Abstract: The present invention provides a lithographic printing plate precursor which exhibits satisfactory ink cleanup and restart toning characteristics during printing.

Abstract: To provide a lithographic printing plate precursor which is excellent in the gum development property, running processing property and scratch resistance and a lithographic printing plate precursor which is good in all performances of the on-press development property, ink receptivity, sensitivity and printing durability, and a method of producing thereof. A lithographic printing plate precursor has a support, an image-recording layer containing a radical polymerization initiator and a radical polymerizable compound, and an overcoat layer containing a polymer resin which has a cloud point in an aqueous solution and includes a monomer unit containing at least any of an amino group and an amido bond, in this order.

Abstract: Provided is a method of producing a planographic printing plate, including: subjecting a planographic printing plate precursor, to image-wise exposure; and developing it using an alkaline aqueous solution which contains a specific compound and has a pH of from 8.5 to 10.8, in this order. The recording layer has: a lower layer containing a water-insoluble and alkali-soluble resin and an infrared ray absorbing agent; and an upper layer containing a water-insoluble and alkali-soluble polyurethane resin and a polyorganosiloxane. The specific compound is a nonionic or anionic surfactant, or at least one compound represented by Formula (1) or (2), wherein R11, R12, and R13 each represent an alkyl group; R14 represents an alkylene group; and R15 represents a single bond or a divalent linking group containing a hetero atom; and R21, R22, and R23 each represent an alkyl group.

Abstract: A lithographic printing plate precursor includes a support, and an image-recording layer, the image-recording layer contains a urethane resin having a polyalkylene oxide chain represented by the formula (1) as defined herein in a side chain, an infrared absorbing agent, a radical polymerizable compound and a radical polymerization initiator, and an unexposed area of the image-recording layer is capable of being removed with at least one of dampening water and ink.

Abstract: A method of making a relief image printing element from a photosensitive printing blank is provided. The method comprising the steps of: 1) providing a photosensitive printing blank comprising a backing layer, at least one layer of photoresin on top of the backing layer and a removable coversheet on top of the at least one layer of photoresin; 2) imaging the photosensitive printing blank through the removable coversheet using a laser to create a relief image therein; and 3) removing the removable coversheet.

Abstract: A method of tailoring the shape of a plurality of relief printing dots created in a photosensitive printing blank during a platemaking process is provided. The photocurable layer is exposed to actinic radiation using an array of UV LED light assemblies and the use of the array of UV LED light assemblies produces relief printing dots having at least one geometric characteristic selected from the group consisting of a desired planarity of a top surface of the relief printing dots, a desired shoulder angle of the relief printing dots and a desired edge sharpness of the relief printing dots.

Abstract: A method for producing a printable lithographic plate from a negative working, radiation imageable plate having an oleophilic resin coating that reacts to radiation by cross linking and is non-ionically adhered to a hydrophilic substrate. Steps include imagewise radiation exposing the coating to produce an imaged plate having partially reacted image areas including unreacted coating material, and completely unreacted nonimage areas; developing the plate by removing only the unreacted, nonimage areas from the substrate while retaining unreacted material in the image areas; and blanket exposing the developed plate with a source of energy which further reacts the retained unreacted material in the image areas. A plate with a coating containing resin particles can be imaged to produce initial cross-linking, then mechanically developed. Hardening of the imaged areas is completed with a relatively intense post-heating at 160 deg. C., which further cross links the monomer and fuses the resin particles.

Abstract: A lithographic printing plate precursor is provided that exhibits less blooming without using a specific polymerization initiator, infrared radiation absorbing agent and the like. The lithographic printing plate precursor comprises a substrate having thereon an image forming layer comprising a radiation-sensitive composition which comprises a radical polymerizable component, an infrared radiation absorbing agent and a radical polymerization initiator, wherein the radiation-sensitive composition comprises a fluorinated copolymer substantially having no hydrophilic moiety.

Abstract: A lithographic printing plate precursor comprising a coating provided on a support having a hydrophilic surface, the coating containing thermoplastic polymer particles and an IR-dye characterized in that the IR-dye contains a structural element according to Formula I wherein A represents hydrogen, halogen or a monovalent organic group; Y and Y? independently represent —CH— or —N—; R1 and R2 independently represent hydrogen, an optionally substituted alkyl or aryl group or represent the necessary atoms to form a ring; * represents the linking positions to the rest of the molecule.

