Abstract: The invention disclosed is a photographic element comprising a support bearing at least one silver halide emulsion and at least one high-boiling solvent of structure I, below: ##STR1## wherein: m is 0, 1 or 2;each R.sub.1 is an individually selected alkyl group with up to four carbon atoms;n is 2 to 5;each R.sub.2 and R.sub.3 may be the same or different and is individually selected from hydrogen or an alkyl group with up to four carbon atoms;p is 0 to 3;each R.sub.4 is independently a methyl or ethyl group; andthe sum of the number of carbon atoms in each R.sub.1 plus each R.sub.2 plus each R.sub.3 plus each R.sub.4 taken together is three to seven.

Abstract: Disclosed is a silver halide photographic material having at least one silver halide emulsion layer containing a silver halide photographic emulsion, wherein the silver halide photographic emulsion comprises spectrally sensitized tabular silver halide grains having an average aspect ratio of from 8 to 100, and having light absorption strength by a sensitizing dye per unit surface area of the grain surface of 100 or more.

Abstract: A color negative film is disclosed capable of producing dye images suitable for digital scanning.

Abstract: A silver halide photographic material having on a support at least one light-sensitive emulsion layer which comprises silver halide grains having a silver chloride content of at least 95 mole %: wherein the silver halide grains each have a phase containing silver iodide in a proportion of at least 0.1 mole % for every 1 mole of total silver halides constituting the grains in the surface part situated outside the central part occupying at least 50% of the volume of each grain and, outside of this part, have no silver iodide-free layer or further have a silver iodide-free layer continuously or discontinuously the thickness of which is 0.002 .mu.m or below, and the emulsion layer further comprises a particular benzothiamonomethinecyanine sensitizing dye.

Abstract: An aqueous-based slurry comprising:a particulate solid substance comprising a weak acid functional group having effective pK.sub.a1 >1 and less than 1% by weight aqueous solubility at pH=pK.sub.a1 ;an aqueous continuous phase at pH<pK.sub.a1 +3;a buffering salt of a weak acid, where the weak acid associated with this buffering salt has pK.sub.a2 and wherepK.sub.a1 -2.ltoreq.pK.sub.a2 ;andwhere the incremental molar ionic strength in the continuous phase of said slurry resulting from said buffering salt is less than 0.04 mol/L is disclosed.

Abstract: This invention relates to silver halide photographic element comprising a silver halide emulsion chemically sensitized in the presence of an isothiazolin-one compound represented by the formula ##STR1## wherein R.sup.1 is a substituent; and Z is a substituted or unsubstituted saturated ring, wherein the isothiazolin-one compound was added after precipitation of the emulsion.

Abstract: The present invention provides an emulsion of high silver chloride content tabular silver halide grains with {100} planes as main planes having an excellent color sensitizability, gradation and preservability which can be quickly processed and a photographic light-sensitive material comprising such an emulsion. A novel silver halide emulsion is provided, comprising tabular silver halide grains having {100} planes as two main parallel planes, an aspect ratio of from not less than 2 to not more than 15, a silver chloride content of not less than 60 mol % and a silver salt present on the surface thereof more difficultly-soluble than silver chloride, in a proportion of not less than 50% of all the silver halide grains contained therein as calculated in terms of projected area.

Abstract: A black and white photographic element contains a filter dye of Formula (I): ##STR1## wherein each R.sup.1 is independently substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, cyano, hydroxy, carboxy, substituted or unsubstituted amido, or substituted or unsubstituted sulfonamido;n is 1-4;R.sup.2 is H, substituted or unsubstituted alkyl or amido;each of R.sup.3 and R.sup.4 is independently hydrogen or substituted or unsubstituted alkyl; andM is a cation.

Abstract: The present invention concerns a silver halide radiographic product intended for industrial radiography as well as a novel radiographic system and a method for forming the radiographic image.The present invention concerns a photographic product designed to be exposed to X or .gamma. radiation, which comprises a support covered on at least one face with a layer of silver halide emulsion which contains an efficient amount of at least one free spectral sensitizing dye.This product, intended for industrial radiography, exhibits improved contrast.

