Abstract: A silver halide photographic light-sensitive material and high contrast negative image forming process using them are disclosed. The material comprises a support having thereon at least one silver halide emulsion layer in which said silver halide emulsion layer or other hydrophilic colloid layer contains at least one hydrazine derivative, at least one cationic dye selected from a cyanine dye, a hemicyanine dye and a rhodacyanine dye, and L-ascorbic acid, and has photographic characteristics of giving very high contrast of over 10 in .gamma., giving high practical Dmax and sensitivity, and causing less black peppers using a stable developer and having optimum spectral sensitivity for spectral energy distributions of various light sources.

Abstract: Liquid petroleum sulfonates are useful alone or in combination with less lipophilic anionic surfactants in the preparation of dispersions of water-insoluble photographic addenda, such as couplers and ultraviolet absorbers, in hydrophilic colloid compositions. Such dispersions are useful in photographic elements. Crystallization of the addenda is inhibited and, for some addenda, other advantages are obtained.

Abstract: Compounds which include a quaternary group connected to a pyrimidine residue through a linkage are disclosed. These compounds are useful as silver halide solvents in photographic products, processes and compositions.

Abstract: In a silver halide photographic material for tanning development, comprising a support base coated with a substantially unhardened hydrophilic binder layer including a light-sensitive silver halide emulsion reactively associated with a tanning developer and a dispersion of colloidal silver, the tendency of the hydrophilic binder to become water-insoluble during storage can be prevented by adjusting the pAg of the colloidal silver dispersion to values in the range from 6.5 to 9.5 with a 1-phenyl-5-mercaptotetrazole compound before coating.

Abstract: A silver halide color photographic light-sensitive material comprising a support having thereon at least one silver halide emulsion layer, the color photographic light-sensitive material containing a compound capable of releasing a group represented by the general formula (I) described below upon the reaction with the oxidation product of a developing agent: ##STR1## wherein W and Z each represents an oxygen atom, a sulfur atom or a group of ##STR2## X.sub.1, X.sub.2, X.sub.3, X.sub.4 and X.sub.5 each represents a hydrogen atom or an organic residue; PUG represents a photographically useful group; n represents 1 or 2; any two of X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5 and PUG each represents a divalent group and may be connected to each other to form a cyclic structure; and when n represents 2, two Z's, two X.sub.3 's and two X.sub.4 's may be the same or different.

Abstract: A silver halide photographic material which comprises a support having coated thereon a light-sensitive silver halide emulsion layer, wherein the photographic material contains at least one blocked photographic agent represented by the following general formula (I): ##STR1## wherein A represents a photographic agent moiety which is bonded to a blocking moiety through a hetero atom, or a precursor thereof; R.sup.1, R.sup.2 and R.sup.3 each represents a hydrogen atom, or a substituent group; and Z represents atoms necessary to form a carbocyclic ring or a heterocyclic ring (except for a heterocyclic ring which contains an NH group at the position adjacent to the carbon atom to which R.sup.1 is attached). The blocked photographic agent is completely stable upon storage of the photographic material, and releases a photographic agent at a desired time upon processing. The blocked photographic agent also exhibits its function to a substantial degree over a wide range of pH.

Abstract: A latex composition having utility in articles such as photographic elements is disclosed. The composition comprises loadable polymer particles having recurring units a, b and c wherein:component a is 10 to 100 weight percent of a tetrahydrofurfuryl monomer having the structure: ##STR1## in which R.sub.1 represents O or NH; andR.sub.2 represents H or lower alkyl of about 1 to 6 carbon atoms;component b is 0 to 20 weight percent of a hydrophilic monomer andcomponent c is 0 to 90 weight percent of a hydrophobic monomer.