Abstract: A lithographic printing plate precursor in a positive-type with an infrared-sensitivity, having a support and an image recording layer provided on the support, the support having a hydrophilic surface, the recording layer having a particular resin, an amphoteric surfactant and/or an anionic surfactant, and an infrared absorbing agent, wherein the particular resin being at least one of resins selected from the group consisting of a polyurethane resin, a poly (vinyl acetal) resin, and maleimide resin A.

Abstract: A positive-working lithographic printing plate precursor is disclosed which comprises on a support having a hydrophilic surface or which is provided with a hydrophilic layer a heat and/or light-sensitive coating including an infrared absorbing agent and a compound including a benzoxazine group.

Abstract: A processing solution is used to provide flexographic relief printing plates. This solution includes diisopropylbenzene, and one or more organic co-solvents, at least one of which is an aliphatic dibasic acid ester. The processing solution may also include one or more alcohols as co-solvents.

Abstract: A method of preparing a photosensitive printing blank, the method comprising the steps of: a) coating a slip film onto a coversheet and drying the slip film; and depositing at least one layer of photosensitive material on top of the slip film coated coversheet and laminating a substrate layer to the exposed surface of the photosensitive material. The slip film comprises: i) a polymer selected from the group consisting of polystyrene and polyvinylpyrrolidone; ii) optionally, an additive. The slip film at least substantially eliminates the formation of hot spots during an analog plate making process.

Abstract: A method for producing a planographic printing plate, including the steps of: image-wise exposing a positive type planographic printing plate precursor including an intermediate layer and a positive type image-forming layer successively on a support, the intermediate layer having a coating amount after drying of from 2 mg/m2 to 200 mg/m2 and including a polymer including a repeating unit represented by the following formula (I-1) and a repeating unit represented by the following formula (I-2); and developing the exposed positive type planographic printing plate precursor using a treatment liquid having a pH of from 7 to 12:

Abstract: A lithographic printing plate precursor includes a support and one or more layers, one of the one or more layers is a photosensitive layer containing an initiator compound, a polymerizable compound and a binder polymer, and a layer being in contact with the support of the one or more layers contains a copolymer containing a repeating unit having a zwitterionic structure and a repeating unit having a structure capable of interacting with a surface of the support.

Abstract: A radiation sensitive composition which is primarily sensitive in the near UV and visible region of the electromagnetic spectrum is composed of a polymeric binder, an ethylenically unsaturated monomer, a radiation absorbing compound, a photoaccelerator, an onium compound, and an adhesion promoter, which are overcoated with an oxygen barrier layer. When applied to the proper support and processed, the composition is useful as an offset lithographic printing plate, color proofing film or image resist.

Abstract: A method of making a relief printing element in a liquid photopolymer platemaking process is described. The method comprises the steps of: (a) selectively exposing the liquid photopolymer to actinic radiation through a negative to crosslink and cure portions of the liquid photopolymer; and (b) reclaiming uncured portions of the liquid photopolymer to be reused in the platemaking process. The step of reclaiming uncured portions of the liquid photopolymer comprises (i) heating the printing element to decrease the viscosity of the uncured liquid photopolymer; and (ii) removing uncured liquid photopolymer from the surface of the relief image printing element so that recovery of uncured liquid photopolymer from the surface of the relief image printing element is enhanced.

Abstract: An aluminum-containing substrate can be provided for use in lithographic printing plate precursors. Before radiation-sensitive layers are applied, a grained and sulfuric acid anodized aluminum-containing support is treated with an alkaline or acidic pore-widening solution to provide its outer surface with columnar pores. The diameter of the columnar pores at their outermost surface is at least 90% of the average diameter of the columnar pores. Directly on this treated surface, a hydrophilic layer is applied, which hydrophilic layer contains a non-crosslinked hydrophilic polymer having carboxylic acid side chains.

