Abstract: A method of making a relief image printing element from a photosensitive printing blank is provided. A photosensitive printing blank with a laser ablatable layer disposed on at least one photocurable layer is ablated with a laser to create an in situ mask. The printing blank is then exposed to at least one source of actinic radiation through the in situ mask to selectively cross link and cure portions of the photocurable layer. Diffusion of air into the at least one photocurable layer is limited during the exposing step and preferably at least one of the type, power and incident angle of illumination of the at least one source of actinic radiation is altered during the exposure step. The resulting relief image comprises a plurality of dots and a dot shape of the plurality of dots is produced that is highly resistant to print fluting for printing on corrugated board.

Abstract: The invention provides a photosensitive element and a method for preparing a printing form from the element. The photosensitive element includes a layer of a photosensitive composition containing a binder, a monomer, and a Norrish type II photoinitiator, wherein the photosensitive layer has a transmittance to actinic radiation of less than 20% and contains reinforcing particles of graphene and/or carbon nanotubes.

Abstract: The invention provides a method for preparing a printing form from a photopolymerizable element. The photopolymerizable element includes a layer of a photopolymerizable composition containing an elastomeric block copolymer of polystyrene and polybutadiene having less than 15% by weight of 1,2-coupled bond segments in the polybutadiene block, an ethylenically unsaturated compound, and a photoinitiator. The method includes imagewise exposing the photopolymerizable element to actinic radiation in the presence of atmospheric oxygen; heating the element to a temperature sufficient to cause a portion of the layer to liquefy; and contacting an exterior surface of the photopolymerizable element with a development medium to allow at least a portion of the liquefied layer to be removed by the development medium.

Abstract: A method for making a positive-working lithographic printing plate includes the steps of: (1) providing a heat-sensitive printing plate precursor including on a support, having a hydrophilic surface or which is provided with a hydrophilic layer, a heat-sensitive coating; (2) image-wise exposing the precursor with heat and/or light; and (3) developing the exposed precursor with an aqueous alkaline developing solution including lithium ions at a concentration of at least 0.05% wt and a salt of an aliphatic carboxylic acid; wherein the molar ratio of the aliphatic carboxylic acid to the lithium ions is ?1.

Abstract: A resin composition for laser engraving that comprises (Component A) a resin that has a group selected from the group consisting of groups represented by Formula (I) to Formula (III) and is a plastomer at 20° C.; (Component B) an ethylenically unsaturated compound; and (Component C) a polymerization initiator. In Formula (I) to Formula (III), X, Y, and Z independently denote an alkylene group having 1 to 30 carbons, R1, R4, and R7 independently denote a hydrogen atom or a methyl group, R2, R3, R5, R6, R8, R9, R10, and R11 independently denote an alkyl group, an alkoxy group, a halogen atom, or a hydroxy group, and a wavy line portion denotes a position of bonding to another structure.

Abstract: Disclosed is a resin composition for laser engraving, comprising (Component A) a polyurethane resin that is a plastomer at 20° C. and has an ethylenically unsaturated group in a main chain and a side chain and (Component B) a polymerization initiator. Also disclosed is a flexographic printing plate precursor for laser engraving, comprising a relief-forming layer comprising the above-described resin composition.

Abstract: A method for treating a lithographic printing plate including the step of applying a liquid containing a surfactant to the plate, characterized in that the surfactant includes at least one hydrophilic segment including polyglycerol, and at least one hydrophobic segment selected from an optionally substituted alkylene group, an alkyl or aryl substituted poly(meth)acrylate, an optionally substituted polyester, polyether, polyurethane, polycarbosilane, polysiloxane, polystyrene and/or a polymer including a perfluoroalkyl group with the proviso that the liquid is not applied as a fountain solution.

Abstract: Negative-working imageable elements can be imaged and processed to provide lithographic printing plates. These imageable elements are sensitive to infrared radiation but are insensitive to “white” light and thus can be more easily handled under white light conditions. These properties are possible by incorporating a filter dye having a ?max of from about 300 to about 500 nm into the imageable layer of the imageable elements.

