Abstract: The invention provides a light-sensitive material for making lithographic printing plate through high-intensity short-time exposure which comprises a support and, provided thereon, at least a silver halide emulsion layer and a physical development nuclei layer wherein an intermediate layer comprising a water-permeable film forming polymer is provided between the emulsion layer and the nuclei layer. Furthermore, a process for making a lithographic printing plate from said light-sensitive material is provided which comprises subjecting the light-sensitive material to imagewise exposure of high intensity short time, silver complex diffusion transfer development and subsequently treatment with an oxidizing agent for silver and an oleophilic organic compound.

Abstract: The present invention provides a processing composition which is used for lithographic printing plate where silver image is used as ink receptive area for enhancing ink receptivity of the silver image. This composition contains an organic compound having two or more mercapto groups or thion groups and, in combination therewith, an aromatic sulfonic acid formalin condensate, an anionic surfactant having a polyoxyethylene group, an aromatic carboxylic acid, a hydrosulfite compound, a water-soluble polymer having a carboxyl group and having a number-average molecular weight of about 20,000 or less, a hydroxyaryl fatty acid, or an organic disulfide compound. If this composition additionally contains an oxidizing agent, it can further improve printing endurance of the printing plate.

Abstract: Printing endurance of a lithographic printing plate made by using silver complex diffusion transfer process is markedly improved and besides staining which occurs during printing can be effectively inhibited by containing in at least one of a layer which contains nuclei for physical development comprising a heavy metal of a sulfide thereof and a layer contiguous to said layer at least one water-soluble synthetic polymer having the following structural units: ##STR1## wherein A:B=100:0-50:50 (molar ratio)C:D=100:0-50:50 (molar ratio)(A+B):(C+D)=95:5-5:95 (molar ratio) and R.sub.1 represents a hydrogen atom or an alkyl group of 1-6 carbon atoms, R.sub.2 represents a hydrogen atom or an alkyl group of 1-20 carbon atoms, R.sub.3 represents an alkyl group of 1-20 carbon atoms and M represents a hydrogen atom or a cation.

Abstract: A silver halide photographic material comprising a support having thereon at least one light-sensitive layer comprising a silver halide emulsion sensitized by an infrared sensitization dye, wherein the silver halide in the silver halide emulsion contains at least 90 mol % of silver chloride and is constituted by monodisperse grains having a coefficient of variation of not more than 20%; and an image formation method using the above-described silver halide photographic photosensitive material, comprising the steps of imagewise exposing the photographic material and developing the said material in a developing solution containing at least 0.15 mol/l of sulfurous acid ions and a compound having a silver halide-adsorption accelerating group.

Abstract: The present invention provides a developer for making a lithographic printing plate by silver complex diffusion transfer process which contains a hydroxyaryl fatty acid. This hydroxyaryl fatty acid preferably has the formula: ##STR1## wherein R.sub.1 represents a straight chain alkyl group of 1-19 carbon atoms and R.sub.2 represents a straight chain alkylene group of 1-19 carbon atoms with a proviso that sum of carbon atoms of R.sub.1 and R.sub.2 is 10-20 and R.sub.3 and R.sub.4 each represents a hydrogen atom, a hydroxyl group or an alkyl or alkoxy group of 1-9 carbon atoms.

Abstract: Method for making lithographic aluminium offset printing plates according to the DTR-process by photo-exposing a photosensitive monosheet layer assemblage comprising a hydrophilic aluminium foil, a water-swellable intermediate layer comprising a non-protenic hydrophilic film-forming polymer, and a silver halide emulsion layer, applying an aqueous alkaline solution thereto in the presence of a developing agent and a silver halide solvent, allowing to reduce the photo-exposed silver halide, allowing the unreduced silver halide or complexes thereof to diffuse to said aluminium foil to form a silver image thereon, and separating said emulsion layer and said intermediate layer from the image aluminium foil. The invention also relates to the photosensitive monosheet layer assemblage used for making such printing plates.

Abstract: The invention provides a process for making a lithographic printing plate utilizing silver image as ink receptive area which is markedly improved especially in printing endurance. The process comprises subjecting a light-sensitive material for lithographic printing plate to imagewise exposure and development and then treating the resulting silver image with an oxidizing agent and a monocyclic compound comprising a nitrogen-containing single ring and having substituents on at least two atoms constituting said ring, said substituents being capable of reacting with silver ion. The oxidizing agent and the monocyclic compound may be contained separately or together in a stop solution, a fixing solution, an etch solution or damping solution or especially prepared solution.

