Abstract: The present invention provides a resin composition that includes (A) a polymer compound that has, on a side chain of a main chain polymer, through a linkage group containing a hydrogen-bonding group and a ring structure, a terminal ethylenic unsaturated bond, and is soluble or swelling in water or an alkali aqueous solution, and (B) a compound that generates radicals when exposed to light or heat. The invention further provides a thermo/photosensitive composition that includes (A′) a polymer compound that has a non-acidic hydrogen-bonding group on a side chain and is soluble or swelling in water or an alkali aqueous solution, and (B′) a compound that generates radicals when exposed to light or heat.

Abstract: A printing plate has a photosensitive layer (3) including a photocatalyst formed on a strip-shaped windable substrate (1) with or without another layer (2) interposed so that the printing plate is wound into a roll shape. An unused portion is extracted from the printing plate roll (8A) each time of replacement of a printing plate and an image can be formed on the unused portion whereupon printing plate replacement is realized without regenerating of the printing plate.

Abstract: An off-press plate-making apparatus is provided which comprises an apparatus for removing the lithographic image from the substrate of a used printing master and an apparatus for recoating the recycled substrate with a new image-recording layer. The off-press cleaning and recoating of the substrate provides a short press down-time. The recoated substrate forms an imaging material which can be exposed either on-press in a digital press comprising an integrated exposure apparatus or off-press in an exposure apparatus, which can be integrated in the plate-making apparatus or mechanically coupled thereto.

Abstract: A variable data lithographic printing device comprises surrounding a printing cylinder a photosensitive layer coater, an exposure source, optionally a developer, an inking applicator, optionally a transfer system, and optionally an eraser. During printing operation, each surface areas of the rotating cylinder continuously undergo the cycle of coating, imagewise exposure, optionally developing, inking, printing of inked images to the receiving medium, and optionally erasing processes. The developing means can be omitted if an ink and/or fountain solution developable photosensitive layer is used. In an alternative design, the cylinder is replaced with a continuous supply of a ribbon with lithographic substrate surface. In another alternative design, the cylinder and the coater are replaced with a continuous supply of a pre-sensitized ribbon comprising on a substrate a photosensitive layer.

Abstract: A method for modifying an image surface of a printing plate includes identifying a location of a pixel of an image at the image surface, an ink being disposed at the location of the pixel. The ink at the location of the pixel is then irradiated using a laser imaging system. The ink may be cured by the radiation so that it is hardened and useable to receive liquid ink and be used as a printing surface. The ink may be ablated and removed. Individual pixels of the image may be added or removed from the printing surface.

Abstract: At printing time, a blanket cylinder gear is meshed with a plate cylinder gear, whereby a first plate cylinder is rotatable by a drive motor. At image-recording time, the blanket cylinder gear is separated from the plate cylinder gear. In this state, a different motor drives the plate cylinder gear to rotate the first plate cylinder at low speed.

Abstract: The presence of unwanted ink-receptive sections on developed positive-working lithographic plates due to shading by plate-holding clamps during imaging, is avoided by the use of clamps that are substantially transparent to the imaging radiation. In the case where the plate precursors can be imaged by heat, the presence of unwanted unexposed sections can also be avoided by selectively heating those sections shaded by the clamps, while avoiding heating the image section of the plate.

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: 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: Lithographic printing form precursors comprising positive working polymeric coatings on substrates may during storage or transportation undergo undesirable changes in their imaging properties. It has been found that acceptable properties can be restored by carrying out a heat treatment which involves a relatively short heating stage followed by accelerated cooling.

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: The present invention relates to a negative-working radiation imageable lithographic printing plate precursor, preferably having only two polymeric layers on a support. The first (bottom) layer is composed of oleophilic polymers and a photothermal converter which converts radiation to heat. The second polymeric layer (top) is composed of crosslinked hydrophilic polymers which absorb aqueous fountain solution and repel ink. The oleophilic polymers in the first layer contain functional groups are interlayer chemically bonded to the hydrophilic polymer in the second layer to provide interlayer adhesive bonding between the two layers. The plate is imagewise exposed to radiation, such as with an IR laser, resulting in non-ablative adhesion-weakening between the two layers so that the plate can be developed by fountain solution and/or ink on press whereby the top layer in the exposed area is removed on the press to reveal the ink-receptive image area.