Abstract: Photographic elements and processes are described which employ a compound containing a hydrazide moiety attached by a linking group, comprising an acidic group or an active methylene group adjacent to an acidic group, to a heteroatom of a moiety containing a photographically useful group comprising a photographic dye or precursor thereof or a photographic reagent; wherein:(a) the hydrazide moiety is capable of being oxidized to an azo group by an oxidized developing agent,(b) the azo group formation causes the release of the photographically useful group, and(c) the released photographically useful group does not contain the linking group or the nitrogen atoms of the hydrazide moiety.

Abstract: A silver halide photographic material comprising a support having thereon at least one light-sensitive silver halide emulsion layer having associated therewith at least one blocked photographic reagent represented by formula (I) or (II); ##STR1## wherein, A represents a moiety of a photographic reagent or a moiety of a precursor of a photographic reagent bonded to the ring containing Z through a hetero atom; Y.sup.1, and Y.sup.2 and Y.sup.3 each represents a hydrogen atom or a substituent, or Y.sup.1 and Y.sup.3 in formula (I) together form a ring; Z represents an atomic group necessary for forming a carbon ring or a heterocyclic ring; and n represents 1 or 2.The silver halide photographic material is stable under storage conditions.

Abstract: A silver halide color photographic light-sensitive material comprising a support having thereon at least one silver halide emulsion layer, the color photographic light-sensitive material containing a compound capable of releasing a group represented by the general formula (I) described below upon the reaction with the oxidation product of a developing agent: ##STR1## wherein W represents an oxygen atom, a sulfur atom or a group ##STR2## (wherein R represents a hydrogen atom or an organic residue); X represents an electron withdrawing substituent; Y represents a hydrogen atom or a substituent; PUG represents a photographically useful group or a precursor thereof; X and Y each represents a divalent group and may be connected to each other to form a cyclic structure; and when W represents the group ##STR3## and R represents an organic residue, R and X or R and Y each represents a divalent group and may be connected to each other to form a cyclic structure.

Abstract: A process for forming an image comprising a heating step is described, wherein a photographic material is heated in the presence of a compound represented by formula (I) ##STR1## wherein X represents an atomic group completing a carbocyclic aromatic ring or a heterocyclic aromatic ring; R.sup.1 is selected from groups represented by formulae (A), (B), and (C) ##STR2## in which R.sup.11 and R.sup.12 each represents a substituted or unsubstituted alkyl group, a cycloalkyl group, a substituted or unsubstituted alkenyl group, an aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, an alkyloxy or aryloxy group, an alkylthio or arylthio group, or a substituted or unsubstituted amino group, or R.sup.11 and R.sup.12 together form a 5-membered or 6-membered ring; R.sup.2 represents a group selected from the groups represented by R.sup.11 ; R.sup.1 and R.sup.

Abstract: Photographic recording materials which contain a developer substance or a precursor thereof produce better results if in addition they contain a sulphite, a disulphite or a compound capable of releasing sulphite in the photographic material.

Abstract: A direct positive silver halide photographic emulsion which is able to provide a high maximum density and a low minimum density, and having a high developing progress. The emulsion contains at least one of the sensitizing dyes represented by following general formulate I, II, III, and IV and at least one of the compounds represented by general formulae V and VI; ##STR1## The substituents are defined in the specification.

Abstract: A method of processing a photographic material which contains a light-sensitive silver halide emulsion layer having associated therewith a blocked photographic agent capable of releasing a photographically useful agent by ring cleavage of a 4- to 7-membered ring containing at least one carbonyl group in the presence of a hydroxylamine, whereby both high stability of the photographic material upon storage and timely release of the photographically useful agent upon processing are achieved.

Abstract: Liquid petroleum sulfonates are useful alone or in combination with less lipophilic anionic surfactants in the preparation of dispersions of water-insoluble photographic addenda, such as couplers and ultraviolet absorbers, in hydrophilic colloid compositions. Such dispersions are useful in photographic elements. Crystallization of the addenda is inhibited and, for some addenda, other advantages are obtained.