Abstract: The present invention provides a method of preparing a planographic printing plate comprising the steps of:(1) exposing a DTR mono-sheet material containing a silver halide emulsion layer and a nuclei containing surface layer in a laser beam containing device, e.g. a helium-neon laser, an argon laser, or a semiconductor laser, wherein the said emulsion layer contains at least one emulsion showing following characteristics:(a) the emulsion consists principally of silver chloride but contains bromide ranging from 5 mole % to 40 mole % and iodide ranging from 0 to 1 mole %;(b) the emulsion belongs to the core-shell type wherein substantially all the bromide is concentrated in the core;(c) the emulsion grains contain Rhodium and/or Iridium dopants;(2) processing the DTR material by means of a developing or activator solution, containing at least an alkali agent and a silver halide complexing agent, followed by a neutralization solution.

Abstract: An aqueous lithographic conditioner solution or fix composition for use with lithographic plates made by the silver salt diffusion transfer process comprises (a) an oleophilic argentophile, (b) a quaternary ammonium surfactant and (c) a quaternary ammonium surfactant solubilized by the addition of alkyleneoxy units, the proportions and nature of the components being such as to provide the desired solution.

Abstract: Disclosed is a panchromatic silver halide photographic emulsion for use in DTR process which exhibits a high sensitivity, especially to blue light, a high contrast and a high resolving power and a photographic element containing said silver halide emulsion layer. Said emulsion contains a blue-sensitizing dye represented by the general formula [I]: ##STR1## (wherein Z.sub.1, Z.sub.2, R.sub.1, R.sub.2, X.sub.1 and m are as defined before).Said emulsion may contain, as green- and red-sensitizing dyes, those represented by the general formula [II] and [III] to attain more effectively the objects: ##STR2## (wherein Z.sub.3, Z.sub.4, Z.sub.5, Z.sub.6, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, X.sub.2, X.sub.3 and m are as defined before).Said photographic element is an excellent ligtographic printing plate.

Abstract: A process for forming printing plates using an imaging sheet which carries a layer of microcapsules containing a photohardenable composition; the imaging sheet is preferably assembled with a printing plate support, exposed and subjected to pressure to rupture the microcapsules and differentially transfer the photohardenable composition to the support; the transferred composition is hardened to provide ink-receptive images useful in printing.

Abstract: A light-sensitive material comprises a support and a light-sensitive layer which contains a reducing agent, an ethylenic unsaturated polymerizable compound and silver halide grains having a halogen composition composed of two or more halogens including iodine. The silver halide grains have a core/shell structure, and at least 50% of the silver halide grains have an aspect ratio of not more than 5. The silver iodide content in the shell is higher than that in the core. An image-forming method utilizing the light-sensitive material is also disclosed.

Abstract: Presensitized imaging element comprising a support and a light-sensitive hyrophilic layer thereon, said light-sensitive hydrophilic layer containing in homogeneously distributed state throughout the entire layer a hydrophilic (co)polymer or (co)polymer mixture, a tetraalkyl orthosilicate crosslinking agent in an amount of at least 0.2 parts by weight per part by weight of hydrophilic (co)polymer or (co)polymer mixture and a low-molecular weight diazonium salt and preferably also (a) substance(s) that increase(s) the mechanical strength and the porosity of the layer, by means of which a lithographic printing plate can be produced by imagewise exposing said imaging element to an ultraviolet radiation source, subsequently bringing it in the presence of an aqueous liquid in contact with a receptor element comprising a receiving layer containing a polyionic mordant for the diazonium salt and separating it from the receiving layer to leave the residual non-exposed diazonium salt on the receiving layer.

Abstract: A silver master plate recovery solution for a silver salt photographic plate for offset printing is disclosed which comprises (a) a hydrazine component for reducing the silver oxide layer of an image area, (b) a quaternary ammonium salt cationic activator and (c) water. The mixing ratio of the quaternary ammonium salt cationic activator is 3.0 to 20.0 wt % on the basis of the hydrazine component. The silver master plate recovery solution reduces the silver oxide layer of the image area of a silver salt photographic plate which has passed the stock time, thereby recovering the ink receptivity of the image area.