Abstract: A printing plate for computer-to plate lithography having a metal substrate with an anodized surface portion. The anodized surface portion has a porous texture in which a radiation-absorbing composition, preferably a black dye, is deposited. The surface portion with the radiation-absorbing composition is covered with a hydrophilic polymer or a sealant both. Upon exposure to laser radiation, the underlying oleophilic anodized surface portion containing the radiation-absorbing composition is revealed. Alternatively, laser radiation of the polymer composition may cause the affinity of the polymer for water and ink to change so that an irradiated portion of the polymer becomes oleophilic while the non-irradiated portion remains hydrophilic.

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: Disclosed is a printing plate precursor comprising an aluminum support having been subjected to surface roughening treatment and then to anodizing treatment, and provided thereon, a component layer comprising an image formation layer containing heat melting particles or heat fusible particles, the support satisfying the following conditions (a) and (b):

Abstract: The present invention provides a method and apparatus for applying a coating material onto a print substrate mounted on a plate cylinder of a printing press. The method comprising: delivering a supply of the coating material to a distributive surface of an ultrasonic horn, the distributive surface controlling a flow of the coating material to an active edge of the ultrasonic horn, and atomizing the coating material at the active edge of the ultrasonic horn and directing the atomized coating material onto a surface of the print substrate. The present invention also provides a multi-purpose ultrasonic acoustic coating/cleaning system for applying a coating material onto, and cleaning the coating material from, a print substrate.

Abstract: A heat-sensitive lithographic printing plate precursor is disclosed which comprises a hydrophilic support and a coating provided thereon, wherein the coating comprises an infrared light absorbing cyanine dye, the dye containing a bridged methine chain and from three to five groups which are anionic or which become anionic in an aqueous alkaline solution having a pH of at least 9. Such dyes provide high sensitivity and low dye stain after processing.

Abstract: A process for treating a used or unused printing plate with an erasing composition to clean the printing plate, laser imaging the printing plate with a polymeric substance, and to provide art image thereon, and fixing the image on the printing plate. Further, the printing plate has applied thereto any one of a heat-curable and water-soluble substance, if desired, immediately after the laser imaging, or a water-soluble substance immediately after the laser imaging, followed by warming of the printing plate. The water-soluble substance or the heat-curable and water-soluble substance is washed off using a solution essentially consisting of water before printing.

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: There is prepared a printing plate on which a material being hydrophilic at a first temperature and being hydrophobic at a second temperature which is lower than the first temperature is provided. First, the whole surface of the printing plate is forcibly made either one of hydrophobic or hydrophilic. Next, a region having the other nature out of hydrophobic and hydrophilic is formed so as to correspond to an image to be printed. Then, ink is supplied onto the region having hydrophobic nature to conduct offset printing.

Abstract: A direct-to-plate method of lithographic printing is disclosed wherein a printing press is used that is coupled to a coating apparatus and to a cleaning apparatus; wherein the coating apparatus applies an image-recording layer on a substrate so as to obtain a printing plate, which is mechanically transferred to the printing press; and wherein, after the print job, the printing plate is mechanically transferred to the cleaning apparatus wherein the substrate is recycled, so that the recycled substrated can be reused in a next cycle of coating, printing and cleaning. The off-press coating and the off-press cleaning step provide a fully automated printing method wherein the press down-time is minimized. The method comprises also an off-press or an on-press exposure step.

