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 presensitized plate having: on an aluminum support, a thermosensitive layer containing a photothermal conversion agent which absorbs infrared rays and generates heat and a water-insoluble and alkali-soluble resin, of which solubility to an alkali aqueous solution increases by heating, wherein the aluminum support has a grained structure with large undulation and a grained structure with small undulation on a surface thereof. This presensitized plate is excellent in damage resistance and sensitivity, and after the plate is processed into a lithographic plate, it is also excellent in scum resistance and press life.

Abstract: Infra-red absorbing polymers useful in imageable products and the lithographic printing field comprise infra-red absorbing groups carried as pendent groups on a polymer backbone. Certain infra-red absorbing groups may also act to insolublize the polymer in a developer, until it is imagewise exposed to infra-red radiation. The resulting heat renders the polymer soluble in the developer. Imageable products employing the infra-red absorbing polymers may include positive working lithographic printing plates.

Abstract: A photothermographic material that comprises a support having thereon one or more thermally-developable imaging layers comprising a binder and in reactive association, a photosensitive silver halide, a non-photosensitive source of reducible silver ions, and a reducing composition for the non-photosensitive source reducible silver ions. The thermally-developable layers further comprises one or more radiation absorbing compounds that provide a total absorbance of greater than 0.6 and up to and including 3 in the thermally-developable imaging layer(s). These photothermographic materials exhibit reduced mottle without significant loss in sensitivity.

Abstract: A direct-to-press imaging method comprises: (a) applying an imageable coating to a printing cylinder, wherein the imageable coating comprises a composition such as a thermally switchable polymer which changes affinity for a printing fluid upon exposure to imaging radiation such as infrared radiation delivered imagewise via a laser, and the imageable coating is substantially insoluble in the printing fluid; (b) imagewise exposing the imageable coating to actinic radiation to obtain an imaged coating; (c) printing a plurality of copies of an image from the imaged coating; and (d) reapplying the imageable coating as desired by repeating steps (a) through (c) at least once without substantially removing the prior imaged coating before reapplying the imageable coating.

Abstract: A method for imaging patterning compositions comprising the steps of:

Abstract: A positive planographic printing plate precursor includes a support having disposed thereon a lower thermosensitive layer containing a water-insoluble but alkali-soluble polymer compound and an upper thermosensitive layer containing a water-insoluble but alkali-soluble polymer compound, with alkali-solubility increasing under heat, wherein (i) both the upper thermosensitive layer and the lower thermosensitive layer contain an IR absorbing dye, with the ratio of the IR absorbing dye concentration in the upper thermosensitive layer to the IR absorbing dye concentration in the lower thermosensitive layer is 1.6 to 10.0, and/or (ii) the upper thermosensitive layer and the lower thermosensitive layer contain different IR absorbing dyes, and/or (iii) at least one of the upper thermosensitive layer and the lower thermosensitive layer contains an IR absorbent having, in one molecule, at least two chromophoric groups that absorb IR light, with the chromophoric groups bonding to each other via a covalent bond.

Abstract: The present invention relates to IR-sensitive compositions suitable for the manufacture of printing plates developable on-press. The IR-sensitive compositions comprise a first polymeric binder which does not comprise acidic groups having a pKa value≦8; a second polymeric binder comprising polyether groups; an initiator system; and a free radical polymerizable system comprising at least one member selected from unsaturated free radical polymerizable monomers, free radical polymerizable oligomers and polymers containing C═C bonds in the back bone and/or in the side chain groups. The initiator system includes (i) at least one compound capable of absorbing IR radiation; (ii) at least one compound capable of producing radicals selected from polyhaloalkyl-substituted compounds; and (iii) at least one polycarboxylic acid of formula R4—(CR5R6)r—Y—CH2COOH, wherein oxi<redii+1.

Abstract: An image recording medium comprising a light and heat change material capable of recording an image with laser beam is described, characterized in that therein are incorporated a heat generator having no absorption at a wavelength of 500 nm or more which undergoes exothermic decomposition to amplify heat generation when acted upon by heat and a compound which undergoes thermochemical reaction to show an absorption change at a wavelength of from 360 nm to 900 nm.

