Abstract: Imageable elements with improved dot stability are disclosed. The imageable elements comprise a layer of an imageable composition over a support. The imageable composition comprises an infrared absorbing compound, an acid generator, an acid activatable crosslinking agent, a polymeric binder, and about 0.01 wt % to 1 wt % of an added onium compound. The elements may be thermally imaged and developed to produce images useful as lithographic printing plates.

Abstract: The invention provides a lithographic printing for precursor having an imagable coating on an aluminum support, wherein the imagable coating comprises a polymeric substance comprising colorant groups, and wherein the aluminum support on which the coating is provided is anodized but not subsequently modified by means of a post-anodic treatment compound, and the coating does not comprise a colorant dye. The polymeric substance may also comprise pendent infra-red or developer dissolution inhibiting groups, and these groups may also be the colorant groups themselves.

Abstract: Disclosed are a printing plate material comprising a substrate and provided thereon, a component layer comprising a hydrophilic layer and an image formation layer, the hydrophilic layer being provided closer to the substrate than the image formation layer, wherein the hydrophilic layer contains an electron providing dye precursor, the image formation layer contains an organic electron accepting developing agent, and the component layer contains a light heat conversion material.

Abstract: A machine (10) hardens polymer steel backed foil stamping plates. The machine (10) includes a housing (11) providing a surface (12) upon which the plate to be hardened rests. Magnets (16) are provided to urge the steel backed polymer plate into contact with the surface (12). The polymer plate is heated to a temperature of 60 to 70° C. for 5 to 10 minutes. The polymer plates are employed in stamping and embossing of foil to another material such as paper or plastics.

Abstract: A positive working printing plate precursor is disclosed which comprises a hydrophilic support and a coating provided thereon which comprises in the order given a first layer containing an oleophilic resin soluble in an aqueous alkaline developer and a second layer comprising a water repellent-compound. Furthermore, the coating comprises an infrared absorbing dye containing a polysiloxane group providing a printing plate precursor with high sensitivity.

Abstract: A method for the preparation of a negative working lithographic printing plate is disclosed. A printing plate precursor comprising a lithographic support and an image forming layer is mounted on a printing press. A liquid containing a dissolution inhibitor is image-wise dispensed on the precursor by means of ink jet printing. The precursor is developed on press by the application of fountain and ink whereby the image areas are retained and the non-image areas are removed.

Abstract: A planographic printing member precursor comprises a first component, for example a hydroxy group containing polymer, and a second component which may be a siloxane or a compound of general formula (I), wherein M represents a silicon or a titanium atom and each of R1, R2, R3 and R4 is independently selected from hydrogen or halogen atoms; a hydroxy group; an optionally substituted alkyl, alkenyl or alkynyl group; an optionally substituted alkoxy group; or an optionally substituted saturated or unsaturated cyclic or heterocyclic group. On exposure, the second component reacts with the first component to define an oleophobic/hydrophilic material in exposed areas and in non-exposed areas the second component is removed, on processing of the precursor.

Abstract: Disclosed are a printing plate material capable of being developed on a printing press and its manufacturing method which comprises the steps of subjecting an aluminum plate to electrolytic surface roughening treatment, subjecting the electrolytic surface roughened aluminum plate to etching treatment in an aqueous alkali solution, subjecting the resulting aluminum plate to anodization treatment, whereby an aluminum support is obtained, and providing on the aluminum support an image formation layer which contains thermoplastic particles and a light-to-heat conversion dye and changes in color due to infrared laser exposure.

Abstract: A method for preparing lithographic printing plates comprising coating a substrate with a mixture including colloidal silica, fumed alumina, polyethylenimine, a quaternary ammonium polymer and a hardener; utilizing an inkjet printer with pigmented inks to print a digital image on the coated substrate; and drying the image.

Abstract: Disclosed is a printing plate material comprising a substrate and a component layer provided thereon, the substrate having a center line average surface roughness Ra of from 0.2 to 1.0 &mgr;m, and an oil-retention volume A2 of from 1 to 10, wherein the center line average surface roughness Ra is obtained from three dimension surface roughness measurement according to JIS-B-0601, and wherein an image is capable of being recorded on the component layer by imagewise exposure of infrared laser.

Abstract: The present invention provides compositions and methods of ink jetting oleophilic images onto a substrate. The composition includes an oleophilic polymer having polar moieties that is soluble in an organic carrier and adheres to a substrate. Compositions of the present invention may be used to form oleophilic image areas for lithographic printing.

