, palladium, osmium, iridium, and platinum) can be present during grain precipitation, preferably during the growth stage of precipitation.
  • metals such as copper, thallium, lead, mercury, bismuth, zinc, cadmium , rhenium, and Group VIII metals (e.g., iron, ruthenium, rhodium, palladium, osmium, iridium, and platinum) can be present during grain precipitation, preferably during the growth stage of precipitation.
  • the modification of photographic properties is related to the level and location of the dopant within the grains .
  • the metal forms a part of a coordination complex, such as a hexacoordination complex or a tetracoordination complex
  • the ligands can also be included within the grains and the ligands can further influence photographic properties.
  • Coordination ligands such as halo, aquo, cyano cyanate, thiocyanate, nitrosyl, thionitrosyl, oxo and carbonyl ligands are contemplated and can be relied upon to modify photographic properties.
  • the invention is particularly advantageous in providing high chloride (greater than 50 mole percent chloride) tabular grain emulsions, since conventional high chloride tabular grain emulsions having tabular grains bounded by ⁇ 111 ⁇ are inherently unstable and require the presence of a morphological stabilizer to prevent the grains from regressing to nontabular forms.
  • Particularly preferred high chloride emulsions are according to the invention that are those that contain more than 70 mole percent (optimally more than 90 mole percent) chloride-.
  • the restraining agent when employed, can be active during grain nucleation, during grain growth or throughout precipitation.
  • contemplated conditions of precipitation are organic compounds containing a nitrogen atom with a resonance stabilized p electron pair. Resonance stabilization prevents protonation of the nitrogen atom under the relatively acid conditions of precipitation.
  • Aromatic resonance can be relied upon for stabilization of the p electron pair of the nitrogen atom.
  • the nitrogen atom can either be incorporated in an aromatic ring, such as an azole or azine ring, or the nitrogen atom can be a ring substituent of an aromatic ring.
  • the restraining agent can satisfy the following formula:
  • structures include 2H-pyrrole, pyrrole, imidazole, pyrazole, 1,2,3-triazole, 1,2,4-triazole, 1,3,5-triazole, pyridine, pyrazine, pyrimidine, and pyridazine.
  • Ar is an aromatic ring structure containing from 5 to 14 carbon atoms and
  • R 1 and R 2 are independently hydrogen, Ar, or any convenient aliphatic group or together complete a five or six membered ring.
  • Ar is preferably a carbocyclic aromatic ring, such as phenyl or naphthyl.
  • any of the nitrogen and carbon containing aromatic rings noted above can be attached to the nitrogen atom of formula II through a ring carbon atom.
  • the resulting compound satisfies both formulae I and II. Any of a wide variety of aliphatic groups can be selected.
  • aliphatic groups are alkyl groups, preferably those containing from 1 to 10 carbon atoms and most preferably from 1 to 6 carbon atoms. Any functional substituent of the alkyl group known to be compatible with silver halide precipitation can be present. It is also contemplated to employ cyclic aliphatic substituents exhibiting 5 or 6 membered rings, such as cycloalkane, cycloalkene and aliphatic heterocyclic rings, such as those containing oxygen and/or nitrogen hetero atoms. Cyclopentyl, cyclohexyl, pyrrolidinyl, piperidinyl, furanyl and similar heterocyclic rings are specifically contemplated.
  • Selection of preferred restraining agents and their useful concentrations can be accomplished by the following selection procedure:
  • the compound being considered for use as a restraining agent is added to a silver chloride emulsion consisting essentially of cubic grains with a mean grain edge length of 0.3 m.
  • the emulsion is 0.2 M in sodium acetate, has a pCl of 2.1, and has a pH that is at least one unit greater than the pKa of the compound being considered.
  • the emulsion is held at 75°C with the restraining agent present for 24 hours.
  • the compound introduced is performing the function of a restraining agent. The significance of sharper edges of intersection of the
  • ⁇ 100 ⁇ crystal faces lies in the fact that grain edges are the most active sites on the grains in terms of ions reentering the dispersing medium. By maintaining sharp edges the restraining agent is acting to restrain the emergence of non- ⁇ 100 ⁇ crystal faces, such as are present, for example, at rounded edges and corners. In some instances instead of dissolved silver chloride depositing exclusively onto the edges of the cubic grains a new population of grains bounded by ⁇ 100 ⁇ crystal faces is formed. Optimum restraining agent activity occurs when the new grain.population is a tabular grain
  • the emulsions used in this invention can be chemically sensitized with active gelatin as illustrated by T. H. James, The Theory of the Photographic Process, 4th Ed., Macmillan, 1977, pp. 67-76, or with sulfur, selenium, tellurium, gold, platinum, palladium, iridium, osmium, rhenium or phosphorus sensitizers or combinations of these sensitizers, such as at pAg levels of from 5 to 10, pH levels of from 5 to 8 and temperatures of from 30 to 80°C, as illustrated by Research Disclosure, Vol. 120, April, 1974, Item 12008, Research Disclosure, Vol. 134, June, 1975, Item 13452, Sheppard et al U.S. Patent
  • Patent 2,642,361 McVeigh U.S. Patent 3,297,447, Dunn U.S. Patent 3,297,446, McBride U.K. Patent 1,315,755, Berry et al U.S. Patent 3,772,031, Gilman et al U.S.
  • the emulsions can be reduction- sensitized—e.g., with hydrogen, as illustrated by
  • Janusonis U.S. Patent 3,891,446 and Babcock et al U.S. Patent 3,984,249 by low pAg (e.g., less than 5), high pH (e.g., greater than 8) treatment, or through the use of reducing agents such as stannous chloride, thiourea dioxide, polyamines and amineboranes as illustrated by Allen et al U.S. Patent 2,983,609, Oftedahl et al
  • Chemical sensitization can be directed to specific sites or crystallographic faces on the silver halide grain as described by Haugh et al U.K. Patent Application
  • resulting from chemical sensitization can be partially o totally occluded by the precipitation of additional layers of silver halide using such means as twin-jet additions or pAg cycling with alternate additions of silver and halide salts as described by Morgan U.S.
  • Patent 3,917,485 Becker U.S. Patent 3,966,476 and
  • the chemical sensitizers can be added prior to or concurrently with the additional silver halide formation. Chemical sensitization can take place during or after halide conversion as described by Hasebe et al European Patent Application EP 273,404. In many instances epitaxial deposition onto selected tabular grain sites (e.g., edge or corners) can either be used to direct chemical sensitization or to itself perform the functions normall performed by chemical sensitization.
  • the emulsions can be spectrally sensitized wit dyes from a variety of classes, including the polymethin dye class, which includes the cyanines, merocyanines, complex cyanines and merocyanines (i.e., tri-, tetra- an polynuclear cyanines and merocyanines), styryls, merostyryls, streptocyanines, hemicyanines, arylidenes, allopolar cyanines and enamine cyanines.
  • the cyanine spectral sensitizing dyes include, joined by a methine linkage, two basic heterocyclic nuclei, such as those derived from quinolinium,
  • pyridinium isoquinolinium, 3H-indolium, benzindolium, oxazolium, thiazolium, selenazolinium, imidazolium, benzoxazolium, benzothiazolium, benzoselenazolium, benzotellurazolium, benzimidazolium, naphthoxazolium, naphthothiazolium, naphthoselenazolium,
  • the merocyanine spectral sensitizing dyes include, joined by a methine linkage, a basic
  • heterocyclic nucleus of the cyanine-dye type and an acidic nucleus such as can be derived from barbituric acid, 2-thiobarbituric acid, rhodanine, hydantoin,
  • 2-thiohydantoin 4-thiohydantoin, 2-pyrazolin-5-one, 2-isoxazolin-5-one, indan-1,3-dione, cyclohexan-1,3- dione, 1,3-dioxane-4,6-dione, pyrazolin-3,5-dione, pentan-2,4-dione, alkylsulfonyl acetonitrile,
  • One or more spectral sensitizing dyes may be employed. Dyes with sensitizing maxima at wavelengths throughout the visible and infrared spectrum and with a great variety of spectral sensitivity curve shapes are known. The choice and relative proportions of dyes depends upon the region of the spectrum to which
  • Combinations of spectral sensitizing dyes can be used which result in supersensitization—that is, spectral sensitization greater in some spectral region than that from any concentration of one of the dyes alone or that which would result from the additive effect of the dyes .
  • Supersensitization can be achieved with selected combinations of spectral sensitizing dyes and other addenda such as stabilizers and antifoggants, development accelerators or inhibitors, coating aids, brighteners and antistatic agents. Any one of several mechanisms, as well as compounds which can be responsible for supersensitization, are discussed by Gilman,
  • Spectral sensitizing dyes can also affect the emulsions in other ways. For example, spectrally
  • sensitizing dyes can increase photographic speed within the spectral region of inherent sensitivity.
