Abstract: A process for producing a heat-developable photosensitive material containing fine photosensitive silver halide particles having a uniform particle form and particle size, said silver halide being prepared by reacting a silver salt of an organic fatty acid stoichiometrically with an inorganic or organic halogen compound.

Abstract: The invention relates to a photosensitive composition for direct positive color photography. The photosensitive composition comprises a binder containing a plurality of grains of a semiconductor material, each grain having adsorbed on its surface one of three different complexes of spiropyran with a metal salt, each complex being sensitive to a different wavelength of light, a cross-linkable polymer and a free radical initiator. The photographic composition provides a non-silver photographic process based on the photo-decomposition of the metal-spiropyran complex absorbed on the grains of semiconductor material.

Abstract: A lith-type silver halide photographic material comprising a tetrahydro-1,3,5-triazine-2-thione derivative and a polyalkylene oxide derivative.

Abstract: A negative silver halide photographic light-sensitive material is provided, having a silver halide emulsion layer, which layer comprises silver haloiodide grains prepared in the presence of an iridium salt in an amount of 1.times.10.sup.-8 to 1.times.10.sup.-5 mole per one mole of silver, wherein the silver iodide content in the surface part of said grain is larger than the average silver iodide content in said grain, and additionally containing in said emulsion layer or in some other hydrophilic colloid layer, a compound of formula (I):R.sub.1 --NHNH--CHO (I)wherein R.sub.1 represents an aliphatic group or an aromatic group. Said photographic light-sensitive material is, after being exposed imagewise, developed with a developer containing 0.15 mole/l or more sulfite ion and having a pH value of 9.5-12.3, to form negative images having ultra-high contrast.

Abstract: The present invention relates to a sublimation transfer system color hard copy printing paper particularly to prevent effectively the printing paper from being adhered by melt with a dye carrier ribbon when a color hard copying is carried out, transfer dye satisfactorily and present excellent color. To this end, the sublimation transfer system color hard copy printing paper of the present invention has formed, on the surface of a base material, a layer formed of thermo-plastic resin having a transferring property relative to a dispersing dye and a compound having two or more radically polymerizable unsaturated double bonds in one molecule and the sublimation dye is transferred on this resin layer to thereby present color.

Abstract: A method of thermal imaging is provided which comprises heating imagewise a layer of a colored di- or triarylmethane compound possessing within its di- or triarylmethane structure an aryl group substituted in the ortho-position to the meso carbon atom with a group comprising a thermally unstable urea moiety which fragments upon heating to provide a new group that bonds to the meso carbon atom whereby the di- or triarylmethane compound is rendered ring-closed and colorless in an imagewise pattern corresponding to said imagewise heating.

Abstract: A thermal imaging method is provided which comprises heating imagewise a di- or triarylmethane compound possessing within its di- or triarylmethane structure an aryl group substituted in the ortho position to the meso carbon atom with a moiety ring-closed on the meso carbon atom directly through a nitrogen atom, which nitrogen atom is also bound to a group with a masked acyl substituent that undergoes fragmentation upon heating to liberate the acyl group for effecting intramolecular acylation of said nitrogen atom to form a new group in the ortho position whereby the di- or triarylmethane compound is rendered colored in an imagewise pattern corresponding to said imagewise heating.

Abstract: A light-sensitive silver halide photographic material having silver halide emulsion layers on a support, wherein at least one layer of said silver halide emulsion layers contains surface latent image type mono-dispersed silver halide grains, and 50% or more of the silver halide grains contained in said at least one silver halide emulsion layer are regular surface latent image type mono-dispersed silver halide grains of tetradecahedral crystals whose external surfaces have crystal faces with Miller indices (100) and (111), the area ratio of said (100) face and said (111) face satisfying the relation represented by the correlation formula (I) shown below:correlation formula (I): ##EQU1## wherein K is the ratio between the intensities of respective diffraction lines attributable to the (200) face and the (222) face measured in X-ray diffraction analysis as set forth in the following formula ##EQU2##

Abstract: A direct positive silver halide photographic light-sensitive material is described containing a weak electron donative, adsorptive compound represented by formula (I) or (II) effective for depressing formation of a re-reversed negative image, which is not a spectral sensitizing agent for silver halide or a nucleating agent:D--L--X (I)D--X (II)whereinD represents electron donative atoms comprising an aromatic ring or hereto ring, which is unsubstituted or substituted;L represents a linking group containing at least one of C, N, S and O and an atom or atoms necessary for cutting a .pi.-conjunction system; andX represents a group which is adsorptive with respect to silver halide and contains at least one of C, N, S, O and Se.

Abstract: A silver halide photographic emulsion having a high spectral-sensitivity in a red-color wavelength range, especially within a wavelength range of from 600 nm to 690 nm, is disclosed, which contains one or more sensitizing dyes represented by formula (I) ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 each represents an alkyl group, a substituted alkyl group, or an alkenyl group;V.sub.1, V.sub.2, V.sub.3, and V.sub.4 each represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an acyl group, an acyloxy group, an alkoxycarbonyl group, a carboxyl group, an alkoxysulfonyl group, a cyano group, or a trifluoromethyl group;Q represents an alkyl group or an aralkyl group;X.sup..crclbar. represents an anion; andm is 1 or 2, provided that when the dye forms an internal salt, m is 1.

Abstract: A heat developable light-sensitive material containing a novel base precursor (I), which is stable during storage and rapidly decomposes to release a basic component upon heating higher than a certain temperature, has excellent storability and provides an image having a good image quality, i.e., a low fog density and a high image density within a short period of developing time.