Abstract: A method for the preparation of a negative working lithographic printing plate by means of ink jet printing is disclosed. This method uses a lithographic printing plate precursor comprising a lithographic support and an image forming layer containing a polymeric binder soluble in an aqueous alkaline developer. The precursor is image-wise printed by an ink jet fluid comprising a compound capable of reducing the solubility of the binder in the aqueous alkaline developer. After development a negative working printing plate is obtained.

Abstract: The recording medium comprises a recording layer. The recording layer has a first material and a second material independently dispersed. The first material has a property that a backward contact angle to a liquid lowers when the material is heated in a state of being in contact with the liquid, and that the value of the backward contact angle recovers when heated in the air. The second material has a polyorgano-siloxane structure.

Abstract: A lithographic printing plate precursor comprising a water-resistant support having provided thereon a light-sensitive layer containing fine titanium oxide grains doped with a metallic ion which absorb a visible ray and a complex composed of an organo-metallic polymer which is formed by a hydrolysis polymerization condensation reaction of a compound represented by formula (I) shown below and an organic polymer which has a group capable of forming a hydrogen bond with the organo-metallic polymer: (R0)nM(Y)x−n  (I) wherein R0 represents a hydrogen atom, a hydrocarbon group or a heterocyclic group; Y represents a reactive group; M represents a metallic atom having from 3 to 6 valences; x represents a valence of the metallic atom M; and n represents 0, 1, 2, 3, 4, 5 or 6, provided that the balance of x−n is not less than 2. A method for the preparation of a lithographic printing plate using the lithographic printing plate precursor is also disclosed.

Abstract: Metal-based printing members suitable for transfer-type imaging include a metal substrate and a hydrophilic, polymeric coating thereover. Desirably, the polymeric coating is crosslinked and withstands repeated application of fountain solution during printing. The polymeric coating can, however, undergo degradation where exposed to fountain solution so long as the ink-receptive portions—the areas where oleophilic material has been transferred onto the hydrophilic coating—remain intact.

Abstract: A negative-working heat-sensitive lithographic printing plate precursor, comprising a substrate having a water-receptive surface which has provided thereon sequentially: (1) a thermal cross-linking layer comprising an aqueous alkali-soluble resin having aromatic hydroxyl groups, a cross-linking agent capable of cross-linking the resin by heating in the presence of an acid catalyst and an acid generator; and (2) a water-soluble overcoat layer; wherein at least one layer of the overcoat layer and the thermal cross-linking layer comprise a compound capable of converting light into heat.

Abstract: Disclosed is a planographic printing plate precursor, comprising a hydrophilic support and an image forming layer containing oleophilic heat-fusible particles, wherein the hydrophilic support has voids and the void content is 20 to 40 ml/m2.

Abstract: The present invention provides a printing member having a single radiation-absorptive multiphase layer over a substrate layer that may be imaged with or without ablation.

Abstract: A lithographic printing plate precursor which comprises a support having a hydrophilic surface having provided thereon in order of a layer containing a latex (layer A) and an ink-receptive layer (layer B) whose solubility at least either in water or in an aqueous solution is converted by heat, wherein at least one layer of either layer A or layer B contains a light/heat converting agent.

Abstract: A printing plate for computer-to plate lithography having a laser-ablatable member supported by a substrate. At least one portion of the laser-ablatable member is formed form an acrylic polymer containing laser-sensitive particles. The laser-sensitive particles absorb imaging radiation and cause the portion of the laser-ablatable member containing the laser sensitive particles and any overlying layers to be ablated. Alternatively, the printing plate may include a printing member with an initial affinity for a printing fluid that changes to another affinity to printing fluid upon treatment with radiation.

Abstract: A novel lithographic printing plate precursor is disclosed, comprising a crosslinked hydrophilic layer having a crosslinked structure and containing a hydrophilic polymer compound having a hydrophilic graft chain, provided on a support.

Abstract: A printing plate useful in lithographic printing is prepared by a process comprising: (a) applying a coating composition comprising at least one polymer such as polyethylene glycol to a substrate surface to provide the surface with a water-soluble or water-dispersible polymer coating; (b) imaging the coated substrate with a toner composition comprising toner particles by imagewise applying the toner composition to the polymer coating, wherein the polymer coating has a softening temperature TS; (c) heating the imaged substrate to a temperature TF which is equal to or greater than TS; and (d) contacting the imaged substrate with a solution capable of removing the non-imaged portion of the polymer coating, wherein the process does not comprise a chemical development step and the polymer coating has a coating weight of about 0.25 to about 2.0 g/m2.

