Abstract: A process for making thermally imageable negative working compositions comprising the steps of:

Abstract: According to the present invention there is provided a heat-sensitive material for making lithographic plates comprising in the order given on a support an IR-sensitive oleophilic layer and an ablatable cross-linked hydrophilic layer comprising an inorganic pigment and a hardener, characterized in that the ratio of said inorganic pigment over the hardener is comprised between 95/5 and 75/25 by weight.

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: 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: A process for preparing an ink-jet system printing plate, wherein in a planographic printing plate precursor having an image receiving layer containing zinc oxide and a binder resin on a water-resistant support, the surface of the image receiving layer has a water-contact angle of 50° or more, and image formation is carried out according to a hot melt type ink-jet system by heat melting an ink composition that is solid at ordinary temperature and spraying the droplets of the ink composition in a heat melt state from a nozzle onto the image receiving layer, and a nonimage area of the image receiving layer is then subjected to a desensitizing treatment by a chemical reaction to prepare a planographic printing plate.

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 process for preparing an ink-jet system printing plate, wherein an image is formed according to a hot melt type ink-jet system by heat-melting an ink composition that is solid at ordinary temperature, spraying droplets of the ink composition in a hot melt state from nozzles onto an intermediate transferrer to form an image, and contact-transferring the image on the intermediate transferrer to an image receiving layer of a planographic printing plate precursor, the image receiving layer being provided on a water-resistive support and containing zinc oxide and a binder resin, and thereafter, a nonimage area of the image receiving layer is desensitized by chemical reaction treatment to prepare a planographic 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: An on-press recording type lithographic printing method involving an ink jet process which comprises ejecting an oil-based ink onto a printing plate material mounted on the plate cylinder of a press utilizing an electrostatic field according to signals of image data, whereby an image is directly formed on the surface of said printing plate precursor, thereby preparing a printing plate which is then used as it is to effect lithographic printing, characterized in that when any abnormality occurs, the formation of image is suspended and/or the cause of abnormality is removed.

Abstract: An improved ink cartridge of the type used to dispense ink in automatic lithographic presses. The ink cartridge comprises a hollow cylindrical body for holding a supply of extrudable ink, a plunger and a dispensing fitment. The improvement comprises a valve member mounted over a central aperture in the dispensing fitment and a flexible molded plastic spring that biases the valve member in the closed position. The valve member opens when subjected to pressure from the ink and closes automatically and completely when the ink pressure is less than the biasing force of the flexible spring.

Abstract: A printing plate is prepared by the method comprising: (a) providing a substrate; and (b) applying by ink jetting to the substrate a fluid composition comprising an acidic polymeric compound, in which the acid groups of the acidic polymeric compound are at least partially neutralized with base, providing a printing plate that is ready-to-use on a press without having to develop it. The printing plate of this invention is capable of extended press run length and advantageously avoids the need of chemical development.

Abstract: A method of computer-to-cylinder lithographic printing, comprising: loading a plate material on a rotative plate cylinder of a lithographic printing apparatus; rotating the plate cylinder having loaded thereon the plate material; forming an image directly onto the plate material by an inkjet image-recording process which comprises ejecting an oil-based ink from a recording head having a plurality of ejecting channels, based on image data signals, utilizing an electrostatic field, to prepare a printing plate; subsequently performing lithographic printing with the thus prepared printing plate, wherein the recording head is driven so that every n'th channel thereof is actuated in a common phase, and wherein the plate cylinder is rotated to give a surface rotational speed V (mm/sec) of the plate material as represented by the following formula: V=25.4×(f×n)/N wherein N represents a recording resolution (dots/25.

Abstract: Provided is a planographic printing plate precursor having the advantages of good developability in printers, high sensitivity and a long press life. On a support having a hydrophilic surface with hydrophilic graft polymer chains existing therein, formed is a thermosensitive layer containing a polymer having, in the molecule, a functional group capable of interacting with the hydrophilic graft polymer and a functional group that undergoes hydrophilicity/hydrophobicity conversion through exposure to heat, acid or radiation to fabricate the planographic printing plate precursor.

