Abstract: A silver halide photographic material is disclosed, comprising a support having thereon at least one silver halide emulsion layer and the other hydrophilic colloid layer, wherein the emulsion layer comprises a silver halide emulsion containing a compound having a nitrosyl ligand or a thionitrosyl ligand per mol of silver and a transition metal selected from the group consisting of the elements belonging to Groups V to X of the periodic table in an amount of 1.times.10.sup.-6 mol or more per mol of silver, and at least one of the silver halide emulsion layer and the other hydrophilic colloid layer contains at least one compound represented by formula (I), (II), (III), (IV) or (V). ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.

Abstract: A silver halide photographic material comprises a silver halide emulsion layer provided on a support. In the photographic material of the present invention, the silver halide emulsion is sensitized with a new tellurium sensitizer. The tellurium sensitizer is represented by the formula (I) or (II): ##STR1## in which each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently is an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, a heterocyclic group or an acyl group; at least two of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are combined with each other to form a heterocyclic ring; R.sup.5 is an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group or a heterocyclic group; R.sup.6 is --NR.sup.7 R.sup.8, --NR.sup.9 --NR.sup.10 R.sup.11 or --OR.sup.12 ; R.sup.5 and R.sup.6 may be combined with each other to form a heterocyclic ring; each of R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11 and R.sup.

Abstract: A silver halide photographic material having at least one light-sensitive emulsion layer on a support, wherein at least one light-sensitive emulsion layer has an emulsion containing silver halide grains of silver chlorobromide, silver chloroiodide, silver chloroiodobromide or silver chloride having a silver chloride content of 90 mol % or more, and incorporated with the silver halide grains are an iron compound of from 10.sup.-7 to 10.sup.-3 mol per mol of silver halide, and a tellurium compound of from 10.sup.-7 to 10.sup.-4 mol per mol of silver halide, before completion of physical ripening of the grains. The photographic material of the present invention is exposed for a short time period of 10.sup.-3 second or less and then color-developed to form a photographic image. The material has high sensitivity and high contrast and has excellent rapid processability.

Abstract: A photographic emulsion is disclosed in which a spectral sensitizing dye is adsorbed to the surface of octahedral silver bromide grains optionally containing iodide. The grains each contain a buried shell formed in the presence of a hexacoordination complex of iron and at least three cyanide ligands.

Abstract: A silver halide photographic material comprises a silver halide emulsion layer provided on a support. In the photographic material of the present invention, the silver halide emulsion layer contains a compound represented by the formula (I): ##STR1## in which each of R.sup.1, R.sup.2 and R.sup.3 independently is a group of chain structure selected from an alkyl group, an alkenyl group, an alkynyl group and an alkylthio group, each of which may have one or more substituent groups; and the number of the carbon atoms contained in the compound represented by the formula (I) is 3 to 12. A process for sulfur sensitization of a silver halide emulsion using the compound represented by the formula (I) is also disclosed.

Abstract: A method for the production of a silver image with improved contrast by the development of an image-wise exposed photographic silver halide emulsion layer material with a developer liquid containing a hydroquinone in the presence of an auxiliary developing agent, wherein said developer liquid is applied to said photographic material containing silver halide grains that have been chemically sensitized with organic thiosulphonic acid anions in combination with a gold sensitizer in the absence of thiosulphate ions.

Abstract: A photographic emulsion is disclosed in which an infrared spectral sensitizing dye is adsorbed to the surface of silver bromide grains optionally containing iodide. The grains are formed in the presence of a hexacoordination complex of iron and at least three cyanide ligands to counteract dye desensitization.

Abstract: A light-sensitive silver halide photographic material that can give an improved blackness of the silver-formed image by the development, having a high sensitivity with a high covering power, is disclosed. The material comprises a silver halide emulsion layer containing silver halide tabular grains which have an aspect ratio of not less than 3, covering not less than 50% of the total sum of projected areas, and the layer comprises a compound represented formula I, ##STR1## wherein Rs and Ms represent as specified in the claims.

