Abstract: A thermal transfer material includes a support. A release layer is overlaid on the support. A coloring transfer layer is overlaid on the release layer, has thermoplasticity, and is colorable by being exposed and then pressurized. In a printer for use with the thermal transfer material, an image is formed by exposing the coloring transfer layer. The coloring transfer layer is placed on image receiving material after the image is formed. The thermal transfer material is heated and pressurized while the coloring transfer layer is placed on, so as to color the image and transfer the coloring transfer layer to the image receiving material.

Abstract: A heat mode recording element is disclosed comprising a metal recording layer, preferably a bismuth layer, and a layer containing a roughening agent underneath the metal layer. An image is formed by exposure with intense laser light and the presence of the roughening agent reduces or eliminates interference patterns. In an alternative embodiment a roughened support is used instead of a layer containing a roughening agent.

Abstract: A process for generation of acid uses a medium comprising a first acid-generating component capable of generating a first acid, and a secondary acid generator, this secondary acid generator being capable of thermal decomposition to form a secondary acid, the thermal decomposition of the secondary acid generator being catalyzed by the first acid. At least part of the medium is exposed to so as to cause formation of the first acid from the first acid-generating component; and the medium is then heated to cause, in the exposed part of the medium, acid-catalyzed thermal decomposition of the secondary acid generator and formation of the secondary acid.

Abstract: A silver halide color photographic material comprising a support having provided thereon at least one hydrophilic colloidal layer containing at least one color-developing agent represented by general formula (1) and at least one coupler represented by general formula (2): wherein C&agr; represents a carbon atom, Z represents a carbamoyl group, an acyl group, an alkoxycarbonyl group or an aryloxycarbonyl group, and Q represents an atomic group forming an unsaturated ring together with C&agr;. wherein C&bgr; represents a carbon atom, EWG represents a cyano group, a carbamoyl group or an alkoxycarbonyl group, LG represents a group which is released by a coupling reaction with an oxidation product of a developing agent, and M represents an atomic group forming a 5-membered aromatic heterocycle together with C&bgr;.

Abstract: An image formation method for forming a color image by imagewise exposing a color negative type silver halide photographic material comprising a transparent support having provided thereon at least three kinds of light-sensitive layers, followed by development processing at a temperature of 50° C. or more, which comprises the steps of reading with an imaging apparatus an image obtained from the color negative type silver halide photographic material whose sensitivity and gradient satisfy the following relationship, applying digital image processing thereto, and then, obtaining output signals of three or more colors: 1.0≦(log10S)·&ggr;≦2.5 S≧800 wherein S represents an ISO sensitivity, and &ggr; represents an average gradient of the three kinds of light-sensitive layers, thereby inviting no failure in shooting due to insufficient exposure in a compact camera or a film with lens, and forming a color image of high quality.

Abstract: A method for making a lithographic printing master is disclosed. The method comprises a step of providing a hydrophilic cylindrical surface, e.g. an aluminium plate mounted on the plate cylinder of a printing press, with an image recording composition by transfer from a donor material. The donor material comprises a support and a transfer layer which comprises hydrophobic thermoplastic polymer particles dispersed in a hydrophilic binder and a compound capable of converting light to heat. The transfer is obtained by friction between the donor layer and the cylindrical surface and/or by moistening the cylindrical surface with an aqueous liquid. The method is especially suited for on-press coating and on-press imaging in computer-to-press procedures.

Abstract: A (photo) thermographic recording material comprising a substantially colourless support and a (photo-addressable) thermosensitive element containing a substantially light-insensitive organic silver salt, an organic reducing agent for the substantially light-insensitive organic silver salt in thermal working relationship therewith (, photosensitive silver halide is catalytic association with the substantially light-insensitive organic silver salt) and a binder, characterized in that a blue pigment or dye having a maximum absorption wavelength of from 550 to 700 nm is present in the thermosensitive element and/or any other layer on either side of the support which provides a background for viewing in transmission images produced with the (photo) thermographic recording material; and a (photo) thermographic recording process therefor.