Abstract: Infra-red sensitizing dyes for silver halide having a mucleus of the general formula: ##STR1## in which: Q represents Cl or Br,R.sup.3 represents an alkyl or substituted alkyl,n is 0, 1, 2 or 3,X is an anion of molecular weight up to 400 which may be incorporated in one R.sup.3 group.

Abstract: This invention provides a silver halide photographic light sensitive material and a light sensitive lithographic printing plate material which are enhanced in sensitivity to semiconductor laser beam and improved in storage stability and printing endurance. The former comprises a support and a silver halide emulsion layer containing a sensitizing dye having a spectral sensitivity maximum in a wavelength region longer than 700 nm wherein said emulsion layer contains a water-soluble polymer containing a carboxyl group and having a number-average molecular weight of 20,000 or less and the latter comprises a support and, provided thereon, a silver halide emulsion layer containing a sensitizing dye having a spectral sensitivity maximum in a wavelength region longer than 700 nm and a physical development nuclei layer and said emulsion layer contains the above mentioned water-soluble polymer.

Abstract: Disclosed are a light sensitive material and a lithographic printing plate made therefrom by silver complex diffusion transfer process ree from peeling of layer during printing which comprises a polyester film support made hydrophilic by coating with an organic copolymer as a support and at least one undercoat layer, a silver halide emulsion layer and an image receiving layer containing physical development nuclei layer provided on said support in succession, said undercoat layer contiguous to the support containing a polyfunctional epoxy compound having at least three epoxy groups in molecule.

Abstract: There is provided a method for making a lithographic printing plate having high sensitivity, resolving power and printing endurance and free from scumming utilizing silver complex diffusion transfer process which comprises subjecting to scanning exposure of high-intensity short-time a light sensitive material comprising a support and, provided thereon, at least a silver halide emulsion layer and a physical development nuclei layer as a surface layer and then developing it with a silver complex diffusion transfer developer, the improvement which comprises subjecting the light sensitive material to imagewise exposure with scanning light of at least 700 nm, said emulsion layer containing silver halide grains mainly composed of silver chloride and a sensitizing dye having a sensitivity maximum in the long wavelength region of at least 700 nm in an amount of 3.times.10.sup.-5 -3.times.10.sup.

Abstract: A method for the production of a photographic image by silver complex diffusion transfer processing wherein a negative working silver halide emulsion material having particularly high exposure latitude and being manipulatable under room light conditions without prohibitive fogging is used, said material having a low intensity reciprocity failure (L.I.R.F). The material is contact-exposed with visible light through a sheet support carrying paper paste-up material with its information facing the silver halide emulsion layer of the photographic material, and the resulting latent image is developed in the presence of a silver halide complexing agent and the thus developed silver halide emulsion material is contacted with an image-receiving material to form according to a preferred embodiment a planographic printing plate.

Abstract: This invention provides a method for deleting images formed on offset printing plates which comprises treating the surface of undesired portion of the images formed by exposure and development with a deletion fluid which contains a ferric complex salt of an organic acid and 0.3 mol/liter or more of at least one compound selected from the group consisting of a soluble bromide and a soluble iodide. Preferred ferric complex salt is a ferric complex salt of aminopolycarboxylic acid.

Abstract: A lithographic printing plate made by silver complex diffusion transfer process from a lithographic printing plate material which contains a compound represented by the general formula [I] in photographic constituting layer is markedly improved in its printing endurance: ##STR1## wherein M represents hydrogen, an alkali metal or ammonium ion and R.sup.1 -R.sup.4 each represents hydrogen atom, alkyl group, alkenyl group, aralkyl group, aryl group, halogen atom, alkoxy group, hydroxyl group, amino group, carboxyl group, sulfone group, alkoxycarbonyl group, acylamide group or sulfonamide group and two of R.sup.1 -R.sup.4 may jointly form a ring.

Abstract: Lithographic printing plates which have such a high sensitivity as permitting use of semiconductor laser beam of low output, a high resolving power and a high printing endurance and are free from occurrence of scumming are made by a method which comprises imagewise exposing a light sensitive material which comprises a support and at least a silver halide emulsion layer and a surface physical development nuclei layer provided on the support, said emulsion layer comprising silver halide grains which contain at least silver bromide and containing at least one sensitizing dye having a maximum spectral sensitivity in the region of longer than 700 .mu.m and then developing the exposed light sensitive material with a silver complex diffusion transfer developer containing at least a thiocyanate. Further improvement can be obtained by providing an antihalation means to keep the reflectance of a light of longer than 700 .mu.m at 13-40%.