Abstract: A method of manufacturing a silver halide emulsion, wherein reduction sensitization is performed by using at least one of ascorbic acid and derivatives thereof in a process of manufacturing a silver halide emulsion. The invention is further directed to a of manufacturing a silver halide emulsion, wherein reduction sensitization is performed by using at least one of ascorbic acid and derivatives thereof during precipitation of silver halide grains.

Abstract: A photochromic composition for incorporation into a light-transmitting polymer is described. Silver halide crystallites are capped with an organic capping group using multivalent metal ions integrated into the surface of the silver halide crystallite to provide crystallite surface sites that provide a handle between the organic capping group and the silver halide crystallites. The size of the capped silver halide crystallites are less than about 1000 .ANG.. A reverse micelle technique is used to control the size of the silver halide crystallite while integrating the multivalent ions and bonding the organic capping group. The capped crystallites are soluble in organic solvents and, as such, are readily incorporated into a polymer matrix.

Abstract: This invention provides gold(I) complexes comprising sulfur- and selenium-substituted macrocyclic polyether ligands, photographic elements containing the compounds, and emulsions containing the compounds. The compounds include monomers and dimers having the following formulas, respectively:[AuL].sup.+ X.sup.- or [AuL].sub.2.sup.2+ 2X.sup.-wherein X.sup.- is any suitable anion such as tetrafluoroborate, nitrate, etc., and wherein L is a macrocyclic ligand containing at least two thioether and/or selenoether linkages and comprising from about 12 to about 30 members in the ring. The general structural formula for the macrocyclic compounds L may be represented as follows: ##STR1## wherein Q.sub.1 and Q.sub.2 are each independently sulfur or selenium, and R.sub.1 and R.sub.

Abstract: A silver halide photographic emulsion contains chemically sensitized silver halide grains each of which has at least one structure resulting from the difference in halogen compositions. The grains have been prepared in the presence of an oxidizing agent for silver. A silver halide photographic light-sensitive material has at least one layer of the silver halide emulsion on a support.

Abstract: A silver halide photographic material composed of a support having thereon at least one silver halide emulsion layer containing substantially normal silver halide grains having a (111) plane and a (100) plane and capable of preferentially forming a latent image on the (100) plane; the (111) plane occupying at least about 40% of the surface of the grains or the (100) plane occupying more than about 60% of the surface of the grains; provided that when the (111) plane occupies at least about 40% of the surface of the grains, the grains are spectrally sensitized with (a) at least one spectral sensitizing dye selectively adsorbed more on the (100) plane than on the (111) plane, or (b) at least one spectral sensitizing dye selectively adsorbed more on the (111) plane than on the (100) plane.

Abstract: In a silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support, light-sensitive silver halide grains contained in the silver halide emulsion layer have been subjected to selenium sensitization, and the silver halide emulsion layer or another hydrophilic colloid layer which is in a water-permeable relationship with the silver halide emulsion layer contains at least one compound represented by formula (I) (wherein Z represents a heterocyclic ring directly or indirectly having at least one substituent group selected from the group consisting of --SO.sub.3 M, --COOR.sub.1, --OH, and --NHR.sub.2, M represents hydrogen, alkali metal, quaternary ammonium, or quaternary phosphonium, R.sub.1 represents hydrogen, alkali metal, or alkyl having 1 to 6 carbon atoms, R.sub.2 represents hydrogen, alkyl having 1 to 6 carbon atoms, --COR.sub.3, --COOR.sub.3, or --SO.sub.2 R.sub.3, and R.sub.

Abstract: This invention describes the use of a selenium sensitizer on a large grain size silver chloride emulsion. The process of the invention provides a large and unexpected speed increase on silver chloride emulsion crystals greater than about 0.4 micron in edge length. A photosensitive emulsion according to the invention is particularly useful as a yellow layer in a color print film.