Abstract: A gradation image is recorded on a heat-sensitive recording material, which converts light energy applied thereto to heat energy and forms a color in a density according to a quantity of the heat energy by scanning the heat-sensitive recording material in a main scanning direction with a laser beam modulated according to the gradation of an image to be recorded while conveying the heat-sensitive recording material in a sub-scanning direction relative to the laser beam. The heat-sensitive recording material includes a support and a heat-sensitive layer mainly formed of organic material which is formed on the support, and the diameter d of the laser beam as measured in the sub-scanning direction, the recording intervals D in the sub-scanning direction and the sub-scanning frequency f are set to satisfy the formulae:1.66.ltoreq.d/D.ltoreq.1.98+10.sup.4.25 .multidot.f.sup.-1.57 and200 Hz.ltoreq.f.ltoreq.900 Hz.

Abstract: A process for generation of acid uses a medium comprising a first acid-generating component capable of generating a first acid, and a secondary acid generator, this secondary acid generator being capable of thermal decomposition to form a secondary acid, the thermal decomposition of the secondary acid generator being catalyzed by the first acid. At least part of the medium is exposed to so as to cause formation of the first acid from the first acid-generating component; and the medium is then heated to cause, in the exposed part of the medium, acid-catalyzed thermal decomposition of the secondary acid generator and formation of the secondary acid.

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: There is disclosed a silver halide photographic light-sensitive material that contains at least one color-developing agent of formula (I) and at least one dye-forming coupler of formula (II) contained in one or more photographic constitutional layers provided on a base: ##STR1## in formula (I), Z is a carbamoyl group or the like, and Q represents a group of atoms required to form an unsaturated ring together with the C, and in formula (II), M represents a coupler component capable of causing coupling reaction at the site where G is bonded with the oxidized color-developing agent, G is a hydrogen atom or a coupling split-off group, Y.sup.1 and Y.sup.2 each represent a group having a dissociation group, whose pKa is 1 or more but 12 or less, and n and m are each an integer of 0 to 3, provided that n+m.gtoreq.1. There is also disclosed an image-forming method using the light-sensitive material.

Abstract: A process for producing an image uses an imaging medium comprising an acid-generating layer or phase comprising a mixture of a superacid precursor, a sensitizing dye and a secondary acid generator, and a color-change layer comprising an image dye. The sensitizing dye has first and second forms, the first form having substantially greater substantial absorption in a first wavelength range than the second form. The superacid precursor is not capable, in the absence of the first form of the sensitizing dye, of being decomposed by radiation in the first wavelength range. The secondary acid generator is capable of thermal decomposition, catalyzed by superacid, to form a secondary acid. While at least part of the sensitizing dye is in its first form, the medium is imagewise exposed to radiation in the first wavelength range, thereby causing, in the exposed areas of the acid-generating layer, the formation of superacid.

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: According to the present invention there is provided a photothermographic material comprising on a support a photo-addressable thermally developable element containing a substantially light-insensitive organic heavy-metal salt, photosensitive silver halide in catalytic association with said substantially light-insensitive organic heavy-metal salt, a reductor for said substantially light-insensitive organic heavy-metal salt and a binder, said photothermographic material having on the same side of the support as said photo-addressable thermally developable element an outermost layer having two phases at least one of which being a dispersion phase of thermoplastic particles, characterized in that said two phases exhibit different affinities for at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink.

Abstract: A recording process comprising the steps of: information-wise exposing to radiation a photosensitive thermally developable photographic material, thereby producing a latent image; and heating the photosensitive thermally developable photographic material, characterized in that the photosensitive thermally developable photographic material is on one and the same holding or guiding means during both the information-wise exposure step and the heating step; and the information-wise exposure step is carried out during the heating step; and a method of increasing the photosensitivity of a photosensitive thermally developable photographic material.

Abstract: A camera-speed color photothermographic imaging method is disclosed. A photothermographic film is employed that contains a photographically responsive, thermally developable panchromatically sensitized emulsion layer unit capable of concurrently forming silver and dye image densities. The emulsion layer unit is exposed in three separate image capture areas to blue, green or red light received from the photographic subject to create latent images of blue, green and red light exposure. The photothermographic element is thermally processed to produce images of the same hue in each of the three separate image capture areas. The images of blue, green and red light exposures are then converted into a corresponding additive or subtractive primary hue, and integrated to provide a positive or negative color image of the photographic subject.