Abstract: A color contrast image in imaged lithographic printing precursors can be obtained by contacting the imaged precursor with a coloration solution containing a colorless form of a photochromic compound. Residual amounts of this compound attached to the oleophilic surface of the imaged precursor can be changed to its colored form when exposed to UV light. The coloration solution can be an alkaline or acidic developer or an alkaline or acidic solution used separately after development. The coloration solution can also be a gum solution.

Abstract: Disclosed is a method of making a lithographic printing plate which includes providing a lithographic printing plate precursor having a coating therein, image-wise exposing the coating, and developing the precursor. The coating includes (i) a contiguous photopolymerizable layer of a photopolymerizable composition or (ii) a contiguous intermediate layer with a photopolymerizable layer of a photopolymerizable composition thereon. The photopolymerizable composition includes a polymerizable compound, a polymerization initiator and a first polymer. The contiguous photopolymerizable layer or the contiguous intermediate layer also includes an adhesion promoting compound and a second polymer.

Abstract: An apparatus and method for improving the durability of an image on an imaging material, including increasing the press run length or a printing plate. The apparatus and method can involve the use of, as an example but not restricted to, an imaging device, a pre-bake oven, a processor, and a post-process treatment unit that employs infrared lamps adapted to irradiate the image.

Abstract: The invention relates to a method of producing a relief image arrangement, usable especially in the fields of flexography, embossing and heliogravure, and comprising a base layer and a layer of photosensitive material fixed on the base layer. The method is of the type according to which an image is produced on the photosensitive layer by causing selective curing by irradiating the zones that are to be in relief with light of a predetermined wavelength. The method is characterized in that the image is produced in the form of a set of points to which a substantially pyramidal shape is given, widening out in the direction of the base layer (5). The invention is usable for producing relief images, in the field of flexography.

Abstract: Particular embodiments include method embodiments and apparatus embodiments. One method embodiment comprises: placing a printing plate on an imaging device; imaging the plate according to imaging data; and applying UV radiation using a plurality of UV emitting LEDs during the process of imaging of the printing plate. In one embodiment, the plate initially has ablatable material, and wherein the imaging includes ablating ablatable material on the plate according to the imaging data to form an ablated plate, and wherein the applying the UV radiation includes exposing the ablated plate to UV radiation to cure the plate. In one embodiment, the imaging device is an external drum imager that includes a drum that rotates during imaging.

Abstract: A resin composition for laser engraving includes a binder polymer including a polyester, and an oxy compound of at least one of metal and metalloid selected from Groups 1 to 16 of periodic table.

Abstract: Printing members include very thin metal imaging bilayers that combine to trap and utilize imaging radiation and, due to their minimal thicknesses, ablate easily. The bilayer may include a first (bottommost) metal layer having a high extinction coefficient in the imaging wavelength range (e.g., 600-1200 nm) and, thereover, a second metal layer having a high transmittance and low emissivity for imaging radiation.

Abstract: A method for developing a printing plate precursor comprising the step of immersing the precursor in an aqueous alkaline developing solution comprising a (co)polymer comprising a monomeric unit which is represented by the following formula (I): wherein L is a linking group; R1, R2 and R3 independently represent hydrogen or an alkyl group; R4 represents an optionally substituted hydroxyaryl group; x=0 or 1; y=0 or 1 and when y=0 then x=1 and L is further bound to C* to form a cyclic structure.

Abstract: Lithographic printing plate precursors have been designed so that they can be stored, shipped, and used in stacks without interleaf paper between individual precursors. This is achieved by incorporating polymeric particles having an average diameter of from about 3 to about 20 ?m into the outermost precursor layer such as an imagable layer or topcoat. The polymeric particles comprise a core of a crosslinked polymer and have grafted hydrophilic polymeric surface groups that are grafted onto the particle surfaces by polymerizing hydrophilic monomers in the presence of the crosslinked polymeric particles. The lithographic printing plates can be either negative- or positive-working elements.

Abstract: A heat-sensitive negative-working lithographic printing plate precursor includes on a grained and anodized aluminum support a coating including hydrophobic thermoplastic polymer particles, a hydrophilic binder, and an organic compound, wherein the organic compound includes at least one phosphonic acid group or at least one phosphoric acid group or a salt thereof.