Abstract: Silver halide photographic elements which are capable of high-contrast development and are especially useful in the field of graphic arts comprise surface latent image forming high-chloride silver halide grains and have incorporated therein a hydrazine compound which functions as a nucleator, an amino compound which functions as an incorporated booster, and a benzimidazolocarbocyanine sensitizing dye that provides enhanced photographic sensitivity yet leaves substantially no sensitizing dye stain after rapid access processing.

Abstract: A silver halide photographic material low in fogging generation and high in sensitivity comprising a silver halide emulsion selenium sensitized with at least one compound selected from the group consisting of compounds represented by general formulae (I) and (III): ##STR1## wherein each of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represents an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, a heterocyclic group, an acyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group or a sulfamoyl group, provided that a tetramethylselenourea is excluded; ##STR2## wherein each of R.sub.8, R.sub.9, R.sub.10 and R.sub.

Abstract: There is disclosed a silver halide photographic material which is sensitized with a novel selenium sensitizer. It provides less fog and markedly little sensitivity degradation during storage under a high temperature and humidity conditions, while providing the same level of a sensitivity. The silver halide photographic material contains at least one compound represented by the following Formula (I): ##STR1## Wherein R.sub.1 represents a substituted phenyl or condensed aryl group, an aliphatic group, a heterocyclic group, OR.sub.4, --NR.sub.5 (R.sub.6), SR.sub.7, SeR.sub.8, X.sub.1, or a hydrogen atom; R.sub.2 and R.sub.3 each represents an aliphatic group, an aromatic group, a heterocyclic group, OR.sub.9, --NR.sub.10 (R.sub.11), SR.sub.12, SeR.sub.13, X.sub.2, or a hydrogen atom; R.sub.5, R.sub.6, R.sub.10 and R.sub.11 each represents an aliphatic group, an aromatic group, a heterocyclic group, or a hydrogen atom; R.sub.4, R.sub.7, R.sub.8, R.sub.9, R.sub.12 and R.sub.

Abstract: Silver halide photographic elements which are capable of high contrast development and are especially useful in the field of graphic arts have incorporated therein a hydrazine compound which functions as a nucleator, an amino compound which functions as an incorporated booster, and a thioether compound which functions to inhibit pepper fog and restrain image spread.

Abstract: UV sensitive direct positive silver halide photographic material for duplicating processes which can be safely handled under roomlight conditions, said material comprising a support having thereon at least one silver halide emulsion layer comprising a prefogged direct positive silver halide emulsion, preferably one having a chloride content of at least 70 mole % and comprising internal electron traps, said emulsion layer or a hydrophilic colloid layer in water-permeable relationship to said emulsion layer containing at least one nitro-substitued indazole or benzimidazole derivative and at least one non-nitro-substituted indazole or benzimidazole derivative.

Abstract: A silver halide color photographic light-sensitive material is disclosed. The light-sensitive material comprises a support having thereon a silver halide emulsion layer containing silver halide grains each containing an iridium compound and a compound containing iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium or platinum; elemental sulfur; and two kinds of specified monomethine cyanine sensitizing dyes. The light sensitive material is improved in the reciprocity law failure property and the sensitivity fluctuation due to variation of atmosphere humidity.

Abstract: A process of forming superhigh-contrast negative images is disclosed. The process comprises the steps of imagewise exposing a substantially surface latent image-type silver halide photographic material which is spectrally sensitized with a sensitizing dye and then developing said photographic material with a developer, wherein said photographic material contains a heterocyclic thione compound and said developer comprises (a) an aminophenol derivative developing agent, (b) a reductone compound, (c) a quaternary ammonium salt, and (d) a compound represented by formula (I): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3, which may be the same or different, each represents a hydrogen atom, a nitro group, a halogen atom, or a cyano group, and wherein said development processing is carried out in the existence of at least one kind of a polyalkylene oxide or a derivative thereof. The process provides negative images of superhigh contrast having gamma over 10 substantially free from appearance of pepper.

