Abstract: A photochemical reactor element containing microcapsulated TiO2 photocatalyst particles dispersed in a polysiloxane matrix is disclosed. The polysiloxane matrix has an oxygen gas permeability not less than 1×10−14 mol·m·m−2·s−1·Pa−1. The photochemical reactor element is produced by dispersing the microcapsulated or naked TiO2 photocatalyst particles in a hydrolyzate-polycondensate sol of a trialkoxysilane or a mixture thereof with a tetra- and/or dialkoxysilane and then shaping the dispersion into the element. The naked TiO2 photocatalyst particles in the element are microcapsulated within a porous silica shell layer in situ by irradiating the element with UV radiation.

Abstract: A composition including a matrix comprised of particles comprised of a core resin and a shell resin thereover, wherein the core resin contains a covalently bonded photosensitive compound, and wherein the shell resin is the continuous phase of the matrix.

Abstract: An aqueous developable photosensitive element comprising a support and a photosensitive layer provided thereon, said layer containing (a) an elastomeric microgel binder having an elastomeric core which can be crosslinked and a thermoplastic noncrosslinked shell, (b) an initiator, (c) an ethylenically unsaturated monomer or oligomer and optionally (d) a basic compound capable of neutralizing the acidic functionality and method of use to make an aqueous developable flexographic printing plate is described.

Abstract: A process for producing a toner has the steps of, polymerizing a polymerizable monomer composition containing at least a polymerizable monomer and a colorant, in an aqueous dispersion medium to form colored polymer particles, and thereafter washing the colored polymer particles, followed by dewatering to prepare wet colored polymer particles, subjecting the resultant wet colored polymer particles to substantial removal of the water held by the wet colored polymer particles, by means of a dryer making use of hot air to obtain toner particles, and drying the toner particles under reduced pressure by means of a vacuum dryer so that polymerizable monomers remaining in the toner particles come to be in a residue of 200 ppm or less.

Abstract: A printing apparatus of a photosensitive microcapsule type comprises a chassis, a cassette for storing printing paper containing photosensitive microcapsules, a printing paper feeding device for intermittently feeding the printing paper in a feeding direction, and a printing paper pickup device for feeding the printing paper from the cassette to a preselected location from which the printing paper is intermittently fed by the printing paper feeding device. A scan shaft is mounted on the chassis for undergoing rotation about a rotational axis extending generally perpendicular to the feeding direction of the printing paper. A first spiral groove is formed in the scan shaft along a clockwise direction and has opposite ends. A second spiral groove is formed in the scan shaft along a counterclockwise direction and has opposite ends each connected to a respective end of the first spiral groove so that the first and second spiral grooves form a loop.

Abstract: A thermal recording medium comprising a ultraviolet absorber precursor represented by formula (1-A) or an image forming compound changing hue and an acid, which is high in thermal sensitivity, recordable with such a low output laser that no ablation takes place even when a thermal heat mode image recording system using a laser is utilized, requiring no different receiving sheet, and excellent in keeping quality: wherein P represents a protecting group for a hydroxyl group which is deblocked by heating to 250° C. or less in the presence of an acid; R1 and R2, which may be the same or different, each represents a substitutable group; and 1 and m each represents an integer of 0 to 4.

Abstract: A polymerized toner of core-shell structure, comprising core particles composed of colored polymer particles which contain a compound having at least one >C═N+< structure in its molecule and a colorant, and a layer of a polymer having a glass transition temperature higher than that of a polymer component making up the core particles, said polymer layer covering each of the core particles, a production process thereof, an image forming process comprising using the polymerized toner, and an image forming apparatus containing the polymerized toner.

Abstract: An imaging system comprising a support having a layer of at least one set of photosensitive microcapsules on the surface thereof, wherein the microcapsules are sensitive to a distinct band of radiation and contain a complex of an infrared sensitive cationic dye and a boranyl anion. In a preferred embodiment, the photosensitive microcapsules include a first set of microcapsules containing a cyan color-forming agent, a second set of microcapsules containing a magenta color-forming agent, and a third set of microcapsules containing a yellow color-forming agent, wherein at least one of said first, second and third sets of microcapsules include an infrared sensitive dye borate compound as a photoinitiator. Optionally at least one other set may include a visible light sensitive dye borate compound or an ultraviolet initiator.