Abstract: The present invention relates to an infra-red laser sensitive thermographic material and to a process for forming a heat mode image using such a material.

Abstract: A method for generating on a lithographic printing plate a screened reproduction of a contone image, comprising the steps of: (1) transporting a thermo-sensitive imaging element through an exposure area; (2) scanwise exposing the thermo-sensitive imaging element according to screened data representative for tones of a contone image with a set (s) of radiation beams (b) as the thermo-sensitive imaging element is transported through the exposure area, characterized in that at any given moment (ta+.DELTA.t) during the exposure at least two radiation beams (bi,bj) of the set of radiation beams impinge on different microdots (ma, ma+.DELTA.m) of a scanline (1a) on the imaging element, so that by completion of the exposure step each effective microdot of the scanline has been impinged by all effective radiation beams of the set.

Abstract: A process for generation of acid uses a medium comprising a first acid-generating component capable of generating a first acid, and a secondary acid generator, this secondary acid generator being capable of thermal decomposition to form a secondary acid, the thermal decomposition of the secondary acid generator being catalyzed by the first acid. At least part of the medium is exposed to so as to cause formation of the first acid from the first acid-generating component; and the medium is then heated to cause, in the exposed part of the medium, acid-catalyzed thermal decomposition of the secondary acid generator and formation of the secondary acid.

Abstract: There is disclosed novel color-developing agents of the formula (I). There is also disclosed silver halide photographic light-sensitive materials and image-forming methods, using the color-developing agent. The color-developing agent is excellent in color-forming property, and the image obtained from the color-developing agent is good in stability of hue and image. ##STR1## wherein Z.sup.1 represents an acyl group, a carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, or a carbonimidoyl group, Q.sup.1 represents a group of atoms required to form a 5- or 6-membered aromatic ring together with the C, Q.sup.2 represents a heterocyclic residue, Y.sup.1 represents a group capable of substitution onto the aromatic ring, m is 1 or 2, and n is an integer of 0 to 3.

Abstract: A process for exposing a silver halide-containing photothermographic element with radiation to produce a latent image comprising a) providing a source of radiation which emits a beam of radiation to produce a spot having at least one dimension of height or length of less than 600 micrometers at a target site, b) providing at said target site a photothermographic silver halide element sensitive to radiation emitted by said radiation source, c) emitting radiation a first time in an imagewise distribution from said radiation source so that said radiation strikes said element as spots having at least one dimension of length or width which is less than 250 micrometers, and d) then emitting radiation a second time in an imagewise distributed manner so that at least some spots from radiation emitted said second time overlap spots where said first emitted radiation struck said photothermographic element.

Abstract: An image formation process comprising image exposing a photosensitive element which contains at least a photosensitive silver halide, a binder and a dye donating compound which forms or releases a diffusive dye corresponding or inversely corresponding to an exposure amount, and transferring the diffusive dye formed or released to a dye fixing element by heat development in the presence of a base and/or a precursor thereof, wherein the process further comprises the step of feeding water to said photosensitive element after image exposure, and the photosensitive element is maintained at a temperature of 40.degree. to 90.degree. on undergoing exposure, whereby photographic performance of the heat development photosensitive material exhibits good stability to changes in ambient temperature on undergoing exposure.

Abstract: Provided are a processing material used for forming images on a heat-developable photosensitive material by heating the processing material and the photosensitive material in a condition that they are brought into face-to-face contact, with the processing material comprising a long web support, preferably having a thickness of from 4 to 40 .mu.m, provided thereon a processing layer, preferably comprising a base or a precursor of bases; and a method of forming images on a heat-developable photosensitive material, which comprises a step of supplying a fountain water to the photosensitive material, a step of bringing the dampened photosensitive material into face-to-face contact with the aforesaid processing material and a step of applying heat thereto.

Abstract: Certain squaric acid derivatives are useful for the thermochemical generation of acid. The squaric acid derivatives may be used in imaging media in conjunction with acid-sensitive materials which undergo a color change when contacted by the acid generated from the squaric acid derivatives. Preferably, the acid-sensitive materials undergo an irreversible color change, so that the image can be fixed by neutralizing all the acid generated with excess base, thereby preventing further color change in the image during long term storage.