Abstract: A silver halide color photographic material comprising a support having thereon one or more layers having a surface pH of 5.0 to 6.5, including at least one silver halide emulsion layer containing a gold-sensitized silver halide emulsion having a silver chloride content of at least 90 mol % and a coupler represented by formula (I): ##STR1## wherein R.sub.1 represents an aryl group or a tertiary alkyl group; R.sub.2 represents fluorine, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a dialkylamino group, an alkylthio group or an arylthio group; R.sub.3 is a group which is substituted for a hydrogen atom on the benzene ring; X represents hydrogen or a group capable of being cleaved upon a coupling reaction with an oxidation product of an aromatic primary amine developing agent; and l is 0 or an integer from 1 to 4.

Abstract: A silver halide photographic light-sensitive material of this invention is a silver halide photographic light-sensitive material having at least one silver halide emulsion layer on a support, wherein at least one of the silver halide emulsion layers contain at least one compound represented by formula (I): formula (I) ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 each represent an aliphatic group, an aromatic group, a heterocyclic group, OR.sub.4, NR.sub.5 (R.sub.6), SR.sub.7, OSiR.sub.8 (R.sub.9)(R.sub.10), TeR.sub.11, X, or a hydrogen atom, R.sub.4, R.sub.7, and R.sub.11 each represent an aliphatic group, an aromatic group, a heterocyclic group, a hydrogen atom, or a cation, R.sub.5 and R.sub.6 each represent an aliphatic group, an aromatic group, a heterocyclic group, or a hydrogen atom, R.sub.8, R.sub.9, and R.sub.10 each represent an aliphatic group, and X represents a halogen atom.

Abstract: Silver halide photographic elements which are capable of high-contrast development and are especially useful in the field of graphic arts comprise surface latent image forming high-chloride silver halide grains and have incorporated therein a hydrazine compound which functions as a nucleator, an amino compound which functions as an incorporated booster, and a combination of a gold compound and a thiourea compound which functions as a chemical sensitizer. Thiourea compounds effective for this purpose are substituted thioureas having one or two acyl substituents or having three alkyl substituents or having one aryl substituent and two alkyl substituents.

Abstract: Silver halide photographic elements which are capable of high-contrast development and are especially useful in the field of graphic arts comprise surface latent image forming high-chloride silver halide grains and have incorporated therein a hydrazine compound which functions as a nucleator, an amino compound which functions as an incorporated booster, and a combination of a gold compound and a urea compound which functions as a chemical sensitizer. Urea compounds effective for this purpose are 1,1,3,3-tetra-substituted middle chalcogen urea compounds in which at least one substituent comprises a nucleophilic center.

Abstract: The improved color photographic material has on a support at least one blue-sensitive silver halide emulsion layer, at least one green-sensitive silver halide emulsion layer and at least one red-sensitive silver halide emulsion layer, each of those emulsion layers having a specified spectral response. This color photographic material has high chroma and insures faithful reproduction of color hues even under illumination with a fluorescent lamp.

Abstract: A new class of electron-accepting compounds for photographic emulsions is disclosed represented by following general formula (I): ##STR1## wherein: each of Z and Q which may be the same or different represents the atoms necessary to complete an unsubstituted or substituted nitrogen-containing heterocyclic ring;each of T.sub.1 and T.sub.2 which may be the same or different represents alkyl, cycloalkyl, alkoxy, aryl, aryloxy, halogen, cyano, hydroxy, carboxyl, sulfo, carbamoyl, acyl, acylamino, sulfamoyl, sulfonamido or a benzocondensed ring, each of which can be further substituted or not;q=1, 2 or 3, and p and r=0, 1 or 2.In this formula the nitro containing heterocyclic nucleus is preferably nitropyridine or nitrothiazole.In a preferred embodiment of the invention electron-accepting compounds are incorporated in negative or direct positive roomlight emulsions. In the latter case the emulsion layer preferably contains in addition a nitroindazole or nitrobenzimidazole derivative.

