Abstract: There is disclosed a process for producing a silver halide emulsion comprising sulfur sensitizing a silver halide emulsion for photography containing a chloride rich silver halide comprising 80 mole % or more of silver chloride under the conditions of pAg and/or temperature during the sulfur sensitization which are constituted of at least two different steps with lapse of time.According to this invention, there is provided a silver halide emulsion which can give a good image without any change, can exhibit advantages of silver chloride, and is improved in the drawbacks of high fog and poor shelf-stability of silver chloride.

Abstract: A silver halide photographic emulsion is described, which has halogen composition comprises at least 60 mole % of silver chloride, 40 mole % or less of silver bromide, and 5 mole % or less of silver bromide. Grain formation is performed in the presence of a silver halide solvent selected from the group consisting of tetrasubstituted thioureas and organic thioethers, and from 10.sup.-8 to 10.sup.-5 mole of a water-soluble iridium compound per mole of silver halide. This photographic emulsion exhibits high sensitivity and provides high contrast even by flash exposure. Thus, it is useful for the production of light-sensitive materials to be used in the production of printing plates in accordance with photographic engraving.

Abstract: A silver halide light-sensitive photographic material comprises a support and a Lippmann emulsion layer on the support containing a silver halide and at least one compound of the following formula in a quantity of at least 3.5.times.10.sup.-3 mole per mole of the silver halide of the Lippmann emulsion layer: ##STR1## wherein Z represents an atomic group necessary to form a heterocyclic ring; Y is a hydrogen atom or --S--R.sub.1 group; R and R.sub.1 are each a hydrogen atom, an alkali-metal atom, ammonium or an alkyl group; X and X.sub.1 are each a divalent organic group; m and m.sub.1 are each 0 or 1; and n is an integer of up to 3, provided if n is 0, Y is --S--R.sub.1 group.The silver halide light-sensitive photographic material is developed in a developer containing at least 0.6 mole per liter of sulfurous ions.

Abstract: The use of oxythioamido substituted arylhydrazides in producing images in silver halide photographic elements is disclosed. The oxythioamido substituted arylhydrazide can be incorporated in photographic silver halide emulsions. The oxythioamido substituent is capable of promoting adsorption of the arylhydrazide to silver halide grain surfaces. In negative working surface latent image forming emulsions the oxythioamido substituted arylhydrazides permit higher speeds to be achieved. In direct positive internal latent image forming emulsions increased nucleation activity can be achieved.

Abstract: A method for forming a photosensitive element which comprises contacting silver halide in a plurality of spaced depressions in a surface with a mixture of a silver halide solvent and preformed sensitivity centers.

Abstract: Blended emulsions for use in forming a direct-positive image are disclosed. The emulsions are comprised of a first, radiation-sensitive core-shell grain population having a relatively low coefficient of variation and a second, substantially smaller size grain population capable of internally trapping photolytically generated electrons. Photographic elements incorporating the blended emulsions exhibit improved covering power and can exhibit enhanced speed.

Abstract: Photographic elements particularly adapted for forming direct-positive images are disclosed in which a radiation-sensitive core-shell emulsion layer and a silver halide emulsion layer incapable of forming a surface latent image within the direct-positive exposure latitude of the first emulsion layer and containing a grain population capable of internally trapping photolytically generated electrons are both present. The photographic elements are capable of exhibiting increased covering power, greater maximum density, and increased speed.

Abstract: High aspect ratio chemically and spectrally sensitized tabular grain silver halide emulsions, photographic elements incorporating these emulsions, and processes for the use of the photographic elements are disclosed. In the tabular grain emulsions the silver halide grains having a thickness of less than 0.3 micron and a diameter of at least 0.6 micron have a high aspect ratio and account for at least 50 percent of the total projected area of the silver halide grains present.

Abstract: Photographic elements particularly adapted for forming direct-positive images are disclosed in which a radiation-sensitive core-shell emulsion layer and a silver halide emulsion layer incapable of forming a surface latent image within the direct-positive exposure latitude of the first emulsion layer and containing a grain population capable of internally trapping photolytically generated electrons are both present. The photographic elements are capable of exhibiting increased covering power, greater maximum density, and increased speed.

Abstract: A process for the preparation of an internal latent image type silver halide emulsion containing silver halide grains comprising a central core of silver halide doped with metal ions, chemically sensitized or a combination thereof and an outer shell of silver halide covering at least light-sensitive sites of the central core characterized in that the surface of the silver halide grains are chemically sensitized in the presence of a polymer containing the repeating unit represented by general formula (I) ##STR1## wherein symbols R.sup.1 and Q are defined in the specification.