Abstract: Photographic elements and assemblages are described which employ nondiffusible N',N'-diaromatic carbocyclic--or diaromatic heterocyclic--sulfonohydrazide compounds which are capable of releasing photographically useful groups in an imagewise manner as a function of silver halide development.

Abstract: A silver halide photographic light-sensitive material is described, comprising a support having thereon a light-sensitive silver halide emulsion layer having associated therewith a blocked photographic agent represented by formula (I) ##STR1## wherein A represents a photographically useful agent moiety, which may have a timing group; X.sup.1 and X.sup.2 each represents a carbonyl group, a sulfonyl group, or a sulfinyl group; Z represents an atomic group forming a 5-membered, 6-membered, or 7-membered ring; R.sup.1 and R.sup.2, which may be the same or different, each represents a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, a sulfonyl group, or a heterocyclic group; R.sup.3 represents an alkyl group, an alkenyl group, a cycloalkyl group, a heterocyclic group, an aryl group, or an aralkyl group; m represents 0, 1, or 2; n represents 0 or 1; and the total of m+n is 1, 2, or 3.

Abstract: A silver halide color photographic light-sensitive material comprising a support having thereon at least one silver halide emulsion layer, the color photographic light-sensitive material containing a coupler which releases a compound after the coupling reaction with the oxidation product of a developing agent, the released compound being capable of releasing further a photographically useful group by an oxidation-reduction reaction with the oxidation product of another developing agent. The compound used in the present invention is chemically stable and can release a photographically useful group under control; therefore the silver halide color photographic light-sensitive material containing the compound has good stability during storage and high sensitivity and provides a color image having good image qualities such as sharpness, graininess, color reproducibility, etc.

Abstract: A silver halide photographic material is disclosed. It contains per 100 g of silver at least 40 mg of a water-soluble compound comprising an element of group VIII of the periodic table and having a molecular weight of at least 100, and 1.2 to 120 mg of a black-and-white silver halide developing agent. The material has improved gradation characteristics and is subject to minimum variation in photographic characteristics.

Abstract: Photographic elements and assemblages are described which employ nondiffusible compounds which release photographically useful groups in an imagewise manner as the result of a .beta.-elimination reaction.

Abstract: There is provided a developer for use in a one-step process for the development of exposed film resulting in an exposurewise pattern of silver particles which are large enough to be used as printing elements in ink-printing techniques, providing a wide range of densities in the developed film. The developer is based on a buffered system of a developing agent, a sulfinic acid salt of the type HO-R-SO.sub.2.M..times.H.sub.2 O where R is a hydrocarbyl group and M is a cation, and a formaldehyde source, with conventional adjuvants such as anti-fogging agents and the like. Instead of the sulfinic acid salt defined above there may be used any compound which upon dissociation in a aqueous medium results in the same active ionic species.

Abstract: A silver halide photographic light-sensitive material is described, comprising a support having provided thereon at least one light-sensitive silver halide emulsion layer associated with a substantially immobile, positive one-equivalent redox compound capable of releasing a photographically useful compound or a precursor thereof as a result of a redox reaction, said compound being represented by formula (I) ##STR1## wherein Acp represents an anion center precursor capable of causing --Z--Q to be released by a quinonemethide type releasing reaction when being reduced R.sup.1 and R.sup.

Abstract: A silver halide photographic printing paper is described, comprising a support and a photographic layer containing a silver halide developing agent, wherein a dispersion of an oil-soluble brightening agent in a high boiling point organic solvent having a specific inductive capacity of 7.5 or less is contained in the photographic layer. This printing paper yields a background of high whiteness even when processed under rapid processing conditions.

Abstract: A heat-developable color light-sensitive material comprising a support having thereon at least: (1) a light-sensitive silver-halide, (2) a coupler capable of coupling with an oxidation product of a developing agent, (3) a hydrophilic binder, and (4) at least one compound represented by the following general formula (Z): ##STR1## the substituents A, R.sub.1, R.sub.2 R.sub.3, R.sub.4, X and R.sub.5 are defined herein.The heat-developable color light-sensitive material containing the developing agent or the precursor thereof represented by the general formula (Z) which is excellent in stability during storage, silver developing property and coupling property has good preservability and can provide color images having a high S/N ratio and a high image density.