Abstract: A method for preparing a silver halide emulsion containing silver halide grains comprising(i) preparing a mixture by mixing a compound represented by the following Formula (1) or (2), and a gold compound; and(ii) performing chemical ripening of the emulsion by adding said mixture thereto: ##STR1## wherein M, R, V and W independently represent a hydrogen atom or a substituent group; V and W may combine with each other to form a ring.

Abstract: A silver halide photographic material which comprises a support having provided thereon at least one light-sensitive emulsion layer, and which contains in said emulsion layer, or at least one other layer, at least one hydrazine derivative, at least one contrast enhancing agent and at least one redox compound capable of releasing a development inhibitor upon being oxidized. The hydrazine derivative is exemplified by compounds represented by the following formula: ##STR1## wherein R.sub.1 represents an aliphatic group or an aromatic group; R.sub.2 represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an amino group, a carbamoyl group or an oxycarbonyl group; G.sub.1 represents a carbonyl group, a sulfonyl group, a sulfoxy group, ##STR2## or an iminomethylene group; and A.sub.1 and A.sub.2 both represent a hydrogen atom, or, alternatively, one of them represents a hydrogen atom and the other represents an alkylsulfonyl group, an arylsulfonyl group, or an acyl group.

Abstract: A method for development processing of a light-sensitive silver halide photographic material comprising a support having provided thereon at least one surface latent image type silver halide emusion layer, in the presence of a compound represented by formula (I) ##STR1## wherein Q, X, A, B, M, m and n are as defined above. The method prevents generation of developer fog without reducing sensitivity.

Abstract: A light-sensitive silver halide photographic material comprising a support and provided thereon at least one silver halide emulsion layer containing a pyrazolo azole magenta dye-forming coupler represented by general formula M-I; ##STR1## (wherein Z represents a group of non-metallic atoms necessary to complete a nitrogen-containing heterocyclic ring which may have a substituent; X represents a hydrogen atom or a substituent capable of being split off upon reaction with an oxidation product of a color developing agent; and R represents a hydrogen atom or a substituent), to said silver halide emulsion layer an elementary sulfur having been added at an arbitrary timing before the formation of said silver halide emulsion layer on said support.

Abstract: Substituted diaminedithio-containing compounds useful for improving the speed of a silver halide emulsion are described. These compounds can be added in small amounts to the emulsion preferably after the emulsion has been chemically sensitized and just prior to coating. Fog levels are not greatly affected which is surprising since conventional sensitizers generally do increase the fog level.

Abstract: A silver halide light-sensitive material comprising a support having thereon at least one negative silver halide emulsion layer is disclosed, in which a coating weight of the total binder on one side of the support is not more than 4.2 g/m.sup.2 and silver halide grains in the emulsion layer have been subjected to reduction sensitization. The light-sensitive material has improved pressure resistance while exhibiting high sensitivity and suitability for ultra-rapid processing.

Abstract: A silver halide photographic material comprising a support having thereon at least one sensitive silver halide emulsion layer, wherein said emulsion layer comprises a monodisperse emulsion and said emulsion layer or other hydrophilic colloid layer contains at least one hydrazine derivative and at least one redox compound capable of releasing a development inhibitor when oxidized.

Abstract: A silver halide color photographic material comprising a support having thereon at least three silver halide emulsion layers which have different color sensitivities from each other, wherein at least one of the silver halide emulsion layers contains at least one magenta coupler represented by general formula (I) shown below, at least one of the silver halide emulsion layers contains at least one compound represented by general formula (II) shown below, at least one of the silver halide emulsion layers contains at least one compound represented by general formula (III) shown below and the pH of the layers of the silver halide color photographic material is from 5.0 to 6.5: ##STR1## wherein R.sup.1, X, Za, Zb, Zc, Q, M, Z, R.sub.4, R.sub.5, V.sub.1, V.sub.2, V.sub.3, V.sub.4, V.sub.5, V.sub.6, B.sub.7, V.sub.8, and X.sub.n are defined in the specification.