Abstract: An internal latent image silver halide emulsion is disclosed comprising core/shell silver halide particles having a chemically sensitized surface which are composed of a core of silver halide doped with metal ions and/or subjected to chemical sensitization and a shell which covers said core as far as to do at least the sensitive sites of said core and a binder, wherein said silver halide emulsions contain a polymer containing a repeating unit represented by the following general formula (I) in an amount of 2 mg to 1000 mg per mole of silver as the weight of said repeating units in said polymer: ##STR1## wherein R.sup.1 represents a hydrogen atom or an alkyl group and Q represents a group selected from the group consisting of the following (1)-(4): ##STR2## wherein q represents an integer of 2 to 4, ##STR3## wherein R.sup.2 and R.sup.3 each represents a hydrogen atom or an alkyl group, ##STR4## wherein Z.sup.

Abstract: A silver halide photographic light-sensitive material comprising a support having coated thereon at least one silver halide emulsion layer. The material contains at least one compound selected from the group consisting of a compound represented by the following general formula (I) and a compound represented by the following general formula (II) in at least one layer of the silver halide emulsion layer and other hydrophilic colloid layers thereof; ##STR1## wherein R represents an alkyl group having 1 to 6 carbon atoms which may be substituted, an aryl group having 6 to 11 carbon atoms which may be substituted, or an aralkyl group having 7 to 12 carbon atoms which may be substituted; A represents a .sigma. bond or a divalent connecting group which links R and the nitrogen atom; R.sub.1 and R.sub.2 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms which may be substituted, or an aralkyl group having 7 to 11 carbon atoms which may be substituted, or when A represents a .sigma. bond, R.sub.

Abstract: A silver halide photographic light-sensitive material is described comprising a support having thereon at least one silver halide emulsion layer wherein the silver halide emulsion has been chemically ripened in the presence of at least one compound containing at unit represented by the formula ##STR1## wherein M represents hydrogen, an alkali metal atom, or NH.sub.4. The silver halide photographic light-sensitive material shows high sensitivity without an accompanying increase in fog.

Abstract: A silver halide photographic emulsion characterized in that it comprises silver halide grains which are reduction-sensitized during the process of growing said grains and containing a compound of the formula ##STR1## wherein R.sub.1 and R.sub.2 are selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an acyl group and a cycloalkyl group and R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, a carboxyl group, an aldehyde group, an amino group, a sulfo group, an alkylthio group, an acylamino group, an aryloxy group, an arylthio group, an alkylamino group, an alkoxycabonyl group and a sulfonamide group. The emulsion exhibits both high sensitivity and improved stability as compared with prior art compositions.

Abstract: Derivatives of thiazolidine are used in photographic silver halide emulsions to increase their speed 40% or more with little or no increase in emulsion fog. Lower silver halide coating weights are thus possible.

Abstract: A radiation-sensitive emulsion for use in forming a direct-positive image is disclosed. The emulsion is comprised of core-shell silver halide grains. The shell portions of the grains contain polyvalent metal ions to reduce rereversal.

Abstract: The sensitivity of a gelatino-silver halide emulsion is improved by adding glutaraldehyde bisulfite in combination with benzene sulfinic acid during the preparation of the silver halide, viz. when a silver salt is mixed with a halide to precipitate a silver halide.

Abstract: A method for forming a high contrast negative photographic image, which comprises imagewise exposing a photographic material comprising a support having thereon at least one photographic silver halide emulsion layer with the photographic silver halide emulsion layer or at least one hydrophilic colloid layer of the photographic material containing a compound of the general formula (I)R.sup.1 --NHNHCO--R.sup.2 (I)wherein R.sup.1 represents an aryl group, and R.sup.2 represents a hydrogen atom, a phenyl group, or an unsubstituted alkyl group containing 1 to 3 carbon atoms, and then developing the imagewise exposed material in the presence of a hydroquinone compound of the general formula (II) ##STR1## wherein R.sup.3, R.sup.4, R.sup.5 and R.sup.6, which may be the same or different, each represents a hydrogen atom, a sulfo group, an alkyl group, an aryl group, an aralkyl group, a heterocyclic group, or a group of the formula --O--R.sup.7 or --S--R.sup.7 where R.sup.

Abstract: A silver halide photographic material is described, comprising an emulsion which is chemical-ripened in the presence of a compound having the formula (I) or (II), ##STR1## wherein R.sub.1 is hydrogen, an alkali metal ion, or an ammonium ion; R.sub.2 is an alkyl group, an alkoxy group, an aryloxy group, an acyl group, an amino group, a substituted amino group, a halogen atom, an acyloxy group, an acylamino group, a carbamoyl group, a nitro group, an aryl group, an allyl group, a sulfo group or a carboxy group; Y represents a divalent linking group; and n is 0, 1, or 2; such emulsions show high sensitivity without fog and have good stability.