Abstract: A method for producing a printing plate which involves forming an image on the surface of a sheet having open cells by selectively applying a thermal exposure to the surface of the sheet. The sheet is a thermoplastic resin preferably having melting point between about 50.degree. to 150.degree. C. The resulting printing plate has a planar surface with no relief sections; instead there are porous and nonporous sections, with the porous sections being permeable to ink infused within the printing plate. A method of printing using the above plate is also disclosed.

Abstract: Hydrogen atom donor compounds are useful as contrast enhancers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazine co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements.The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

Abstract: A bleachable composition, including an acid photogenerator and a near-infrared radiation-absorbing dye or pigment, is utilized in a method of migration imaging to prevent unwanted absorptions. This composition can be incorporated either in the thermoplastic imaging surface layer of the imaging element, in the marking particles applied to the element, or both. Alternatively, the components of the bleachable composition can be separated with one in the thermoplastic imaging surface layer and the other in the marking particles. After the imaging element is marked and exposed with near-infrared radiation, the bleachable composition caused exposed portions of the imaging element to be bleached. If further bleaching is needed, the element can subsequently be exposed with near-ultraviolet radiation. A migration imaging method, which does not employ the bleachable composition of the present invention, wherein marking particles are magnetically attracted to the imaging element, is also provided.

Abstract: An optical image forming material in which the background portions thereof are not color developed (not fogged) during storage in the dark after fixing, comprising a support having thereon at least a coating layer containing (1) microcapsules containing a leuco dye which is form color when it is oxidized and a photooxidizing agent, and (2) a reducing agent and a fixing accelerator present outside of the microcapsules. The reducing agent is a hydroquinone derivative substituted by an alkyl group at each of 2- and 5-positions thereof, and the fixing accelerator is 2,2-bis(4-hydroxy-phenyl)propane.

Abstract: A direct thermal recording process wherein a direct thermal recording material is heated dot-wise and said direct thermal recording material comprises on a substrate an imaging layer containing uniformly distributed in a film-forming polymeric binder (i) one or more substantially light-insensitive organic silver salts being no double salts, said silver salt(s) being in thermal working relationship with (ii) an organic reducing agent therefor, characterized in that said reducing agent is a benzene compound the benzene nucleus of which is substituted by no more than two hydroxy groups which are present in 3,4-position on said nucleus and have in the 1-position of said nucleus a substituent linked to said nucleus by means of a carbonyl group.

Abstract: A bleachable composition, including an acid photogenerator and a near-infrared radiation-absorbing dye or pigment, is utilized in a method of migration imaging to prevent unwanted absorptions. This composition can be incorporated either in the thermoplastic imaging surface layer of the imaging element, in the marking particles applied to the element, or both. Alternatively, the components of the bleachable composition can be separated with one in the thermoplastic imaging surface layer and the other in the marking particles. After the imaging element is marked and exposed with near-infrared radiation, the bleachable composition causes exposed portions of the imaging element to be bleached. If further bleaching is needed, the element can subsequently be exposed with near-ultraviolet radiation.

Abstract: Acrylonitrile compounds are useful as co-developers when used in combination with hindered phenol developers to produce high contrast black-and-white photothermographic and thermographic elements.Acrylonitrile compounds are also useful as co-developers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazinc co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements.The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

Abstract: Hydroxylamine, alkanolamine, and ammonium phthalamate compounds are useful as contrast enhancers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazine co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements.The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

Abstract: Trityl hydrazides and formyl-phenyl hydrazines are useful as co-developers with hindered phenols in phothothermographic and thermographic elements. These co-developers have the formula:R.sup.1 --(C.dbd.O).sub.n --NHNH--R.sup.2R.sup.1 represents hydrogen and R.sup.2 represents an aryl or substituted aryl group; or,R.sup.1 represents hydrogen, alkyl and alkenyl groups of up to 20 carbon atoms; alkoxy, thioalkoxy, or amido groups of up to 20 carbon atoms; aryl, alkaryl, or aralkyl groups of up to 20 carbon atoms; aryloxy, thioaryloxy, or anilino groups of up to 20 carbon atoms; aliphatic or aromatic heterocyclic ring groups containing up to 6 ring atoms; carbocyclic ring groups comprising up to 6 ring carbon atoms; or fused ring or bridging groups comprising up to 14 ring atoms; and R.sup.2 represents a trityl group.