Abstract: Disclosed is a direct positive photographic material comprising a support having thereon at least one photographic emulsion layer containing previously non-fogged internal latent image-type silver halide grains, wherein the photographic emulsion layer contains at least one compound of formulae (I), (II) and (III) preferably along with at least one compound of formulae (IV), (V) and (VI), and that the internal latent image-type silver halide grains are silver bromide, silver chloride, silver iodobromide, silver chlorobromide or silver chloroiodobromide grains and contain at least one metal of manganese, copper, zinc, cadmium, rhenium, lead, bismuth, indium, thallium, zirconium, lanthanum, chromium, mercury and metals of Group VIII of the Periodic Table.M.sub.2 SO.sub.3 (I)MHSO.sub.3 (II)M.sub.2 S.sub.2 O.sub.5 (III)wherein M represents a hydrogen atom or a cation.R--SO.sub.2 S--M.sup.1 (IV)R--SO.sub.2 S--R.sup.1 (V)R--SO.sub.2 S--L.sub.m --S.O.sub.2 S--R.sup.2 (VI)wherein R, R.sup.1 and R.sup.

Abstract: The invention relates to a novel process for the chemical sensitization of silver halide photographic emulsions.The process according to the invention comprises adding as additional sensitizing agents a 40-260 .mu. moles/mole of a cyclic polyether containing 1 nitrogen and 5 oxygen atoms, or 2 nitrogen and 4 oxygen atoms, or 3 nitrogen and 3 oxygen atoms, or 4 nitrogen and 2 oxygen atoms as well as 12 carbon atoms and/or their complexes formed with gold and/or palladium and optionally 40-260 .mu. moles/mole of silver halide) of gold (I) or gold (III) sulfide to the sulfur-sensitized emulsion, and employing the cyclic polyether in relation to the noble metal salt in a molar ratio of 0.5:1-5:1 for the complex formation.

Abstract: A method for controlling pressure-induced fog in a silver bromide photographic material involves surface treatment of the emulsion AgBr grains with thiocyanate and an iodide salt. In particular, a process for making a pressure fog-resistant photographic emulsion includes steps of forming a photographic emulsion containing cubic or cubooctahedral silver bromide grains, surface-treating the AgBr grains with a thiocyanate by adding the thiocyanate to the emulsion, chemically sensitizing the emulsion, maintaining the emulsion at a temperature and for a time sufficient to allow the thiocyanate to react with the grain surfaces, and then surface-treating the AgBr grains with an iodide salt by adding the salt to the emulsion in an amount and under conditions effective to fill in cubic faces of the AgBr grains. The latter step partially or fully converts the AgBr grains to octahedral grains. A photographic element can then be made by coating the emulsion on a suitable base.

Abstract: An aqueous silver sulfide sol is prepared which has an absorption spectrum such that its optical density at 360 nm is at least 100 times its optical density at 700 nm. The sol is ultrafine in particle size and is useful for the chemical sensitization of silver halide emulsions and for the preparation of development layers for the silver complex diffusion transfer copying process or the production of optical filters.

Abstract: The incorporation of dopant during the precipitation of silver halide grains. The silver halide grains are formed by a double jet, accelerated flow technique. After addition of about 65 to 90% of the silver halide mass to be precipitated, a dopant solution of an Group VIB salt in an amount of between about 0.2 and about 1.0 mg salt per mole of silver is added to the precipitation dispersion. The dispersion formation is then allowed to complete by continuing the double jet precipitation technique until a desired grain size is reached. Grains formed by this process will have their outer third comprising the Group VI metal salt with the silver halide. In the preferred method the Group VIB metal salt added is a selenium salt comprising potassium selenocyanate.