Abstract: Chemical sensitization of silver halide photothermographic emulsions used in photothermographic elements, can be effected by the decomposition of sulfur containing compounds on or around the surface of the silver halide grains, usually under oxidizing conditions at elevated temperatures. Alignment of the sulfur containing compounds on the surface of the grains, can be accomplished with spectral sensitizing dyes and appears to be particularly effective in providing strong chemical sensitization effects.

Abstract: A color photographic recording material having a film support and, arranged thereon, at least one red-sensitive silver halide emulsion layer containing a cyan coupler, at least one green-sensitive silver halide emulsion layer containing a magenta coupler, at least one blue-sensitive silver halide emulsion layer containing a yellow coupler and optionally further non-photosensitive layers contains, in addition to conventional sensitizing dyes, in at least one of the red-sensitive silver halide emulsion layers thereof and in at least one of the green-sensitive emulsion layers thereof at least one cyanine dye in each layer having an absorption maximum in a methanolic solution in the range from 515 to 550 nm, wherein the absorption maxima of the additional cyanine dye in the red-sensitive silver halide emulsion layer and of the additional cyanine dye in the green-sensitive layer, in each case measured in a methanolic solution, are no more than 10 nm and preferably no more than 5 nm apart.

Abstract: The invention provides a color negative photographic element comprising a transparent support bearing at least two light sensitive silver halide emulsion layers sensitive to blue light, at least two such layers sensitive to green light, and at least two such layers sensitive to red light, wherein at least one of the red sensitive emulsion layers is spectrally sensitized with both a particular first carbocyanine dye (I) which contains both a thiazole and an oxazole ring and a particular second carbocyanine dye (II) which contains two thiazole rings.The element of the invention is advantageous in allowing an increased efficiency of silver removal during the bleaching step of the development process.

Abstract: A silver halide photographic light-sensitive material has at least one silver halide emulsion layer on a support, and contains an imidazole compound. The silver halide emulsion layer contains substantially perfect cubic grains.

Abstract: Disclosed is a silver halide photographic light-sensitive material comprising a support having thereon a light-sensitive silver halide emulsion layer and a layer adjacent to said light-sensitive silver halide emulsion layer, whereinat least one of said layers contains a dye having a maximum absorption at a wavelength being within the range of .+-.

Abstract: A process is disclosed of preparing a high bromide tabular grain emulsion comprising (1) in a grain nucleation step creating in a dispersing medium tabular grain nuclei containing parallel twin planes and (2) in a grain growth step subsequently growing the grain nuclei into tabular grains by running into the dispersing medium high bromide silver halide grains having a maximum equivalent circular diameter of less than 40 nm, wherein (a) the high bromide grains are formed prior to the grain nucleation step and then held in the presence of a grain growth restrainer adsorbed to the grain surfaces to inhibit grain ripening and (b) during the growth step the restrainer is desorbed from the high bromide grains and silver and halide ions forming the high bromide grains are released by ripening into the dispersing medium in the growth step.

Abstract: Solid particle dispersions of compounds useful in imaging elements can be made with substantially improved stability to particle growth by dispersing the compound of interest in the presence of a relatively small amount of a second compound that is structurally similar to the compound of interest. This second compound is combined with the compound of interest prior to dispersing the compound of interest, i.e., prior to milling in the case of milled dispersions, and prior to precipitation in the case of pH or solvent precipitated dispersions. While being distinct, the second compound has a similar chemical structure to the main compound.

Abstract: A photographic silver halide color print material comprising a support and yellow, magenta and cyan dye image forming layer units comprising at least one silver halide emulsion layer and at least one dye image-forming coupler which material contains a total silver halide coating weight less than 150 mg/m.sup.2 (as silver) and wherein the grain size (average volume in cubic microns) of the emulsion(s) is less than 1.0 (.mu.m).sup.3 in the yellow image forming unit and less than 0.125 (.mu.m).sup.3 in the magenta image forming unit and wherein each layer unit of the material has a dye image-forming efficiency (E) under conditions of use of above 30 where: ##EQU1## wherein the emulsion(s) of the cyan dye image forming layer unit have a silver coating weight less than 50 mg/m.sup.2, and an average grain size less than 0.064 (.mu.m).sup.