Abstract: A lithoprinting plate comprising a support and a recording layer which comprises a polyvalent metal ion and a hydrophilic binder polymer having a Lewis base portion containing nitrogen, oxygen or sulfur and which has an oleophilic image area and a hydrophilic non-image area which are printed in a thermal mode, wherein the hydrophilic binder polymer in the hydrophilic non-image area is three-dimensionally cross-linked by the interaction between the polyvalent metal ion and the Lewis base portion.

Abstract: The present invention provides a polymerizable printing ink. The ink includes a polar suspending medium in which a plurality of polymer microspheres are suspended. At least one surfactant is dissolved in the suspending medium, and a monomer is positioned in the ink such that polymerization of the monomer after the application of the ink to a substrate will hold the microspheres in fixed relations to one another. The microspheres have a chemically associated coloring agent to provide the ink with color. The ink may include a polymerization initiator, such as a photoinitiator, to cause the film to polymerize upon the application of a form of energy, such as ultraviolet light. The invention also provides methods for making and using the ink, and for adding a coloring agent to a plurality of polymer microspheres.

Abstract: A printing device according to the present invention includes a dye tank for containing a powdered vaporizable dye, an entrance section for liquefying the powdered vaporizable dye and a vaporizing section for radiating a laser light beam onto the liquefied dye transported to it by the entrance section for vaporizing the liquefied dye for thermal transcription of the vaporized dye onto a photographic paper. In this manner, printing may be made without employing an ink ribbon or a thermal head and hence the saving in power and the reduction in size and costs of the printing device may be achieved. Besides, the printing time may be shortened, while the size of the printing paper, may be set freely.A photographic paper according to the present invention includes a light absorbing layer between a receptor layer and a photographic paper base.

Abstract: A photosensitive material including a support having a layer of photosensitive microcapsules on the surface thereof, the photosensitive microcapsules including an internal phase containing a photosensitive composition and a color precursor wherein, upon image-wise exposing the photosensitive material and rupturing the microcapsules, the color precursor is image-wise released from the microcapsules to form a color image, the photosensitive material further including a hygroscopic polymer, is disclosed.

Abstract: A photosensitive recording medium used to transfer and form an image onto an image-receiving medium, comprises a base material and formed thereon a photosensitive layer having a photosensitive material and an image-forming material, where the photosensitive layer is set to have a luminous reflectance of from 2% to 20%.

Abstract: A silver halide light sensitive photographic material is disclosed, comprising a transparent support having thereon a silver halide emulsion layer, and the photographic material further having a color filter layer comprising picture elements comprised of a colored resin and randomly arranged.

Abstract: A photosensitive recording material comprises a support and microcapsules provided thereon, wherein the microcapsules comprises a photopolymerizable unsaturated group-containing compound and a phosphine compound represented by the following general formula: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 indicate a hydrogen atom, a C.sub.1 to C.sub.20 alkyl, aryl or aralkyl group, --OR.sup.4, or --SR.sup.4 where R.sup.4 indicates a hydrogen atom or a C.sub.1 to C.sub.20 alkyl, aryl or aralkyl group, and these may be substituted by a halogen atom or a C.sub.1 to C.sub.20 alkoxy, alkoxycarbonyl, acyloxy, alkanoyl, cyano, hydroxy or amino group.

Abstract: The present invention relates to a method for applying an image to a fabric, which comprises the steps of (i) hand ironing an imaged copier or printer transfer material having a support sheet and a transfer coating to a receptor element having valleys on the surface of the receptor element, (ii) peeling away the support sheet to obtain an imaged receptor element, (ii) placing a tack-free overlay sheet over the imaged receptor element, and (iv) pressing the overlay sheet by hand ironing to drive the coating into the valleys of the receptor element.

Abstract: The present invention relates to a method for applying an image to a fabric, which comprises the steps of (i) hand ironing an imaged copier or printer transfer material having a support sheet and a transfer coating to a receptor element having valleys on the surface of the receptor element, (ii) peeling away the support sheet to obtain an imaged receptor element, (ii) placing a tack-free overlay sheet over the imaged receptor element, and (iv) pressing the overlay sheet by hand ironing to drive the coating into the valleys of the receptor element.

Abstract: A photosensitive imaging system comprising a photosensitive material and a developer material, the photosensitive material including a support having a layer of photosensitive microcapsules on the surface thereof, said photosensitive microcapsules including an internal phase containing a photosensitive composition and a color precursor wherein, upon image-wise exposing said photosensitive material and rupturing said microcapsules, said color precursor image-wise reacts with said developer material to form a color image, said support being a high opacity laminate of a black or brown film laminated between a pair of white pigmented films; in one embodiment the black or brown film is a magnetic recording layer.

