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 method is disclosed of manufacturing radiation-sensitive emulsions by a pulsed flow double-jet process in which high chloride silver halide grains are grown in the presence of a thioether ripening agent in the dispersing medium in the reaction vessel the silver halide grains exhibiting an average grain roundness coefficient n in the range of from 2 to less than 15.

Abstract: A silver halide photographic material is disclosed, comprising a support having thereon at least one light-sensitive silver halide emulsion layer, wherein at least 80% of the entire projected area of the silver halide grains contained in said silver halide emulsion layer are occupied by tabular silver halide grains having an aspect ratio of 2 or more and main planes of {111} faces, said silver halide grains comprise at least 80 mol % of silver chloride, and said tabular silver halide grains are spectrally sensitized with the dye represented by formula (S); ##STR1## wherein Z.sub.1 and Z.sub.2 each represents a sulfur atom, a selenium atom, an oxygen atom or a nitrogen atom; and V.sub.1 and V.sub.2 each represents a monovalent substituent, provided that V.sub.1 and V.sub.2 each does not represent an aromatic group and adjacent two or more groups represented by V.sub.1 or V.sub.2 are not bonded to each other to form a condensed ring; I.sub.1 and I.sub.2 each represents 0, 1, 2, 3 or 4; L.sub.1, L.sub.2 and L.

Abstract: The preparation of finely-divided, homodisperse dispersions from a liquid medium having sparingly soluble particles contained therein, the particles being produced in a tubular reactor by the reaction of reactants dissolved in the medium, is carried out by introducing the solutions of the reactants, at least at the reaction temperature, into the tubular reactor separately from one another, as coaxial, laminar, parallel flows, and by shielding them from the reactor wall.

Abstract: A method is disclosed of manufacturing a radiation-sensitive tabular grain emulsion comprised of (a) providing in a stirred reaction vessel a host tabular grain emulsion containing greater than 50 mole percent bromide, based on silver, and a speed enhancing amount of iodide and (b) then introducing a silver salt solution into the stirred reaction vessel, wherein (1) the silver salt solution is introduced into the stirred reaction vessel at a rate sufficient to create a new grain population, (2) halting introduction of the silver salt solution for a time sufficient to allow the new grain population to be ripened out, and (3) repeating steps (1) and (2) from 3 to 20 times until silver introduced in steps (1) and (2) amounts to from 5 to 50 percent of total silver forming the radiation-sensitive tabular grain emulsion.

Abstract: A process of preparing a radiation-sensitive silver halide emulsion is disclosed in which a polyalkylene oxide block copolymer surfactant is employed. Dispersion of the polyalkylene oxide block copolymer surfactant in the aqueous dispersing medium is increased by the inclusion of an auxiliary surfactant. The auxiliary surfactants are selected from among those that, in the form of an aqueous solution containing 10 percent by weight of the auxiliary surfactant based on total weight of the aqueous solution, is miscible in all proportions with at least one of water and the polyalkylene oxide block copolymer surfactant.

Abstract: A method for producing a silver halide emulsion in which grains having an aspect ratio of from 1.5 to 100 occupy from 75 to 100% of the total projected area of all grains comprising at least nucleation, ripening and grain growth processes in a dispersion medium solution containing water and a dispersion medium, wherein the dispersion medium solution contains low molecular weight gelatin having a molecular weight of from 1,000 to 70,000 at least during a nucleation process and chemically modified gelatin having a chemical modification rate of the amino group of from 15% to 100% at least during a grain growth process.

Abstract: A photographic emulsion comprising dispersed in a binder sensitized silver halide grains wherein the emulsion is sensitized from an organometallic compound of formula:(R).sub.n (X).sub.m M (I)wherein M is a metal selected from the group consisting of lead, tin, boron, bismuth and thallium, each R is independently an alkyl group, a cycloalkyl group, an aryl group, a heterocyclic group, an alkenyl group or a alkynyl group, each X is independently halogen, hydroxy, or alkoxy, n is 1 to 4 and m is 0 to 3, with the proviso that when M is lead or tin, n is 1 to 4 and m+n is 4, when M is boron or bismuth, n is 1 to 3 and m+n is 3 and when M is thallium, either n is 1 and m is 0, or n is 1 to 3 and n+m is 3.