Abstract: A heat developable silver image forming material comprising:(a) an organic silver salt oxidizing agent;(b) a compound or a composition capable of forming a photosensitive silver compound by reaction with the organic silver salt oxidizing agent (a);(c) a reducing agent for silver ion; and(d) a compound having a unit of ##STR1##

Abstract: Tetraazaundecane and certain derivatives thereof serve as a chemical sensitizer for negative silver halide emulsions.

Abstract: A silver halide photographic light-sensitive element is described comprising a support having thereon at least one silver halide emulsion layer, wherein at least one compound represented by formula (I) is incorporated in the silver halide emulsion layer or in another hydrophilic colloid layer: ##STR1## wherein X represents a hydroxy group or a group represented by ##STR2## wherein R.sup.2 and R.sup.3 (which may be the same or different) each reprsents hydrogen, an alkyl group, or an aryl group; R.sup.1 represents a sulfur-containing saturated heterocyclic group or a group represented by -A-S-B, wherein A represents an alkylene group and B represents hydrogen, an alkyl group, or an aryl group; and Z represents an atomic group forming a 5-membered or 6-membered unsubstituted or substituted carbocyclic ring.In the silver halide photographic light-sensitive element, the so-called "latent image fading" phenomenon is prevented without accompanying degradation of other photograhic properties.

Abstract: Narrow grain size distribution silver halide emulsions are prepared by:1. Forming photosensitive silver halide grains in the presence of a water-soluble thiocyanate compound with a halide/silver molar ratio ranging from not more than about 5% molar excess of halide to not more than about a 25% molar excess of silver; and2. Growing said grains in the presence of said water-soluble thiocyanate compound for a time sufficient to grow said grains to a predetermined grain size distribution.

Abstract: A novel method of forming high contrast silver images is provided. The method comprises steps of (1) imagewisely exposing a light-sensitive silver halide photographic material, and (2) treating the exposed material with a developer having superadditivity. The method is characterized by the co-existence of an oxidizing agent, and a water-insoluble ion pair formed by a water-soluble cationic compound such as quaternary ammonium or tertiary sulfonium salt and a water-soluble anionic compound such as organic sulfate. The method realizes high contrast photographic images by using a developer having a good preservability, without contamination of the developer, within a short period of time for the development. There is also provided a light-sensitive silver halide photographic material herein.

Abstract: A silver halide photographic light-sensitive material is described containing a compound comprising at least one unsaturated group and at least one betaine group in at least one layer thereof.The photographic light-sensitive material has a high sensitivity without being accompanied by an undesirable increase in the formation of fog.

Abstract: Photographic silver halide emulsions are stabilized by aminocarboxylic acids.

Abstract: Fine crystals characterized by improved morphological homogeneity and a narrow size distribution are prepared by introducing a solution of a crystallizable solute in a solvent into a bed of small inert continuously moving solid particles and initiating crystallization within the solution while it is in contact with the moving particles. The process finds application in the manufacture of diverse crystalline products such as, for example, in the formation of metal oxalates, phosphorescent compounds, and silver halide crystals, as well as in the purification of both organic and inorganic materials.

Abstract: A process for preparing silver halide emulsions having high sensitivity and contrast by adding water-soluble iridium compounds during precipitation or physical ripening and adding water-soluble iodide compounds and sulfer sensitizers during chemical ripening.

Abstract: The speed of monodisperse photographic emulsions made by balanced doubled jet precipitation and converted into a AgBr and/or AgBrI emulsion is increased by ripening in the presence of sulfur compounds at a pH between 8 and 9.5.

Abstract: A silver halide photographic emulsion containing silver halide grains formed in the presence of a silver halide solvent of the formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each a subtituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group (e.g., allyl group), a substituted or unsubstituted aryl group or a substituted or unsubstituted nitrogen-containing heterocyclic ring; or R.sub.1 and R.sub.2, R.sub.2 and R.sub.3, and R.sub.3 and R.sub.4 when taken together may form a 5- or 6-membered heterocyclic ring; provided at least one of R.sub. to R.sub.4 is a 5- or 6-membered nitrogen-containing heterocyclic ring, an alkyl group or aryl group substituted with an amino group, an alkyl grop substituted with a nitrogen-containing heterocyclic ring, or R.sub.1 and R.sub.2, R.sub.2 and R.sub.3, or R.sub.3 and R.sub.4 combine to form a 5- or 6-membered nitrogen-containing heterocyclic ring containing at least two nitrogen atoms.