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: Photochemical acid progenitors in combination with dihydroperimidine squarylium dyes have been found to be particularly effective at generating acid upon irradiation with near-infrared radiation. It has been found that dihydroperimidine squarylium dyes that are particularly useful in this invention have an oxidation potential greater than about 0.5 V relative to SCE as measured in dichloromethane.

Abstract: In accordance with the present invention there is provided an imaging element for lithographic offset printing. The imaging element comprises hydrophobic polymer particles in an aqueous medium, a substance for converting light into heat and an inorganic salt. The imaging element may be used for printing long run lengths on lower quality paper and in the presence of set-off powder. The imaging element may be imaged and developed on-press and may be sprayed onto a hydrophilic surface to create a printing surface that may be processed wholly on-press. The hydrophilic surface may be a printing plate substrate or the printing cylinder of a printing press or a seamless sleeve around the printing cylinder of a printing press. This cylinder may be conventional or seamless.

Abstract: Disclosed is a printing plate precursor comprising a substrate and provided thereon, a layer containing a light heat conversion material, wherein the light heat conversion material does not substantially change in nature when allowed to stand in a temperature atmosphere of 400 to 500° C. for 10 minutes or a printing plate precursor comprising a substrate and provided thereon, a hydrophilic layer which is porous, wherein the hydrophilic layer contains a carbon atom-free material in an amount of not less than 91% by weight.

Abstract: An image-forming material which has high sensitivity and is excellent in image-forming performance and which does not produce smudges on an optical system of an exposing apparatus, and a planographic printing original plate which uses this image-forming material and can produce images by an infrared laser for a direct plate-making process. These can be achieved by an image-forming material containing an infrared absorber having in the same molecule thereof two or more chromophoric groups which can absorb infrared radiation and are each bonded by a covalent bond.

Abstract: A heat-developable photosensitive material comprises: a support; a light-sensitive silver halide; a reducing agent for a silver ion; a binder; and a light-insensitive organic silver salt grain, wherein the light-insensitive organic silver salt grain contains a silver behenate in an specific amount.

Abstract: Method of on-press developing a thermosensitive lithographic printing member with ink and/or fountain solution is described. The printing member comprises on a substrate a thermosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to an infrared radiation. The printing member can be a pre-coated plate or can be prepared on press by coating a thermosensitive layer onto a substrate that is a sheet material or a seamless sleeve mounted on a plate cylinder or is the surface of a plate cylinder of the lithographic press.

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.

Abstract: The present invention provides a spectrally sensitized photothermographic silver halide element comprising a support layer having on at least one surface thereof a photothermographic composition which displays uniform image density across its surface when exposed to floodlight or uniform incandescent light exposure at radiation wavelengths to which the element is sensitive, said element comprising at least two layers, including a top layer and a photothermographic emulsion layer, said photothermographic emulsion layer comprising a binder, a light insensitive silver source, a reducing agent for silver ion and infrared radiation sensitive silver halide grains, wherein the coherent radiation is rendered more diffuse in its passage through the element than when it strikes the top layer. This may be accomplished at least in part by 1) the top layer of the element having haze induced therein of 0.

Abstract: Thermally developable photothermographic materials comprise a backside layer that includes a toner as a backside stabilizer. Useful backside stabilizers include pyridazine, phthalazine, phthalazinone, benzoxazine dione, benzthiazine dione, or quinazoline dione compounds, or derivatives of any of these compounds to provide improved shelf stability. These backside stabilizers can be provided particularly in non-photosensitive compositions that include an antihalation composition.

Abstract: The present invention is directed to a photothermographic element comprising at least one imaging layer with a pyrrolotriazole coupler and a developing agent, or precursor thereof, the combination of which is capable of forming an image record in the infrared region of the light spectrum in response to a selected hue of visible light. This expedient leads to the formation of high quality images, especially when scanning photothermographic elements in which the silver halide, metallic silver, and/or any organic silver salts have not been removed. Also disclosed is a method for photothermographically forming a developed image comprising an infrared image record.