Abstract: A radiation-sensitive medical diagnostic film for soft tissue imaging, particularly mammography, is disclosed. The film allows more rapid processing than films currently available for mammographic imaging and maintains acceptably high levels of image sharpness and low levels of mottle. The radiographic film records medical diagnostic images of soft tissue through (a) exposure by a single intensifying screen located to receive an image bearing source of X-radiation and (b) processing, including development, fixing and drying, in 90 seconds or less comprised of a film support transparent to radiation emitted by the intensifying screen and having opposed front and back major faces and an image-forming portion for providing, when imagewise exposed by the intensifying screen and processed, an average contrast in the range of from 2.5 to 3.5, measured over a density above fog of from 0.25 to 2.0.

Abstract: The invention relates to a method of forming a silver halide emulsion comprising adding triiodide during grain formation or sensitization.

Abstract: A method has been found of preparing a silver halide emulsion comprising silver chlorobromoiodide or silver chloroiodide tabular grains with at least 75 mole % of chloride and from 0.1 up to 3 mole % of iodide, based on silver, further having {111} crystal faces, an average aspect ratio of at least 2:1, with at least 50%, more preferable at least 75% and still more preferable more than 90% of the total projected area of all grains being provided by said tabular grains and with a variation coefficient on sphere equivalent diameter (SED) of said grains being lower than 0.30, more preferably lower than 0.25 and most preferable from 0.05 up to at most 0.

Abstract: A process for reduction-sensitizing a silver halide photographic emulsion is disclosed, comprising reduction-sensitizing a silver halide basis grain having a silver bromide content of 75 mol % or more and thereafter or at the same time, depositing silver halide having a silver chloride content of 50 mol % or more on the surface of said basis grain not to have a distinct epitaxial form. Further disclosed is a silver halide photographic light-sensitive material containing a silver halide emulsion prepared by the process.

Abstract: A silver halide light sensitive photographic material is disclosed, comprising a support having thereon a red-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a blue-sensitive silver halide emulsion layer, wherein at least one of the red-sensitive, green-sensitive and blue-sensitive layers comprises a high-speed silver halide emulsion layer, a medium-speed silver halide emulsion layer and a low-speed silver halide emulsion layer, the low-speed layer contains a dye forming coupler having coupling reactivity higher than that of a coupler contained in the mdium speed layer.

Abstract: A photographic element is disclosed having at least one emulsion layer comprised of (a) radiation-sensitive silver halide grains, (b) sensitizer for the radiation-sensitive silver halide grains, (c) hydrophilic colloid vehicle, including peptizer for the radiation-sensitive silver halide grains, and (d) light scattering particles, wherein (a) the radiation-sensitive silver halide grains include tabular grains (1) having an aspect ratio of at least 2.0, (2) having {111} major faces, (3) containing greater than 50 mole percent bromide, based on silver, and (4) accounting for greater than 50 percent total grain projected area, (b) the sensitizer includes a fragmentable electron donating sensitizer, (c) the peptizer is a water dispersible cationic starch, and (d) the light scattering particles have aspect ratios of less than 1.5 and can be dissolved for removal from the emulsion layer. The photographic elements exhibit enhanced imaging speed and can be employed for color or black-and-white photographic imaging.

Abstract: A method for producing a light-sensitive silver halide photographic emulsion is disclosed, comprising (a) a step of forming silver halide grain nuclei containing twin grain nuclei in a dispersion medium solution, (b) a step of ripening said grain nuclei to preferentially remain tabular grain nuclei, and (c) a step of growing said tabular grain nuclei into tabular grains to form a tabular silver halide grain, wherein in step (a), a silver halide nucleus having a chloride content of 10 mol % or more based on the amount of silver contained in the nucleus is formed, and the tabular silver halide grain obtained through steps (a), (b) and (c) has a Br content of 50 mol % or more based on the total silver amount.

Abstract: A silver halide photographic material has at least one photosensitive silver halide emulsion layer and at least one non-photosensitive hydrophilic colloid layer on a support. The silver coverage per surface is 1.0-2.2 g/m.sup.2. The silver halide emulsion layer contains silver halide grains wherein tabular silver halide grains having an aspect ratio of at least 5 account for at least 50% of the entire projected area of silver halide grains. The silver halide grains have been grown on pure silver bromide or silver chlorobromide grains as nuclei so as to form silver iodobromide or silver chloroiodobromide having a silver iodide content of 0.1-3.20 mol % at the end of growth. This X-ray photosensitive material having high sensitivity and sharpness is used with a regular screen.