Abstract: A method of on-press development of a lithographic printing plate having an imaged photosensitive (PS) coating by (a) applying an emulsive film of press ink and fountain onto the entire PS coating; (b) transferring all nonimage areas of the inked PS coating and all of the ink film on the nonimage areas of the PS coating from the plate to a blanket roll while the image areas of the PS coating remain on the substrate, wherein the nonimage areas are transferred to the blanket roll in particulate form without dissolution or dispersion in any ink or fountain; and (c) contacting the blanket roll with a paper leader to further transfer all the ink, fountain water, and particles of nonimage PS coating that were transferred to the blanket roll, from the blanket roll to the paper leader.

Abstract: A method of preparing a lithographic printing plate in which no pre-heat step is used comprising the steps of:—providing a lithographic printing plate precursor comprising a support and a photopolymerizable image-recording layer, the image-recording layer comprising a monomer and a binder;—image-wise exposing the precursor in an exposure unit;—off press developing the exposed precursor with an aqueous solution in a processing unit; characterized in that the ratio of the total amount of monomer to the total amount of binder is at least 1 and the time lapse between exposing an image-area of the precursor and contacting the image-area with the aqueous solution is at least 1 minute.

Abstract: Negative-working imageable elements have a hydrophilic substrate and a single thermally-sensitive imageable layer. This layer can include an infrared radiation absorbing compound and polymeric particles that coalesce upon thermal imaging. These coalesceable polymeric particles comprise a thermoplastic polymer and a colorant to provide improved visible contrast between exposed and non-exposed regions in the imaged element, such as lithographic printing plates.

Abstract: Method for producing an imaged lithographic printing plate comprising the step of developing an imagewise exposed negative working precursor with a developer comprising an alkylene oxide derivative of formula (A), wherein R1 is a linear or branched C1 to C6 alkyl group or H, (n+m) is an integer from 2 to 30, and R2 R3 R4 and R5 are each independently selected from H, methyl and ethyl, with the proviso that at least one of R2 and R3 is not H, and with the further proviso that at least one of R4 and R5 is not H.

Abstract: A lithographic printing plate precursor includes: a support having a surface, a contact angle of water droplet in air on which is 70° or more; and a photosensitive layer, wherein the support has, on a surface of the support, a compound having a functional group X, the functional group X is a functional group capable of forming a chemical bond with a compound having a functional group Y which can interact with the functional group X, when the functional group X is brought into contact with the compound having a functional group Y, to adsorb the compound having a functional group Y on the surface of the support so as to decrease the contact angle of water droplet in air on the surface of the support to 30° or less.

Abstract: A plate making method of a lithographic printing plate comprising (1) preparing a lithographic printing plate precursor capable of forming an image with a semiconductor laser emitting an infrared ray having a wavelength from 760 to 1,200 nm which comprises a support and an image-recording layer containing a cyanine dye, a diphenyl iodonium salt or triphenyl sulfonium salt which may have a substituent on the phenyl group, a radical polymerizable compound and a polymer fine particle having a polyoxyalkylene chain in its side chain in this order, (2) placing a lith film on the lithographic printing plate precursor and reducing pressure so that the lith film is closely adhered to the lithographic printing plate precursor, (3) conducting UV exposure, and (4) conducting on-press development.

Abstract: Negative-working imageable elements such as lithographic printing plate precursors, include a free-radically polymerizable component, an initiator composition that is capable of generating free radicals sufficient to initiate polymerization of the free-radically polymerizable component upon exposure to imaging radiation in the presence of a radiation absorbing compound, a radiation absorbing compound, an aerobic free radical inhibitor, optionally a polymeric binder that is not a free radically polymerizable component, and an anaerobic free radical inhibitor. The molar ratio of the anaerobic free radical inhibitor to the aerobic free radical inhibitor is at least 1:1. This combination of inhibitors provides increased shelf life and good latent image stability particularly when the element includes a polymeric topcoat layer that functions as an oxygen barrier.