Abstract: A method for preparing a lithographic printing plate by means of ink jet is disclosed. The ink jet fluid contains an oleophilizing compound as defined in the description. Preferred compounds are 8-hydroxyquinolines, 7-hydroxybenzimidazoles, and 7-hydroxybenztriazoles.

Abstract: A fluid composition suitable for ink jetting upon a substrate, which includes a copolymer having a low surface energy and a plurality of tertiary amine sites, where the tertiary amine sites are at least partially neutralized with an acid; a nonionic or cationic surfactant; and water. The fluid composition may be used to prepare a printable media comprised of a substrate and an ink receptive thermoplastic image layer supported on the substrate; where the ink receptive layer contains a copolymer having a low surface energy and a plurality of tertiary amine sites, the amine sites being at least partially neutralized with an acid.

Abstract: A printing plate is prepared by the method comprising: (a) providing a substrate; and (b) applying by ink jetting to the substrate a fluid composition comprising a compound which comprises at least one nitrogen-containing heterocyclic moiety, providing a printing plate that is ready-to-use on a press without having to develop it. The printing plate of this invention is capable of extended press run length and advantageously avoids the need of chemical development.

Abstract: A process for making lithographic sheet 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.

Abstract: An imaging device for forming an image on a printing form, includes an imaging head containing a multiplicity of mutually parallel conductive pins separated from one another by an insulating material, a voltage source for a high-frequency alternating voltage, and a multiplicity of electronic switches, respectively, connected at one end thereof to one of the conductive pins, and at the other end thereof to the voltage source. Also disclosed are a method of operating the imaging device, and a printing form whereon the imaging method is performed.

Abstract: According to the present invention there is provided a method for making a negative working non-ablative imaging material, suitable for making a lithographic printing plate, including the steps of applying a dry powder containing at least a compound capable of converting light into heat and an organic compound on a surface of a non-electrically charged metal support, characterized in that the amount of organic compound in the powder ranges from 51 to 95% by weight.

Abstract: According to the present invention there is provided a method for making a lithographic printing plate including the steps of dispensing in a predetermined pattern a latex of particles of a hydrophobic polymer onto an optionally modified hydrophilic surface of a lithographic base, characterized in that the hydrophobic polymer and the optionally modified hydrophilic surface of the lithographic base have mutually reactive groups.

Abstract: When a solid ink printing master plate is constructed by liquefying by heating an ink composition which exists as a solid at room temperature, imparting some jet energy thereto thereby jetting out ink droplets, and then fixing the thus spattering ink droplets onto a substrate, the adhesion strength between the ink composition and the substrate is controlled to 25 g/mm2 or more.

Abstract: A process is provided for a printing form for wet offset printing. A printing style is formed on an ink-transferring surface of the printing form (12) by forming ink-absorbing and ink-repelling areas. For illustration, the ink-transferring surface is wetted with a moistening agent. The areas of the moistened surface that are to be made into ink-absorbing areas are dried in a specific manner, and a material that absorbs printing ink is uniformly applied to the ink-transferring surface with the still dry areas. It is also possible to uniformly apply to the ink-transferring surface first a flowable material that absorbs printing ink, to dry the areas to be made into ink-absorbing areas in a specific manner, and to remove it from the areas to be made into ink-repelling areas by means of moistening agent.

Abstract: A printing machine includes a printing form, an optical imaging unit for directly imaging the printing form, and an inking unit for inking the printing form, the printing form having a surface formed of a material with wetting properties reversibly changeable between a state with a very small contact angle and a state with a relatively large contact angle, the state with a small contact angle being achievable by action of light having a wavelength shorter than a material-specific wavelength, and a cleaning device for cleaning the surface of the printing form; and a printing process performed with the printing machine.

Abstract: A process for imaging a lithographic printing plate having a coating containing diazo resins. An ink jet printer is used to apply micro drops of a basic chemical solution that insolubilizes the affected areas of the coating to a developing solution. The latent image may be cured by heating the plate for a short period, and is then developed. The process works with conventional, commercially available lithographic plates and developers.