Abstract: A photographic element is described which comprises a silver halide emulsion having incorporated therein a latent image forming unit, said unit being comprised of an agglomeration of silver halide in conductive contact with a light absorbing center, wherein the center is comprised of:(i) an amorphous or liquid crystalline spectral sensitizing dye; or(ii) a plurality of spectral sensitizing dye crystals.Also described is a process for forming a silver halide emulsion and the emulsion prepared by such process.

Abstract: A photographic emulsion is disclosed comprised of a dispersing medium and radiation-sensitive grains with greater than 50 percent of total grain projected area being accounted for by tabular grains comprised of (1) a tabular host portion containing greater than 50 mole percent bromide, based on silver, and having spaced parallel {111} major faces, (2) a first epitaxial phase containing greater than 90 mole percent iodide, based on silver, accounting for less than 60 percent of total silver and overlying from 15 to 90 percent of the major faces, and (3) surface silver halide of a face centered cubic crystal lattice structure overlying at least a portion of the first epitaxial phase.

Abstract: The invention provides a method of treating silver chloride emulsions comprising providing a silver chloride emulsion, adding gold and sulfur chemical sensitizers, heating to chemically sensitize said emulsion, cooling to below about 50.degree. C., adding bromide to the emulsion and then after bromide addition adding spectral sensitizing dye.

Abstract: A silver halide color photographic material having at least one silver halide emulsion layer on a support is color developed after imagewise exposure, followed by desilverization, wherein the photographic material has a total dry film thickness of 8 to 22 .mu.m, the concentration of ammonium ions contained in a processing solution having fixing ability used in desilverization is 0 to 50 mol % based on the total cations, and the processing solution having fixing ability contains at least one kind of thioether compound, thereby improving desilverization performance in continuous processing and preventing yellow stains from increasing.

Abstract: A silver halide photographic light-sensitive material having at least one light-sensitive silver halide emulsion layer on a support is disclosed. The light-sensitive silver halide emulsion layer contains tabular silver halide grains having an average aspect ratio of 2 or more and contains a compound represented by the following formula (I) and/or the oxidized product thereof:X.sub.1 --A--X.sub.2 Formula (I)wherein X.sub.1 and X.sub.2 each represent OR.sub.1 or ##STR1## wherein R.sub.1 represents a hydrogen atom or a group capable of being converted to a hydrogen atom upon hydrolysis, and R.sub.2 and R.sub.3 each represent hydrogen, alkyl, aryl, heterocyclic, heterocyclic sulfonyl, heterocyclic carbonyl, sulfamoyl, or carbamoyl, A represents arylene, and at least one of the groups representative of X.sub.1, X.sub.2, and A is substituted by a group which accelerates adsorption to a silver halide grain.

Abstract: The invention is directed to a process for preparation of a silver halide emulsion comprising providing an unsensitized emulsion, heating to carry out chemical sensitization of said emulsion, cooling said emulsion, heating said emulsion a second time to complete heat treatment.

Abstract: An improved spectrally sensitized ultrathin tabular grain emulsion is disclosed in which tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, (e) exhibiting an average thickness of less than 0.07 .mu.m, and (f) having latent image forming chemical sensitization sites on the surfaces of the tabular grains, are spectrally sensitized and improved by employing dump iodide host tabular grains and, in forming the surface chemical sensitization sites, at least one silver salt epitaxially located on the tabular grains.

Abstract: A silver halide black and white photographic light-sensitive material is disclosed, comprising a support having thereon two silver halide emulsion layers, wherein a silver halide emulsion layer provided further from the support contains tabular silver halide grains having an aspect ratio of not less than 3, another silver halide emulsion layer containing silver halide grains having an aspect ratio of not more than 2.5; both silver halide grain emulsions are each spectrally sensitized by adding thereto a spectral-sensitizing dye in the form of a dispersion of solid particles dispersed in an aqueous medium.

Abstract: A chemically and spectrally sensitized ultrathin tabular grain emulsion is disclosed including tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, and (e) exhibiting an average thickness of less than 0.07 .mu.m.It has been observed that increased speed and contrast as well as improvements in speed-granularity relationships can be realized when the surface chemical sensitization sites include epitaxially deposited silver halide protrusions forming epitaxial junctions with the tabular grains, the protrusions (a) being located on up to 50 percent of the surface area of the tabular grains, (b) having a higher overall solubility than at least that portion of the tabular grains forming epitaxial junctions with the protrusions, and (c) forming a face centered cubic crystal lattice.