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: Provided is a plate-making method for producing a waterless lithographic printing plate, wherein the method comprises: (I) an exposing step of imagewise exposure of the precursor with a laser with a controlled condition that a portion of a laser-exposed area in a photo-thermal conversion layer in the precursor remains in the photo-thermal conversion layer of the finished printing plate, and (II) a developing step of removing a silicone rubber layer in the laser-exposed area to form an image on the printing plate. The precursor to be processed comprises (A) a support, (B) an undercoat layer formed by applying onto the support a coating liquid that contains a water-soluble or water-dispersible polymer and water as a solvent, and then drying the coating liquid, (C) a photo-thermal conversion layer which comprises polyurethane and a photo-thermal converting agent; and (D) a silicone rubber layer, laminated in that order.

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 method for imaging patterning compositions comprising the steps of: (1) providing at least one patterning composition layer on a substrate; said patterning composition comprising: (a) at least one acid generator; (b) at least one cross linking resin or compound; (c) at least one binder resin comprising a polymer containing reactive pendant group selected from group consisting of hydroxyl, carboxylic acid, sulfonamide, active imide, alkoxymethylamides and mixtures thereof; and (d) at least one infrared absorber; (2) imagewise exposing the patterning composition layer to actinic radiation; (3) treating the imaged patterning composition layer with heat energy to treat the imaged portions of the composition layer; (4) flood exposing the heat-treated, imaged patterning composition layer with UV light for a predetermined time, said time being sufficient to promote the effective clear-out of non-imaged portions during the developing step without causing substantial deterioration of the imaged portions; and

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 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: The invention relates to an apparatus for image formation on cylindrical surfaces of printing machines. The object of the invention is to provide a compact image formation unit with a broad application rage regarding its usage, the sequence in time and variation in time of the process steps. The invention accomplishes this by processing units mounted on slides movable separately on a common cross bar. Each slide carries at least one processing unit. The cross bar is located in a gusset area between a plate cylinder and a blanket cylinder.

Abstract: A first structural unit includes a laser image-setting head, and a second structural unit includes a loading compartment to accommodate a cassette housing having a thermal transfer ribbon on spools having hubs. After a cassette is inserted in the loading compartment, the compartment is closed so that drive rollers engage the hubs without play. To produce a printing plate, the second structural unit is then brought over the first structural unit in the manner of a telescope by a moving device, and the thermal transfer ribbon is brought to the laser image-setting head. The thermal transfer ribbon inserted into the loading compartment is guided by self-centering means so that it does not contact the cassette housing, and is positioned with respect to the plate cylinder by guide rollers. Wear-free and therefore fast ribbon guidance can be performed, and automation of the movement sequences of the thermal transfer ribbon can be achieved.

Abstract: An imaging member, such as a negative-working printing plate or on-press cylinder, comprises latex polymer-carbon black composite particles. Such imaging members can be prepared with a hydrophilic imaging layer comprised of a heat-sensitive hydrophilic polymer having ionic moieties and the latex polymer-carbon black composite particles as a photothermal conversion material. The latex polymer-carbon black composite particles can be formulated in water or water-miscible solvents without agglomeration with other components such as charged polymers.

Abstract: A printing method is disclosed wherein a grained and anodized aluminum support is coated with an image recording layer comprising hydrophobic thermoplastic polymer particles. The heat-sensitive imaging material thus obtained is then image-wise exposed and processed, thereby obtaining a material having a lithographic image which consists of hydrophobic printing areas on a hydrophilic support and which is used as a printing master in a printing press. After the press run, the lithographic support is recycled by removing the hydrophobic printing areas from the hydrophilic surface of the aluminum support. The recycled support is then reused in a next cycle of coating, exposing, processing and printing. By using a grained and anodized aluminum support having a hydrophilic surface with a surface roughness, expressed as arithmetical mean center-line roughness Ra, which is less than 0.45 &mgr;m, the run length of the printing master is improved.

Abstract: The invention provides a method for making a lithographic printing surface using media with coalescence inhibitor. The lithographic printing surface is made on a hydrophilic surface using a radiation sensitive medium that comprises hydrophobic polymer particles in an aqueous medium, a substance for converting light into heat, and a coalescence inhibitor. The lithographic printing surface made by the method of this invention may be used for printing long run lengths on lower quality paper and in the presence of press-room chemicals. The method allows for on-press imaging and development of the lithographic printing surface. The radiation sensitive medium can also be sprayed onto a hydrophilic surface to create a lithographic printing surface that may be processed wholly on-press. It can also be processed in the more conventional fully off-press fashion.