Abstract: Silver halide photographic materials with higher sensitivity and less fogging having at least one silver halide emulsion layer over a photographic base or support wherein the emulsion of said emulsion layer substantially contains core/shell-type silver halide grains or core/shell-type monodisperse silver halide grains, core portion of said grain containing silver iodide in a greater amount than that contained in shell portion of said grain and said emulsion is subjected to chemical ripening in the presence of a labile selenium compound, optionally with coexistence of a silver halide solvent, and said emulsion may contain further a specific phenol compound.

Abstract: Compounds of the formula ##STR1## wherein L is a direct bond or consists of a chain of carbon atoms or of a divalent ring system, R.sub.1 to R.sub.4 are hydrogen or alkyl, R.sub.5 or R.sub.6 are hydrogen, alkyl or aryl, or R.sub.5 together with R.sub.6 complete a ring system, and R.sub.7 is hydrogen or a group of the formula ##STR2## wherein L, R.sub.5 and R.sub.6 are as defined. These compounds are useful developing agents for activation processing.

Abstract: A silver halide photographic light-sensitive material is described which comprises a support having thereon a light-sensitive silver halide emulsion layer, wherein the photographic light-sensitive material therein contains a blocked photographic agent capable of releasing a photographically useful agent and the blocked photographic agent has a carbonyl group or thiocarbonyl group to which a hydrogen atom or a carbon atom is directly bonded and is substituted with a photographically useful group which is capable of being released upon an intramolecular nucleophilic attack by the oxygen atom in the carbonyl group or the sulfur atom in the thiocarbonyl group.The precursor of photographic agent is completely stable during storage prior to use of the photographic light-sensitive material, and releases a photographic agent at a desired time upon the processing of the photographic light-sensitive material. The precursor also exhibits its function to a substantial degree in a relatively low pH range.

Abstract: A direct positive silver halide photographic emulsion which is able to provide a high maximum density and a low minimum density and having a high developing progress. The emulsion contains at least one of the sensitizing dyes represented by following general formula I and at least one of the compounds represented by general formula II:Formula I: ##STR1## Formula II: ##STR2## The substituents are defined in the specification.

Abstract: There is described a photographic system wherein development of an exposed photosensitive element with an aqueous alkaline processing composition is effected in the presence of a compound which is a salt of a radical of a substituted phenylmercaptoazole complexed with a radical of a quaternary. The salts are either insoluble or have extremely low solubility in water and become soluble, and photographically active, in alkaline environment.

Abstract: Photographic silver halide material containing a ballasted electron-donor precursor compound yielding by alkaline hydrolysis an electron-donor compound (ED-compound) capable (1) of donating electrons to an oxidized electron-accepting silver halide developing agent e.g. for scavenging it, said electron-donor precursor compound corresponding to the following general formula: ##STR1## wherein: R represents hydrogen or a substituent, e.g. an acyl group, which on hydrolytic removal allows the replacement of R by H,R.sup.1, R.sup.2 and R.sup.3 (same or different) are hydrocarbon substituents or R.sup.3 is H, andZ and Y represent the necessary atoms to close a benzene ring that may be substituted or form a fused ring system.

Abstract: A photographic silver halide light-sensitive material is disclosed. The material is comprised of a support and a photographic layer or layers on the support. The photographic layer contains at least one of the compounds represented by the general formula: A--OCH.sub.2 --Z (wherein A is a group capable of undergoing cleavage on application of alkali hydrolysis, and Z is a photographically useful group containing a nitrogen atom through which it is linked to the group A--OCH.sub.2 --). The compounds, i.e., photographically useful group precursors, as used herein are stable during the storage of the raw film and can release the photographically useful group at a controlled speed during development.