Abstract: A method for preparing a lithographic printing plate by means of ink jet printing is disclosed. The ink jet fluid contains an oleophilizing compound having in its chemical structure a boron containing group capable of reacting with the surface of a lithographic receiver.

Abstract: A conditioner composition for a printing plate with a metallic non-print areas on the printing surface contains a polymeric or oligomeric component. The polymeric component adheres to the metal (particularly, aluminum) surface of the non-print area(s) of the printing member, and has a hydrophilic portion. The conditioned printing plate is particularly useful for printing single fluid inks having an emulsified hydrophilic fluid phase.

Abstract: A heat-sensitive lithographic printing plate precursor which comprises a substrate having thereon an anodic oxidation layer, with the printing plate precursor comprising a hydrophilic layer containing at least one kind of fine particles selected from the group consisting of heat-fusible hydrophobic thermoplastic fine particles, finely divided polymers having thermally reactive functional groups and microcapsules in which compounds having heat-reactive functional groups are encapsulated, and with the anodic oxidation layer having a surface over which micropores having an average pore size of 6 to 40 nm are uniformly distributed.

Abstract: A method for the preparation of a lithographic printing plate comprises forming an oleophilic image on the surface of a hydrophilic support by depositing, preferably by ink-jetting, the desired image on the surface using an aqueous emulsion of an organic film-forming polymer which has been prepared by emulsion polymerization, whereby the polymer adheres to the surface of the printing plate forming an oleophilic film. The polymer preferably has functional groups such as sulphonate that bind the polymer to the hydrophilic surface. Preferably the polymer has a glass transition temperature of not greater than about 105° C. and where the glass transition temperature is above 50° C. the polymer, after deposition on the plate, is preferably subjected to a heat treatment to assist in film formation.

Abstract: A thermosensitive composition consisting of a mixture of polyacrylic acid, a salt of a long chain fatty acid such as silver behenate, an infra-red absorbent and modifiers such as additional polymers and fillers. Both the water solubility and affinity to water and oil changed when composition is heated.

Abstract: A process for making printing plate material suitable for imaging by laser radiation. A metal substrate is electrocoated in a bath containing a polymeric resin and laser-sensitive particles, thereby depositing a laser ablatable layer on a principal surface of the metal substrate. In one embodiment, the laser-ablatable layer is treated with a corona discharge for a time sufficient to render the layer non-ink wettable. In other preferred embodiments, the laser-ablatable layer is overcoated with an overlayer such as a non-ink wettable silicone layer or a water-wettable layer comprising an organophosphorus polymer, preferably a copolymer of acrylic acid and vinylphosphonic acid.

Abstract: Lithographic imaging using non-ablative printing members combines the benefits of simple construction, the ability to utilize traditional metal base supports, and amenability to imaging with low-power lasers that need not impart ablation-inducing energy levels. A representative printing member has a hydrophilic metal substrate and, thereover, first and second layers. The first layer has a thickness and an exposed surface and comprises a material that absorbs imaging radiation. The second layer overlies the first layer and is oleophilic and substantially transparent to imaging radiation. Exposure to imaging radiation causes the first layer and the substrate to irreversibly detach without substantial ablation, thereby facilitating removal, by subjection to the cleaning liquid, of the first and second layers where detachment has taken place.

Abstract: Positive-working imageable elements and methods for their preparation are disclosed. The elements comprise a hydrophilic substrate; a bottom layer, which contains a positive-working photosensitive composition; and a protective overlayer, which has an overlayer material that reduces the solubility of the photosensitive composition in an aqueous alkaline developer. The overlayer may be conveniently applied by a dip and rinse procedure.

Abstract: A lithographic printing plate support includes a support and a hydrophilic layer on the support, wherein the hydrophilic layer includes a polymer compound that is chemically bonded directly to the support surface and has a hydrophilic functional group.