Abstract: A process for making thermally imageable negative working compositions comprising the steps of: (1) providing a patterning composition layer on a substrate, said patterning composition comprising: (a) at least one thermal-generator acid generator, (b) at least one cross-linking resin or compound; (c) at least one binder resin comprising a polymer containing at least one reactive pendent group selected from the group, consisting of hydroxyl, carboxylic acid, sulfonamide, alkoxymethylamide and mixtures thereof; and (d) at least one infrared absorber; (2) subjecting the patterning composition layer to a two-stage radiation exposure; (a) one stage being a flood UV-exposure; and (b) the other stage being a imagewise infrared exposure stage; (3) treating the exposed patterning composition with heat energy; and (4) developing the heat treated, exposed patterning composition with an aqueous alkaline developer to remove the non-imaged areas of the patterning composition and leaving the imaged areas substanti

Abstract: A photosensitive flexographic printing element for the production of flexographic printing plates by digital imaging by means of lasers which has an IR-ablative layer with a polyether-polyurethane as binder. A process for the production of flexographic printing plates using an element of this type.

Abstract: The present invention can provide a heat-sensitive lithographic printing plate which can be subjected to aqueous development or does not require any special treatment such as wet development and rubbing after image writing, in particular, a heat-sensitive lithographic printing plate which can be subjected to recording by a solid laser or semiconductor laser emitting infrared rays to allow direct plate making from digital data. Furthermore, the present invention can provide a heat-sensitive lithographic printing plate excellent in press life. The heat-sensitive lithographic printing plate comprises an image-forming layer containing a polymer which is capable of changing its hydrophilicity by heat and is crosslinked by crosslinking reaction.

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.

Abstract: A photothermographic material comprises: a support; a binder; an organic silver salt; a reducing agent for silver ion; and a photosensitive silver halide grain, wherein said photothermographic material contains a solvent in an amount of from 5 to 1,000 mg/m2 and the intensity of an odor generated from said photothermographic material is from −3 to 1 at 120° C.

Abstract: A printing plate element is disclosed, comprising a substrate and a component layer containing a first material which is water-insoluble or capable of varying from being water-soluble to being water-insoluble at a prescribed temperature of not less than 60° C. and a second material which is water-soluble and has a melting point of 60 to 300° C. A method of preparing a printing plate is also disclosed, comprising imagewise exposure of the printing plate element and removing an unexposed area of the printing plate element with aqueous solution.

Abstract: A lithographic printing method is disclosed which comprising the steps of providing an imaging material which comprises a support and an image-recording layer that is not removable with a single-fluid ink which comprises an ink phase and a polar phase; image-wise exposure of the image-recording layer to heat or light without substantially ablating said image-recording layer, thereby switching the affinity of the image-recording towards ink or an ink-abhesive fluid and thereby creating a printing master comprising a lithographic image which consists of unexposed areas that have affinity for one phase of said ink phase and polar phase and of exposed areas that have affinity for the other phase of said ink phase and polar phase; printing, wherein the single-fluid ink is supplied to the printing master.

Abstract: A copolymer useful in radiation sensitive compositions for lithographic printing plates comprises the units A, B, C and D, wherein A is present in an amount of 0.5 to 30 wt.-% and is of the formula wherein R is hydrogen, C1-C4 alkyl, —CH═COOH or B is present in an amount of 5 to 35 wt.-% and is of the formula C is present in an amount of 10 to 55 wt.

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

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

Abstract: A positive working printing form precursor comprises a thermally imagable composition which includes a hydroxyl group-containing polymer, for example a novolak resin. The composition has a weight of less than 1.1 gm−2. It has been found that using a low weight of the composition on the precursor improves the properties of the precursor, in particular by rendering the sensitivity of the precursor to imaging radiation less variable over time.

Abstract: A photosensitive printing element is used for preparing flexographic printing plates. The photosensitive printing element comprises (a) a support and especially a flexible support, (b) a photopolymerizable layer comprising an elastomeric composition sensitive to non-infrared actinic radiation, said layer being soluble, swellable or dispersible in a liquid developer prior to exposure to said non-infrared actinic radiation, and (c) at least one layer comprising a radiation-sensitive imaging layer, such as an infrared radiation sensitive thermographic material that provides excellent image density (e.g., greater than 3.0) at least in the electromagnetic region of said non-infrared radiation sensitivity and preferably in both the visible and ultraviolet regions of the electromagnetic spectrum upon exposure to infrared laser radiation and thermal development. Imaging of the imaging layer (e.g.