Abstract: The present invention relates to an optical information recording medium comprising a recording layer applied directly on a substrate or applied on a substrate by intervening an underlayer therebetween, and further comprising a protective layer on said recording layer if necessary, characterized in that said recording layer contains at least one of the compounds expressed by the following general formula (I) or (II): ##STR1## (wherein in the above formulas, X.sub.1 to X.sub.3 represent O, S or Se; A.sup.- represents an anion; l, m or n represents 0 or 1; R.sub.4 represents a substituted or non-substituted aryl group or heterocyclic group; R.sub.3, R.sub.5, R.sub.6, R.sub.9, R.sub.10 and R.sub.11 represent hydrogen or an alkyl group; R.sub.1, R.sub.2, R.sub.7, R.sub.8, R.sub.12, and R.sub.13 represent hydrogen or a substituted or non-substituted alkyl, aryl or styryl group; Z.sub.1, Z.sub.3 and Z.sub.

Abstract: A heat developable photosensitive material having on a support, a light-sensitive layer containing a light-sensitive silver halide, silver salt grains having a dissolution retarder adsorbed thereto, a reducing agent, and a binder. This material can provide high image density and low fog density and has excellent keeping quality.

Abstract: A heat-developable photographic material having improved preservability, which comprises a support having thereon at least one heat-developable photographic layer, said photographic material containing a dye represented by formula (I) ##STR1## wherein n and m each represents 0, 1, 2 or 3;p and q each represents 0 or 1;L represents a methine group or a substituted methine group;R.sub.1 and R.sub.2 are same or different and each represents an unsubstituted or substituted alkyl group;R.sub.3 and R.sub.4 are same or different and each represents a hydrogen atom, an alkyl group, an alkoxy group, a hydroxyl group, an unsubstituted or substituted amino group or a halogen atom; or said R.sub.3 and R.sub.4 form a condensed 6-membered ring;Z and Z' are same or different and each represents a non-metallic atomic group necessary for forming a substituted or unsubstituted 5-membered or 6-membered ring, or substituted or unsubstituted 5-membered or 6-membered ring which is condensed with another ring;X.sup..crclbar.

Abstract: A silver halide photographic material comprising a support and at least two silver halide emulsion layers on one or both sides of the support, wherein at least one of silver halide emulsion layers contains a polymer having a repeating unit represented by the general formula (I) and/or dextran: ##STR1## wherein R.sup.1 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R.sup.2 and R.sup.3, which may be the same or different, and are each a hydrogen atom, or a group having 10 or less carbon atoms and selected from the group consisting of a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted aralkyl group, and R.sup.2 and R.sup.3 may combine together with the nitrogen atom to which they are attached to form a nitrogen-containing heterocyclic ring; L is an (m+1)-valent connecting group; n is 0 or 1; and m is 1 or 2.

Abstract: Disclosed herein is an optical recording medium which includes a recording layer composed of (a) an organometallic complex having an absorption maximum in the wavelength range of 600-1200 nm, (b) a resinous binder and (c) a sensitizer capable of generating radicals upon exposure to ultraviolet rays. The recording of information on the recording layer is effected with ease by exposure to ultraviolet rays. The reproduction of recorded information is effected by a laser beam having an oscillatory wavelength in the visible or near infrared wavelength range.

Abstract: An optical recording method which comprises providing a recording layer containing a recording susbstance that has an absorption maximum in the visible and near infrared wavelength region of 600 to 1,200 nm and loses or diminishes its power to absorb visible or near infrared radiation in the aforesaid wavelength region upon exposure to ultraviolet radiation, X-rays, an electron beam or an ion beam, and irradiating desired locations of the recording layer with ultraviolet radiation, X-rays, an electron beam or ion beam to form a pattern based on the presence or absence, or variation in strength, of the power to absorb visible or near infrared radiation in the aforesaid wavelength region so as to record information in the recording layer; a method for reading optically recorded information which comprises illuminating a pattern formed as described above with laser light having a wavelength in the aforesaid visible and near infrared region and detecting the presence or absence, or variation in intensity, of abso

Abstract: Industrial radiographic systems having low grainines and high information density may be constructed with intensifying screens sandwiching radiation sensitive elements having emulsions wherein the average size of the silver halide grains is less than 0.4 micrometers.

Abstract: The invention relates to a multilayered image receptive film developed in distinguishable colors by kinetic energy imparted by radiant beam exposure which comprises (a) a first imaging layer composed of an aliphatic, polymeric binder containing from about 40 wt. % to about 70 wt. % of labile halogen, said binder capable of dehydrohalogenation at address points of radiant energy exposure and having dispersed therein a first polyphenylmethane compound capable of forming a first halide salt dye upon generation of hydrogen halide from said binder; (b) a second imaging layer similar to said first imaging layer and contiguously disposed below said first imaging layer, containing a second and distinct polyphenylmethane compound capable of forming a halide salt dye of a color distinguishable from that of said first halide salt dye and (c) a conductive support for layers (a) and (b).

Abstract: An image receptive film comprising a surface layer containing a photosensitive polyacetylenic compound having at least two acetylenic linkages in a conjugated system is subjected to a plurality of radiant energy exposures each limited to a divisible portion of the image to be transmitted and at least each of 2 exposures effected at a distinctive dosage level, to develop exposed discrete portions in its respective divided portion to a characteristic color distinguishable from that developed in the surface layer by any other exposure at a different dosage level.