Abstract: Provided is a lithographic printing plate comprising a support substrate having disposed thereon an ablative-absorbing layer and, optionally, a durable, ink-accepting surface layer that is not ablative-absorbing. The ablative-absorbing layer may contain a high weight percent of an organic sulfonic acid component. The printing plate may further comprise a hydrophilic polymeric layer interposed between the ablative-absorbing layer and the substrate. The printing plate also comprises a primer layer underlying the ablative-absorbing layer with an adhesion-promoting agent, such as a zirconium compound, present in the primer layer. Also provided are methods of preparing such lithographic printing plates, and methods of preparing imaged lithographic printing plates from such lithographic printing plates by imagewise exposure to a laser and a subsequent cleaning step with water or with a cleaning solution.

Abstract: A lithographic printing plate precursor comprising an image receiving layer and a waterproof substrate, wherein the image receiving layer comprises: needle filler particles or porous filler particles; and a binder resin comprising a complex of: a resin comprising at least one of a metal atom and a semimetal atom, each of the at least one of a metal atom and a semimetal atom being bonded to an oxygen atom; with a polymer compound represented by the following formula (I): 1

Abstract: A positive photosensitive printing plate is prepared wherein the photosensitivity is to near-infrared rays which do not induce a chemical change in a photosensitive component. The photosensitive material has an inclined structure from the viewpoint of dissolution of the irradiated portion in an alkali developer. The dissolution rate is such that it continuously increases from the upper, surface part of the photosensitive material to the lower part of the photosensitive material. This effect may be enhanced by diffusion of a material, preferably a polar compound, such as H2O, from the surface toward the inner lower part of the photosensitive material. Techniques for accomplishing the diffusion include contacting the surface of the photosensitive material with an atmosphere of high humidity or overlaying the photosensitive material with a layer of protective material (paper) containing moisture and heating the resultant composite.

Abstract: A heat-sensitive lithographic printing plate precursor is disclosed, comprising a metal substrate having thereon 1) an ink-receptive layer, 2) a water-receptive layer comprising a colloidal particulate oxide or hydroxide of at least one element selected from the group consisting of beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony and transition metals, or additionally 3) a water-soluble overcoat layer, at least one layer of the ink-receptive layer, the water-receptive layer and the overcoat layer containing a compound capable of converting light into heat and the ink-receptive layer containing an epoxy resin having a softening point of 120° C. or more.

Abstract: The present invention relates to a planographic printing plate precursor comprising a substrate comprising a hydrophilic surface having disposed thereon a heat-sensitive layer containing a thermoplastic particulate polymer having functional groups capable of interacting with the hydrophilic surface. Preferably, hydrophilic graft polymer chains are present on the hydrophilic surface of the substrate. The present invention further relates to a planographic printing plate precursor comprising a substrate comprising a hydrophilic surface having disposed thereon a heat-sensitive layer comprising microcapsules comprising a compound having functional groups capable of interacting with the hydrophilic surface. In addition, the present invention relates to methods of printing with the planographic printing plate precursors.

Abstract: Negative working thermally imageable elements useful as lithographic printing plate precursors and methods for their use are disclosed. The elements have a substrate, a layer of imageable composition over the substrate, and, optionally, an overcoat layer over the layer of imageable composition. The imageable composition has an allyl-functional polymeric binder. Optimum resolution and on-press performance can be attained without a post-exposure bake. The elements do not require a post-exposure bake and can be used in on-press development applications.

Abstract: An imaging member, such as a negative-working printing plate or on-press cylinder, can be prepared with a hydrophilic imaging layer comprised of a heat-sensitive hydrophilic charged polymer (ionomer) and an infrared radiation sensitive negatively-charged oxonol dye that has a &lgr;max of greater than 700 nm. The heat-sensitive polymer and IR dye can be formulated in water or water-miscible solvents to provide highly thermal sensitive imaging compositions. In the imaging member, the polymer reacts to provide increased hydrophobicity in areas exposed to energy that provides or generates heat. For example, heat can be supplied by laser irradiation in the IR region of the electromagnetic spectrum. The heat-sensitive polymer is considered “switchable” in response to heat, and provides a lithographic image without conventional alkaline processing.

Abstract: A method for making a printing plate including a step of forming a hydrophobic image area on at least a part of a hydrophilic surface of a plate. The plate surface contains a photocatalyst and the image area is formed by using an organic compound which is decomposed and removed by the irradiation of light having a higher energy than the band gap energy of the photocatalyst.