Abstract: An imaging system is provided wherein images are formed with good tonal qualities in a short time immediately after development process. Concretely, the imaging system of the invention comprises a print medium, wherein microcapsules encapsulate a color-forming material, a polymerization initiator and a developer, an irradiation box, which selectively exposes the print medium, a pressure-developing roller, and first and second post heaters. After the development using the pressure-developing roller, the print medium is heated by the first post heater on the condition that the heating time Y is longer than a second and shorter than approximately 1060 exp (-0.082X) seconds, wherein X is defined as the heating temperature (degrees). Further, the print medium is heated by the second post heater on the condition that the heating time Y is shorter than a second and longer than approximately 1060 exp (-0.082X) seconds.

Abstract: A process for producing a binder resin for a toner comprising the steps of (1) mixing a substantially solventless resin (A) and an emulsion of a resin (B) different from resin (A) with stirring and (2) evaporating water from the mixture of resin (A) and the emulsion of resin (B) simultaneously with or after the step (1) to obtain a substantially solventless resin composition.

Abstract: A thermal recording medium comprising a ultraviolet absorber precursor represented by formula (1-A) or an image forming compound changing hue and an acid, which is high in thermal sensitivity, recordable with such a low output laser that no ablation takes place even when a thermal heat mode image recording system using a laser is utilized, requiring no different receiving sheet, and excellent in keeping quality: ##STR1## wherein P represents a protecting group for a hydroxyl group which is deblocked by heating to 250.degree. C. or less in the presence of an acid; R.sup.1 and R.sup.2, which may be the same or different, each represents a substitutable group; and 1 and m each represents an integer of 0 to 4.

Abstract: Disclosed is a photo- and heat-sensitive recording material comprising a substrate and a photo- and heat-sensitive recording layer formed thereon containing a diazo compound and a coupler, wherein the coupler is a compound represented by the general formula (1) or the general formula (2): ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each independently a hydrogen atom or a substituent group; and R.sup.1 and R.sup.2 may join with each other to form a ring. The reaction between the coupler represented by the general formula (2) and a specific diazo compound produces a magenta colorant having very sharp absorption characteristics. In short, the present invention provides a photo- and heat-sensitive recording material which does not inhibit the fixing and which exhibits excellent color formation, color reproduction, and image durability. Further, the present invention provides a magenta colorant which exhibits excellent absorption characteristics.

Abstract: The invention relates to a silver halide photographic image forming process in which a developing agent incorporated into microvesicles is used. The developing agent is encapsulated in multilamellar microvesicles, and these microvesicles are then brought into contact with the exposed silver halides in the presence of an alkaline activator upon development. Application to the design of a simplified processing of silver halide photographic materials.

Abstract: An imaging medium comprises a substrate carrying a color-change layer. This color-change layer comprises two layers or phases comprising two color-forming reagents which react upon heating to cause a change in the color of the layer. The color-change layer is deactivated by exposure to actinic radiation such that after deactivation it no longer undergoes its thermal color-change. The color-change layer is detachable from the substrate by heating to a temperature lower than required to cause the color change, so that upon contact of the imaging medium with a receiving sheet each individual pixel of the color-change layer may be left attached to the substrate, transferred to the receiving sheet but left uncolored, or transferred to the receiving sheet and colored to a color level determined by the energy used in the associated thermal print head element.

Abstract: Heterogeneous photoinitiator in microparticle form, which consists of a finely divided substrate material to which identical or different photoinitiators are covalently bonded. The photoinitiators are suitable for the radiation-induced polymerization of photopolymerizable or photocrosslinkable monomers for the production of moldings, protective coats and relief images.

Abstract: A photosensitive recording medium has a structure wherein, on a light-transmitting base material, a photosensitive layer containing color image-forming photosensitive microcapsules having as materials encapsulated therein a colorant and a photosensitive material is formed and, on the photosensitive layer, an image-receiving layer is formed. The image-receiving layer has a function to cover up the photosensitive microcapsules in the fresh photosensitive recording method and, upon release of the encapsulated materials from the photosensitive microcapsules, a function to absorb the encapsulated material to form an image. The photosensitive recording medium enables formation of full-color images on the photosensitive recording medium itself, and can achieve a low running cost and also be used even in small-sized image-forming apparatus.