Abstract: Certain squaric acid derivatives are useful for the thermochemical generation of acid. The squaric acid derivatives may be used in imaging media in conjunction with acid-sensitive materials which undergo a color change when contacted by the acid generated from the squaric acid derivatives. Preferably, the acid-sensitive materials undergo an irreversible color change, so that the image can be fixed by neutralizing all the acid generated with excess base, thereby preventing further color change in the image during long term storage.

Abstract: Acid can be generated by exposing a superacid precursor to actinic radiation effective to generate superacid from the superacid precursor and heating the superacid in admixture with a secondary acid generator capable of undergoing thermal decomposition to produce a secondary acid. The superacid catalyzes decomposition of the secondary acid generator, thus increasing the quantity of strong acid present in the medium. The resultant secondary acid can be used to effect a color change in an acid-sensitive material, so providing an imaging process.

Abstract: Sulfonyl hydrazides are used as developers in phothothermographic and thermographic elements. The sulfonyl hydrazides have the formula:R.sup.1 --CO--NHNH--SO.sub.2 --R.sup.2wherein R.sup.1 and R.sup.

Abstract: A photothermographic element comprising a support bearing at least one heat-developable, photosensitive, image-forming photothermographic emulsion layer comprising:(a) a photosensitive silver halide;(b) a non-photosensitive, reducible source of silver;(c) a chromogenic leuco dye reducing agent; and(d) a binder;wherein the chromogenic leuco dye reducing agent is a chromogenic leuco redox-dye-releasing compound of the general formula: ##STR1## wherein: (i) Cp is a coupler group;(ii) N--D is a photographic developer group; and(iii) R.sup.1 is a --C(O)--NH--A--Dye group wherein Dye represents the chromophore of a thermally mobile dye; and A represents a single bond or a divalent linking group of the formula --X--R.sup.5 --L--, wherein R.sup.5 is a divalent hydrocarbon chain containing up to 12 carbon atoms, L is a single bond or a divalent group that binds the chromophore of the thermally mobile dye to R.sup.5, and X represents a single bond or an --SO.sub.2 -- group.

Abstract: A photothermographic element containing a support bearing at least one heat-developable, photosensitive, image-forming photothermographic emulsion layer is provided. The emulsion layer comprises:(a) a photosensitive silver halide;(b) a non-photosensitive, reducible source of silver;(c) a leuco dye reducing agent; and(d) a binder;wherein the leuco dye reducing agent comprises a blocked leuco dye compound of the general formula L-R.sup.1, which is capable of being oxidized to a colored form, wherein:(i) L is a group remaining after removal of a hydrogen from a leuco dye; and(ii) R.sup.1 is a C(O)--NH--SO.sub.2 --R.sup.5 group wherein R.sup.5 is an aliphatic group or an aromatic group.

Abstract: The present invention provides an imaging element comprising a support, a porous layer, a photosensitive layer containing a photopolymerizable composition and optionally a stripping layer characterized in that there is provided a barrier layer between said photosensitive layer and said porous layer said barrier layer being impermeable for the photopolymerizable composition at ambient temperature and capable of increasing its permeability with increasing temperature.

Abstract: A direct thermal printer is provided having a lamp cover member which is attached to an open end of an optical fixing device, for protecting a thermosensitive recording medium from contacting a lamp of the optical fixing device. The lamp cover member is formed with a plurality of openings for reducing the absorption of light into the lamp cover member. All edges of the openings are not parallel to the recording medium transporting direction.

Abstract: There are disclosed thermally-processable image recording materials comprising a support carrying thereon; a di- or triarylmethane thiolactone dye, an organic silver salt, a binder; and a select group of substituted purine compounds for reducing a post-processed formation of a yellowish-brown color (gilding) within such materials.

Abstract: A method for recording an image on a thermal recording material in which a plurality of color-development layers are laminated, the plurality of color-development layers being adapted to develop different colors, respectively, upon supply of thermal energy thereto and to form a substantially black color when all of the plurality of color-development layers undergo color development with a substantially identical density. With respect to a portion where a color other than black is to be developed, recording is effected such that a color-development density of each of the plurality of color-development layers becomes lower than a maximum color-development density of each of the plurality of color-development layers.