Abstract: Printing characteristics of a lithographic printing plate material using the silver complex diffusion transfer process and comprising a support and a silver halide emulsion layer and a surface physical development nuclei layer are markedly improved when the emulsion layer comprises two emulsion layers, the lower layer of which has substantially no light-sensitivity.

Abstract: Disclosed is a light sensitive material for lithographic printing plate which comprises a support and at least a silver halide emulsion layer and a surface physical development nuclei layer provided on said support wherein said silver halide emulsion layer contains at least one of the sensitizing dyes represented by the following general formulas (I), (II), (III), (IV) and (V):General formula (I) ##STR1## General formula (II) ##STR2## General formula (III) ##STR3## General formula (IV) ##STR4##

Abstract: An image deletion fluid for printing plates which use a silver image as an ink-receptive area. The deletion fluid comprises iodine and an effective excess of iodide ion, which form a triiodide complex, and a hydrophilic-matrix-forming agent. In a preferred embodiment, the deletion fluid further comprises an organic, preferably polar, solvent. The deletion fluid is applied to the surface of the plate, rubbed briefly and allowed to dry there, with no removal or rinsing away of the deletion fluid or by-products required.

Abstract: Disclosed is a lithographic printing plate material which comprises a support and at least an undercoat layer, a silver halide emulsion layer and a catalytic layer containing physical development nuclei provided in this order on said support and which utilizes silver complex diffusion transfer process, wherein content of calcium ion in at least one of lime treated gelatin-containing layers is 1000 ppm or less.

Abstract: There are disclosed photographic materials which comprise a synthetic plastic film such as a polyester film having on one surface a resin layer comprising a resin composition containing at least 50 parts by weight (based on the total weight of the resin layer) of a polyolefin which has undergone at least one kneading or a resin layer comprising a resin composition containing 50 to 95 parts by weight (based on the total weight of the resin layer) of said polyolefin and 5 to 50 parts by weight (based on the total weight of the resin layer) of a high-density polyethylene.Further disclosed is a photographic material which comprises a synthetic plastic film having on one surface a layer of the above composition and on another surface a resin layer which contains at least one of carboxy-modified polyolefin, ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer and polyolefin.

Abstract: An alkaline aqueous tanning developing solution for photographic image development comprising at least one hydroxylamine derivative. Preferred formulations may also contain at least one water-miscible polyhydroxy aliphatic organic solvent and/or a developing agent which comprises a polyhydroxybenzene compound having at least two hydroxy groups and at least one electron withdrawing and good leaving group suitable for nucleophilic addition.

Abstract: Disclosed is a light-sensitive photographic element for negative type lithographic printing plates high in sensitivity and contrast which comprises a support having thereon a light-sensitive silver halide, a metal salt particle having substantially no light-sensitivity, a compound which reacts with an oxidized developing agent produced by development to release a compond which acts as a solvent or a solution physical development accelerator for said metal salt particle and physical development nuclei.

Abstract: Photographic silver complex diffusion transfer reversal process wherein the photographic material is spectrally sensitized with a dye corresponding to the general formula of the description, wherein said dye provides to the silver halide emulsion layer a spectral sensitivity mainly in the range of 400 to 500 nm and does not extends its spectral sensitivity substantially beyond 500 nm, and wherein the handling (exposure, development and diffusion transfer) of the photographic material during said steps is effected in yellow safelight corresponding to the light transmitted by a specified cut-off filter without causing fog.

Abstract: Disclosed is a method for plate-making which comprises imagewise exposing by scanning type flash exposure a lithographic printing plate comprising a support and at least a silver halide emulsion layer containing at least 70 mol % of silver chloride and prepared with addition of a water soluble iridium compound during emulsification or physical ripening of silver halide and a water soluble gold compound at any time before coating of the emulsion and thereafter subjecting the exposed emulsion to diffusion transfer development.

Abstract: A light-sensitive material for a silver salt diffusion transfer process is described, having an antihalation layer containing at least one oil-soluble dye represented by following general formula (I) ##STR1## wherein X represents a benzene ring, a thiazole ring or a benzothiazole ring each having at least one electron attractive group selected from a nitro group, a cyano group, an alkylsulfonyl group, a halogen atom, and a trifluoromethyl group; R.sub.1, R.sub.2, R.sub.3, R.sub.4 each represents hydrogen, a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 12 carbon atoms, a substituted or unsubstituted alkylamido group having 2 to 30 carbon atoms or a substituted or unsubstituted arylamido group having 6 to 30 carbon atoms; any Y and Z each represents hydrogen or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms.