Abstract: An infrared sensitive and chemical treatment free photosensitive composition, includes, based on weight percentage, 30-70% of a water soluble thermally cross-linking resin, 1-20% of a water-soluble photocross-linking polymerized resin, 10-50% of a photopolymerizable oligomer, 1-30% of a multifunctional monomer, 1-20% of a cationic photopolymerization initiator, and 1-20% of an infrared irradiation absorption dye. The photosensitive composition of the present invention is useful for preparation of an infrared sensitive and chemical treatment free lithographic plate. The lithographic plate of the present invention has a high sensitivity and a good mesh point reduction, and after exposure to an infrared light source, can be printed directly after being washed with tapped water or without any washing and processing step, and has a long run length.

Abstract: A lithographic printing plate precursor includes, in the following order: a support; an image-recording layer which is capable of forming an image by removing an unexposed area by an automatic development processor in the presence of a developer having pH of from 2 to 14 after exposure and contains (A) a sensitizing dye, (B) a polymerization initiator, (C) a polymerizable compound and (D) a polymer which is insoluble in water and alkali-soluble; and a protective layer, and the protective layer contains (E) a hydrophilic polymer which has a repeating unit represented by the formula (1) as defined herein and a repeating unit represented by the formula (2) as defined herein and a sum of the repeating unit represented by the formula (1) and the repeating unit represented by the formula (2) is at least 95% by mole based on total repeating units constituting the polymer.

Abstract: A lithographic printing plate precursor includes an image-recording layer and a protective layer containing a stratiform compound, wherein at least one of the image-recording layer and the protective layer contains a polymer containing as a repeating unit, a structural unit having an ammonium structure.

Abstract: The present invention relates a printing element comprising at least one polymer layer which has photoimageable constituents and additions to make the polymer layer either hydrophobic or hydrophilic.

Abstract: On-press developable, negative-working lithographic printing plate precursors have a sulfuric acid anodized aluminum-containing substrate in which the oxide layer pores have been widened using an acidic or alkaline treatment. Over the widened pores, a hydrophilic coating is applied, which coating comprises a non-crosslinked hydrophilic polymer having carboxylic acid side chains. This particular substrate provides improved adhesion and printing durability for on-press development and printing.

Abstract: A photosensitive resin composition for flexographic printing having excellent resistance to an ink comprising an organic solvent and an emulsion ink used in flexographic printing, for example, a UV-curable ink or an ink using a vegetable oil or light naphtha and having excellent suitability for printing applications such as image reproducibility and print durability. The photosensitive resin composition for flexographic printing includes, at least, (a) one or more thermoplastic elastomers, (b) an acrylic-terminated liquid polybutadiene containing 1,2-bonds in an amount of 80% or more, (c) a photopolymerizable unsaturated monomer having at least one or more ethylenically unsaturated groups, and (d) a photopolymerization initiator.

Abstract: a method for preparing a lithographic printing plate that includes imagewise exposing a lithographic printing plate precursor comprising a coating provided on a support having a hydrophilic surface, the coating containing thermoplastic polymer particles and an infrared radiation absorbing dye characterized in that the coating further comprises a phenolic stabilizer.

Abstract: Embodiments of the present invention involve three-layer printing members having a central layer that is non-conductive yet abalatable at commercially realistic fluence levels. In various embodiments, the central layer is polymeric with a dispersion of nonconductive carbon black particles therein at a loading level sufficient to provide at least partial layer ablatability and water compatibility of the resulting ablation debris.

Abstract: Negative-working lithographic printing plate precursor a negative-working imagable layer and an outermost water-soluble overcoat layer that is disposed directly on the negative-working imagable layer. The outermost water-soluble overcoat layer comprises: (1) one or more film-forming water-soluble polymeric binders, and (2) organic wax particles dispersed therein. The organic wax particles have an average largest dimension of at least 0.05 ?m and up to and including 0.7 ?m, as determined from a scanning electron micrographic of the dried outermost water-soluble overcoat layer. Useful organic wax particles include fluorinated or non-fluorinated hydrocarbon wax particles.