Abstract: A silver halide photographic light-sensitive material which comprises a support having thereon a light-sensitive silver halide emulsion layer, wherein the photographic light-sensitive material contains a blocked photographic agent therein represented by formula (I): ##STR1## wherein A represents a photographic agent moiety which is bonded to a blocking moiety through a hetero atom or a group which is bonded to a blocking moiety through a hetero atom and capable of releasing a photographic agent upon a subsequent reaction after the group is released; Y represents a hydrogen atom or a substituent; and Z represents an atomic group necessary to form a carbocyclic ring or a heterocyclic ring.The precursor of photographic agent is completely stable during the preservation of the photographic light-sensitive material and releases a photographic agent at a desired time upon the processing of the photographic light-sensitive material.

Abstract: A photographic material suited for the production of (an) azine dye image(s), and having at least one silver halide emulsion layer and/or a separate layer in water-permeable relationship with such an emulsion layer which contains:(1) a heterocyclic hydrazone compound,(2) a phenol, naphthol or active methylene coupler compound capable of forming on oxidative coupling with compound (1) an azine dye,(3) an electron transfer agent or ETA-compound capable of forming a positively charged semiquinone on oxidation with exposed silver halide,(4) a reducing agent capable of reducing the thus-formed semiquinone in acidic medium, and having in the pH range of 2-5, a polarographic half-wave potential (E 1/2) which is at least 40 mV more negative (according to the European Convention) than the polarographic half-wave potential of the ETA-compound in the same pH range, said material being suited for processing with a simple aqueous alkaline liquid, and(5) an acidic medium.

Abstract: Silver halide photographic elements for tanning development including tanning developers, which can diffuse into the gelatin layer containing them, can be improved if they are associated with non-diffusing hydroquinones. In the case where such tanning developer is hydroquinone or a derivative thereof, said elements include such diffusing hydroquinone associated with a hydroquinone derivative non-diffusing in the gelatin layer containing it. Such non-diffusing hydroquinones preferably are hydroquinones substituted with aliphatic chains containing a total of at least twelve carbon atoms and, more preferably, are dispersed in the layer dissolved in a high-boiling organic solvent.

Abstract: A silver halide photographic light-sensitive material which comprises a light-sensitive silver halide emulsion layer having associated therewith a blocked photographic agent, said blocked photographic agent being represented by the following general formula (I): ##STR1## wherein A represents a photographic agent moiety which is attached to a blocking moiety through a hetero atom; Z represents a divalent linkage group; p represents 0 or 1; X and Y each represents a substituent: m represents an integer of 0 to 4: and n represents an integer of 0 to 5.

Abstract: A photographic recording material. On a support are provided a silver emulsion halide layer and a photographic layer. The photographic layer contains an indole compound represented by the general formula (I): ##STR1## wherein PUG represents a photographically useful group, Ball represents an organic group which has enough molecular weight and/or disposition to render the compound non-diffusible during processing of the photographic recording material with an alkaline medium and wherein the Ball contains a nitrogen atom which is directly attached to the 5th or 6th position of the indole ring. R.sub.1 represents a halogen atom or a monovalent organic group. R.sub.2 represents a hydrogen atom or a low molecular group attached, through a carbon atom, to the 2nd position of the indole ring. "m" represents an integer of zero to 3.

Abstract: A silver halide photographic light-sensitive material containing a diffusion resistant coupler, a light-sensitive silver halide and at least one organic metal complex represented by the following general formula (I) in the same layer or different layers on a support. ##STR1## wherein M represents a divalent metal atom; R.sup.1 and R.sup.2, which may be the same or different, each represents an alkyl group having from 1 to 5 carbon atoms, a hydroxyalkyl group having from 1 to 5 carbon atoms, an alkoxyalkyl group having from 2 to 10 carbon atoms or an alkylsulfonamidoalkyl group having from 2 to 10 carbon atoms, or R.sup.1 and R.sup.2 may be bonded each other to form a heterocyclic ring together with the nitrogen atom; R.sup.3, represents a hydrogen atom, an alkyl group having from 1 to 5 carbon atoms or an alkoxy group having from 1 to 5 carbon atoms; and R.sup.4 and R.sup.