Abstract: Disclosed is a method for the direct making of printing plates for multicolor lithography capable of faithfully reproducing repeatedly continuous gradation multicolor original, which comprises using color separation filters for at least blue, green, and, red and repeating a sequence of the steps of shielding an exposure section against light by a light shielding means; feeding to said exposure section a magazine containing a sensitive material convertible into lithographic printing plate, which material bears a panchromatically sensitized photographic layer; bringing said sensitive material into close contact with a contact screen; exposing said sensitive material through a lens and a color separation filter to the reflected light from a continuous gradation multicolor original; and sending the exposed sensitive material to a processing bath section.

Abstract: Lithographic printing plates which have on a support at least one hardened gelatin-containing layer which contains a photographic gelatin and a low molecular-weight gelatin are improved in printing endurance, e.g., resistances against ink-staining and blinding of image areas.

Abstract: Composition and process for enhancing silver images. A composition comprising an oxidizing agent for metallic silver and a silver ion insolubilizing agent is reacted with photographically produced silver deposits. The composition and process is particularly useful in enhancing the lithographic utility of photographically produced silver deposits which function as the inkable image area of lithographic printing plates.

Abstract: A lithographic printing plate having metallic silver image areas is treated with a proteolytic enzyme and an oleophilizing compound to improve ink receptivity.

Abstract: A method for the preparation of a planographic printing plate wherein a sheet material, which comprises an exterior hydrophilic colloid layer having concentrated on its surface a silver image formed by the silver complex diffusion transfer process with NiS or mixed crystal NiS.Ag.sub.2 S development nuclei in which the molar ratio of NiS to Ag.sub.2 S is not smaller than 1:1, is treated with a liquid for hydrophobizing the silver image for planographic printing, such liquid containing in dissolved state a heterocyclic compound corresponding to one of the following tautomeric structures (A) and (B) or (C) and (D): ##STR1## wherein: R.sup.1 represents hydrogen, amino or acylamino,R.sup.2 represents an alkyl group, andR.sup.3 represents an alkyl group, or an alkanamido-arylene group.

Abstract: A silver halide sensor type polymerizable light-sensitive material is disclosed. The material is comprised of a support having a silver halide photographic emulsion layer and a polymerizing layer adjacent to the emulsion layer. The polymerizing layer contains a nongaseous ethylenically unsaturated compound capable of undergoing addition polymerization upon reduction of the silver halide with a reducing compound. The material is capable of producing printing plates having good inking property and good printing durability. The material maintains the sensitivity and high resolving power of a silver halide photographic light-sensitive material.

Abstract: Disclosed is a photosensitive element for the production of lithographic printing plates improved in printing endurance comprising a support, a physical development nuclei layer, and at least one gelatin-containing layer including a silver halide emulsion layer disposed under said nuclei layer, which is adapted to the silver complex diffusion transfer process to utilize the transferred silver image on said nuclei layer as ink-receptive areas, all of the gelatin-containing layers having a pH value below the isoelectric point of the gelatin used in each layer. Further improvement can be attained by using a photographic gelatin and a low molecular weight gelatin in at least one of said gelatin-containing layers.

Abstract: Disclosed is a process for making a lithographic printing plate by utilizing the silver complex diffusion transfer process and using a neon-helium laser or an LED which comprises imagewise exposing to the radiation a photosensitive element including an emulsion layer which is spectrally sensitized with an anion- or betaine-type meso-substituted trimethine cyanine dye having at least one .beta.-naphthothiazole nucleus and developing the element by the silver complex diffusion transfer process.

Abstract: A lithographic printing plate with a markedly improved printing endurance is obtained by the silver complex diffusion transfer process when the diffusion transfer development treatment is carried out in the presence of at least one thione compound having a non-enolizable thione group, an adjacent nitrogen atom with an attached substituent R and represented by >N-R, and a group of atoms selected from carbon, nitrogen, oxygen and sulfur atoms which may carry the substituent R, said group of atoms being necessary for forming a 5- or 6-membered ring having no aromatic condensed ring, said substituent R having 1 to 3 carbon atoms or no carbon atom.