Abstract: A method has been described for preparing a gelatinous emulsion having grains rich in silver choride, wherein at least 70%, and more preferred 90%, of the total projected area of all grains is provided by {111} tabular grains having an average aspect ratio of more than 2:1, an average equivalent circular diameter of at least 0.3 .mu.m and an average thickness of from 0.05 to 0.25 .mu.

Abstract: A method is disclosed for washing silver halide photographic emulsions, including desalting and/or concentrating, based on depletion phase separation mechanism, wherein phase separation is effected by the addition of water-soluble non-interactive and non-adsorbing carboxyl polymers. The process involves the separation of the supernatant fluid, containing the undesirable water soluble salts and the added phase separating agents, from the washed and condensed silver halide phase for desalting and redispersion of the latter.

Abstract: A method for producing a photographic silver halide emulsion containing silver halide grains having a silver chloride content of 50 mol % or more and at least 30% of the surface area of the grains comprising [111] faces is disclosed, wherein the silver halide grains are formed in the presence of at least one kind of compounds represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group, an alkenyl group, or an aralkyl group; R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 each represents a hydrogen atom or a group capable of substituting for the hydrogen atom, R.sub.2 and R.sub.3, R.sub.3 and R.sub.4, R.sub.4 and R.sub.5, and R.sub.5 and R.sub.6 each may be ring-condensed, provided that at least one of R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 represents an aryl group; and X.sup.- represents a counter anion.

Abstract: A method is disclosed for washing silver halide photographic emulsions, including desalting and/or concentrating, based on depletion phase separation mechanism, wherein phase separation is effected by the addition of water-soluble non-interactive and non-adsorbing non-ionic polymers or non-ionic surfactant micelles. The process involves the separation of the supernatant fluid, containing the undesirable water-soluble salts and the added phase separating agents, from the washed and condensed silver halide phase and redispersion of the latter.

Abstract: A light-sensitive silver halide photographic material and a method for preparing said material is provided, wherein said material comprises a support and on one or both sides thereof at least one silver halide emulsion layer and a protective antistress layer as an outermost layer, characterized in that said silver halide emulsion layer(s) and/or said protective antistress layer comprise(s) at least one zeolite loaded with a photographically useful group. Said photographically useful group is a soluble salt, an organic compound releasing chloride, bromide or iodide, a sulfur salt, a selenium salt, a tellurium salt and/or a metal salt of group VIII.

Abstract: A process for producing tabular silver halide grains in a dispersion medium solution, wherein the dispersion medium comprises a gelatin derivative containing at least two carboxyl groups (--COOH) which are newly introduced through chemical modification of amino groups (--NH.sub.2) of gelatin molecule, thereby monodisperse tabular silver halide grains small in thickness and large in aspect ratio are provided.

Abstract: A silver halide photographic emulsion is disclosed, comprising silver halide tabular grains having integrated therein dislocation lines and having an aspect ratio of 1.5 or more and a circle-corresponding diameter of 0.6 .mu.m or less, wherein the grains having integrated therein dislocation lines from the site determined by the following expression (I) occupy 50% or more of the total projected area:D=(1.4S.sup.1.5).times.100.+-.15 (I)wherein D represents a ratio (%) of silver amount consumed until the integration of the dislocation lines to the total amount of silver used and S represents a sphere-corresponding diameter (.mu.m) of a final grain, provided that D is 5 or more.

Abstract: A photosensitive element is disclosed comprising on at least one side of a support one or more silver halide emulsion layers and a non-light sensitive hydrophilic colloidal layer characterized in that at least one emulsion layer comprises silver halide crystals having an oligomeric platinum complex containing only carbonyl ligands, which is represented by formula (1):[Pt.sub.3 (CO).sub.6 ].sub.n.sup.2- (1)wherein n is not more than 10.The invention also provides a method for the preparation of a photosensitive element as described hereinbefore comprising the step of introducing the oligomeric platinum carbonyl containing complex as represented by formula (1) during grain formation in at least one silver halide emulsion.