  • Spectral sensitizing dyes can also function as antifoggants or stabilizers, development accelerators or inhibitors, reducing or nucleating agents, and halogen acceptors or electron acceptors, as disclosed in Brooker et al U.S. Patent 2,131,038, Illingsworth et al U.S. Patent
  • Spectral sensitizing dyes can be added at any stage during the emulsion preparation. They may be added at the beginning of or during precipitation as described by Wall, Photographic Emulsions, American Photographic Publishing Co., Boston, 1929, p. 65, Hill U.S. Patent 2,735,766, Philippaerts et al U.S. Patent 3,628,960, Locker U.S. Patent 4,183,756, Locker et al U.S. Patent 4,225,666 and Research Disclosure, Vol. 181, May, 1979, Item 18155, and Tani et al published European Patent Application EP 301,508. They can be added prior to or during chemical sensitization as described by Kofron et al U.S. Patent 4,439,520, Dickerson U.S. Patent
  • Postprocessing dye stain can be reduced by the proximity to the dyed emulsion layer of fine high-iodide grains as described by Dickerson.
  • the spectral-sensitizing dyes can be added to the emulsion as solutions in water or such solvents as methanol, ethanol, acetone or pyridine; dissolved in surfactant solutions as described by Sakai et al U.S. Patent 3,822,135; or as dispersions as described by Owens et al U.S. Patent 3,469,987 and Japanese published Patent Application (Kokai) 24185/71.
  • the dyes can be selectively adsorbed to particular crystallographic faces of the emulsion grain as a means of restricting chemical sensitization centers to other faces, as described by Mifune et al published European Patent Application 302,528.
  • the spectral sensitizing dyes may be used in conjunction with poorly adsorbed luminescent dyes, as described by Miyasaka et al
  • antifoggants effective in the emulsions used in this invention can also be used in developers and can be classified under a few general headings, as illustrated by C.E.K. Mees, The Theory of the Photographic Process, 2Nd Ed., Macmillan, 1954, pp. 677-680.
  • stabilizers and antifoggants can be employed, such as halide ions (e.g., bromide salts); chloropalladates and chloropalladites as illustrated by Trivelli et al U.S. Patent 2,566,263; water-soluble inorganic salts of magnesium, calcium, cadmium, cobalt, manganese and zinc as illustrated by Jones U.S. Patent 2,839,405 and
  • High-chloride emulsions can be stabilized by the presence, especially during chemical sensitization, of elemental sulfur as described by Miyoshi et al
  • benzothiazole benzoxazole, naphthothiazole and certain merocyanine .and cyanine dyes, as illustrated by Yutzy et al U.S. Patent 2,597,915, and sulfinamides, as
  • tetraazaindenes particularly in combination with Group VIII noble metals or resorcinol derivatives, as illustrated by Carroll et al U.S. Patent 2,716,062, U.K. Patent 1,466,024 and Habu et al U.S.
  • Patent 3,929,486 quaternary ammonium salts of the type illustrated by Piper U.S. Patent 2,886,437; water- insoluble hydroxides as illustrated by Maffet U.S. Patent 2,953,455; phenols as illustrated by Smith U.S. Patents 2,955,037 and '038; ethylene diurea as illustrated by Dersch U.S. Patent 3,582,346; barbituric acid derivatives as illustrated by Wood U.S. Patent 3,617,290; boranes as illustrated by Bigelow U.S. Patent 3,725,078; 3- pyrazolidinones as illustrated by Wood U.K. Patent
  • the emulsions can be protected from fog and desensitization caused by trace amounts of metals such as copper, lead, tin, iron and the like by incorporating addenda such as sulfocatechol-type compounds, as
  • aldoximines as illustrated by Carroll et al U.K. Patent 623,448 and meta- and polyphosphates as illustrated by Draisbach U.S. Patent 2,239,284, and carboxylic acids such as ethylenediamine tetraacetic acid as illustrated by U.K. Patent 691,715.
  • stabilizers useful in layers containing synthetic polymers of the type employed as vehicles and to improve covering power are monohydric and polyhydric phenols as illustrated by Forsgard U.S. Patent 3,043,697; saccharides as illustrated by U.K. Patent 897,497 and Stevens et al U.K. Patent 1,039,471, and quinoline derivatives as illustrated by Dersch et al U.S. Patent 3,446,618.
  • stabilizers useful in protecting the emulsion layers against dichroic fog are addenda such as salts of nitron as illustrated by Barbier et al U.S.
  • stabilizers useful in protecting emulsion layers against development fog are addenda such as azabenzimidazoles as illustrated by Bloom et al U.K.
  • Patent 3,706,557 isothiourea derivatives as illustrated by Herz et al U.S. Patent 3,220,839, and thiodiazole derivatives as illustrated by von Konig U.S. Patent
  • the emulsion layers can be protected with antifoggants such as monohydric and polyhydric phenols of the type illustrated by Sheppard et al U.S. Patent
  • addenda can be employed such as parabanic acid, hydantoin acid hydrazides and urazoles as illustrated by Anderson et al U.S. Patent 3,287,135, and piazines containing two symmetrically fused 6-member carbocyclic rings, especially in combination with an aldehyde-type hardening agent, as illustrated in Rees et al U.S. Patent 3,396,023.
  • Kink desensitization of the emulsions can be reduced by the incorporation of thallous nitrate as illustrated by Overman U.S. Patent 2,628,167; compounds, polymeric latices and dispersions of the type disclosed by Jones et al U.S. Patents 2,759,821 and '822; azole and mercaptotetrazole hydrophilic colloid dispersions of the type disclosed by Research Disclosure, Vol. 116,
  • color photographic element of this invention is to be processed at elevated bath or drying temperatures pressure desensitization and/or increased fog can be controlled by selected combinations of
  • latent-image stabilizers can be incorporated, such as amino acids, as illustrated by Ezekiel U.K. Patents 1,335,923, 1,378,354, 1,387,654 and 1,391,672, Ezekiel et al U.K. Patents 1,335,923, 1,378,354, 1,387,654 and 1,391,672, Ezekiel et al U.K. Patents 1,335,923, 1,378,354, 1,387,654 and 1,391,672, Ezekiel et al U.K. Patents 1,335,923, 1,378,354, 1,387,654 and 1,391,672, Ezekiel et al U.K. Patent
  • photographic elements of this invention can take any convenient conventional form. Substitution in color photographic elements for conventional emulsions of the same or similar silver halide composition is generally contemplated, with substitution for silver halide
  • a dye image-forming compound is typically a coupler compound, a dye redox releaser compound, a dye developer compound, an oxichromic developer compound, or a bleachable dye or dye precursor compound.
  • Dye redox releaser, dye developer, and oxichromic developer are typically a coupler compound, a dye redox releaser compound, a dye developer compound, an oxichromic developer compound, or a bleachable dye or dye precursor compound.
  • Preferred dye image-forming compounds are coupler compounds, which react with oxidized color developing agents to form colored products, or dyes.
  • a coupler compound contains a coupler moiety COUP, which is combined with the oxidized developer species in the coupling reaction to form the dye structure.
  • a coupler compound can additionally contain a group, called a coupling-off group, that is attached to the coupler moiety by a bond that is cleaved upon reaction of the coupler compound with oxidized color developing agent.
  • Coupling-off groups can be halogen, such as chloro, bromo, fluoro, and iodo, or organic radicals that are attached to the coupler moieties by atoms such as oxygen, sulfur, nitrogen, phosphorus, and the like.
  • a PUG-releasing compound is a compound that contains a photographically useful group and is capable of reacting with an oxidized developing agent to release said group.
  • Such a PUG-releasing compound comprises a carrier moiety and a leaving group, which are linked by a bond that is cleaved upon reaction with oxidized
  • the leaving group contains the PUG, which can be present either as a preformed species, or as a blocked or precursor species that undergoes further reaction after cleavage of the leaving group from the carrier to produce the PUG.
  • the reaction of an oxidized developing agent with a PUG-releasing compound can produce either colored or colorless products.
  • Carrier moieties include hydroquinones, catechols, aminophenols, sulfonamidophenols,
  • a preferred carrier moiety in a PUG-releasing compound is a coupler moiety COUP, which can combine with an oxidized color developer in the cleavage reaction to form a colored species, or dye.
  • the carrier moiety is a COUP
  • the leaving group is referred to as a coupling-off group.
  • the coupling-off group contains the PUG, either as a preformed species or as a blocked or precursor species.