Abstract: This invention comprises a process for molding a three dimensional decorative article where cored out or raised portions extend to a depth of at least 0.6 centimeter, said process comprising generating electronically a line drawing of said article and electronically displaying the drawing; photographing said drawing to form a photographic transparency; positioning said transparency over a layer of a liquid photopolymer having a depth greater than 0.6 centimeter; exposing said photopolymer through said transparency to actinic light to set the photopolymer; and removing the liquid from the set photopolymer to form a three dimensional article having the appearance of said drawing.

Abstract: Disclosed are a deletion fluid for offset printing plates which contains an S-triazine compound represented by the following general formula: ##STR1## (wherein R.sub.1 and R.sub.2 represent --SH or --OH and when either one of R.sub.1 or R.sub.2 is --SH, the other may be NHR wherein R is H or --R'---COOH wherein R' is an alkylene group or arylene group) and a method for deletion of undesired portion of images formed on an offset printing plate with said deletion fluid.

Abstract: Process for the production of a planographic printing plate by means of the silver complex diffusion transfer reversal process comprising the steps of:image-wise photo-exposing a silver halide emulsion layer; developing the resultant latent image in the presence of a silver halide complexing agent and contacting the exposed silver halide emulsion layer with an anodized aluminium platecharacterized in that the thickness of the anodized surface layer is in the range of 0.50 to 2.00 .mu.m, the anodized plate before contact of the same with the emulsion has been hydration-sealed in the temperature range of 60.degree.-80.degree. C., and the development of the light-sensitive material is carried out with a developing composition having a pH of at least 12, and containing:dissolved sulphite,dissolved thiosulphate, anda mixture of hydroquinone and at least one secondary developing agent of the class of 1-phenyl-3-pyrazolidinones and p-N-methylaminophenol.

Abstract: Printing characteristics such as ink receptivity and printing endurance of a lithographic printing plate which utilizes as ink receptive areas the photographically formed silver or silver halide image can be improved by treating said printing plate in the presence of a polymer compound containing in its principal and/or side chain an aromatic nucleus bearing a hydrophilic substituent group, said printing plate containing in at least one of its constitutive layers as hydrophilic high molecular weight-binder.

Abstract: A processing solution composition for treating an image receiving layer in silver complex diffusion transfer process, which contains 1.7.times.10.sup.-3 to 1.7.times.10.sup.-2 mole/liter of a bromide and 2.0 to 12.0 mole-% of potassium ion based on total cations of the salts contained in the composition accelerates the transfer speed and gives a silver image high in maximum density, contrast and sharpness to the image.

Abstract: A photolithographic sheet capable of forming a lithographic printing plate upon imaging via silver salt diffusion transfer comprising a support, a silver halide emulsion, and a receptor layer overlying the emulsion, the receptor layer comprising a high molecular weight hydrophilic polymer and catalytic nuclei for silver salt diffusion transfer development, the major proportion of the polymer being a dialdehyde polysaccharide.

Abstract: Surface treatment of lithographic printing plate which utilizes as ink receptive areas a photographically formed image silver per se or image silver halide per se is carried out in the presence of an organic compound having at least one mercapto or thione group and at least one hydrophilic group in the same molecule and an inorganic water-insoluble fine powder having a particle size of 0.1.mu. or less after imagewise exposure of a silver halide emulsion layer and processing thereof to develop an image, whereby ink receptivity, anti-staining property and printing endurance of the plate can be improved.

Abstract: Process for the production of a reverse reading positive line and/or halftone image suited for use in the production of a lithographic offset printing plate, said process comprising the steps of:(1) photo-exposing a photographic negative working silver halide emulsion material comprising a negative working silver halide emulsion layer on a transparent film support and an anti-halation layer either between the emulsion layer and the film support or at the side of said support opposite the emulsion layer, the exposure of the emulsion layer occurring through the support and the anti-halation layer in a camera without a reversing optical system,(2) bringing the emulsion layer side of the photographic material into contact with an image-receiving material to form by diffusion transfer processing a visible silver image upon the latter, and(3) separating the photographic material from the image-receiving material.

Abstract: Method for making lithographic printing plates by silver salt diffusion transfer process is disclosed. That is, lithographic printing plates having excellent printing endurance are obtained by carrying out the diffusion transfer processing in the presence of a compound having the ring structure ##STR1## which may be present in at least one constitutive layer of the printing plate materials (photographic materials) used for making the printing plates or in the diffusion transfer processing solution.