Abstract: A heat-sensitive recording material for laser recording is provided including a support having thereon a heat-sensitive layer including at least a first substantially colorless coloring component, a second substantially colorless coloring component which reacts with the first substantially colorless coloring component to develop a color, and an infrared-absorbing dye.

Abstract: Certain squaric acid derivatives are useful for the thermochemical generation of acid. The squaric acid derivatives may be used in imaging media in conjunction with acid-sensitive materials which undergo a color change when contacted by the acid generated from the squaric acid derivatives. Preferably, the acid-sensitive materials undergo an irreversible color change, so that the image can be fixed by neutralizing all the acid generated with excess base, thereby preventing further color change in the image during long term storage.

Abstract: Disclosed are an ink ribbon containing an amphiphilic acid dye or basic dye, which has an excellent thermal transfer sensitivity and which may form an image with high fixation comparable to that of silver salt photographic images, and an image forming method using the ink ribbon. The method comprises bringing the ink ribbon containing an amphiphilic acid dye or basic dye into contact with a photographic paper containing a precipitating agent capable of laking by salt formation with an acid dye or basic dye so that the acid dye or basic dye is transferred and fixed from the ink ribbon to the photographic paper by thermal stimulation.

Abstract: An image forming method is conducted by subjecting a dry silver salt image forming medium to imagewise exposure and heating to form a light-absorbing organic compound. Thereafter, the medium is subjected to polymerization exposure to imagewise polymerize the medium based on the formation pattern of the light-absorbing compound. The light-absorbing organic compound has specific sensitivities to light in order to maximize contrast.

Abstract: A migration imaging system using a laser-addressable thermoplastic imaging member 10. The imaging member 10 comprises a supporting section 15 and a thermoplastic imaging surface layer 14. A charged, uniform layer of marking particles 24 is deposited on the imaging surface layer 14. An imagewise-modulated laser beam 24 transforms selected volumes of the imaging surface layer 14 in an imagewise pattern to a permeable state. Charged marking particles 42 that overlay a transformed volume then migrate into the imaging surface layer 14, due to an electrostatic attraction to the imaging member 10, so as to be retained. Unaddressed marking particles 56 are cleaned away by particle removing device 20B comprised of a magnetic brush utilizing hard magnetic carrier particles. The imaging member 10, or solely the imaging surface layer 14, may be transferred and bonded to a receiver member such as a drum for use as an exposure mask in a xeroprinting process, or to a receiver sheet 64 to provide a hard copy reproduction.

Abstract: Certain squaric acid derivatives are useful for the thermochemical generation of acid. The squaric acid derivatives may be used in imaging media in conjunction with acid-sensitive materials which undergo a color change when contacted by the acid generated from the squaric acid derivatives. Preferably, the acid-sensitive materials undergo an irreversible color change, so that the image can be fixed by neutralizing all the acid generated with excess base, thereby preventing further color change in the image during long term storage.

Abstract: Phase-change type, reversible optical information recording medium, being possible for recording, reproducing, erasing, and rewriting of information, by use of a laser beam. This invention consists of recording thin film of ternary elements, for example, containing Ge, Te, Sb/or Bi or quaternary elements containing the fourth element of Se with which a part of Te is replaced, which is established on such surface-flat substrates as glass or plastics. In this case, the component ratio of Te and Se is selected not to be excess for other elements, such as Ge, Sb/or Bi so as to be fixed as stable compounds of stoichiometric compositions of GeTe, Sb.sub.2 Te.sub.3 /or Bi.sub.2 Te.sub.3, or GeSe, Sb.sub.2 Se.sub.3 /Bi.sub.2 Se.sub.3 when crystallized. Strictly speaking, a concentration of each component is selected to have proper ratio of the number of atomes each other so as to represent whole composition as the sum of each component.

Abstract: In an optical recording medium, a light absorbent can be incorporated into a color-developing layer without separately constituting a light absorbing layer by holding the light absorbent in a dispersed or dissolved state in a solvent soluble or heat fusible material. Thus, an optical recording medium which exhibits satisfactory image density with a small amount of the light absorbent can be provided.