Abstract: A method for preparing a printing form and a method of printing are disclosed. A coating of a radiation sensitive ink on a lithographic support having a hydrophilic surface is imaged. The unexposed areas of the coating are removed to produce a printing form, which is used for printing. Preferably, the same radiation sensitive ink is used for printing as is used in the coating, and, preferably, the desired printing run length is predetermined and the thickness of the coating determined according to the desired run length.

Abstract: The effects of interfacial transition between organic and inorganic layers of a lithographic printing member are ameliorated by incorporating an inorganic component within the matrix of the organic layer. In a first aspect, a lithographic printing plate having adjacent organic and inorganic layers is fabricated by depositing a curable polymer, softening the polymer, and integrating an inorganic material therewith. The polymer is then cured to immobilize the integrated deposition material, and the desired inorganic layer is applied over the deposited inorganic material (and any exposed portions of the polymer). In a second aspect, a graded structure is built up on a substrate in successive deposition steps. Both polymer precursors and an inorganic filler material are deposited in stages, with each stage containing a desired ratio of polymer to filler.

Abstract: A solid-ink printing original plate which comprises a substrate and an image comprising ink dots formed on the substrate, and which is produced by a process comprising the steps of: melting a solid ink that is a solid at a room temperature; and jetting the melt of the solid ink onto a substrate to form ink dots, wherein the solid ink has a penetration index of not more than 5 at a room temperature. Also disclosed is a process for producing the solid-ink printing original plate.

Abstract: A substrate is coated with a first material which is soluble in a first solvent, whereupon a second material which is strongly adherent to the first material and insoluble in the first solvent is selectively applied by an ink jet printer. The substrate is then developed in the first solvent to establish the image. In a preferred embodiment the substrate is hydrophilic, the first material is a negative working photosensitive material, and the second material is a transparent adhesive, which permits curing the first material by exposure to actinic light after the development step. The adhesive is then removed. In an embodiment directed to a waterless plate the substrate includes a surface coating of silicone, and the first material is a primer which promotes adhesion of a second material in the form of an oleophilic adhesive which is selectively applied. The primer is then developed to expose the silicone on the non-image areas.

Abstract: A direct drawing type lithographic printing plate precursor comprising a water-resistant support having provided thereon an image-receiving layer, the image-receiving layer being formed from a dispersion comprising: an inorganic pigment comprising silica particles having an average particle diameter of from 1 to 6 &mgr;m and ultra-fine particles of inorganic pigment having an average particle diameter of from 5 to 50 nm, at a weight ratio thereof of from 40:60 to 70:30; and a hydrophilic binder resin comprising at least one modified hydrophilic binder resin which is modified with a silyl functional group represented by the following formula (I): —Si(R)n(OX)3-n  (I) wherein R represents a hydrogen atom or a hydrocarbon group having from 1 to 12 carbon atoms; X represents an aliphatic group having from 1 to 12 carbon atoms; and n represents 0, 1 or 2. Also disclosed are methods of preparing a lithographic printing plate using the direct drawing type lithographic printing plate precursor.

Abstract: A printing plate precursor for direct receipt of an image-wise applied ink receptive layer the precursor having a desorbable surfactant adsorbed on at least one surface in an amount effective to improve the resolution of the subsequently image-wise applied ink receptive layer. The printing plate precursor can be used to prepare a printing plate having improved resolution. The printing plate may be prepared by (a) applying a desorbable surfactant to at least one surface of a printing plate substrate, (b) removing non-adsorbed surfactant from the surface, (c) applying a fluid composition containing an ink receptive material onto at least a portion of the surface in the form of a desired image, thereby providing an ink receptive image layer; and (d) removing the desorbable surfactant from any area of the surface which does not form part of the desired image.

Abstract: A photosensitive lithographic printing plate has an aluminum support anodized and treated with an aqueous solution of polyvinylphosphonic acid adjusted to pH 1.5 or below to ensure no deterioration of impression capacity and prevention of the water-ink balance scum in the lithographic printing plate made therefrom even when a cleaner is used in the course of printing.

