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: Disclosed is an image receiving material for silver complex diffusion transfer process which contains gelatin having a calcium content of about 1,000 ppm or less. This image receiving material provides improved silver image density. Further improvement can be attained when said gelatin has a jelly strength of 280 g or above.

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: 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: Transfer images of high contrast, high density and high sharpness can be obtained by DTR process wherein all of the physical development nucleus particles are covered with a water permeable colloid having a thickness of at least 10 times the average diameter of the nucleus particles and all of the physical development nucleus particles are substantially two-dimensionally distributed at such intervals as capable of forming a continuous transfer developed silver.

Abstract: In a silver halide photographic material, at least one mercapto complexing agent for silver salt is contained in at least one photographic constituting layer and at least one anion or betaine type cyanine sensitizing dye is contained in silver halide emulsion layer to improve photographic defects such as reduction of sensitivity, softening in tone, etc.

Abstract: Lithographic printing plates having high ink receptivity, suffuring no ink stains and having much improved printing endurance can be produced by silver complex diffusion transfer process from lithographic printing plate materials comprising a support having thereon at least both silver halide emulsion layer and physical development nuclei layer wherein the diffusion transfer processing is carried out in the presence of 2-mercaptobenzoic acid derivatives or, besides this 2-mercaptobenzoic acid derivatives, at least one compound selected from the group consisting of alkanolamines and cyclic imide compounds which may be contained in at least one layers of the lithographic printing plate materials and/or the diffusion transfer developing solutions.

Abstract: In production of lithographic printing plates by developing a photographic material comprising a support having thereon at least both silver halide emulsion layer and physical development nuclei layer by silver complex diffusion transfer process to form transfer silver to be used as ink-receptive portions of the lithographic printing plates, when the development is carried out in the presence of a cyclic imide compound (alone or in combination with sulfites, thiosulfates, thiocyanates or alkanolamines) as defined hereinafter, ink-receptivity of the transfer silver image portions and printing endurance of thus obtained printing plates are improved. Moreover, the non-image portions have no or substantially no stains.

Abstract: A liquid composition for treating surface of lithographic printing plates, especially etching liquid and dampening liquid which essentially consists of (a) phosphoric acids, (b) nitric acid or salts thereof and (c) nitrous acid or salts thereof and which has all characteristics required for treating liquids used for offset printing, has excellent ability of rendering the non-image areas oil-unreceptive and has rust resistance for all metals. This composition may additionally contain aminopolycarboxylates, polyol compounds and inorganic fine particles.

Abstract: The present invention provides a lithographic printing plate, which is made by exposing a photographic material having a silver halide photosensitive emulsion layer, developing the exposed material and treating the developed material with a conversion liquid comprising a solvent for a silver halide and an organic compound capable of forming a compound which is more stable and has a lower solubility than a soluble silver complex formed by said solvent.

Abstract: A lithographic printing plate which utilizes a photographic process and which is excellent in ink-repellency of non-image areas, have no stains with oily materials or fingerprints of workers, shows no reduction of ink-repellency of non-image areas and ink-receptivity of image areas with the lapse of time and can provide prints with no stains and clear images is produced by a neutralizing solution used in photographic treatment containing colloidal fine particles, preferably in combination with a hygroscopic polyol compound.

Abstract: An improved direct offset printing plate high in photographic speed which utilizes silver complex diffusion transfer is obtained by using as a silver halide emulsion a direct positive silver halide emulsion which comprises silver halide grains which contain at least 80 mol % of bromide, the surface of said silver halide grains having thereon an electron acceptor and at least one sensitizing dyes selected from the group consisting of those having the following general formula (I): ##STR1## and those having the following general formula (II): ##STR2## (wherein Z, R.sub.1 -R.sub.3, M, A and p and q are as defined in the specification).

Abstract: Printing characteristics of a lithographic printing plate material using the silver complex diffusion transfer process are markedly improved by including in layer which contains nuclei for physical development or a layer adjacent thereto at least one member selected from the group consisting of polyfunctional synthetic polymers containing a functional group having an affinity to said nuclei and a functional group providing hydrophilic property and developing agents for silver halide.

Abstract: A direct offset printing plate which comprises a support and a photographic silver halide emulsion layer and a layer containing nuclei for physical development which are coated in this order on said support. Said emulsion layer comprises fogged direct-positive silver halide emulsion wherein silver halide grains contain at least 80 mol % of bromide and has an electron acceptor on their surface and the weight ratio of binder and silver is 1/5-2. The coating amount of silver is 0.5-2.5 g/m.sup.2.

Abstract: Printabilities of offset printing plates which utilizes silver complex diffusion transfer process are improved by adding to silver halide emulsion at least one of betaine type cyanine dyes and anion type cyanine dyes.