Abstract: A photosensitivematerial including a support having a layer of photosensitive microcapsules on the surface thereof, the photosensitive microcapsules including an internal phase containing a photosensitive composition and a color precursor wherein, upon image-wise exposing the photosensitive material and rupturing the microcapsules, the color precursor is image-wise released from the microcapsules to form a color image, the photosensitive material further including a superabsorbent polymer or hydrogel, is disclosed.

Abstract: A new digital printer media which allows to create images on both sides of a single sheet is proposed. The media is printed in a new Cycolor printer which utilizes two LED printer heads and one developer head/device. The film consists of the top and the bottom layers of capsules/developer coats on clear polyester (top and bottom) with the white polyester with adhesive on both sides as the separator. The color producing capsules/developer mixture is coated on clear polyester. The coated film is then laminated with white polyester containing adhesive on both sides. The top side of the white polyester remains protected by the removable liner. Thus created film is then used to laminate another layer of capsule/developer coated clear polyester. The double sided film is thus created. Following exposure from both sides will occur independently by a set of two LED heads. Developing pressure can be applied from one side. Two images can be formed at the same time on both sides of a single sheet.

Abstract: A photocurable composition comprises an unsaturated group-containing compound as a base material, a metal arene compound as a photopolymerization initiator and an aniline compound as a photosensitizer. As the photosensitizer aniline compound, any one or both of 2,6-diisopropyl-N,N-dimethylaniline and 2,4,6,N,N-pentamethylaniline is/are used.

Abstract: Disclosed is a light and heat sensitive recording material which permits recording using infrared laser light, requires no developing solution or the like, causes no unnecessary generation of waste, and is capable of forming completely dry, black-and-white monochrome or color, and clear images with high contrast. The light and heat sensitive recording material comprises a light and heat sensitive recording layer disposed on a support member, comprising the light and heat sensitive recording layer. It includes an electron donating colorless dye contained in heat-responsive microcapsules; and an electron accepting compound, a polymerizable monomer which is cured by irradiation with light, and an organic borate salt or an organic borate salt of a cationic coloring material which develops functions as a photo polymerizing initiator when irradiated with light which are arranged outside the heat responsive microcapsules.

Abstract: A heat-sensitive recording material having formed on a support a heat-sensitive recording layer containing a diazonium salt and a coupling component, wherein the diazonium salt is a compound represented by the following formula (1): ##STR1## wherein R.sup.1 represents an alkyl group or an aryl group; R.sup.2, R.sup.3, R.sup.4 and R.sup.5 each independently represents a hydrogen atom or an alkyl group, at least one of R.sup.2, R.sup.3, R.sup.4, and R.sup.5 represents an alkyl group, and R.sup.2 and R.sup.3, or R.sup.4 and R.sup.5, or R.sup.1 and R.sup.3, or R.sup.1 and R.sup.4, may combine with each other to form a ring; and X.sup.- represents an anion.

Abstract: A rewritable thermal recording medium of this invention uses a recording material which reversibly changes between an equilibrium state and a quasi-equilibrium state different in color condition from the equilibrium state when a predetermined heat treatment is performed. This rewritable thermal recording medium includes a substrate and a recording layer formed on the substrate. The recording layer has a first region containing a first recording material which takes on lighter color in quasi-equilibrium than in equilibrium, and a second region containing a second recording material which takes on darker color in quasi-equilibrium than in equilibrium.

Abstract: The speed at which a thermosensitive recording medium is scanned with a laser beam is selected to be 5 m/s or higher to increase the temperature of a thermosensitive layer of the thermosensitive recording medium for recording a gradation image thereon with high sensitivity. A sharp temperature gradient is produced along the thickness of the thermosensitive layer, so that a density gradient along the thickness of the thermosensitive layer is developed, therefore, a high-quality image can be recorded without producing any density irregularities caused by thickness irregularities of the thermosensitive layer.

Abstract: A thermal recording material comprising a support having provided thereon a thermal recording layer containing a diazonium salt and a coupling component. The diazonium salt is a compound represented by the following general formula (1):General Formula (1) ##STR1## wherein T and U each independently represents a hydrogen atom, a halogen atom, an alkyl group or an acylamino group; V represents a hydrogen atom, a halogen atom, an alkyl group or OR.sup.3 ; R.sup.1, R.sup.2 and R.sup.3 each independently represents an alkyl group or an aryl group; and X.sup.- represents an anion. The thermal recording material has excellent stock storage stability and provides fast color-developed images having an extremely high developed color density.