  • the coupler moiety can be ballasted or
  • unballasted It can be monomeric, or it can be part of a dimeric, oligomeric or polymeric coupler, in which case more than one group containing PUG can be contained in the coupler, or it can form part of a bis compound in which the PUG forms part of a link between two coupler moieties.
  • the PUG can be any group that is typically made available in a photographic element in an imagewise fashion.
  • the PUG can be a photographic reagent or a photographic dye. A photographic reagent, which upon release further reacts with components in the
  • photographic element as described herein is a moiety such as a development inhibitor, a development
  • a bleach inhibitor for example, a bleach inhibitor, a bleach accelerator, an electron transfer agent, a coupler (for example, a competing coupler, a dye-forming coupler, or a
  • development inhibitor releasing coupler a dye precursor, a dye, a developing agent (for example, a competing developing agent, a dye-forming developing agent, or a silver halide developing agent), a silver complexing agent, a fixing agent, an image toner, a stabilizer, a hardener, a tanning agent, a fogging agent, an
  • ultraviolet radiation absorber an antifoggant, a
  • nucleator a chemical or spectral sensitizer, or a desensitizer.
  • the PUG can be present in the coupling-off group as a preformed species or it can be present in a blocked form or as a precursor.
  • the PUG can be, for example, a preformed development inhibitor, or the development inhibiting function can be blocked by being the point of attachment to the carbonyl group bonded to
  • PUG in the coupling-off group examples are a preformed dye, a dye that is blocked to shift its
  • a PUG-releasing compound can be described by the formula CAR-(TIME) n -PUG, wherein (TIME) is a linking or timing group, n is 0, 1, or 2, and CAR is a carrier moiety from which is released imagewise a PUG (when n is 0) or a PUG precursor (TIME) 1 -PUG or (TIME) 2 -PUG (when n is 1 or 2) upon reacting with oxidized developing agent. Subsequent reaction of (TIME) 1 -PUG or (TIME) 2 -PUG
  • TIME Linking groups
  • the (TIME) groups can be the same or different.
  • Suitable linking groups which are also known as timing groups, are shown in U.S. Patent Nos. 5,151,343;
  • linking groups are p- hydroxphenylmethylene moieties, as illustrated in the previously mentioned U.S. Patent Nos. 4,409,323;
  • TIME When TIME is joined to a COUP, it can be bonded at any of the positions from which groups are released from couplers by reaction with oxidized color developing agent.
  • TIME is attached at the coupling position of the coupler moiety so that, upon reaction of the coupler with oxidized color developing agent, TIME, with attached groups, will be released from COUP.
  • TIME can also be in a non-coupling position of the coupler moiety from which it can be displaced as a result of reaction of the coupler with oxidized color developing agent. In the case where TIME is in a
  • non-coupling position of COUP other groups can be in the coupling position, including conventional coupling off groups. Also, the same or different inhibitor moieties from those described in this invention can be used.
  • COUP can have TIME and PUG in each of a coupling position and a non-coupling position.
  • compounds useful in this invention can release more than one mole of PUG per mole of coupler.
  • TIME can be any organic group which will serve to connect CAR to the PUG moiety and which, after
  • cleavage from CAR will in turn be cleaved from the PUG moiety.
  • This cleavage is preferably by an intramolecular nucleophilic displacement reaction of the type described in, for example, U.S. Patent No. 4,248,962, or by
  • intramolecular nucleophilic displacement reaction refers to a reaction in which a nucleophilic center of a compound reacts directly, or indirectly through an intervening molecule, at another site .on the compound, which is an
  • electrophilic center to effect displacement of a group or atom attached to the electrophilic center.
  • Such compounds have both a nucleophilic group and an
  • the nucleophilic group and the electrophilic group are located in the compound so that a cyclic organic ring, or a transient cyclic organic ring, can be easily formed by an intramolecular reaction involving the nucleophilic center and the electrophilic center.
  • Timing groups are represented by the structure: wherein:
  • Nu is a nucleophilic group attached to a position on CAR from which it will be displaced upon reaction of CAR with oxidized developing agent;
  • E is an electrophilic group attached to an inhibitor moiety as described and is displaceable therefrom by Nu after Nu is displaced from CAR;
  • LINK is a linking group for spatially relating Nu and E, upon displacement of Nu from CAR, to undergo an intramolecular nucleophilic displacement reaction with the formation of a 3- to 7-membered ring
  • a nucleophilic group is defined herein as a group of atoms one of which is electron rich. Such an atom is referred to as a nucleophilic center.
  • electrophilic group (E) is defined herein as a group of atoms, one of which is electron deficient. Such an atom is referred to as an electrophilic center.
  • the timing group can contain a nucleophilic group and an electrophilic group, which groups are spatially related with respect to one another by a linking group so that, upon release from CAR, the nucleophilic center and the electrophilic center will react to effect displacement of the PUG moiety from the timing group.
  • the nucleophilic center should be prevented from reacting with the electrophilic center until release from the CAR moiety, and the electrophilic center should be resistant to external attack, such as hydrolysis.
  • Premature reaction can be prevented by attaching the CAR moiety to the timing group at the nucleophilic center or an atom in conjunction with a nucleophilic center, so that cleavage of the timing group and the PUG moiety from CAR unblocks the nucleophilic center and permits it to react with the electrophilic center, or by positioning the nucleophilic group and the electrophilic group so that they are prevented from coming into reactive proximity until release.
  • the timing group can contain additional
  • substituents such as additional photographically useful groups (PUGs), or precursors thereof, which may remain attached to the timing group or be released.
  • the groups should be spatially related after cleavage from CAR so that they can react with one another.
  • the nucleophilic group and the electrophilic group are spatially related within the timing group so that the intramolecular nucleophilic displacement reaction
  • thermodynamics should be such and the groups be so selected that an overall free energy decrease results upon ring closure, forming the bond between the
  • nucleophilic group and the electrophilic group breaking the bond between the electrophilic group and the PUG.
  • nucleophilic group, linking group, and electrophilic group will yield a thermodynamic relationship favorable to breaking of the bond between the electrophilic group and the PUG moiety.
  • Representative Nu groups contain electron rich oxygen, sulfur and nitrogen atoms.
  • Representative E groups contain electron deficient carbonyl, thiocarbonyl, phosphonyl and thiophosphonyl moieties. Other useful Nu and E groups will be apparent to those skilled in the art.
  • the linking group can be an acyclic group such as alkylene, for example, methylene, ethylene or
  • LINK is alkylene or arylene.
  • the groups Nu and E are attached to LINK to provide, upon release of Nu from CAR, a favorable spatial relationship for nucleophilic attack of the nucleophilic center in Nu on the electrophilic center in E.
  • LINK is a cyclic group, Nu and E can be attached to the same or adjacent rings .
  • Aromatic groups in which Nu and E are attached to adjacent ring positions are particularly preferred LINK groups .
  • TIME can be unsubstituted or substituted.
  • the substituents can be those which will modify the rate of reaction, diffusion, or displacement, such as halogen, including fluoro, chloro, bromo, or iodo, nitro, alkyl of 1 to 20 carbon atoms, acyl, such as carboxy,
  • sulfoalkyl alkanesulfonamido, and alkylsulfonyl, solubilizing groups, ballast groups and the like, or they can be substituents which are separately useful in the photographic element, such as a stabilizer, an
  • solubilizing groups will increase the rate of diffusion; ballast groups will decrease the rate of diffusion; electron withdrawing groups will decrease the rate of displacement of the PUG.
  • the term "electron transfer down a conjugated chain” is understood to refer to transfer of an electron along a chain of atoms in which alternate single bonds and double bonds occur.
  • conjugated chain is understood to have the same meaning as commonly used in organic chemistry. This further includes TIME groups capable of undergoing fragmentation reactions where the number of double bonds is zero.
  • Electron transfer down a conjugated chain is described in, for example, U.S. Patent No. 4,409,323.
  • Useful TIME moieties can have a finite half-life or an extremely short half-life. The half-life is controlled by the specific structure of the TIME moiety, and may be chosen so as to best optimize the photographic function
  • TIME moiety half-lives of from less than 0.001 second to over 10 minutes are known in the art. TIME moieties having a half-life of over 0.1 second are often preferred for use in PUG-releasing compounds that yield development inhibitor moieties, although use of TIME moieties with shorter half-lives to produce development inhibitor moieties is known in the art.
  • the TIME moiety may either spontaneously liberate a PUG after being released from CAR, or may liberate PUG only after a further reaction with another species present in a process solution, or may liberate PUG during contact of the photographic element with a process solution.
  • Couplers which form cyan dyes upon reaction with oxidized color developing agents are described in such representative patents and publications as: U.S.