Abstract: A method of making a negative-working heat-sensitive lithographic printing plate precursor is disclosed, the method comprising the steps of (a) preparing an aqueous dispersion comprising particles of a hydrophobic thermoplastic polymer A which is not soluble or swellable in an aqueous alkaline developer and particles of a polymer B which is soluble or swellable in an aqueous alkaline developer but not soluble or swellable in water, wherein the glass transition temperature of polymer A is higher than the softening temperature of polymer B; (b) applying the aqueous dispersion on a lithographic substrate having a hydrophilic surface, thereby obtaining an image-recording layer; (c) overall heating the image-recording layer at a temperature which is higher than the softening temperature of polymer B without inducing coalescense of the particles of polymer A. The printing plate precursor has improved mechanical resistance.

Abstract: An improved offset printing press has a single plate blanket image (PBI) cylinder for holding an image formed on a thin film printing plate affixed thereto. The plate may be from 0.5 to 25 microns thick and has a thin layer of ink repelling material coated thereon. The plate is imaged, after being affixed to the PBI cylinder, by ablating selective portions of the ink repelling coating. The PBI cylinder is constructed to hold the printing plate by vacuum techniques, and apparatus to load and unload the plate is associated with the PBI cylinder. Because of the thinness of the printing plate, the PBI cylinder is a compliant surface, capable of printing on an inelastic media covered impression cylinder. In addition, unique inking apparatus is provided to transfer ink to the imaged printing plate. Variations of the press include a four color press utilizing a single PBI cylinder.

Abstract: A negative-working lithographic printing plate precursor is disclosed which comprises a grained and anodized aluminum support having a hydrophilic surface and a heat-sensitive coating provided on the hydrophilic surface, the coating comprising hydrophobic thermoplastic polymer particles which are capable of forming a hydrophobic phase in the coating by heat-induced coalescence of the polymer particles. The support is characterized by a surface roughness, expressed as arithmetical mean center-line roughness Ra, which is less than 0.45 &mgr;m. The smooth surface enables to prepare a lithographic printing plate from the mentioned precursor, which is characterized by a high run length during printing.

Abstract: The invention relates to an apparatus for imaging surfaces in printing presses, whereby the surfaces to be imaged contains image information of the preceding printing job. The apparatus allows a fast and low-cost regeneration of surfaces carrying image information in printing presses. The apparatus comprises at least one printing form cylinder, a disengageable inking unit, and a movable imaging unit having an image creation unit for applying image information to image and non-image carrying layers on the surface. The imaging unit has an erasing unit preceding the movable imaging unit in the moving direction.

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 making a reusable printing plate in which a hydrophobic image area is formed on a hydrophilic plate surface containing a photocatalyst. The method includes the steps of carrying out a hydrophobic agent application process in which a solution containing an organic compound having a property of reacting with the plate surface by a heating process and a property of being decomposed by the action of the photocatalyst when irradiated by light having a higher energy than a band gap energy of the photocatalyst is applied on the plate surface; carrying out an image area formation process in which a part of the plate surface is subjected to a heating process to form a hydrophobic image area; and carrying out a non-image area formation process in which the organic compound applied to an area other than the hydrophobic image area on the plate surface is removed.

Abstract: Multi-layer, negative working imageable elements useful as lithographic printing plate precursors are disclosed. The elements contain, in order, a support; an underlayer; and an imageable layer. The imageable layer comprises a negative working imageable composition; and the underlayer is soluble or dispersible in a developer. Elements that can be imaged with ultraviolet or visible radiation and elements that can be imaged with infrared radiation or with heat are disclosed.