Abstract: A method of storing and a kit containing a full color dry image-forming material which does not form a muddy color, even after being stored over a long period of time, is provided by;1) A method of storing and a kit containing a dry image-forming material comprising a support and a layer provided thereon containing microcapsules containing at least a photo-curable compound, a photo initiator and a color precursor in the internal phase. The material contains a color-developer in the layer containing the microcapsule or a layer adjacent thereto and the dry image-forming material is packed together with a humidity-controlling material; or,2) The method of storing and kit as above, wherein the dry image-forming material and a humidity-controlling material are stored with a low moisture-permeable film.

Abstract: A thermographic material is disclosed which comprises a support and provided thereon, a recording layer containing a photolytic free radical generating agent capable of providing a free radical on absorption of light, a dye decolored by the free radical, and an anti-decolorizing agent, the photolytic free radical generating agent and dye being contained in a microcapsule in the recording layer, and the anti-decolorizing agent being present outside the microcapsule in the recording layer, wherein an image is formed by imagewise heating the thermographic material to mix the anti-decolorizing agent with the photolytic free radical generating agent and the dye to form a latent image, and then exposing the heated material to light which the photolytic free radical generating agent absorbs, so that the dye at the latent image portions is not decolored and the dye at portions other than the latent image portions is decolored.

Abstract: A method of forming an image comprising imagewise-exposing a thermal recording element to heat, the element comprising a support having thereon a thermally-sensitive layer comprising particles containing a colorant, the particles having a particle size between about 1 and about 25 .mu.m suspended in a matrix, the layer having an optical density no higher than about 0.5, the heating thereby causing the colorant to spread out from the particles into the matrix, thus increasing the optical density in the imagewise-exposed areas.

Abstract: The invention relates to a silver halide photographic image forming process in which a developing agent incorporated into microvesicles is used. The developing agent is encapsulated in multilamellar microvesicles, and these microvesicles are then brought into contact with the exposed silver halides in the presence of an alkaline activator upon development. Application to the design of a simplified processing of silver halide photographic materials.

Abstract: Disclosed herein are a polymerized toner of core-shell structure, comprising core particles composed of colored polymer particles having a volume average particle diameter (dv) of 0.5-20 .mu.m and a ratio (dv/dp) of the volume average particle diameter (dv) to a number average particle diameter (dp) of at most 1.7, and shell which is formed of a polymer layer having an average film thickness of 0.001-0.1 .mu.m and covers each of the core particles, and a production process thereof.

Abstract: A photosensitive recording medium comprising a base material and formed thereon a photosensitive layer containing at least yellow color-forming particles containing a first photosensitive component having a maximum hardening sensitivity to light with wavelength L1, magenta color-forming particles containing a second photosensitive component having a maximum hardening sensitivity to light with wavelength L2 and cyan color-forming particles containing a third photosensitive component having a maximum hardening sensitivity to light with wavelength L3. All the wavelengths L1, L2 and L3 are wavelengths longer than 500 nm.

Abstract: A process for producing a toner for development of electrostatic latent images, which is composed of colored polymer particles and has a low fixing temperature, good permeability through OHP and excellent shelf stability, by subjecting a monomer composition containing at least a polymerizable monomer and a colorant to suspension polymerization in an aqueous dispersion medium containing a dispersing agent comprises at least two steps of:(1) the first step of subjecting a monomer composition for core component containing at least one monomer for core component, which is capable of forming a polymer having a glass transition temperature not higher than 80.degree. C.

Abstract: A composition including a matrix comprised of particles comprised of a core resin and a shell resin thereover, wherein the core resin contains a covalently bonded photosensitive compound, and wherein the shell resin is the continuous phase of the matrix.

Abstract: The present invention relates to a method for applying an image to a fabric, which comprises the steps of (i) hand ironing an imaged copier or printer transfer material having a support sheet and a transfer coating to a receptor element having valleys on the surface of the receptor element, (ii) peeling away the support sheet to obtain an imaged receptor element, (ii) placing a tack-free overlay sheet over the imaged receptor element, and (iv) pressing the overlay sheet by hand ironing to drive the coating into the valleys of the receptor element.