  • Couplers which form magenta dyes upon reaction with oxidized color developing agent are described in such representative patents and publications as: U.S. Patent Nos. 2,600,788; 2,369,489; 2,343,703; 2,311,082; 3,152,896; 3,519,429; 3,062,653; 2,908,573, "Farbkuppler- niethacil- effet Literaturubersicht,” published in Agfa Mitanderen, Band III, pp. 126-156 (1961), and Section VII D of
  • couplers are pyrazolones or
  • Couplers which form yellow dyes upon reaction with oxidized and color developing agent are described in such representative patents and publications as: U.S. Patent Nos. 2,875,057; 2,407,210; 3,265,506; 2,298,443; 3,048,194; 3,447,928, "Farbkuppler-eine
  • Couplers which form colorless products upon reaction with oxidized color developing agent are
  • couplers are cyclic carbonyl-containing compounds which react with oxidized color developing agents but do not form dyes.
  • PUG groups that are useful in the present invention include, for example:
  • Useful development inhibitors are iodide and heterocyclic compounds such as mercaptotetrazoles, selenotetrazoles, mercaptobenzothiazoles, selenobenzothiazoles,
  • oxadiazoles benzotriazoles, benzodiazoles, oxazoles, thiazoles, diazoles, triazoles, thiadiazoles,
  • oxathiazoles thiatriazoles, tetrazoles, benzimidazoles, indazoles, isoindazoles, mercaptooxazoles,
  • G is S, Se, or Te, S being preferred.
  • R 2a , R 2d , R 2h , R 2i , R 2j , R 2k , R 2q and R 2r are individually hydrogen, substituted or unsubstituted alkyl, straight chained or branched, saturated or
  • unsaturated, of 1 to 8 carbon atoms such as methyl, ethyl, propyl, butyl, 1-ethylpentyl, 2-ethoxyethyl, t-butyl or i-propyl; alkoxy or alkylthio, such as
  • alkyl esters such as CO 2 CH 3 , CO 2 C 2 H 5 , CO 2 C 3 H7, CO 2 C 4 H 9 ,
  • R 2s is substituted or unsubstituted aryl, or a substituted or unsubstituted heterocyclic group; substituted or
  • unsubstituted benzyl such as methoxy-, chloro-, nitro-, hydroxy-, carboalkoxy-, carboaryloxy-, keto-, sulfonyl-, sulfenyl-, sulfinyl-, carbonamido-, sulfonamido-,
  • R 2a , R 2d , R 2h , R 21 , R 2j , R 2k , R 2q and R 2r may also be a substituted or unsubstituted heterocyclic group selected from groups such as pyridine, pyrrole, furan, thiophene, pyrazole, thiazole, imidazole, 1,2,4-triazole, oxazole,
  • R 2b , R 2c , R 2e , R 2f , and R 2g are as described for R 2a , R 2d , R 2h , R 2i , R 2j , R 2k , R 2q and R 2r ; or, are individually one or more halogens such as chloro, fluoro or bromo and p is 0, 1, 2, 3 or 4.
  • PUGs which are dyes, or form dyes upon release Suitable dyes and dye precursors include azo, azomethine, azophenol, azonaphthol, azoaniline,
  • azopyrazolone indoaniline, indophenol, anthraquinone, triarylmethane, alizarin, nitro, quinoline, indigoid and phthalocyanine dyes or precursors of such dyes such as leuco dyes, tetrazolium salts or shifted dyes.
  • These dyes can be metal complexed or metal complexable.
  • precursors are azo, azomethine, azophenol, azonaphthol, azoaniline, and indoaniline dyes and dye precursors.
  • Suitable azo, azamethine and methine dyes are represented by the formulae in U.S. Patent No. 4,840884, col. 8, lines 1-70.
  • Dyes can be chosen from those described, for example, in J. Fabian and H. Hartmann, Light Absorptlon of Organic Colorants, published by Springer-Verlag Co., but are not limited thereto.
  • Typical dyes are azo dyes having a radical represented by the following formula:
  • X is a hetero atom such as an oxygen atom, a nitrogen atom and a sulfur atom
  • Y is an atomic group containing at least one unsaturated bond having a
  • Z is an atomic group containing at least one unsaturated bond capaole of conjugating with the azo group, and the number of carbon atoms contained in Y and Z is 10 or more.
  • Y and Z are each preferably an aromatic group or an unsaturated heterocyclic group.
  • aromatic group a substituted or unsubstituted phenyl or naphthyl group is preferred.
  • unsaturated heterocyclic group a 4- to 7-membered heterocyclic group containing at least one hetero atom selected from a nitrogen atom, a sulfur atom and an oxygen atom is preferred, and it may be part of a benzene-condensed ring system.
  • the heterocyclic group means groups having a ring structure such as pyrrole, thiophene, furan,
  • Y may be substituted with other groups as well as X and the azo groups.
  • hydrazino group are included. These groups may be further substituted with a group such as those disclosed above repeatedly, for example once or twice.
  • Z is a substituted aryl group or a substituted unsaturated heterocyclic group
  • groups listed as substituents for Y can be used in the same manner for Z.
  • Y and Z contain an aliphatic or alicyclic hydrocarbon moiety as a substituent, any substituted or unsubstituted, saturated, unsaturated or straight or branched groups having, in the case of an aliphatic hydrocarbon moiety, from 1 to 32, preferably from 1 to 20 carbon atoms, and, in the case of an alicyclic
  • hydrocarbon moiety having from 5 to 32, preferably from 5 to 20 carbon atoms, can be used.
  • the uppermost number of carbon atoms of the thus obtained substituent is preferably 32.
  • Y and Z contain an aryl moiety as a substituent, the number of carbon atoms of the moiety is generally from 6 to 10, and preferably it is a
  • acyl group a carbamoyl group, an amino group, a ureido group, a sulfamoyl group, a
  • carbamoylsulfonyl group an urethane group, a sulfonamido group, a hydrazino group, and the like represents
  • hydrocarbon group an alicyclic hydrocarbon group or an aryl group to form mono-, di-, or tri-substituted groups
  • an acylamino group, a sulfonyl group, a sulfonamido group, an acyloxy group and the like each is aliphatic alicyclic, and aromatic group.
  • Couplers released can be nondiffusible color-forming couplers, non-color forming couplers or diffusible competing couplers.
  • Representative patents and publications describing competing couplers are: " On the Chemistry of White Couplers, " by W. Puschel, Agfa-Gevaert AG Mitanderen and der Deutschen staminos-Laboratorium der
  • R 4a is hydrogen or alkylcarbonyl, such as acetyl
  • R 4b and R 4c are individually hydrogen or a
  • solubilizing group such as sulfo, aminosulfonyl, and carboxy
  • R 4d is as defined above and R 4e is halogen, aryloxy, arylthio, or a development inhibitor, such as a mercaptotetrazole, such as phenylmercaptotetrazole or ethylmercaptotetrazole.
  • Developing agents released can be color developing agents, black-and-white developing agents or cross-oxidizing developing agents. They include
  • Structures of suitable developing agents are:
  • R 5a is hydrogen or alkyl of 1 to 4 carbon atoms and R 5b is hydrogen or one or more halogen such as chloro or bromo; or alkyl of 1 to 4 carbon atoms such as methyl, ethyl or butyl groups.
  • R 5b is as defined above.
  • R 5c is hydrogen or alkyl of 1 to 4 carbon atoms and R 5d , R 5e , R 5f , R 5g , and R 5h are individually hydrogen, alkyl of 1 to 4 carbon atoms such as methyl or ethyl; hydroxyalkyl of 1 to 4 carbon atoms such as hydroxymethyl or hydroxyethyl or sulfoalkyl containing 1 to 4 carbon atoms .
  • R 6a is alkyl or aryl of 6 to 20 carbon atoms
  • R 7a is hydrogen, alkyl, such as methyl, ethyl, and butyl, alkoxy, such as ethoxy and butoxy, or
  • alkylthio such as ethylthio and butylthio, for example containing 1 to 6 carbon atoms, and which may be
  • R 7b is hydrogen
  • R 7c , R 7d , R 7e and R 7f are individually hydrogen, substituted or unsubstituted alkyl, or substituted or unsubstituted aryl, such as straight chained or branched alkyl containing 1 to 6 carbon atoms, for example methyl, ethyl and butyl; s is 1 to 6; R 7c and R 7d , or R 7e and R 7f together may form a 5-, 6-, or 7-membered ring.
  • R 7a and R 7D are solubilizing functions by the structure:
  • R 7c , R 7d , R 7e , R 7f , and s are as defined above.
  • PUGs which are electron transfer a ⁇ ents (BTAs) ETAs useful in the present invention are
  • the electron transfer agent pyrazolidinone moieties which have been found to be useful in providing development acceleration function are derived from compounds generally of the type described in U S Patent Nos. 4,209,580;, 4,463,081; 4,471,045; and 4,481,287 and in published Japanese patent application No. 62-123,172.