Abstract: A method for producing a silver halide emulsion is disclosed, which comprises:supplying a water-soluble silver salt aqueous solution and a water-soluble halide aqueous solution from solution-feeling ports provided in a closed type stirring tank of a mixing vessel,controlling the stirring condition of the mixture of aqueous solutions supplied by rotation-driving at least one pair of stirring blades having no rotary shaft protruding the wall of the stirring tank, which are disposed in said stirring tank;discharging silver halide fine grains which are formed with the completion of the stirring process from a solution-discharging port provided in a closed type stirring tank; andsupplying said silver halide fine grains to a reaction vessel where nucleation and/or grain growth of silver halide grains are conducted, and further a silver halide photographic emulsion comprising a dispersion medium and silver halide grains produced by the above method is disclosed.

Abstract: A process of washing an emulsion such as a silver halide emulsion which contains a hydrophilic colloid comprises deionizing the emulsion and coagulating the emulsion with an anionic polymer and separating the coagulum from the supernatant and resuspending the coagulum with hydrophilic colloid, water and a base.

Abstract: A process of preparing a radiation-sensitive silver halide emulsion is disclosed in which the silver halide grains form dispersed clumps. A population of fine silver halide grains is precipitated at higher concentrations than previously taught for preparing this type of an emulsion by employing a peptizer limited in amount, limited in methionine content, or both. Following formation of the grains, they are aggregated into clumps by the addition of a surfactant, optionally assisted by the adding iodide, increasing pH or both. The grain clumps are stabilized against further aggregation by adding a high methionine peptizer and optionally assisted by the precipitation of additional silver halide.

Abstract: There is disclosed a silver halide photographic emulsion, which comprises silver halide tabular grains that have {100} planes as principal planes and have the following features, the emulsion being subjected to chemical sensitization: (a) 50% or more of the projected areas of the tabular grains is attributed to tabular grains having an aspect ratio of 2 or more, (b) each of the tabular grains has a mixed crystal region containing, in addition to main halide ions, different halide ions in an amount of 0.01 mol % or more, but 25 mol % or less, in the nucleus part and/or in part of the growth part or in the whole of the grown part, and (c) when the principal planes of the tabular grains are observed using a transmission-type electron microscope, one or more, but ten or less, dislocation lines are observed on the principal planes of each grain of 50% or more of the tabular grains.

Abstract: The present invention relates to a method for manufacturing a silver halide photographic emulsion comprising a nucleation step, a growing step and a washing step, wherein a reduction sensitization is performed between said growing step and said washing step in the presence of a sulfuring agent and a stabilizer. According to a preferred embodiment a fine grain silver halide emulsion is added either between the addition of stabilizer and the addition of sulfuring agent or between the addition of sulfuring agent and the start of reduction sensitization or both.

Abstract: A method for producing a silver halide photographic emulsion, a method for producing thereof, and a light-sensitive material using the same, the method comprising the steps of: (a) producing a host emulsion comprising silver bromide or silver iodobromide tabular grains having an average silver iodide content (I.sub.1 mol %) of the entire silver halide grains of 5 mol % or less, in which 60% or more of the projected area of the entire silver halide grains accounting for tabular grains having an aspect ratio of 3.0 or more; (b) dissolving a periphery of the tabular grains completely with an iodide ion being added to the host emulsion; and then (c) producing final tabular grains by reclaiming a periphery containing silver iodobromide from the region containing the periphery having been completely dissolved.

Abstract: A photographic element comprises a support bearing two or more silver halide emulsion image-forming layers each containing ultrathin tabular grains or a support bearing at least three image-forming layers for forming images of different color in which at least one of the layers contains ultrathin tabular grains, wherein the imaging silver contained in the total of all the image-forming layers of the element is as described in subparts (1), (2) and (3):(1) ultrathin tabular grains, having a thickness of less than 0.07 microns, comprise at least 25 wt % of the total imaging silver content of subparts (1), (2), and (3);(2) (a) tabular grains of thickness at least 0.10 microns and (b) non-tabular grains having an ECD of at least 0.15 microns and less than 0.70 microns, comprise not more than 50 wt % of the total imaging silver content of subparts (1), (2), and (3); and(3) tabular grains having a thickness of at least 0.07 microns and a thickness less than 0.