Abstract: A method of making a relief image printing element having a relief pattern comprising a plurality of relief dots, wherein the photocurable printing blank comprises a backing layer having at least one photocurable layer disposed thereon and a masking layer on the at least one photocurable layer is provided. The method comprising the steps of: a) selectively ablating the masking layer to create an overall image in the masking layer, such that the overall image comprises a sub-image, comprising a pattern of cells, in it; b) applying an oxygen barrier layer on top of the masking layer; c) exposing the printing element to actinic radiation through the oxygen barrier layer and the masking layer; and d) developing the printing blank by removing the barrier layer and the uncured portions of the photocurable layer to reveal the relief image.

Abstract: A variable lithographic printing process includes absorbing a release agent into an imaging member; forming a later image by evaporating the release agent from selective locations on an imaging member surface; developing the latent image; and transferring the developed image to a receiving substrate. The release agent diffuses through the imaging member surface.

Abstract: A resin composition for laser engraving is provided that includes (Component A) a compound having a hydrolyzable silyl group and/or a silanol group, (Component B) a depolymerization catalyst and/or a depolymerization catalyst precursor, and (Component C) a depolymerizable binder polymer.

Abstract: Electrochemically grained and anodized aluminum supports are treated with a post-treatment coating solution containing a polymer derived at least in part from vinyl phosphonic acid and phosphoric acid. This post-treated support is useful as substrates in the preparation of lithographic printing plate precursors. The post-treatment substrate treatment enables wide latitude in manufacturing and compatibility with silicate-free developers to achieve negligible background staining and oxide attack.

Abstract: A method of thermally developing photocurable printing blank to produce a relief pattern comprising a plurality of relief dots. The photocurable printing blank comprises a backing layer having at least one photocurable layer disposed thereon and a laser ablatable mask layer disposed on top of the at least one photocurable layer. The method includes the steps of (1) imaging the at least one photocurable layer by ablating portions of the laser ablatable mask layer; (2) laminating an oxygen barrier membrane to a top of the laser ablated mask layer; (3) exposing the printing blank to actinic radiation through the oxygen barrier membrane and mask layer to actinic radiation, thereby creating the relief pattern; (4) removing the oxygen barrier membrane; and (5) thermally developing the printing blank to remove the laser ablated mask layer and uncured portions of the photocurable layer and reveal the relief pattern. The presence of the oxygen harrier membrane produces printing dots having desired characteristics.

Abstract: A method is described for producing an imaged lithographic printing plate, wherein the developer comprises a hydrophilic polymer which comprises (m1) primary, secondary and/or tertiary amino groups, and (m2) acid groups selected from —COOH, —SO3H, —PO2H and —PO3H2, and (m3) optionally alkylene oxide units —(CHR1—CH2—O)p—, wherein R1 is H or —CH3 and p is an integer from 1 to 50.

Abstract: A printing plate precursor for laser engraving, including a relief forming layer including a cured resin material formed by thermally crosslinking a resin composition including at least (A) non-porous inorganic particles, (B) a binder polymer having a glass transition temperature (Tg) of 20° C. or higher, and (C) a crosslinking agent.

Abstract: Embodiments of the present invention involve printing members that utilize a particle-fusion imaging mechanism but avoid susceptibility to handling damage. In particular, printing plates in accordance with the invention may utilize two phases, and these may originate, during manufacture, as two particle systems. Both systems are initially dispersed in a single coating applied as a layer, or in multiple coatings applied as adjacent layers, on a substrate. The second particle system exhibits a glass-transition or thermal coalescing temperature well above room temperature and also above the temperature at which the coating is dried. The coalescing temperature of the first particle system is below the drying temperature. As a result, when the coating is dried, the first particle system coalesces and forms a binder that entrains the second particle system, which has not coalesced.

Abstract: A positive-working lithographic printing plate precursor has an outermost imageable layer that is present at a dry coverage weight of at least 0.7 g/m2 and up to and including 1.6 g/m2 and comprises a primary polymeric binder comprising recurring units of a hydroxyaryl acetal or a hydroxyaryl ester, or recurring units of both a hydroxyaryl acetal and a hydroxyaryl ester. The outermost imageable layer also contains an alkali-soluble secondary vinyl polymer that is not a primary polymeric binder and a non-polymeric polyhydric phenol. These precursors comprise an infrared radiation absorber to make them sensitive and imageable using infrared radiation. After imaging, the precursors can be processed (developed) using an relatively low pH developer such as a silicate- or metasilicate-free developer.