Abstract: Spectrally sensitized tabular grain emulsions are disclosed exhibiting (1) increased speeds and (2) contrasts and speed-granularity relationships superior to those of conventional emulsions of the same average grain sizes. The tabular grains have {111} major faces, contain greater than 80 mole percent bromide, based on silver, and are substantially free of iodide, exhibit an average aspect ratio of greater than 50 and an average equivalent circular diameter of >10 micrometers, account for greater than 90 percent of total grain projected area, and have latent image forming chemical sensitization sites on their surfaces including epitaxially deposited silver halide protrusions of a face centered cubic rock salt crystal lattice structure forming epitaxial junctions with the tabular grains. The protrusions are restricted to those portions of the tabular grains (a) located nearest peripheral edges of and (b) accounting for less than 50 percent of the {111} major faces of the tabular grains.

Abstract: Spectrally sensitized tabular grain emulsions are disclosed exhibiting increased speeds and speed-granularity relationships superior to those of conventional emulsions of the same average grain sizes. The tabular grains have {111} major faces, contain greater than 70 mole percent bromide and from 0.25 to 10 mole percent iodide, based on silver, exhibit an average aspect ratio of greater than 50 and an average equivalent circular diameter of >10 micrometers, account for greater than 90 percent of total grain projected area, and have latent image forming chemical sensitization sites on their surfaces including epitaxially deposited silver halide protrusions of a face centered cubic rock salt crystal lattice structure forming epitaxial junctions with the tabular grains.

Abstract: A radiation-sensitive high bromide {111} tabular grain emulsion is disclosed in which at least 90 percent of silver halide epitaxy of an isomorphic face centered cubic crystal lattice structure containing at least 1 mole percent iodide is deposited on the {111} major faces in the form of monocrystalline terraces. Each epitaxial terrace is grown from a nucleation site along an edge of a {111} major face inwardly, with terraces overlying less than 25 percent of the {111} major faces. Surprisingly, these emulsions exhibit higher photographic speeds than those produced by growing silver halide epitaxy outwardly as protrusions from the corners or edges of the tabular grains.

Abstract: A radiation-sensitive spectrally sensitized tabular grain emulsion is disclosed which exhibits improved speed and contrast. The tabular grains have {111} major faces, contain greater than 70 mole percent bromide and up to 10 mole percent iodide, based on silver, account for greater than 90 percent of total grain projected area, and have an average equivalent circular diameter of at least 3.5 .mu.m. The tabular grains have latent image forming chemical sensitization sites on their surfaces including epitaxially deposited silver halide protrusions of a face centered cubic rock salt crystal lattice structure forming epitaxial junctions with the tabular grains.

Abstract: A photographic emulsion is disclosed comprised of a dispersing medium and radiation-sensitive silver halide grains with greater than 50 percent of total grain projected area being accounted for by grains containing a host portion of a face centered cubic rock salt crystal lattice structure and a first epitaxial phase containing greater than 90 mole percent iodide. The host portion is tabular, being bounded by an exterior having first and second parallel major faces joined by a peripheral edge. The first epitaxial phase accounts for less than 60 percent of total silver, and the first epitaxial phase is restricted to a portion of the exterior of the host portion that includes at least 15 percent of the major faces.

Abstract: A light-sensitive silver halide photographic emulsion is disclosed, wherein at least 70% of the total projected area of silver halide grains are tabular grains having an average aspect ratio of a diameter to a thickness of 2 or more, an average value of the longest distances between two or more parallel twin planes contained in the respective tabular grains is 0.008 .mu.m or more, and a variation coefficient of the longest distances between parallel twin planes is 35% or less, and wherein the silver halide emulsion is spectrally sensitized with a substantially slightly water-soluble sensitizing dye by adding the dye to the emulsion in the form of a dispersion of solid particles dispersed in an aqueous solution substantially free from an organic solvent or surfactant.

Abstract: A silver halide photographic emulsion which comprises silver halide grains having a silver chloride content of at least 60 mol % and an octatetracontahedral crystal form of the kind which is constructed of 48 triangular faces, every one of which contacts convexly with each of its two adjoining faces to form a line and concavely with its one adjoining face to form a line, with the grains being formed in the presence of a synthetic polymer peptizer which contains, as repeating units, units derived from a thioether linkage-containing ethylenically unsaturated monomer, in a mole fraction of from about 20 to 100 mole %, thereby achieving low fog and high sensitivity.