  • Such compounds comprise 3-pyrazolidinone structures having an unsubstituted or substituted aryl group in the 1-position.
  • Also useful are the combinations disclosed in U.S. Patent No. 4,859,578.
  • these compounds Preferably these compounds have one or more alkyl groups in the 4- or 5-positions of the pyrazolidinone ring.
  • Electron transfer agents suitable for use in this invention are represented by the following two formulas:
  • R 8a is hydrogen
  • R 8b and R 8 c each independently represents hydrogen, substituted or unsubstituted alkyl having from 1 to about 8 carbon atoms (such as hydroxyalkyl), carbamoyl, or substituted or unsubstituted aryl having from 6 to about 10 carbon atoms;
  • R 8d and R 8e each independently represents hydrogen, substituted or unsubstituted alkyl having from 1 to about 8 carbon atoms or substituted or unsubstituted aryl having from 6 to about 10 carbon atoms;
  • R 8f which may be present in the ortho, meta or para positions of the benzene ring, represents halogen, substituted or unsubstituted alkyl hving from 1 to about 8 carbon atoms, or substituted or
  • R 8f substituents can be the same or different or can be taken together to form a carbocyclic or a heterocyclic ring, for example a benzene or an alkylenedioxy ring;
  • t is 0 or 1 to 3.
  • R 8b and R 8c groups are alkyl, it is preferred that they comprise. from 1 to 3 carbon atoms.
  • R 8b and R 8c represent aryl, they are preferably phenyl.
  • R 8d and R 8e are preferably hydrogen.
  • R 8f represents sulfonamido
  • it may be, for example, methanesulfonamido, ethanesulfonamido or
  • DIRRs redox releasers
  • DIRRs useful in the present invention include hydroquinone, catechol, pyrogallol,
  • redox releasers are represented by formula (II) in U.S. Patent No. 4,985,336; col. 3, lines 10 to 25 and formulas (III) and (IV) col.14, line 54 to col. 17, line 11.
  • Other redox releasers can be found in European Patent Application No. 0,285,176. Typical redox releasers include the
  • Couplers containing other suitable redox releasers can be found in for example, U.S. Patent No. 4,985,336; cols. 17 to 62.
  • the following formula represents a 5-, 6-, or 7-membered nitrogen-containing unsaturated heterocyclic group which has 2 to 6 carbon atoms, which is connected to the carrier moiety through the nitrogen atom and which has a sulfonamido group and a development inhibitor group or a precursor thereof, on the ring carbon atoms.
  • Z represents an atomic group necessary to form a 5-, 6-, or 7-membered nitrogen-containing unsaturated heterocyclic ring containing 2 to 6 carbon atoms together with the nitrogen atom;
  • DI represents a development inhibitor group; and R represents a substituent; and DI is
  • the sulfonamido group is connected to a carbon atom of the heterocyclic ring represented by Z, provided that the nitrogen atom through which the heterocyclic group is connected to the carrier moiety and the nitrogen atom in the sulfonamido group are positioned so as to satisfy the Kendall-Pelz rule as described, for example, in The
  • the group represented by the above formula is a group capable of being oxidized by the oxidation product of a developing agent. More specifically, the
  • sulfonamido group thereon is oxidized to a sulfonylimino group from which a development inhibitor is cleaved.
  • the PUG-releasing compound is a development inhibitor-releasing (DIR) compound.
  • DIR development inhibitor-releasing
  • These DIR compounds may be incorporated in the same layer as the emulsions of this invention, in
  • DIR compounds may be among those classified as “diffusable,” meaning that they enable release of a highly transportable inhibitor moiety, or they may be classified as “non-diffusible”, meaning that they enable release of a less transportable inhibitor moiety.
  • the DIR compounds may comprise a timing Or linking group as known in the art.
  • the inhibitor moiety of the DIR compound may be unchanged as the result of exposure to photographic processing solution. However, the inhibitor moiety may change in structure and effect in the manner disclosed in U.K. Patent No. 2,099,167; European Patent Application 167,168; Japanese Kokai 205150/83; or U.S. Patent
  • DIR compounds are dye-forming couplers, they may be incorporated in reactive
  • complementary color sensitized silver halide emulsions as for example a cyan dye-forming DIR coupler with a red sensitized emulsion or in a mixed mode, for example, a yellow dye-forming DIR coupler with a green sensitized emulsion, all known in the art.
  • the DIR compounds may also be incorporated in reactive association with bleach accelerator-releasing couplers, as disclosed in U.S. Patent Nos. 4,912,024 and 5,135,839, and with the bleach accelerator-releasing compounds disclosed in U.S. Patent Nos. 4,865,956 and 4,923,784, all incorporated herein by reference.
  • the dye image-forming compounds and PUG-releasing compounds can be incorporated in
  • photographic element in which the dye image-forming and PUG-releasing compounds are incorporated can be a
  • the monocolor element comprising a support and a single silver halide emulsion layer, or it can be a multicolor, multilayer element comprising a support and multiple silver halide emulsion layers.
  • the above described compounds can be incorporated in at least one of the silver halide emulsion layers and/or in at least one other layer, such as an adjacent layer, where they are in reactive association with the silver halide emulsion layer and are thereby able to react with the oxidized developing agent produced by development of silver halide in the emulsion layer.
  • the silver halide emulsion layers and other layers of the photographic element can contain addenda conventionally contained in such layers.
  • a typical multicolor, multilayer photographic element can comprise a support having thereon a
  • red-sensitized silver halide emulsion unit having
  • Each silver halide emulsion unit can be composed of one or more layers, and the various units and layers can be arranged in different locations with respect to one another, as known in the prior art and as illustrated by layer order formats hereinafter described.
  • a layer or unit affected by PUG can be controlled by incorporating in appropriate locationscns in the element a layer that
  • At least one of the layers of the photographic element can be, for example, a scavenger layer, a mordant layer, or a barrier layer.
  • a scavenger layer for example, a mordant layer, or a barrier layer.
  • a mordant layer for example, a mordant layer, or a barrier layer.
  • additional layers such as antihalation layers, filter layers and the like.
  • the element typically will have a total thickness, excluding the support, of from 5 to 30 m. Thinner formulations of 5 to about 25 m are generally preferred since these are known to provide improved contact with the process solutions. For the same reason, more swellable film structures are likewise preferred. Further, this
  • Suitable dispersing media for the emulsion layers and other layers of elements of this invention are described in Section IX of Research Disclosure, December 1989, Item 308119, and publications therein.
  • the elements of this invention can include additional dye image-forming compounds, as described in Sections VII A-E and H, and additional PUG-releasing compounds, as described in Sections VII A-E and H, and additional PUG-releasing compounds, as described in Sections VII A-E and H, and additional PUG-releasing compounds, as described in Sections VII A-E and H, and additional PUG-releasing compounds, as described in Sections VII A-E and H, and additional PUG-releasing compounds, as
  • the elements of this invention can contain brighteners (Section V), antifoggants and stabilizers (Section VI), antistain agents and image dye stabilizers (Section VII I and J), light absorbing and scattering materials (Section VIII), hardeners (Section X), coating aids (Section XI), plasticizers and lubricants (Section XII), antistatic agents (Section XIII), matting agents (SectionXVI), and development modifiers (Section XXI), all in Re-search Disclosure, December 1989, Item 308119.
  • the elements of the invention can be coated on a variety of supports, as described in Section XVII of Research Disclosure, December 1989, Item 308119, and references cited therein.
  • the elements of this invention can be exposed to actinic radiation, typically in the visible region of the spectrum as described in greater detail hereinafter, to form a latent image and then processed to form a visible dye image, as described in Sections XVIII and XIX of Research Disclosure, December 1989, Item 308119.
  • a color developing agent includes the step of contacting the element with a color developing agent to reduce developable silver halide and oxidize the color developing agent. Oxidized color developing agent in turn reacts with the coupler to yield a dye.
  • Preferred color developing agents are p-phenylenediamines.
  • Especially preferred are 4-amino-3- methyl-N,N-diethylaniline hydrochloride, 4-amino-3- methyl-N-ethyl-N—(methanesulfonamido) ethylaniline sulfate hydrate, 4-amino-3-methyl-N-ethyl-N—
  • hydrochloride and 4-amino-N-ethyl-N-(2-methoxyethyl)m- toluidine di-p-toluenesulfonic acid.
  • the processing step described above provides a negative image.