Abstract: The invention provides an ink composition having at least (A) a polymerization initiator, (B) an ester or amide of (meth)acrylic acid having a 1,3-dioxolane ring skeleton or a 1,3-dioxane ring skeleton or (B?) an ester or amide of (meth)acrylic acid having a 1,3-diketone structure, and (C) a colorant. The invention further provides an inkjet recording method and a method for producing a planographic printing plate, each of which includes at least (I) ejecting the ink composition onto a hydrophilic support and (II) curing the ink composition by irradiating the ejected ink composition with active radiation so as to form a hydrophobic image region on the hydrophilic support. The invention furthermore provides a planographic printing plate formed by the method for producing a planographic printing plate.

Abstract: Negative-Working Lithographic Printing Plate Precursors can be provided with desired contrast coloration after imaging using a coloring fluid that includes a water-insoluble colorant that is soluble in a water-insoluble fatty alcohol. The coloring fluid provides an optical density change in the exposed regions of at least OD2 that is greater than the original optical density of those regions, OD1. The coloring fluid can be applied immediately after imaging and before processing, or it can be applied as part of the developer or processing solution, or it can be applied after processing. The coloring fluid can also be applied to imaged precursors that are designed for either off-press or on-press development.

Abstract: A lithographic printing plate precursor includes: a support; and an image-recording layer containing (A) a polymerization initiator, (B) a sensitizing dye and (C) a polymerizable compound, and the image-recording layer or an undercoat layer which is optionally provided between the support and the image-recording layer comprises (D) a polymer compound comprising (a1) a repeating unit having a side chain having a structure represented by the following formula (a1-1) and (a2) a repeating unit having a side chain having at least one structure of the formulae (a2-1), (a2-2), (a2-3), (a2-4), (a2-5) and (a2-6) as defined herein.

Abstract: The invention provides a near infrared absorption polymer comprising at least two different pendent infra-red chromophoric moieties covalently bonded to the backbone of an alkali-soluble resin, at least one of which is an indole cyanine dye and the other of which is a benz[e]-indole cyanine dye. When used in the coating of a heat sensitive positive working lithographic printing plate precursor the stabilization time needed after manufacture is significantly reduced, avoiding further conditioning processes before use. The precursors are preferably imagewise exposed with a near-infrared laser emitting at between 780 nm and 850 nm.

Abstract: A process for making a lithographic printing plate, comprising: an exposure step of imagewise exposing a lithographic printing plate precursor that comprises, above a hydrophilic support, a photosensitive layer comprising (A) a compound that generates a radical upon the application of light or heat, (B) a polymer having an aromatic carboxy group in a side chain, (C) a polymerizable compound, and (D) an infrared absorber; and a development processing step using one type of processing liquid, wherein the processing liquid has a pH of 8.5 to 10.8.

Abstract: An infrared sensitive, positive-working, image forming composition and element are disclosed. The image forming composition comprises a 1,1-di[(alkylphenoxy)ethoxy]cyclohexane, an infrared absorbing dye having a maximum absorption peak in the range of from about 700 nm to about 1100 nm, and a novolac polymer. The composition is applied and dried on a planar, hydrophilic substrate to form an image forming element, in particular, a planographic printing plate. Upon imagewise exposure to a near-infrared radiation source, the infrared dye absorbs light in the exposed areas and converts it to heat, which causes a disruption in the matrix of the image forming composition. Upon development with an aqueous alkaline developer, the exposed areas are removed while the nonexposed areas remain, thus forming a positive image.

Abstract: Electrochemically grained and anodized aluminum supports are treated with a post-treatment coating solution containing a polymer derived at least in part from vinyl phosphonic acid and phosphoric acid. This post-treated support is useful as substrates in the preparation of lithographic printing plate precursors. The post-treatment substrate treatment enables wide latitude in manufacturing and compatibility with silicate-free developers to achieve negligible background staining and oxide attack.