Abstract: An improved image display material comprising high chloride silver halide emulsions having greater than 90 mole % silver chloride, where the material comprises a yellow dye-forming layer sensitive to blue light comprising a high chloride silver halide emusion with a peak spectral sensitivity to blue light less than about 475 nm, preferably from about 440-475 nm, and a coupler dispersion comprising a yellow dye-forming coupler and a water-insoluble polymer. Photographic image display materials with both short-blue sensitivity and a polymer dispersion in the yellow dye-forming blue-sensitive layer show a synergistic improvement in color reproduction in accordance with the invention, providing for color photographic prints with less color error than seen for materials comprising only one of the components. The improvement is most notable for yellow and green colored areas of a color print.

Abstract: A chemically and spectrally sensitized ultrathin tabular grain emulsion is disclosed including tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide and at least 0.25 mole percent iodide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, and (e) exhibiting an average thickness of less than 0.07 .mu.m.

Abstract: A color photographic negative element which has a transparent base and a blue sensitive silver halide emulsion layer. The foregoing blue sensitive layer meets each of the following spectral sensitivity requirements:S.sub.max (426-444 nm) .gtoreq.65%S.sub.max(400-500 nm)IS.sub.(425-450) .gtoreq.25%(IS.sub.(400-500))in which S.sub.max(426-444 nm) is the maximum sensitivity between 426 to 444 nm, S.sub.max(400-500 nm) is the maximum sensitivity between 400-500 nm, IS.sub.(425-450) is the integrated spectral sensitivity of the blue sensitive layer from 425 to 450 nm, and IS.sub.(400-500) is the integrated spectral sensitivity of the blue sensitive layer in the region 400-500 nm. A method for printing a negative obtained from exposing and processing an element of the foregoing type, on automatic printers which automatically compensate for color bias, is also provided.

Abstract: A chemically and spectrally sensitized ultrathin tabular grain emulsion is disclosed including tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide and at least 0.25 mole percent iodide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, and (e) exhibiting an average thickness of less than 0.07 .mu.m.

Abstract: In a silver halide emulsion, tabular silver halide grains substantially consisting of silver bromoiodide, each having faces as two parallel major faces, an aspect ratio of 2 or more, and an average silver iodide content of 1 mol % or more, account for 50% or more of a total projected area of silver halide grains.

Abstract: Disclosed are a silver halide photographic material containing at least one merocyanine color-sensitizing dye having a particular structure of formula (I) ##STR1## wherein R.sub.1 and R.sub.2 each represent an alkyl group having a residue capable of making the compound soluble in water as a free acid or salt; V.sub.1, V.sub.2, V.sub.3 and V.sub.4 each represent a hydrogen atom or a monovalent substituent, provided that these substituents (V.sub.1, V.sub.2, V.sub.3, V.sub.4) are not bonded to each other to form a ring and that the sum of the molecular weights of V.sub.1, V.sub.2, V.sub.3 and V.sub.4 is from 4 to 50; L.sub.1, L.sub.2, L.sub.3 and L.sub.4 each represent an optionally substituted methine group; M.sub.1 represents a charge-neutralizing pair ion; and m.sub.1 represents a number of from 0 to 4 that is necessary for neutralizing the intramolecular charge.

Abstract: Disclosed is a silver halide emulsion in which at least 50% of the total projected area of silver halide grains comprises tabular core/shell grains each having {100} planes as main planes and said silver halide grain substantially comprises silver chlorobromide with the halogen composition continuously being varied in the shell part.

Abstract: A silver halide photographic photosensitive material comprises an emulsion layer which includes silver halide grains having a silver chloride content of at least 50 mol % and containing a rhodium compound. The material also comprises, (i) a hydrazine derivative according to formula (1), (2) or (3) which formulas are shown and defined in the specification, and (ii) at least one compound selected from colloidal silica and polyacrylamide derivatives. The material further comprises a protective layer, the outermost layer of which has a dynamic friction coefficient is not more than 0.35. The material may be processed in a developer having a pH of at least 9.6 but less than 11.0.