Abstract: A printing plate is prepared by the process comprising: (a) providing a substrate; and (b) applying by ink jetting to the substrate a fluid composition comprising a cationic polymer and an anionic polymer, in non-aqueous solvent. The ionic polymers interact and adhere to the substrate, so that after drying a durable printing plate is formed, without chemical development. The printing plate of this invention is capable of extended press run length and advantageously avoids the need of chemical development.

Abstract: According to the present invention there is provided a heat-sensitive material for making a negative working non-ablative lithographic printing plate including in a heat sensitive layer thermoplastic polymer beads and a compound capable of converting light into heat on a surface of a hydrophilic metal support, the layer being free of binder, and characterized in that the thermoplastic polymer beads have a diameter between 0.2 &mgr;m and 1.4 &mgr;m.

Abstract: A printing system is provided which ensures easy formation of a plate and regeneration of the plate for continued use. The press plate used in a the printing system to form an image using a water-based ink is characterized in that, (I) prior to formation of a latent image, the surface forming the latent image exhibits extra ink-repellency to the ink to be used; (2) the press plate allows a water soluble material forming the latent image to be deposited thereon; (3) the latent image can be formed by allowing the water soluble material to be deposited on the press plate surface; and (4) the press plate can be regenerated as a plate which allows a new latent image to be formed by washing the press plate with water and drying it, upon completion of ensuing processes of development and transfer.

Abstract: An imaging member, such as a negative-working printing plate or on-press cylinder, can be prepared with a hydrophilic imaging layer comprised of a heat-sensitive hydrophilic polymer having ionic moieties and an infrared radiation sensitive dye having multiple sulfo groups. The heat-sensitive polymer and IR dye can be formulated in water or water-miscible solvents to provide highly thermal sensitive imaging compositions. In the imaging member, the polymer reacts to provide increased hydrophobicity in areas exposed to energy that provides or generates heat. For example, heat can be supplied by laser irradiation in the IR region of the electromagnetic spectrum. The heat-sensitive polymer is considered “switchable” in response to heat, and provides a lithographic image without wet processing.

Abstract: A method of controlling the resolution of an image formed on a substrate comprises: (a) providing a substrate; (b) applying an image to the substrate by ink jetting onto the substrate a fluid composition comprising at least one surfactant, wherein the spreading of the fluid composition on the substrate in the presence of the surfactant is less than the spreading of the fluid composition on the substrate in the absence of the surfactant. The invention reduces the dot spreading which otherwise occurs when a substrate is imaged via ink jetting to prepare a printing plate.

Abstract: A method for preparing a lithographic printing plate by means of ink jet is disclosed. In the ink jet fluid an oleophilizing compound is incorporated containing a 1,3-dicarbonyl group in its chemical formula.

Abstract: A method for preparing a lithographic printing plate by means of ink jet printing is disclosed. The ink jet fluid contains an oleophilizing compound having in its chemical structure a phosphorous containing group capable of reacting with the surface of a lithographic receiver.

Abstract: A method for preparing a lithographic printing plate by means of ink jet is disclosed. The ink jet fluid contains an oleophilizing compound chosen from the group consisting of a catechol, a pyrogallol, and a salicylic acid.

Abstract: A method for the preparation of a lithographic printing plate comprises forming an oleophilic image on the surface of a hydrophilic support by depositing, preferably by ink-jetting, the image on the surface using an aqueous dispersion of an oligomer having in the molecule both hydrophilic and hydrophobic groups. The number of repeating units in the oligomer may be from 2 to 10 and the number of hydrophilic groups in the oligomer may also be from 2 to 10. Preferably the molecular weight of the oligomer is from about 500 to about 5000.

Abstract: A lithographic printing plate precursor comprising a hydrophilic support having thereon a heat-sensitive layer containing at least one of a thermoplastic particulate polymer having Tg of not lower than 60° C., a particulate polymer having a heat-reactive group and a microcapsule containing a compound having a heat-reactive group incorporated therein.

Abstract: A photosensitive lithographic printing plate having a photosensitive resin layer formed on an aluminum substrate subjected to electrolytic surface roughening in nitric acid or in an electrolyte composed mainly of nitric acid and further to anodic oxidation treatment, wherein the photosensitive resin layer is made of a photopolymerizable composition comprising (A) an addition-polymerizable ethylenically unsaturated bond-containing monomer, (B) a photopolymerization initiator, and (C) a polymer binder, wherein the addition-polymerizable ethylenically unsaturated bond-containing monomer (A) contains a phosphate compound having at least one (meth)acryloyl group.