  • the described elements are preferably processed in the known Kodak Flexicolor C-41 color process as described in, for example, the British Journal of
  • the color development step can be preceded by development with a non-chromogenic developing agent to develop exposed silver halide but not form dye, and then uniform fogging of the element to render unexposed silver halide developable.
  • the Kodak E- 6 Process is a typical reversal process.
  • Table 1 contains the formulas of typical dye image-forming coupler compounds.
  • Table 2 contains the formulas of typical
  • Table 4 provides the formulas of miscellaneous exemplary photographic compounds that can be used in elements of the invention.
  • color photographic elements of this invention can contain any of the optional additional layers and components known to be useful in color
  • photographic elements in general, such as, for example, subbing layers, overcoat layers, surfactants and
  • plasticizers some of which are discussed in detail hereinbefore. They can be coated onto appropriate supports using any suitable technique, including, for example, those described in Research Disclosure, December 1989, Item 308117, Section XV Coating and Drying
  • the photographic elements containing radiation sensitive ⁇ 100 ⁇ tabular grain emulsion layers according to this invention can be imagewise-exposed with various forms of energy which encompass the ultraviolet and visible (e.g., actinic) and infrared regions of the electromagnetic spectrum, as well as electron-beam and beta radiation, gamma ray, X-ray, alpha particle, neutron radiation and other forms of corpuscular and wave-like radiant energy in either noncoherent (random phase) forms or coherent (in phase) forms as produced by lasers.
  • ultraviolet and visible (e.g., actinic) and infrared regions of the electromagnetic spectrum as well as electron-beam and beta radiation, gamma ray, X-ray, alpha particle, neutron radiation and other forms of corpuscular and wave-like radiant energy in either noncoherent (random phase) forms or coherent (in phase) forms as produced by lasers.
  • Exposures can be monochromatic, orthochromatic or
  • panchromatic Imagewise exposures at ambient, elevated or reduced temperatures and/or pressures, including highor low-intensity exposures, continuous or intermittent exposures, exposure times ranging from minutes to
  • microsecond range and solarizing exposures can be employed within the useful response ranges determined by conventional sensitometric techniques, as illustrated by T. H. James, The Theory of the Photographic Process, 4th Ed., Macmillan, 1977, Chapters 4, 6, 17, 18 and 23.
  • a 2030 mL solution containing 1.75% by weight low methionine gelatin (gelatin that has been treated with an oxidizing agent to reduce its methionine content to less than 30 micromoles per gram), 0.011 M sodium chloride and 1.48 x 10 -4 M potassium iodide was provided in a stirred reaction vessel.
  • the contents of the reaction vessel were maintained at 40°C and the pCl was 1.95.
  • the mixture was then held 10 minutes with the temperature remaining at 40°C. Following the hold, a 1.0 M silver nitrate solution and a 1.0 M NaCl solution were then added simultaneously at 2 mL/min for 40 minutes with the pCl being maintained at 1.95.
  • the resulting emulsion was a tabular grain silver iodochloride emulsion containing 0.5 mole percent iodide, based on silver.
  • Fifty percent of total grain projected area was provided by tabular grains having ⁇ 100 ⁇ major faces having an average ECD of 0.84 m and an average thickness of 0.037 m, selected on the basis of an aspect ratio rank ordering of all ⁇ 100 ⁇ tabular grains having a thickness of less than 0.3 m and a major face edge length ratio of less than 10.
  • the selected tabular grain population had an average aspect ratio (ECD/t) of 23 and an average tabularity (ECD/t 2 ) of 657.
  • the ratio of major face edge lengths of the selected tabular grains was 1.4.
  • tabular grains having ⁇ 100 ⁇ major faces and aspect ratios of at least 7.5. These tabular grains had a mean ECD of 0.75 m, a mean thickness of 0.045 m, a mean aspect ratio of 18.6 and a mean
  • This emulsion was precipitated identically to that of Example 1, except no iodide was intentionally added.
  • the resulting emulsion consisted primarily of cubes and very low aspect ratio rectangular grains ranging in size from about 0.1 to 0.5 m in edge length. A small number of large rods and high aspect ratio ⁇ 100 ⁇ tabular grains were present, but did not constitute a useful quantity of the grain population.
  • a color photographic element of the present invention can comprise a single radiation-sensitive emulsion layer on a support.
  • the element can contain a radiation-sensitive layer coated on each side of a support, a so-called duplitized format.
  • multicolor multilayer elements that contain a red light-sensitized, a green light-sensitized, and a blue light-sensitized unit, each unit containing at least one dye image-forming compound in reactive association with a radiation- sensitive silver halide emulsion.
  • the color photographic element of the invention can be used in conjunction with an applied magnetic layer as described in Research Disclosure, November 1992, Item 34390 published by Kenneth Mason Publications, Ltd., Dudley Annex, 12a North Street, Emsworth, Hampshire P010 7DQ, ENGLAND.
  • antihalation layers which are applied in immediate proximity to, and on either side of, the support.
  • protective overcoat layers which can contain gelatin, dyes, ultraviolet light absorbers, polymeric beads, and the like, and are applied above the uppermost dye image-forming unit.
  • red-sensitized, cyan dye image-forming silver halide emulsion unit is situated nearest the support;
  • the green-sensitized, magenta dye image- forming unit next in order is the green-sensitized, magenta dye image- forming unit, followed by the uppermost blue-sensitized, yellow dye image-forming unit.
  • the image-forming units are typically separated from each other by interlayers, as shown.
  • Each of the image-forming units can contain a single radiation-sensitive silver halide emulsion layer.
  • each unit can independently contain two or three layers of differing sensitivity, referred to, respectively, as slow, fast or slow, medium, fast in order of increasing radiation sensitivity.
  • a tabular silver chloride emulsion containing grains bounded by ⁇ 100 ⁇ major faces and in reactive association with a dye image- forming compound and a PUG-releasing compound can be contained in the blue-sensitized silver halide emulsion unit only, or it can be contained in each of the silver halide emulsion units.
  • the tabular silver chloride emulsion containing grains bounded by ⁇ 100 ⁇ major faces and in reactive association with a dye image- forming compound and a PUG-releasing compound can be contained in the blue-sensitized silver halide emulsion unit only, or it can be contained in each of the silver halide emulsion units.
  • chloride emulsion can be in the layer of lowest
  • the slow layer or it can be in other or all the emulsion layers in the unit.
  • the blue-sensitized, yellow dye image-forming silver halide unit is situated nearest the support, followed next by the red-sensitized, cyan dye image- forming unit, and uppermost the green-sensitized, magenta dye image-forming unit.
  • the individual units are typically separated from one another by interlayers .
  • each of the image-forming units can comprise a single radiation- sensitive layer, or each can independently include two (slow, fast) or three (slow, medium, fast) silver halide emulsion layers of differing sensitivity.
  • a tabular silver chloride emulsion containing grains bounded by ⁇ 100 ⁇ major faces can be located in the blue-sensitized silver halide emulsion unit only, or it can be in each of the units. Where a unit comprises more than one radiation-sensitive layer, the tabular silver chloride emulsion can be in the layer of lowest sensitivity, or in other or all of the layers in the unit.
  • a slower red-sensitized silver halide emulsion layer of the cyan dye image-forming unit is situated nearest the support, followed in order by a slower green- sensitized silver halide emulsion layer of the magenta dye image-forming unit, a fast red-sensitized silver halide emulsion layer of the cyan dye image-forming unit, and a fast green-sensitized silver halide emulsion layer of the magenta dye image-forming unit.
  • Uppermost is the blue-sensitized yellow dye image-forming silver halide emulsion unit, which can comprise one, two, or three emulsion layers.
  • image-forming units are typically separated from each other by interlayers.
  • Elements of the present invention having the layer order shown in Structure III can contain tabular silver chloride emulsions having grains bounded by ⁇ 100 ⁇ major faces in the slow emulsion layer of the yellow dye image-forming unit, as well as in the faster emulsion layers of this unit.
  • Tabular silver halide emulsions can also be employed in the layers of lowest sensitivity in the green- and/or red-sensitized emulsion units, as well as in all of the other radiation- sensitive layers of the element.
  • STRUCTURE IVa wherein the slower silver halide emulsion layers of the red-sensitized and the green-sersitized emulsion units are separated from the fast silver halide emulsion layers of these units by the blue-sensitized emulsion unit, which can comprise one, two, or three emulsion layers.
  • the blue-sensitized emulsion unit which can comprise one, two, or three emulsion layers.
  • emulsions with silver halide grains bounded by ⁇ 100 ⁇ major faces can be employed in the overlying fast layers in the green- and red-sensitized silver halide emulsion units, as well as in the blue-sensitized silver halide emulsion unit, or they can be used in all of the radiation-sensitive layers of the element.