Abstract: A lithographic printing plate precursor comprising a support having a hydrophilic surface or which is provided with a hydrophilic layer, and a coating thereon, said coating comprising an IR absorbing agent and a polyvinylacetal binder, said polyvinylacetal comprising an acetal group having an acetal carbon atom substituted by a phenolic group, a naphtol group or an antracenol group, a second recurring unit comprising an acetal group having an acetal carbon atom substituted by an alkyl group having a hydrocarbon chain containing 1, 2 or 3 carbon atoms, and a third recurring unit comprising an acetal group having an acetal carbon atom substituted by an alkyl group having a hydrocarbon chain containing 1, 2 or 3 carbon atoms wherein the alkyl group of the acetal group of the third recurring unit is different from the alkyl group of the acetal group of the second recurring unit. The precursor exhibits an improved sensitivity on exposure and the stability against daylight exposure is further improved.

Abstract: A negative-working lithographic printing plate precursor have an outermost imageable layer that includes an oxygen scavenger and shelf-life stabilizer that is represented by either Structure (I) or Structure (II) below: HOOC—Ar—N(R1)(R2)??(I) HOOC—R5—N(R6)(R7)??(II) wherein Ar is a phenylene or naphthylene group, R1 and R2 are independently alkyl, alkenyl, alkynyl, phenyl, phenoxy, —R5OH, —CH2—C(?O)—R3, or —CH2—C(?O)O—R4 groups, R3 is hydrogen or an alkyl or phenyl group, R4 is an alkyl or phenyl group, R5 is an alkylene group, R6 and R7 are independently hydrogen or an alkyl, —R5OH, —R5C(?O)—R8, or —R5C(?O)OR9 group, R8 is hydrogen or an alkyl group, and R9 is an alkyl group, provided that the oxygen scavenger has no more than one carboxyl group.

Abstract: A multi-layer, positive-working lithographic printing plate precursor can be imaged with infrared radiation and processed in a single step using a single processing solution that has a pH greater than 6 and up to about 11. This single processing solution both develops the imaged precursor and provides a protective coating that need not be rinsed off before lithographic printing.

Abstract: Provided is a lithographic printing plate support that has excellent scratch resistance and is capable of obtaining a presensitized plate which exhibits excellent on-press developability and enables a lithographic printing plate formed therefrom to have a long press life and excellent deinking ability after suspended printing. The lithographic printing plate support includes an aluminum plate, and an aluminum anodized film formed thereon and having micropores which extend in a depth direction of the anodized film from a surface of the anodized film opposite from the aluminum plate. Each micropore has a large-diameter portion which extends to a depth of 5 to 60 nm (depth A) from the anodized film surface, and a small-diameter portion which communicates with the bottom of the large-diameter portion, further extends to a depth of 900 to 2,000 nm from the communication position and has a predetermined average diameter.

Abstract: A method includes removing the previously imaged area (120) from the flexographic plate (104) to create an opening in the flexographic plate; providing a portion (108) from a flexographic plate built from similar material of the previously imaged flexographic plate; adding adhesive material (116) to the portion or to the opening or to the portion and to the opening; placing the opening within the portion; curing the adhesive material to permanently fix the portion to the flexographic plate; polishing the top (508) of the portion to match to the top surface (504) of the flexographic plate; and imaging the portion.

Abstract: A heat-sensitive lithographic printing plate precursor comprising on a grained and anodized aluminum support a compound which is capable of converting form a hydrophobic state to a hydrophilic state or vice versa upon exposure to heat, and is represented by the following formula: A-(L)n-B wherein L represents a linking group, n represents 0 or 1 and B represents a thermo-labile group; characterized in that the compound further comprises the group A which is a functional group capable of interacting with the surface of a grained and anodized aluminum support and is selected from the list consisting of a halosilanyl group, an alkoxysilanyl group, a phosphonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a salicylic acid group or a salt thereof, a boronic acid group or an ester or a salt thereof, an optionally substituted di or tri-hydroxyaryl group, an optionally substituted salicaldoxime group, an optionally substituted salicaldimine group, an optionally substituted hydroxyheteroa

Abstract: There are provided an ink composition including a polymerization initiator, a polymerizable monomer and a phosphoric acid group-containing polymer having a weight-average molecular weight in a range of 10,000 to 30,000; an inkjet recording method using the ink composition; a printed material recorded by the inkjet recording method; a method of producing a planographic printing plate using the ink composition; and a planographic printing plate obtained by the method of producing a planographic printing plate.