Abstract: A silver halide color photographic material is disclosed, comrising a support provided thereon light-sensitive silver halide emulsion layers including a blue-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a red-sensitive silver halide emulsion layer, and a non-image forming layer which is located farther from the support than the light-sensitive silver halide emulsion layers and adjacent to one of the light-sensitive silver halide emulsion layers, wherein a silver halide emulsion contained in the layer adjacent to the non-image forming layer is spectrally sensitized by adding a water-insoluble sensitizing dye in the form of solid particles dispersed in an aqueous medium; and the non-image forming layer contains a substantially light-insensitive silver halide fine grain emulsion having an average grain size of not more than 0.05 .mu.m and an average iodide content of 0.5 to 3.0 mol %.

Abstract: A silver halide photographic material comprising a support having thereon a silver halide emulsion layer which comprises a hydrazine compound having at least one absorbent group to silver halide, wherein two nitrogen atoms of the hydrazine compound are substituted by four substituents and the carbon atoms in the four substituents bonded directly to the two nitrogen atoms are not substituted by an oxo group.

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

Abstract: A chemically and spectrally sensitized ultrathin tabular grain emulsion is disclosed including tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, and (e) exhibiting an average thickness of less than 0.07 .mu.m.Improved sensitivity is observed when the surface chemical sensitization sites include silver halide protrusions of a face centered cubic crystal lattice structure forming epitaxial junctions with the tabular grains and having a higher overall solubility than at least that portion of the tabular grains forming epitaxial junctions with the protrusions and a sensitivity enhancing combination of dopants are contained in the silver halide grains including a first sensitivity enhancing dopant capable of providing shallow electron trapping sites and a second sensitivity enhancing selenium dopant.

Abstract: The invention generally relates to a method of silver halide grain finishing comprising providing a high chloride silver halide grain emulsion and adding a silver bromide fine grain Lippmann emulsion during the chemical sensitization heat cycle for each grain wherein said fine grain emulsion has a photographically useful compound adhered to said fine grain Lippmann emulsion.

Abstract: Improved sensitivity and reduced minimum density are provided by an emulsion in which high bromide tabular grains exhibit an average thickness of less than 0.07 .mu.m and have latent image forming reduction chemical sensitization sites and adsorbed spectral sensitizing dye on their surfaces. The tabular grains contain a dopant capable of forming shallow electron trapping sites, and the spectral sensitizing dye exhibits an oxidation potential more positive than 1.2 volts. A photographic element is disclosed which locates the emulsion in a layer overlying a minus blue recording emulsion layer. Exceptionally sharp images are formed in the minus blue recording emulsion layer when in the overlying emulsion layer greater than 97 percent of the total projected area of the silver halide grains having an equivalent circular diameter of at least 0.2 .mu.m is accounted for by tabular grains having an average equivalent circular diameter of at least 0.7 .mu.m.

Abstract: Radiation sensitive emulsions are disclosed in which surface sensitized silver halide grains are agglomerated into discrete clumps and the clumps are separated by peptizer. The emulsions exhibit a higher sensitivity than emulsions in which grains of the same mean size are individually separated by peptizer.

Abstract: A chemically and spectrally sensitized ultrathin tabular grain emulsion is disclosed including tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, and (e) exhibiting an average thickness of less than 0.07 .mu.m.It has been observed that increased speed and contrast as well as improvements in speed-granularity relationships can be realized when the surface chemical sensitization sites include epitaxially deposited silver halide protrusions forming epitaxial junctions with the tabular grains, the protrusions (a) being located on up to 50 percent of the surface area of the tabular grains, (b) having a higher overall solubility than at least that portion of the tabular grains forming epitaxial junctions with the protrusions, and (c) forming a face centered cubic crystal lattice.

Abstract: An improved spectrally sensitized ultrathin tabular grain emulsion is disclosed in which tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide and at least 0.25 mole percent iodide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, (e) exhibiting an average thickness of less than 0.07 .mu.m, and (f) having latent image forming chemical sensitization sites on the surfaces of the tabular grains, are spectrally sensitized. The speed-granularity relationship of the emulsion is improved by employing in forming the surface chemical sensitization sites at least one silver salt epitaxially located on tabular grain surface sites that contain increased iodide concentrations.