Abstract: A silver iodide fine grain emulsion comprising a dispersion medium and fine grains of silver iodide has an average grain size of 0.02 to 0.07 .mu.m, contains 0.6 mol or more of silver iodide per liter thereof in a dissolved state at 40.degree. C., and has an electric conductivity of 4,500 to 15,000 .mu.S/cm in a dissolved state at 40.degree. C. A lightsensitive silver halide emulsion produced by using the above silver iodide fine grain emulsion is also disclosed. A silver halide photographic lightsensitive material comprising a support and, superimposed thereon, at least one lightsensitive silver halide emulsion layer in which the above lightsensitive silver halide emulsion is contained, is also disclosed.

Abstract: The production of a silver halide emulsion in an aqueous protective colloid solution by the reaction of, on the one hand, silver nitrate, and, on the other, at least one water-soluble halide, may be performed particularly simply and with great apportioning accuracy, if, during at least part of the precipitation, at least the predominant part of one reactant is added in the form of a solid salt to the aqueous protective colloid solution.

Abstract: A silver halide photographic material comprising a support having thereon at least one silver halide emulsion layer containing silver halide grains having a silver chloride content of at least 70 mol % and containing a transition metal selected from the group consisting of elements belonging to Groups V to VIII of the Periodic Table in an amount of at least 1.times.10.sup.-7 mol per mol of silver, the silver halide grains being formed in the presence of a compound represented by following formula (I); ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4, which may be the same or different, each represents a hydrogen atom, an alkyl group, an aryl group, an amino group, a hydroxy group, an alkoxy group, an alkylthio group, a carbamoyl group, a halogen atom, a cyano group, a carboxy group, an alkoxycarbonyl group, or a heterocyclic residue; and R.sup.1 and R.sup.2 or R.sup.2 and R.sup.3 may combine with each other and form a 5-membered or 6-membered ring; and with the proviso that at least one of R.sup.

Abstract: The invention relates to an emulsion comprising sharp cornered silver chloride grains, said grains having a rounding index less than 0.3 and dithiolone dioxide.

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: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a Au(I) compound having the formula wherein Z is a substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic groups, or one or both of R.sub.1 and R.sub.2 or R.sub.3 and R.sub.4, may independently combine to form a nitrogen containing ring with the nitrogen to which they are attached.

Abstract: A radiation-sensitive silver halide emulsion is disclosed comprised of composite grains including host grains having predominantly {111} crystal faces, cuprous ions adsorbed to the {111} crystal faces of the host grains to act as a site director for subsequently deposited silver salt, and silver salt protrusions having their highest incidence adjacent at least one of the corners and edges of the host grains.

Abstract: A silver halide emulsion comprising at least a dispersion medium and silver halide grains is disclosed, wherein the silver halide grains comprise tabular grains having, as the main planes, {100} planes and having an aspect ratio (diameter/thickness) of 1.5 or more, in a proportion of 10% or more of the sum of the projected areas of all the grains, and the tabular grains each has at least one discontinuous halogen composition gap plane in their central part in such a way that the gap involves at least a difference of from 10 to 100 mol % in terms of the Cl.sup.- content or the Br.sup.- content or a difference of from 5 to 100 mol % in terms of the I.sup.- content between the adjacent layers. The reproducibility of the emulsion is good. The emulsion has high sensitivity, good graininess and good ability of forming high-quality photographic images.

Abstract: A silver halide photographic emulsion is disclosed, comprising a support having thereon at least one silver halide emulsion layer, wherein the silver halide grain contained in the silver halide emulsion layer has a silver chloride content of 50 mol % or more, 30% or more of the surface area of the grain comprises a (111) face, and the silver halide grain is formed in the presence of at least one compound represented by formula (I) and contains a hexacyano complex represented by formula (II) such that the outermost layer of the grain has a hexacyano complex concentration of at least 1.times.10.sup.-4 mol/mol-Ag.

Abstract: Disclosed is a method of manufacturing a silver halide emulsion, the method comprising the step of ultrafiltrating and electrodialyzing a silver halide emulsion containing silver halide grains and gelatin having an average molecular weight of 500 to 70,000, by means of an ultrafiltration unit having an ultrafiltration membrane, whereby the emulsion is desalted and concentrated.