Abstract: Negative-working imageable elements can be imaged and processed to provide lithographic printing plates, especially with sulfuric acid-anodized aluminum substrates. These elements have an imageable outermost layer that contains two different polymeric binders, a primary polymeric binder is optionally present a discrete particles, and a secondary polymeric binder comprising a poly(vinyl acetate) that has a degree of hydrolysis of less than 60 mol %. These imageable elements can be designed for either off-press or on-press development.

Abstract: A heat-sensitive positive-working lithographic printing plate precursor comprising (1) a support having a hydrophilic surface or which is provided with a hydrophilic layer, (2) a heat-sensitive coating, comprising an underlayer on said support and thereon an upperlayer, an IR absorbing agent in at least one of said underlayer and upperlayer, a phenolic resin in said upperlayer, and a first polymer in said underlayer, characterized in that said first polymer is an alkaline soluble polymer comprising a first sulfonamide containing monomeric unit having a specified structure according to formula I or formula II and a second amide containing monomeric unit having a specified structure according to formula III. The printing plates show an improved chemical resistance of the coating and a reduced undercutting of the image forming parts of the coating.

Abstract: A heat-sensitive negative-working lithographic printing plate precursor comprising: a support having a hydrophilic surface or which is provided with a hydrophilic layer; and an image-recording layer comprising hydrophobic thermoplastic polymer particles and an infrared light absorbing dye; characterized in that: said image-recording layer further comprises a compound, said compound comprising an aromatic moiety and at least one acidic group or salt thereof and having a most bathochromic light absorption peak at a wavelength between 300 nm and 450 nm.

Abstract: A plate making method of a lithographic printing plate precursor includes: exposing imagewise a lithographic printing plate precursor including a support and an image-forming layer and containing (A) a compound generating an acid with light or heat, (B) an aromatic hydrocarbon compound or heterocyclic compound substituted with a functional group containing a nitrogen atom and (C) an aromatic aldehyde protected with an acid-decomposable group; and removing an unexposed area of the image-forming layer of the lithographic printing plate precursor by supplying at least one of dampening water and ink on a cylinder of a printing machine.

Abstract: Positive-working imageable elements having improved sensitivity, high resolution, and solvent resistance are prepared using a water-insoluble polymeric binder comprising vinyl acetal recurring units that have pendant hydroxyaryl groups, and recurring units comprising carboxylic acid aryl ester groups that are substituted with a cyclic imide group. These imageable elements can be imaged and developed to provide various types of elements including lithographic printing plates.

Abstract: Provided is a directly imageable waterless planographic printing plate precursor that comprises at least a heat sensitive layer and a silicone rubber layer formed on a substrate in this order and has a high sensitivity not only immediately after the precursor production but also after the passage of time. In the directly imageable waterless planographic printing plate precursor, the heat sensitive layer contains liquid bubbles filled with a liquid with a boiling point in the range of 210 to 270° C. Also provided is a production method for making a directly imageable waterless planographic printing plate precursor.

Abstract: An imageable element can be imaged using non-ablative processes. This element has a non-silicone, non-crosslinked layer contiguous to and under an ink-repelling crosslinked silicone rubber layer. These elements can be used for providing lithographic printing plates useful for waterless printing (no fountain solution). Processing after imaging is relatively simple with either water or an aqueous solution consisting essentially of a surfactant or mechanical means to remove the crosslinked silicone rubber layer and a minor portion of the non-silicone, non-crosslinked layer in the imaged regions.

Abstract: Single- and multi-layer positive-working imageable elements include an ink receptive outer layer that includes inorganic, non-metallic, inert discrete particles, such as nano-sized silica, aluminum oxide, or titanium dioxide particles. The presence of these particles in the outermost layer improves the abrasion and scratch resistance of the elements.

Abstract: A process for treating an imaged printing form, in particular a printing form covered with amphiphilic molecules or with polymers, such as saccharides, includes applying a gum, in particular a microscopic gum layer, to the surface of the printing form in the liquid state. The gum is removed or reduced down to a remaining nanoscopic covering after a short or negligible time interval, relative to the time interval until the application of lithographic liquid, for example dampening solution or printing ink, to the surface. The removal or reduction of the gum is preferably carried out in the still liquid state, i.e. before the applied gum dries on, and preferably immediately after the application. The remaining gum covering protects the printing form against contaminants and increases its hydrophily/hydrophoby contrast. An apparatus for treating an imaged printing form, a re-imageable printing form and a machine for processing printing material, are also provided.