Abstract: A silver halide photographic emulsion containing the compound represented by the formula (I):R.sub.1 --(X--R.sub.3).sub.m --X--R.sub.2 (I)wherein R.sub.1 and R.sub.2 each represents an alkyl group containing 1 to 5 carbon atoms substituted with two or more substituents selected from --OH, --NHR.sub.4, --COOR.sub.4, --CONH.sub.2, --SO.sub.3 H, --COOM, or --SO.sub.3 M, R.sub.3 represents an alkylene group containing 1 to 4 carbon atoms which may be substituted by --OH, R.sub.4 represents a hydrogen atom or an alkyl group containing 1 to 5 carbon atoms, X represents a sulfur or oxygen atom, provided at least one X is a sulfur atom, m represents 0 or an integer of 1 to 4, and M represents an alkali metal atom.

Abstract: There are described novel acyclic silver complexing agents which are useful as silver halide solvents in photographic products, processes and compositions. Also disclosed are photographic compositions, products and processes in which the complexing agents are utilized.

Abstract: A method of forming an extremely high-contrast negative photographic image which comprises image-wise exposing a photographic light-sensitive material comprising a support having thereon a mono-disperse silver halide emulsion layer containing surface latent image type silver halide grains and also containing a compound represented by the following general formula (1):R.sup.1 NHNHCOR.sup.2 (I)wherein R.sup.1 represents an aryl group, R.sup.2 represents a hydrogen atom, a phenyl group or an unsubstituted alkyl group having 1 to 3 carbon atoms, and then processing the exposed light-sensitive material in the presence of a compound having a thioamido moiety in the molecule thereof.

Abstract: This disclosure relates to high chloride silver halide emulsions and photographic elements containing silver halide grains which are internally doped with cadmium, lead, zinc or mixtures thereof in concentrations up to 7.times.10.sup.-5 mole/mole of silver halide.

Abstract: There are described novel acyclic silver complexing agents which are useful as silver halide solvents in photographic products, processes and compositions. Also disclosed are photographic compositions, products and processes in which the complexing agents are utilized.

Abstract: A light-sensitive silver halide reproduction material of high gradation stability which contains a disulfide compound substituted by two heterocyclic radicals, and a thiazolidine compound.

Abstract: A silver halide photographic light-sensitive material having at least one silver halide photographic emulsion layer comprising substantially surface latent image type silver halide grains, and containing in said photographic emulsion layer or at least one of other hydrophilic colloid layers a compound represented by the following general formula (I): ##STR1## wherein X.sup.1 represents a group containing a ##STR2## moiety, Ar.sup.1 and Ar.sup.2 each represents a substituted or unsubstituted aromatic group, B represents a divalent linking group, n is 0 or 1, and R.sup.1 represents a hydrogen atom, an unsubstituted alkyl group, or a substituted or unsubstituted aryl group.

Abstract: Light-sensitive silver halide photographic materials to be treated with a hydroquinones-containing developing solution which material comprises a support and at least one hydrophilic colloidal layer coated thereon which contains silver halide grains having an average grain size of 0.05 to 1.5.mu., a tetrazolium compound and a sensitizing dye.

Abstract: A method of preparing photograhic silver iodide, containing emulsions is provided.

Abstract: Radiographic silver halide emulsions are provided comprising silver halide grains the average silver halide grain diameter of which is at least 250 nm and which consist substantially of silver bromide dispersed in a hydrophilic colloid binder e.g. gelatin wherein the silver halide grains have high primitive surface sensitivity for direct exposure to penetrating radiation and are substantially regular in shape and wherein the ratio of hydrophilic colloid to silver halide is at most about 1.0. These emulsions have high sensitivity for direct exposure to penetrating radiation and are themselves substantially insensitive to formation of pressure marks upon rapid processing.

Abstract: A process for sensitizing photographic gelatino-silver halide emulsions with glutaraldehyde bisulfite in combination with benzene sulfinic acid.

Abstract: A silver halide photographic material for use in flash exposure of less than 1/10000 second comprising 10.sup.-8 to 5.times.10.sup.-7 moles/moles of silver halide of at least one compound belonging to Group VIII of the Periodic Table and at least one of the sensitizing dyes of the following formulas (I) or (II) and which is capable of sensitizing silver halide at less than 550 nm: ##STR1## wherein R, R.sub.1, R.sub.2, R.sub.3, Q, X.sup.(-), Z, Z.sub.1, Z.sub.2, n, n.sub.1, n.sub.2 and n.sub.3 are as defined in the specification.