Abstract: A method of image formation which comprises (a) providing a radiation sensitive plate comprising a substrate and a coating containing a heat softenable disperse phase, an aqueous soluble or swellable continuous phase and a radiation absorbing substance, (b) image-wise exposing the plate to at least partially coalesce the particles of the disperse phase in the image areas, (c) developing the image-wise exposed plate to remove the coating in the unexposed areas, and (d) heating the developed plate or subjecting it to irradiation to effect insolubilization of the image. Good quality images of high durability are obtained.

Abstract: A heat development type duplicating material having a recording layer which is formed on a support. The recording layer comprises a photosensitive diazo compound and a coupler that reacts with the diazo compound to develop color. Furthermore, the duplicating material contains an ascorbic acid derivative. The heat development type duplicating material generates little stain in background areas, exhibits satisfactory storage stability, and provides a high image density.

Abstract: A method of producing a three-dimensional object having selected elements which are colored differently than other elements of the object comprising the steps of:(a) providing a film of a photohardenable composition containing a photoresponsive agent,(b) radiating the film in a cross-sectional pattern of the object to be formed,(c) selectively irradiating one or more portions of the cross-sectional pattern corresponding to the selected elements which are desired to be colored differently with radiation which activates the photoresponsive agent, the photoresponsive agent thereby producing color in or removing color from the selected irradiated portions of the cross-sectional pattern,(d) repeating steps a, b, and c to form successive adjacent cross-sectional pattern of the object, and(e) integrating the cross-sectional patterns together to provide the three-dimensional object, wherein the curing and coloring steps are conducted using actinic radiation.

Abstract: A diazonium salt for a color-forming layer of a thermosensitive recording medium, having formula (1): ##STR1## wherein R is an alkyl group having four carbon atoms which is selected from the group consisting of n-butyl, t-butyl, and sec-butyl, and X.sup.- is selected from the group consisting of hexafluorophosphate ion PF.sub.6.sup.-, tetrafluoroborate ion BF.sub.4.sup.- and tetraphenylborate ion (C.sub.6 H.sub.5).sub.4 B.sup.-. In a first embodiment, a thermosensitive recording medium has a color-forming layer which includes a diazonium salt as described above, a basic compound and a coupler. In a second embodiment, a thermosensitive recording medium has a color-forming layer which includes: a diazonium salt, a basic compound, and a coupler, wherein the diazonium salt has a formula (2): ##STR2## where R.sup.1 and R.sup.2 are alkyl groups each having one or more carbon atoms, and X.sup.- is selected from the group consisting of hexafluorophosphate ion PF.sub.6.sup.-, tetrafluoroborate ion BF.sub.4.sup.

Abstract: A heat-sensitive recording material having a support and a heat-sensitive recording layer provided thereon. The heat-sensitive recording layer contains a diazonium salt compound and a coupler which reacts with the diazonium salt compound upon heating to form a color. The heat-sensitive recording layer contains a compound of the following formula (I): ##STR1## wherein R represents a member selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, and an aryl group; X represents a member selected from the group consisting of --COOR.sup.1, --OCOR.sup.--1, --CONR.sup.1 R.sup.2, and --NR.sup.2 COR.sup.1 ; R.sup.1 represents an alkyl group or an aryl group, R.sup.2 represents a member selected from the group consisting of a hydrogen atom, an alkyl group, and an aryl group; n represents an integer from 1 to 5.

Abstract: A radiation sensitive material comprises particles including a water-insoluble heat-softenable core surrounded by a shell which is soluble or swellable in aqueous medium. The material also includes a radiation sensitive component which, on exposure to radiation, causes the solubility characteristics of the material to change. The material may be positive- or negative-working and may be coated onto a substrate from aqueous media to form a radiation sensitive plate which, after image-wise exposure, can be developed in aqueous media and then heated to cause the particles to coalesce and form a durable printing image.

Abstract: Disclosed is a heat-sensitive recording material comprising a substrate having thereon a heat-sensitive recording layer containing a diazonium salt compound and a coupler, pyrrolo?1,2-a! pyrimidine compound, as the coupler, being represented by the following general formula (1): ##STR1## wherein R.sup.1 to R.sup.4 each represents a hydrogen atom, a halogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a substituted carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an alkoxy group, an aryloxy group, an alkylthio group, or an arylthio group.The diazo-type heat-sensitive recording material, which develops a violet to cyan color, has excellent image stability and image fixing characteristics.