  • Structure IVb A variant of Structure IVa is Structure IVb
  • the positions of the slower and the fast silver halide emulsion layers are transposed in both the red-sensitized and in the green-sensitized emulsion units; i.e., the positions of the slower and the fast green-sensitized emulsion layers are reversed from their positions in Structure IVa, as are the positions of the red-sensitized emulsion layers.
  • the emulsions with tabular ⁇ 100 ⁇ -faced silver chloride grains can be situated in the overlying slower layers in the green- and red-sensitized silver halide emulsion units, or they can be utilized in all of the radiation-sensitive layers of the element.
  • Control silver halide emulsions and tabular silver chloride emulsions bounded by ⁇ 100 ⁇ major faces in accordance with the present invention were prepared and sensitized as described below.
  • the emulsions and a summary of their characteristics are listed in Table 5.
  • the cubic silver iodobromide emulsions were prepared by the procedures contained in Section I of Research Disclosure, Item 308119, December 1989.
  • Sensitization was carried out by methods known in the art.
  • Solution 1 was charged into a reaction vessel equipped with a stirrer.
  • Solution 2 was added to the reaction vessel. While the mixture, which was at a pH of 6.0 and a temperature of 40C, was vigorously stirred, Solution 3 and Solution 4 were added at 80 mL/min. for 0.5 minute. The VAg was adjusted to 175 mV, and the mixture was held for ten minutes. Following this hold, Solution 3 and Solution 4 were added simultaneously at 24 mL/in. for 40 minutes; then the flow was linearly
  • Solution 5 was added and stirred for 5 minutes. The pH was then adjusted to 3.8, and the gel was allowed to settle while the temperature was lowered to 15C. The liquid layer was decanted, and the depleted volume was restored with distilled water. The pH was adjusted to 4.5, and the mixture held at 40C for 5 minutes before the pH was adjusted to 3.8 and the settling and decanting steps were repeated. Solution 6 was added, and the pH and VAg were adjusted to 5.6 and 130 mV, respectively.
  • the resulting emulsion contained tabular silver chloride grains having predominantly ⁇ 100 ⁇ faces, an average equivalent circular diameter (ECD) of 1.2 m, and an average thickness of 0.12 m.
  • ECD average equivalent circular diameter
  • the emulsion thus produced was sensitized to green light by treating it with 1 percent NaBr, holding for 5 minutes, adding spectral sensitizing dyes SS-22 and
  • Distilled water 1000 gm Solution 1 was charged into a reaction vessel equipped with a stirrer at 40C.
  • Solution 2 was added to the reaction vessel, and the pH was adjusted to 5.7.
  • the resulting emulsion contained tabular silver chloride grains having predominantly ⁇ 100 ⁇ faces, and average equivalent circular diameter (ECD) of 1.4 m, and an average thickness of 0.14 m.
  • ECD average equivalent circular diameter
  • the emulsion thus produced was sensitized to green light by treating it with 1 percent NaBr, holding for 5 minutes, adding spectral sensitizing dyes SS-22 and SS-26 at a 3:1 ratio, holding for 10 minutes, adding Na 2 S 2 O 3 5H 2 O at 1.0 mg per mol and KAuCI 4 at 1.3 mg per mol, and heating for 10 minutes at 60C to produce EM-5.
  • red light sensitized emulsion EM-8 was obtained using spectral sensitizing dyes SS-25 and SS-23 at a 1:2 ratio
  • blue light sensitized emulsion EM-11 was obtained using spectral sensitizing dye SS-1.
  • the flow rates of the 0.67 M silver nitrate solution and the 0.67 M sodium chloride solution were linearly increased from 20 to 80 mL/min, 150 mL/min, and 240 mL/min in 25 minute intervals.
  • the flow rate of the 0.5 percent gelatin reactant was maintained constant at 500 mL/min.
  • the continuous reactor in which these reactants were premixed was kept at 30°C and a pCl of 2.45, while the growth reactor was maintained at a temperature of 65°C, a pCl of 2.15, and a pH of 6.5.
  • the tabular grain population had an average aspect ratio of 15.5 and an average tabularity of 93.7.
  • This emulsion was sensitized to red light by
  • Sample 101 was prepared by applying the following layers to a clear support in the order
  • Layer 2 (light sensitive layer) comprising 0.32 g of EM-1c, 0.54 g of image dye forming coupler C-1 and 1.54 g gelatin.
  • Layer 3 (protective layer) comprising 2.15 g of gelatin.
  • the layers additionally comprised alpha-4- nonylphenyl-omega-hydroxy-poly(oxy-(2-hydroxy-1,3- propanediyl)) and (para-t-octylphenyl)-di(oxy-1,2- ethanediyl)-sulfonate as surfactants.
  • This film was hardened at coating with 2% by weight to total gelatin of bis-vinylsulfonylmethane.
  • Sample 102 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-2c.
  • Sample 103 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-3c.
  • Sample 104 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-4.
  • Sample 105 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-5.
  • Sample 106 was prepared like sample 105 except that image dye forming coupler C-1 was replaced by 0.32 g of image dye forming coupler C-2.
  • Sample 107 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-6c.
  • Sample 108 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-7.
  • Sample 109 was prepared like sample 101 except that emulsion EM-1cc was replaced by an equal quantity of emulsion EM-8.
  • Sample 110 was prepared like sample 101 except that emulsion EM-1c was replaced by an equal quantity of emulsion EM-9c and image dye-forming coupler C-1 was replaced by 1.08 g of image dye-forming coupler C-3.
  • Sample 111 was prepared like sample 110 except that emulsion EM-9c was replaced by an equal quantity of emulsion EM-10.
  • Sample 112 was prepared like sample 110 except that emulsion EM-9c was replaced by an equal quantity of emulsion EM-11.
  • Coupler C-1 is a cyan image dye-forming
  • Coupler C-2 is a magenta image dye-forming coupler; and C-3 is a yellow image dye-forming coupler.
  • the couplers were provided as photographic coupler dispersions, as known in the art.
  • Samples 101-112 were exposed to white light through a graduated density test object and processed using the KODAK C-41 process.
  • the process was modified in that the bleach solution comprised ferric
  • the photographic sensitivity was measured as the exposure required to enable a Status M density of 0.15 above Dmin after processing.
  • the Status M density at a Dmax value was also measured.
  • the sensitivity is a linear function of grain surface area; and the Status M dye density formed at Dmax per gram of coupler coated per square meter per gram of silver per square meter in each sample, i.e., the normalized dye-density yield (DDY) .
  • control samples 101, 102 and 103 illustrate the difficulty of achieving either high photographic sensitivity or high values of dye- density yield with cubic shaped ⁇ 100 ⁇ AgCl grains.
  • grain size and surface area
  • photographic sensitivity hardly increases at all while dye density yield falls dramatically.
  • the photographic sensitivity would be expected to increase directly as a function of surface area per grain for spectrally
  • samples 104 and 105 of the invention showed photographic sensitivity greatly exceeding that expected based on relative grain surface area. Moreover, the dye density yield achieved in these samples exceeded that available from even less
  • sample 106 of the invention demonstrates that both the sensitivity and dye density yield can be further improved by choosing image
  • Coupler C-2 is a 2-equivalent image coupler; coupler C-1 is a 4-equivalent image coupler, or by choosing an image coupler that forms a high extinction image dye.
  • samples 107 through 109 and from samples 110 through 112 show that these beneficial effects were also obtained from samples of the invention that are sensitive to red and blue light, respectively.
  • the photographic samples according to this invention provide not only greatly improved photographic sensitivity compared to the control samples but also provide surprisingly high dye density formation relative to the control samples.
  • Changes in contact time of a photographic material with a processing solution are typically
  • Control samples 201 through 205 were prepared by applying the following layers to a clear support in the order indicated. Quantities of components are
  • Layer 1 (antihalation layer) comprising gray silver and gelatin.
  • Layer 2 (light sensitive layer) comprising 0.54 g of
  • Layer 3 (protective layer) comprising 2.15 g of gelatin.
  • the layers additionally comprised alpha-4- nonylphenyl-omega-hydroxy-poly (oxy-(2-hydroxy-1,3- propanediyl)) and (para-t-octylphenyl)-di(oxy-1,2- ethanediyl)-sulfonat- as surfactants. These films were hardened at coating with 2% by weight to total gelatin of bis-vinylsulfonylmethane.
  • Control samples 206 through 211 were prepared like samples 201 - 205, except that emulsion EM-i3c was replaced by an equal weight of emulsion EM-14c.
  • Control samples 301 through 303 were prepared like samples 201 - 205, except that emulsion EM-13c was replaced by an equal weight of emulsion EM-6c.