Abstract: There is disclosed a light-sensitive silver halide photographic material comprising at least one hydrophilic colloid layer containing microcapsules encapsulating a photographic treating reagent coated with a wall material, which can be dissolved at pH 7 or higher, provided on a support.The microcapsules of the present invention, can be effectively employed in a one-bath treatment method for forming a dye image. The bath is highly stable and the resulting images have extremely high color density.

Abstract: Process for the preparation of a photographic material comprising in at least one layer photographic useful compounds, e.g. color couplers or developers, which are occluded into solid polymer particles of 0.1 to 0.5 .mu.m in size.

Abstract: A silver halide photographic light-sensitive material containing at least one compound represented by the general formula (I): ##STR1## is disclosed. The compound of the invention has good stability over time. The material has improved developability and makes it possible to carry out simple and rapid processing. The material has good resistance with respect to fogging, stains and desensitization.

Abstract: A color photographic silver halide light-sensitive material is described, containing at least one member of the compounds represented by the general formula (I-a) and (I-b) in at least one layer thereof: ##STR1## (wherein all the symbols are defined in the appended claims). This color light-sensitive material can be subjected to rapid photographic processing; i.e., the compounds of the general formula (I-a) and (I-b) act as bleach accelerators, making it possible to perform rapid photographic processing without exerting adverse influences on photographic characteristics.

Abstract: A method for producing a photographic emulsion is disclosed. The method includes the process of adding a dispersion of a substantially water-insoluble photographic additive to a photographic emulsion. The dispersion being prepared merely by mechanically grinding and dispersing the photographic additive in a form of fine grain having a size of 1.mu. or less in an aqueous system adjusted to a pH value of 6 to 8 and controlled to a temperature of 60.degree. to 80.degree. C. The additive is included in the photographic emulsion without the need of an organic solvent. The emulsion of the invention can be easily and quickly coated to form a uniform layer.

Abstract: A color photographic silver halide light-sensitive material which prevents formation of color fog is disclosed, containing a negative gradation photographic silver halide emulsion which is substantially of the surface latent image type, and at least one compound represented by the general formula (I): ##STR1## wherein X represents --CONR.sup.1 R.sup.2, --COR.sup.1, --SO.sub.2 R.sup.1, or --SO.sub.3 R.sup.1 and wherein R.sup.1 and R.sup.2 each are selected from the group consisting of a hydrogen atom, a substituted or unsubstituted aliphatic group, and a substituted or unsubstituted aromatic group, and are selected such that may combine together to form a ring.

Abstract: A method for immunochemical assay of an antigen or antibody by labelling the antigen or antibody with a specific cyanine or merocyanine dye containing a carboxy group followed by effecting an immune reaction and photochemical processing thereof is provided. The amount of the antigen or antibody is measured in term of optical density of developed silver halide which is brought into contact with either the antigen-antibody reaction product or the unreacted material.This immunochemical assay method gives high detection sensitivity in a simple operation manner.

Abstract: A silver halide photographic light-sensitive material containing a diffusion resistant coupler, a light-sensitive silver halide and at least one compound represented by the following general formula (I) in the same layer or different layers on a support. ##STR1## Wherein R.sub.1 and R.sub.2, which may be the same or different, each represents a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms, or R.sub.1 and R.sub.2 may be bonded to each other to form a heterocyclic ring together with the nitrogen atom; R.sub.3, R.sub.4, R.sub.5 and R.sub.6, which may be the same or different, each represents a hydrogen atom, a halogen atom, a hydroxy group, an amino group, an alkoxy group, an acylamido group, a sulfonamido group, an alkylsulfonamido group or an alkyl group, or R.sub.1 and R.sub.6 or R.sub.2 and R.sub.3 may be bonded to each other to form a 5-membered or 6-membered ring; X represents HPF.sub.6 or HBF.sub.4 ; and n represents an integer from 1 to 3.