Abstract: A presensitized plate bringing about the lithographic printing plate which exhibits a high resistance to scumming and in which formation of bulges causing image dropouts is suppressed is provided with the lithographic printing plate support which includes an aluminum plate and an anodized film of aluminum provided on the aluminum plate, and has a micropore extending in the anodized film in the direction of depth from a film surface opposite with a film surface facing the aluminum plate. The micropore is sealed at least partially on its inside with protrusions made of boehmite, and the protrusions made of boehmite which are located on the anodized film have a mean height of less than 15 nm.

Abstract: Lithographic printing plate precursor comprising (a) a lithographic substrate with a hydrophilic surface and (b) a radiation-sensitive coating on the hydrophilic surface comprising (i) one or more types of monomers and/or oligomers and/or polymers, each comprising at least one ethylenically unsaturated group accessible to a free-radical polymerization, (ii) at least one sensitizer, and (iii) at least one coinitiator capable of forming free radicals together with the sensitizer, said coinitiator being other than metallocenes, characterized in that the at least one sensitizer comprises a compound of formula (I) wherein at least one of the groups R9 to R12 is a bulky group which has a van der Waals volume of at least 55 ?3.

Abstract: A lithographic printing plate precursor comprises an imageable layer comprising a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye that is defined by Structure (I) shown in the disclosure, which dyes comprise one or more ethylenically unsaturated polymerizable groups in an organic group that is attached to the methine chain. These infrared radiation absorbing dyes exhibit a reduced tendency to crystallize in the imageable layers in the presence of tetraaryl borate counter anions and therefore provide improved shelf life.

Abstract: A positive-working lithographic printing plate precursor for infrared laser is provided that includes, layered sequentially above a support, a lower layer and an upper layer, the lower layer and/or the upper layer including an infrared absorbing agent, either the lower layer comprising an alkali-soluble group-containing graft copolymer or the upper layer comprising a sulfonamide group-, active imide group-, and/or amide group-containing graft copolymer, and the graft copolymer being a polyurethane resin having as a graft chain an ethylenically unsaturated monomer-derived constitutional unit. There is also provided a process for making a lithographic printing plate, the process including in sequence an exposure step of imagewise exposing by means of an infrared laser the positive-working lithographic printing plate precursor for infrared laser and a development step of developing using an aqueous alkali solution with a pH of 8.5 to 10.8.

Abstract: A method for making a lithographic printing plate precursor is disclosed comprising the steps of a. providing a lithographic printing plate precursor including a support having a hydrophilic surface or which is provided with a hydrophilic layer, a photopolymerizable coating comprising a photopolymerizable composition, and an overcoat layer comprising a water soluble low molecular weight acid, wherein said overcoat layer has a surface pH-value ranging between 1 to 6; b. image-wise exposing the precursor; c. optionally heating the exposed precursor; d. processing the obtained precursor by applying a gum solution and optionally brushing the precursor, and/or by mounting the precursor on a plate cylinder of a lithographic printing press and rotating the plate cylinder while feeding dampening liquid and/or ink to the coating.

Abstract: A system and method are provided that incorporate a multi-layer plate configuration for a Digital Offset Plate (DOP) including at least a robust top imaging layer and a bottom layer that acts as a reservoir for the releasing oil in a proposed variable digital offset lithographic architecture. The top imaging layer may contain a small amount of oil (<20%) in a range suitable for allowing a small amount of oil to coat the surface and enable release of the ink. A bottom layer may be larger in volume and contain greater quantities (˜20-75%) of oil. Oil from the reservoir layer may diffuse to and through the top layer when the oil in the top surface layer is depleted in a manner that maintains a supply of oil at the surface. The top layer may act as a gate to maintain a steady flow of oil to the surface.

Abstract: A lithographic printing plate precursor includes, in the following order: a support; an image-recording layer which is capable of forming an image by removing an unexposed area with at least one of printing ink and dampening water on a printing machine after exposure and contains (A) an infrared absorbing dye, (B) a polymerization initiator, (C) a polymerizable compound and (D) a binder polymer having an alkylene oxide group; and a protective layer containing (E) a hydrophilic polymer containing at least a repeating unit represented by the formula (1) as defined herein and a repeating unit represented by the formula (2) as defined herein.