Abstract: A solid-ink printing original plate which comprises a substrate and an image comprising an ink dot formed on the substrate, and which is prepared by a process comprising the steps of: melting a solid ink that is a solid at a room temperature; and jetting the melt of the solid ink onto a substrate to form an ink dot, wherein the ink dots that have solidified on the substrate have an ink dot height of at least 5 &mgr;m, and a ratio (aspect ratio) of the ink dot height to the minor axis size of the ink dot of from 0.05 to 0.5. Also disclosed is a process for producing the solid-ink printing original plate.

Abstract: A method of lithographic printing comprising forming an image based on signals of image data directly on a printing plate precursor mounted on a plate cylinder of a printing press, thereby preparing a printing plate, and conducting lithographic printing, wherein the formation of image on the printing plate precursor is carried out by an ink jet recording method in which oil-based ink is ejected utilizing an electrostatic field. According to the method of the present invention, a large number of prints having clear images can be obtained. Further, a printing plate is directly formed corresponding to digital image data in a printing press, and lithographic printing is performed at a low cost and a high speed.

Abstract: A method of preparing a printing plate comprises producing an oleophilic image on the surface of a support by ink-jet printing the image on the surface using an aqueous solution or aqueous colloidal dispersion of a polymer bearing water-solubilizing groups wherein the water-solubilizing groups interact with the surface of the support thereby binding the polymer to the support and rendering the polymer insoluble.

Abstract: A printing unit with a rotatable print cylinder and a rotatable blanket cylinder is provided. A tubular printing blanket is removably mounted on the blanket cylinder. The printing unit may have an imaging unit mounted therein. A printing member, which is mountable on the print cylinder, is imaged by the imaging unit inside the printing unit. The printing member has a continuous surface and may be removed axially from the print cylinder. The printing unit may be configured as a cantilever printing unit, or, alternatively, may be configured with both a gear side frame and a work side frame for supporting the print and blanket cylinders. In order to provide a variable-cutoff capability, a plurality of print cylinder saddles may be provided. Each print cylinder saddle has the same inner diameter for mounting on the print cylinders. However, in order to provide a variable cut-off, the print cylinder saddles may have a variety of outer diameters.

Abstract: The present invention provides a record sheet used in an electro-coagulation printing method for forming characters and images on a cylinder as an electrode with an ink which coagulates with electric charge and for transferring the characters and images to the record sheet, wherein the wet time is 15 milliseconds or less, obtained from the absorption curve of pure water measured by a dynamic scanning absorptometer. Preferably, the record sheet has 5 ml/m.sup.2 s.sup.-1/2 or more absorption coefficient, and more preferably, has contact ratio measured by a specular reflection smoothness tester under a pressure of 40 kg/cm.sup.2 with a ray having a wavelength of 0.5 .mu.m is 40% or more. The record sheet can be used for various print sheets, in particular, for business form sheets and newspaper sheets.

Abstract: A plate material the surface of which is formed of film including as its major component a material whose surface changes from a lipophilic state to a hydrophilic state by a photocatalytic reaction and returns to a lipophilic state when subsequently subjected to a heat treatment is used for making a printing plate. The plate material is exposed to active light over the substantially entire surface thereof with image-wise part kept unexposed. The part exposed to the active light becomes hydrophilic and repels ink while the part unexposed to the active light is kept lipophilic and receives ink. When the plate material is subsequently heated, the hydrophilic part is rendered lipophilic and the plate material can be reused.

Abstract: According to the present invention there is provided a method for making a lithographic printing plate comprising the image-wise exposure of a heat-sensitive imaging element with a laser and developing said imaging element by rinsing it with plain water or an aqueous solution. To improve ink-uptake the imaging element is exposed on an external drum recorder whereby the pixel dwell time of the laser is above 0.1 .mu.

Abstract: An imaging member can be prepared by imagewise application of a fluid onto a water-soluble fluid-receiving layer coated on a hydrophilic support. Application is preferably accomplished by ink jet printing. The fluid is dried or cured to form an oleophilic image on the fluid-receiving layer. After removal of the non-imaged areas, the resulting imaging member can be used for lithographic printing. The fluid-receiving layer is designed to protect the resulting imaging member from fingerprints or other handling defects.