  • Control samples 304 through 306 were prepared like samples 201 - 205, except that emulsion EM-13c was replaced by an equal weight of emulsion EM-9c.
  • Control samples 307 through 311 were prepared like samples 201 - 205, except that emulsion EM-13c was replaced by an equal weight of emulsion EM-12c.
  • Control samples 312 through 315 were prepared like samples 201 - 205, except that emulsion EM-13c was replaced by an equal weight of emulsion EM-3c.
  • Samples 316 through 321 were prepared like samples 201 - 205, except that emulsion EM-13c was replaced by an equal weight of emulsion EM-4.
  • Samples 322 through 329 were prepared like samples 201 - 205, except that emulsion EM-13c was replaced by an equal weight of emulsion EM-4.
  • Samples 201 through 329 were exposed to light through a graduated density test object and processed as color negative films according to the KODAK C-41 process.
  • the process was modified in that the bleach solution comprised ferric propylenediamine-tetraacetate.
  • the useful latitude of each sample was quantified by determining the exposure required to enable a Status M density 0.10 above Dmin and the exposure required to enable a Status M density 0.10 below Dmax for each sample. The larger the difference in exposure, the greater the useful latitude of the sample. Combinations of emulsions and development inhibitor-releasing (DIR) compounds that enable a large increase in latitude can be especially useful.
  • the photographic gamma of each sample was quantified as the rate of change of the Status M density obtained after processing as a function of log exposure, at exposure values towards the center of the samples' useful latitude. Combinations of emulsions and DIR compounds that enable a significant decrease in gamma can also be especially useful.
  • Table 7 lists for each sample: the emulsion identification; the DIR compound identification and amount (in grams per square meter); the relative gamma of the processed element (in each case normalized to the corresponding control sample prepared without a DIR compound); and, the relative latitude of the
  • Samples 201 through 211 contain either cubic or tabular shaped silver iodobromide emulsions similar to those typically employed in combination with DIR
  • Samples 301 through 315 contain cubic shaped silver chloride emulsions known in the art.
  • the results demonstrate that combinations of these cubic silver chloride emulsions with a variety of DIR compounds typically leads to, at best, a very modest increase in useful latitude and a modest reduction in gamma. In some cases latitude was truncated, while in others gamma was increased. This behavior can be related to gross sensitivity losses encountered with these combinations, or to changes in Dmin.
  • Samples 317-321 and 323-329 illustrate the combination of tabular shaped ⁇ 100 ⁇ surface AgCl crystals and DIR compounds, in accordance with the present
  • the elements of the present invention simultaneously enable both larger increases in latitude and greater suppression of gamma than is achieved with combinations of emulsions and DIR compounds that have been optimized over many years by many practitioners of the photographic arts.
  • processing solution are typically employed by those skilled in the photographic art to approximate the effects of changes in temperature or the concentration of components in the processing solution.
  • skilled practioners of the photographic arts are able to choose, in accordance with the present invention, a process time and composition, DIR compound, dye
  • Samples 901 through 969 were prepared generally as described for sample 101 of Example 2. All of these samples were coated on a transparent support. Samples 970 through 972 were coated on a reflective support. All of these elements represent further illustrations of the practice of this invention. The identification and quantity of the silver halide emulsion and the
  • the samples were exposed to light through a graduated density test object and processed using the Kodak C-41 process.
  • the process was modified in that the bleach solution comprised ferric
  • Table 8 shows the identity and quantity of the emulsion and coupler compounds employed in each element.
  • the normalized dye density yield (DDY) observed for each sample and the wavelength band employed (R, G or B) is also shown.
  • Table 8 Normalized dye density (DDY) from
  • Couplers and other compounds are listed in grams per meter squared.
  • Samples 901 through 969 were exposed to white light through a graduated density test object and
  • Samples 401 through 412 were prepared by applying the following layers to a clear support in the order indicated. Quantities of components are expressed in grams per square meter. Layer 1 (antihalation layer) comprising gray silver and gelatin.

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Abstract

Elément photographique couleur doté d'un support recouvert d'au moins une couche d'émulsion sensible aux rayonnements qui comprend un milieu de dispersion et des grains d'halogénure d'argent. Ladite couche d'émulsion est à base d'halogénure d'argent en grains tabulaires et au moins 50 % de la surface totale de projection des grains est constituée de grains tabulaires (a) délimités par des faces majeures [100] ayant des rapports de côtés adjacents inférieurs à 10, (b) chaque grain ayant un rapport entre son diamètre circulaire équivalent et son épaisseur d'au moins 2 et (c) contenant à l'intérieur, au niveau de son site de nucléation, de l'iodure et au moins 50 moles % de chlorure. La couche d'émulsion possède, en association de réaction, un composé formant des couleurs d'image et un composé qui contient un groupe photographiquement utile et est capable de réagir avec un agent de développement oxydé pour libérer ledit groupe. Un procédé de préparation des émulsions à base d'halogénure d'argent à grains tabulaires et sensibles aux rayonnements est également décrit.
PCT/US1993/002604 1993-03-22 1993-03-22 Elements photographiques formant une image couleur WO1994022054A1 (fr)

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EP93907625A EP0641459B1 (fr) 1993-03-22 1993-03-22 Elements photographiques formant une image couleur
JP52097094A JP3333518B2 (ja) 1993-03-22 1993-03-22 色素画像形成性写真要素
PCT/US1993/002604 WO1994022054A1 (fr) 1993-03-22 1993-03-22 Elements photographiques formant une image couleur
DE69326000T DE69326000T2 (de) 1993-03-22 1993-03-22 Ein farbbild erzeugende photographische elemente

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5665530A (en) * 1994-08-30 1997-09-09 Fuji Photo Film Co., Ltd. Silver halide emulsion and photographic material using the same
US5707793A (en) * 1995-04-19 1998-01-13 Fuji Photo Film Co., Ltd. Silver halide emulsion and silver halide photographic material using the same
US6051359A (en) * 1996-11-25 2000-04-18 Fuji Photo Film Co., Ltd. Heat developable light-sensitive material and method of forming color images
US6218095B1 (en) 1996-10-28 2001-04-17 Fuji Photo Film Co., Ltd. Silver halide color photographic photosensitive material

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4063951A (en) * 1974-12-19 1977-12-20 Ciba-Geigy Ag Manufacture of tabular habit silver halide crystals for photographic emulsions
EP0369424A1 (fr) * 1988-11-15 1990-05-23 Fuji Photo Film Co., Ltd. Matériau photographique photosensitif à l'halogénure d'argent
US5176992A (en) * 1992-01-13 1993-01-05 Eastman Kodak Company Process for the preparation of a grain stabilized high chloride tabular grain photographic emulsion (II)
WO1993006521A1 (fr) * 1991-09-24 1993-04-01 Eastman Kodak Company Emulsions de stabilite exceptionnelle fortement chlorurees, a haute tabularite

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4063951A (en) * 1974-12-19 1977-12-20 Ciba-Geigy Ag Manufacture of tabular habit silver halide crystals for photographic emulsions
EP0369424A1 (fr) * 1988-11-15 1990-05-23 Fuji Photo Film Co., Ltd. Matériau photographique photosensitif à l'halogénure d'argent
WO1993006521A1 (fr) * 1991-09-24 1993-04-01 Eastman Kodak Company Emulsions de stabilite exceptionnelle fortement chlorurees, a haute tabularite
US5176992A (en) * 1992-01-13 1993-01-05 Eastman Kodak Company Process for the preparation of a grain stabilized high chloride tabular grain photographic emulsion (II)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5665530A (en) * 1994-08-30 1997-09-09 Fuji Photo Film Co., Ltd. Silver halide emulsion and photographic material using the same
US5707793A (en) * 1995-04-19 1998-01-13 Fuji Photo Film Co., Ltd. Silver halide emulsion and silver halide photographic material using the same
US6218095B1 (en) 1996-10-28 2001-04-17 Fuji Photo Film Co., Ltd. Silver halide color photographic photosensitive material
US6228565B1 (en) 1996-10-28 2001-05-08 Fuji Photo Film Co., Ltd. Silver halide color photographic photosensitive material
US6232055B1 (en) 1996-10-28 2001-05-15 Fuji Photo Film Co., Ltd. Silver halid color photographic photosensitive material
US6051359A (en) * 1996-11-25 2000-04-18 Fuji Photo Film Co., Ltd. Heat developable light-sensitive material and method of forming color images

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EP0641459B1 (fr) 1999-08-11
DE69326000D1 (de) 1999-09-16
DE69326000T2 (de) 2000-02-17
JPH07507645A (ja) 1995-08-24
EP0641459A1 (fr) 1995-03-08
JP3333518B2 (ja) 2002-10-15

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