Abstract: A method for producing a silver halide photographic emulsion is described, which emulsion comprises tabular grains of silver bromide or silver iodobromide having {111} faces as major faces parallel to each other, wherein an aqueous solution of silver salt or an aqueous solution of silver salt and an aqueous solution of halide is/are added at least one time within the period of time after the first nucleation and before Ostwald ripening progresses.

Abstract: A silver halide photographic emulsion comprise silver chlorobromide or silver iodobromochloride grains, each grain having a silver chloride region in an amount of 0.3 to 50 mol % based on the total silver amount of the grain, and each grain containing at least one ion selected from the group consisting of ions of Ga, In and Group 8, Group 9 and Group 10 metals. A silver halide photographic emulsion that is occupied by tabular grains having an equivalent circular diameter of 0.1 to 0.6 .mu.m in an amount of at least 70% in number, wherein each of the tabular grains has a multilayer structure comprising at least two layers, and at least one of the layers contains chloride in an amount of 0.

Abstract: A silver halide photographic element comprising a silver halide emulsion which is greater than 50 mole % silver chloride, said emulsion being in reactive association with a dithiolone 1-oxide compound represented by the following formula: ##STR1## wherein b is C(O), C(S), C(Se), CH.sub.2 or (CH.sub.2).sub.2, and R.sup.1 and R.sup.2 are independently H, or aliphatic, aromatic or heterocyclic groups, alkoxy groups, hydroxy groups, halogen atoms, aryloxy groups, alkylthio groups, arylthio groups, acyl groups, sulfonyl groups, acyloxy groups, carboxyl groups, cyano groups, sulfo groups, or amino groups, or R.sup.1 and R.sup.2 together represent the atoms necessary to form a five or six-membered ring or a multiple ring system; and a sulfinate compound.

Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a Au(I) compound having the formula ##STR1## wherein Z is a substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic groups, or one or both of R.sub.1 and R.sub.2 or R.sub.3 and R.sub.4, may independently combine to form a nitrogen containing ring with the nitrogen to which they are attached.

Abstract: A photographic element comprising a support having situated thereon a silver halide emulsion layer, said emulsion layer comprising a compound of the formula:Z--S--Au(I)--S--Q (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andQ represents a heterocyclic group wherein S and Q together represent a mesoionic group.

Abstract: A high chloride {100} tabular grain emulsion is prepared by creating grain nuclei containing greater than 45 mole percent bromide. Growth onto the grains under conditions favorable for high chloride {100} grain growth is conducted while maintaining (a) a temperature in the range of from 25 to 85.degree. C., (b) a pH in the range of from 3.5 to 8.5, and (c) a vAg in the range of from 120 to 200 mV. Crystal lattice field distortions are observed at the nucleation site, and the nucleation site exhibits the maximum bromide concentration, which is greater than 5 mole percent, based on silver at the site.

Abstract: A process of preparing a photographically useful high chloride {100} tabular grain emulsion is disclosed that, following grain nucleation, introduces the total silver required for grain growth before undertaking ripening at a temperature of from 60 to 95.degree. C. The advantages attainable include a higher concentration of the silver in the final emulsion and high chloride tabular grains having larger mean grain sizes and higher average aspect ratios and accounting for a higher percentage of total grain projected area.

Abstract: A process of preparing a photographically useful high chloride {100} tabular grain emulsion is disclosed. The grain characteristics of the emulsion are improved by interrupting precipitation of the grain nuclei used to prepare the emulsion by performing a halide conversion step in which a molar ratio of iodide ion to bromide ion in the range of from 1.times.10.sup.-4 :1 to 5.times.10.sup.-2 :1 is employed.

Abstract: A silver halide emulsion is disclosed, comprising at least a dispersion medium and silver halide grains, wherein at least 30% of the entire projected area of the silver halide grains is occupied by tabular grains having {100} faces as major faces, an aspect ratio (diameter/thickness) of from 1.5 to 30 and a Br content of from 30 to 70 mol %, and the coefficient of variation of the halogen composition distribution among the silver halide grains is 10% or less. Further disclosed is a method for producing the silver halide emulsion.