Abstract: This invention relates to photographic processes and products for forming an image in dye from a colorless precursor of a preformed image dye which is substituted with a moiety containing a thiazolidinyl group, said thiazolidinyl group (a) being capable of undergoing cleavage imagewise in the presence of an imagewise distribution of silver ion and/or soluble silver complex and (b) possessing a substituent on the carbon atom in the 2-position which upon cleavage of said thiazolidinyl group, undergoes a .beta.-elimination reaction followed by an intramolecularly accelerated nucleophilic displacement reaction, which moiety maintains the precursor in its colorless form at least until said thiazolidinyl group undergoes said cleavage. In a further embodiment, this sequence of reactions is used to release an imagewise distribution of a photographically useful reagent which reagent may be, for example, a photographically active reagent.

Abstract: This invention relates to photographic processes and products for forming an image in dye from a colorless precursor of a preformed image dye which is substituted with a moiety containing a thiazolidinyl group, said thiazolidinyl group (a) being capable of undergoing cleavage imagewise in the presence of an imagewise distribution of silver ion and/or soluble silver complex and (b) possessing a substituent on the carbon atom in the 2-position that undergoes a .beta.-elimination reaction upon said imagewise cleavage, which moiety maintains the precursor in its colorless form at least until said thiazolidinyl group undergoes said cleavage. In a further embodiment, an imagewise distribution of a photographically useful reagent, which reagent may be, for example, a photographically active reagent, is released as a carbamic acid by a .beta.-elimination reaction following the cleavage of a thiazolidinyl group whereby said reagent is provided with a solubilizing group at least during the initial stages of processing.

Abstract: This invention relates to photographic processes and products for forming an image in dye from a colorless precursor of a preformed image dye which is substituted with a moiety comprising a 1,3-sulfur-nitrogen group, said 1,3-sulfur-nitrogen group (a) being capable of undergoing cleavage in the presence of silver ion and/or soluble silver complex, and (b) possessing an amide substituent on the carbon atom in the 2-position that undergoes an intramolecularly accelerated cleavage reaction following the cleavage of said 1,3-sulfur-nitrogen group, which moiety maintains said precursor in its colorless form at least until the 1,3-sulfur-nitrogen group undergoes said cleavage. In a further embodiment, the cleavage of the amide substituent following the cleavage of the 1,3-sulfur-nitrogen group is used to provide an imagewise distribution of a photographically useful reagent, which reagent may be, for example, a photographically active reagent.

Abstract: A novel silver halide photographic element which contains a nondiffusible complex capable of releasing a diffusible, photographically useful material is disclosed.Said nondiffusible complex becomes active for ligand exchange upon reduction under alkalin conditions to release a diffusible, photographically useful material, said complex being represented by the following formula: ##STR1## wherein La is a quadridentate ligand group; Lb is a didentate ligand group; BALL is a ballast group; PHOTO is a photographically useful material group; Y is a counter ion; and r is the number of counter ions necessary for neutralizing the electric charge on the CO(III) complex.

Abstract: A redox release compound that is capable upon oxidation of releasing a silver ion complexing heterocyclic thio moiety enables reduction of the concentration of silver required in a photographic silver halide material comprising a combination of (i) photographic silver halide capable of forming a surface latent image, and (ii) a photographic silver halide capable of forming an internal latent image. The silver halide capable of forming an internal latent image preferably has lower photosensitivity than the silver halide capable of forming a surface latent image. The redox release compound preferably comprises a silver ion complexing 1,2,4-triazolium-3-thio moiety. An image is developed in such an exposed photographic silver halide element by means of a surface type silver halide developer.