Abstract: A method of making a flexographic printing form precursor for laser engraving including the steps of (i) providing at least one layer of a curable composition on a substrate; (ii) curing the at least one layer; wherein the curable composition defining an outermost layer includes at least 0.5% by weight relative to the total weight of the composition of an organo-silicon compound including at least one polymerizable group; and a urethane (meth)acrylate oligomer having three or less polymerizable groups.

Abstract: An aluminum alloy plate for a lithographic printing plate capable of obtaining a lithographic printing plate having an excellent resistance to spotting, a method of manufacturing such aluminum alloy plate, a lithographic printing plate support obtained by using such aluminum alloy plate, and a presensitized plate and in particular an on-machine developable presensitized plate are provided. The aluminum alloy plate contains 0.08 to 0.45 wt % of iron and 0.05 to 0.20 wt % of silicon, with the balance being inadvertent impurities and aluminum, and the content of aluminum-iron intermetallic compounds is not more than 0.05 wt %.

Abstract: A thermal positive-type planographic original printing plate comprising a support and at least one recording layer provided on the support, either the same layer or different layers of the recording layer comprising: a star polymer in which at least 3 polymer chains bind to a core comprised atomic groups and are radially branching; and an infrared absorbing agent.

Abstract: The invention pertains to a method for preparing a composite printing form from a single precursor that is capable of forming a relief and a carrier. The single precursor can be a single photosensitive element or a single laser-engravable print element having a reinforced elastomeric layer. The single precursor has a size that is at least 70% of a size of the carrier. The single precursor is located on the carrier by approximately positioning the precursor on the carrier that has no registration markings. Precise registration of the single precursor is achieved by using digital information generated from a computer to create the registered image on the composite form. The method is particularly suited for preparing composite printing forms for relief printing, and in particular for preparing composite printing forms for flexographic printing of corrugated substrates.

Abstract: A method for preparing lithographic printing plates for on-press development, including sequentially feeding the plates to an imaging station to produce a plurality of latent image reference marks allocated among at least two margins along a respective two sides of the plate, and a latent print image within the margins. The imaged plates are transported from the imaging station to a plate bending station where the short ends of the plate are bent over. Between the imaging station and the bending station, the unimaged areas of the coating in at least two of the margins are removed to reveal the reference marks without developing the latent print image. Preferably, the reference marks are revealed while the plate is temporarily aligned in landscape orientation at stop, such as at the feeder to the bending station.

Abstract: Negative-working imageable elements have an imageable layer comprising a free radically polymerizable component, an initiator composition capable of generating radicals sufficient to initiate polymerization of the free radically polymerizable component upon exposure to imaging radiation, a radiation absorbing compound, one or more polymeric binders, and at least 5 weight % of core-shell particles comprising a hydrophobic polymeric core and a hydrophilic polymeric shell that is covalently bound to the polymeric core. The hydrophilic polymeric shell has one or more zwitterionic functional groups. These elements can be imaged such as by IR lasers to provide lithographic printing plates.

Abstract: The invention is directed to a lithographic printing plate precursor including, in the following order: a support; an image-recording layer containing a radical polymerizable compound and a radical polymerization initiator; and a protective layer containing a star polymer, and the star polymer is preferably a polymer in which from 3 to 10 polymer chains are branched from a central skeleton.

Abstract: A method of on-press developing a high-speed laser sensitive lithographic printing plate with ink and/or fountain solution is described. The plate comprises on a substrate a photosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to a laser. The plate is exposed with a laser and on-press developed with ink and/or fountain solution. At least a portion of the on-press development is performed with the plate under a yellow-red light, in substantial darkness, or under a light that is different from the light for printing and does not cause hardening of the photosensitive layer during on-press development.

Abstract: Lithographic printing plates can be prepared with enhanced contrast between the image and background by coloring the imaged or exposed regions using a coloring fluid containing a water-insoluble colorant (dye or pigment) and an organic solvent that swells the imaged regions sufficiently for the colorant to be embedded or diffused therein.