Abstract: The invention is generally accomplished by forming a silver halide emulsion and during precipitation adding iridium and selenium in an amount effective to decrease reciprocity failure with substantially no decrease in speed. In a preferred form, a photographic element is formed comprising of bromoiodide emulsion having about 3 to about 88 nanograms of iridium per square meter of silver halide grain surface area and about 42 to about 487 nanograms of selenium per square meter of silver halide grain surface area. It is also preferred that the iridium and selenium be added at a point after the precipitation has proceeeded to a point wherein at least half of the silver to be added is present.

Abstract: A silver halide photographic material comprising a support having thereon at least one silver halide emulsion layer, characterized in that at least one silver halide emulsion layer contains at least one compound represented by the following general formula (I), (II) or (III): ##STR1## wherein Q, X, Y, Z.sub.1, Z.sub.2, A, T.sub.1, T.sub.2 and T.sub.3 are as defined in the specification.

Abstract: A silver halide photographic emulsion containing silver halide grains having a silver chloride content of not less than 90 mol % and a method for preparing thereof are disclosed, wherein the silver halide grains are obtained by forming said silver halide grains in the presence of a water-soluble iridium compound and a nitrogen-containing heterocyclic compound capable of forming sparingly-soluble silver salt; and by controlling the addition of said iridium compound, whereby the photographic emulsion is improved in the dependence of gradation on exposure intensity.

Abstract: The present invention relates to a silver halide emulsion subjected to selenium sensitization in the presence of a palladium compound in an amount of 5.times.10.sup.-5 mol or more per mol of a silver halide. In addition to selenium sensitization, the emulsion may be subjected to sulfur sensitization and/or gold sensitization. In a process of manufacturing the silver halide emulsion, the palladium compound is preferably added to the emulsion before chemical sensitization.

Abstract: Photographic, gelatino, silver halide emulsions exhibiting improved speed/fog ratio and good hardening are described. These emulsions are made by sensitizing with 1-naphthol-4-sulfonic acid and by adding an aliphatic polyol thereto.

Abstract: A direct positive photosensitive material composed of a support having thereon at least one photosensitive emulsion layer comprising non-prefogged internal latent image silver halide grains and at least one compound represented by formulae (I), (II), (III) or (IV): ##STR1## wherein M.sub.1 represents hydrogen, a cation or a protective group capable of being cleaved by an alkali; and Z represents an atomic group necessary for forming a 5-membered or 6-membered substituted or unsubstituted ring selected from a heterocyclic ring and a condensed heterocyclic ring; ##STR2## wherein Z.sub.1 represents an alkyl group containing from 1 to 18 carbon atoms, an aryl group containing from 6 to 18 carbon atoms or a heterocyclic group; Y.sub.1 and Y.sub.2, which may be the same or different, each represents an atomic group necessary for forming an aromatic ring containing from 6 to 18 carbon atoms or a heterocyclic ring; M represents a metal atom or an organic cation; and n is an integer of 2 to 10.

Abstract: A silver halide photographic light-sensitive material includes a support and at least one layer of silver halide emulsion formed on the support. The emulsion layer contains silver halide grains which have been subjected both to reduction sensitization while growing and to at least one chemical sensitization selected from the group consisting of gold sensitization, sulfur sensitization, and noble-metal sensitization. Each of the silver halide grains has at least 5 mol % of silver iodide on a surface thereof.

Abstract: Light-sensitive silver halide photographic materials are disclosed comprising a support and silver halide emulsion layer or layers, wherein at least one of said silver halide emulsion layers contains tabular silver halide grains having an average diameter:thickness ratio of at least 3:1 and at least one resorcinol.The light-sensitive materials can be advantageously used in high temperature processing without causing serious fog problems.

Abstract: Color photographic recording material having a layer support and at least one silver halide emulsion layer sensitive to blue light, in which the silver halide of the blue sensitive silver halide emulsion layer is sensitized with a blue sensitizer of the J-band type and contains at least 95 mol % of silver chloride is distinguished by high sensitivity with low fog.