Abstract: Provided is a media-fluid material set which comprises a media with a support that bears a hydrophilic receiving surface together with a fluid material comprising a liquid carrier medium and a reactive transition metal complex of a fluorinated organic acid. After application of the fluid material to the hydrophilic receiving surface, the reactive complex reacts to form an ink-releasing layer. Such a media-fluid material set can be advantageously used in preparing waterless lithographic printing plates with ink-releasing layers comprising such fluorinated reaction products. Also provided are imaged waterless lithographic printing plates with such ink-releasing layers made by an ink jet printing application or by laser-induced thermal ablation, and methods of making such waterless lithographic printing plates.

Abstract: An imaging member can be prepared by imagewise application of a fluid onto a water-soluble fluid-receiving layer coated on a hydrophilic support. Application is preferably accomplished by ink jet printing. The fluid is dried or cured to form an oleophilic image on the fluid-receiving layer. The fluid-receiving layer must form a contact angle of at least 20.degree. with the applied fluid. After removal of the non-imaged areas, the resulting imaging member can be used for lithographic printing.

Abstract: The present invention provides a process for the preparation of a hot-melt ink jet process printing plate capable of printing many sheets of printed matters having a sharp image quality free of background stain. The present invention concerns a novel process for the preparation of an ink jet process lithographic printing plate which comprises preparing a direct imaging lithographic printing plate precursor comprising a water-resistant support having an image-receiving layer containing an inorganic pigment and a hydrophilic binder resin as main components provided thereon, and then jetting through a nozzle ink droplets obtained by heating and melting a solid ink composition at ordinary temperatures onto the image-receiving layer to form an image thereon by a hot-melt ink jet process, characterized in that the image-receiving layer comprises as the inorganic pigments a particulate silica having an average grain diameter of from 1 to 6 .mu.

Abstract: A substrate is coated with a first material which is soluble in a first solvent, whereupon a second material which is strongly adherent to the first material and insoluble in the first solvent is selectively applied by an ink jet printer. The substrate is then developed in the first solvent to establish the image. In a preferred embodiment the substrate is hydrophilic, the first material is a negative working photosensitive material, and the second material is a transparent adhesive, which permits curing the first material by exposure to actinic light after the development step. The adhesive is then removed. In an embodiment directed to a waterless plate the substrate includes a surface coating of silicone, and the first material is a primer which promotes adhesion of a second material in the form of an oleophilic adhesive which is selectively applied. The primer is then developed to expose the silicone on the non-image areas.

Abstract: There is described a method of preparing water-less lithographic plate which comprises imagewise exposing a lithographic plate coated with a photosensitive composition, processing the exposed plate in an aqueous based developing liquid to remove those areas of the photosensitive composition which are removable by the developing liquid, drying the plate and coating the plate with an ink releasing coating composition which adheres to those areas of the plate from which the photosensitive composition has been removed, but which does not adhere to those areas of the plate from which the photosensitive composition which has not been removed, further treating the plate to cure or fix the ink-releasing composition thus providing ink-receptive areas of the plate which are those areas of the plate from which the photosensitive composition which has not been removed in the developing liquid and ink-releasing areas of the plate which are covered with the cured ink-releasing composition.

Abstract: An imaging member can be prepared by imagewise application of a mixture of a sol precursor in a liquid to a suitable substrate. Application is preferably accomplished by ink jet printing. Upon removal of the liquid, such as by drying, an insoluble, crosslinked polymeric sol-gel matrix is formed that will accept a lithographic printing ink. The resulting imaging member can be used for lithographic printing.

Abstract: To delete undesired ink-receptive areas on a wet lithographic printing construction, an oleophobic material is applied to the hydrophilic surface of the plate that has suffered contamination and/or scratching, and allowed to cure. So long as the hydrophilic surface is capable of permanently bonding the oleophobic deletion agent, the areas to which that agent has been applied will not accept ink.

Abstract: A printing plate for use in lithographic printing has a thermally responsive recording material. A plate is fabricated with a photosensitive emulsion affixed to an upper surface of an aluminum substrate. The plate is first chemically processed so that it is capable of accepting ink (i.e., oleophilic). Thereafter, selected areas of the emulsion are thermally removed, preferably by exposure to a high power laser beam. The plate is ready for immersion into an aqueous ink solution.