Abstract: An image forming method using a negative type image forming material is disclosed, and said method comprises the steps of exposing a negative type image forming material to infrared laser imagewise, which image forming material comprises a substrate and an image recording layer formed thereon, comprising (A) a radical generator, (B) a radical-polymerizable compound, (C) an infrared absorbing agent, and (D) a binder polymer; and developing the image forming material with an alkaline developing solution comprising a weak acid or a salt thereof having a dissociation constant pka of from 10 to 13.

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: 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: A lithographic printing precursor for lithographic offset printing comprises, a layer of imageable medium on a hydrophilic base. The imageable medium comprises hydrophobic polymer particles in an aqueous medium, a substance for converting light into heat, and a non-crosslinkable aqueous-soluble composition. The lithographic printing precursor may be used to make lithographic printing surfaces that obtain long run lengths on lower quality paper and in the presence of press-room chemicals. The lithographic printing precursor can be imaged and developed on-press and the imageable medium can also be sprayed onto a hydrophilic surface to create a printing surface that may be processed wholly on-press. It can also be processed in the more conventional fully off-press fashion. The hydrophilic surface can be a printing plate substrate or the printing cylinder of a printing press or a sleeve around the printing cylinder of a printing press. The cylinder can be conventional or seamless.

Abstract: A negative planographic printing plate precursor for heat-mode exposure systems, which has, on a support, a photosensitive layer containing: (A) a light-to-heat conversion agent; (B) a polymerizable unsaturated group-having compound; and (C) an onium salt having a counter anion with a valency of at least 2. The precursor is capable of being exposed with an IR laser for image formation thereon. The onium salt may be, for example, a diazonium salt, iodonium salt or sulfonium salt. The counter anion has at least two anionic sites which may be the same or different, and the anionic structure is preferably divalent to hexavalent.

Abstract: A negative-working heat-sensitive material for making a lithographic printing plate by direct-to-plate recording is disclosed which comprises in the order given a lithographic base having a hydrophilic surface, an oleophilic imaging layer and a cross-linked hydrophilic upper layer, characterize in that the oleophilic imaging layer comprises at least one transition metal complex of an organic acid. Materials according to the invention are characterized by an increased run length and can be used as a printing plate immediately after exposure.

Abstract: A printing press includes a blanket cleaning controller, automatic plate change unit, image exposing section, pre-inking controller, and CPU. The blanket cleaning controller cleans a blanket mounted on a blanket cylinder. The automatic plate change unit changes a printing plate mounted on a plate cylinder to a new printing plate. The image exposing section exposes an image on the printing plate mounted on the plate cylinder. The pre-inking controller forms, on an ink roller group, an ink film thickness distribution corresponding to an image to be exposed next. The CPU automatically drives the blanket cleaning controller, automatic plate change unit, image exposing section, and pre-inking controller in an operation order set by a start command.

Abstract: The invention provides a negative image recording material comprising: a support and an image recording layer disposed on the support, the image recording layer comprising an amide-acid compound containing a carboxyl group and an amide group expressed by the following General Formula (1): 1

Abstract: Methods of manufacturing multi-layer thermally imageable elements useful as lithographic printing plate precursors are disclosed. The elements comprise a substrate, an underlayer, and an imageable layer. The imageable layer comprises a first polymeric material and o-diazonaphthoquinone containing material. After the underlayer has been coated over the substrate and the imageable layer has been coated over the underlayer, the element is heated to between about 130° C. and about 200° C. for a time sufficient to decrease the sensitivity of the imageable element to the white light.

Abstract: Lithographic printing form precursors comprising positive working polymeric coatings on substrates may during storage or transportation undergo undesirable changes in their imaging properties. It has been found that acceptable properties can be restored by carrying out a heat treatment which involves a relatively short heating stage followed by accelerated cooling.

Abstract: The present invention provides a photosensitive composition for an infrared laser used for direct plate making, which has high sensitivity and good developing latitude and storage stability, and provides a planographic printing plate in which this composition is used. The positive-type photosensitive composition of the present invention has (a) a macromolecular compound having alkali-soluble groups and (b) a compound that has a phthalocyanine skeleton and has in its molecule at least one group which can form a bond by interaction with an alkali-soluble group in the macromolecular compound (a).