Abstract: The present invention provides an imageable composition, which includes a bottom layer including a first strong, non-volatile acid having a pKa of not more than about 8 and coated thereon a top layer including an acid curable composition, an acid generator, an infrared absorber and optionally a colorant. The present invention further provides an imageable element, which includes a substrate and an imageable composition according to the present invention coated on a surface of the substrate. Also provided is method of producing an imaged element according to the present invention.

Abstract: A positive working lithographic printing plate precursor comprising a lower layer containing a water-insoluble and alkali-soluble resin, and an upper heat-sensitive layer containing a water-insoluble and alkali-soluble resin and an infrared absorbing dye and increasing the solubility in an alkaline aqueous solution by heating, provided in this order on a hydrophilic support, and (a) the upper heat-sensitive layer containing at least two kinds of surface active agents, or (b) the lower layer and upper heat-sensitive layer each containing a surface active agent different from each other.

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

Abstract: In accordance with the present invention there is provided an imaging element for lithographic offset printing. The imaging element comprises hydrophobic polymer particles in an aqueous medium, a substance for converting light into heat and an inorganic salt. The imaging element may be used for printing long run lengths on lower quality paper and in the presence of set-off powder. The imaging element may be imaged and developed on-press and may be sprayed onto a hydrophilic surface to create a printing surface that may be processed wholly on-press. The hydrophilic surface may be a printing plate substrate or the printing cylinder of a printing press or a seamless sleeve around the printing cylinder of a printing press. This cylinder may be conventional or seamless.

Abstract: The present invention provides an image recording material onto which images can be recorded with an infrared ray, the material comprising an infrared absorbent (A), a radical-generating agent (B) and a radically polymerizable compound (C), wherein the infrared absorbent is a cyanine dye in which at least one substituent on a nitrogen atom in a heterocyclic ring at each end forms a cyclic ring which includes a methine chain.

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

Abstract: The present invention provides an IR-sensitive composition, which includes: a polymeric binder; and a free radical polymerizable system consisting of: at least one component selected from unsaturated free radical polymerizable monomers, oligomers which are free radical polymerizable and polymers containing C═C bonds in the backbone and/or in the side chain groups; and an initiator system, which includes: (a) at least one compound capable of absorbing IR radiation; (b) at least one compound capable of producing radicals; and (c) at least one carboxylic co-initiator, provided that the total acid number of the polymeric binder is 70 mg KOH/g or less. The present invention further provides a printing plate precursor, a process for preparing the printing plate and a method of producing an image.

Abstract: A negative-working image forming process which comprises the steps of:

Abstract: A lithographic printing plate for infrared laser is provided which shows an excellent coated surface state and an excellent stability with time against scratch, and which has a heat-sensitive layer containing the following (A) to (D):

Abstract: A black-and-white photothermographic material that is sensitive at a wavelength greater than 700 nm, and comprises a support having thereon one or more thermally-developable imaging layers comprising a binder and in reactive association, a photosensitive silver halide, a non-photosensitive source of reducible silver ions, and a reducing composition for the non-photosensitive source reducible silver ions. The thermally-developable layers further comprises one or more indolenine dyes as post-processing stabilizing compounds and one or more merocyanine dyes or cyanine spectral sensitizing dyes that comprise one or more thioalkyl, thioaryl, or thioether groups.

Abstract: The present invention includes an imageable element, comprising a substrate and a thermally imageable composition which includes a graft copolymer having hydrophobic and hydrophilic segments. Upon imagewise exposure to thermal energy, the graft copolymer produces exposed regions that are less soluble in a developer than the unexposed regions. Also included is a method of producing an imaged element which includes a graft copolymer according to the present invention.

Abstract: A lithographic printing plate precursor comprises a support and a hydrophilic layer capable of hydrophobicizing by heat,

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: The present invention provides an imageable composition, which includes an acid curable composition, an acid generator, an infrared absorber, optionally a colorant, such as, a colorant dye or colorant pigment, wherein at least one of the infrared absorber and the colorant has a counter anion derived from a non-volatile acid, and further optionally, a strong acid. The present invention further provides an imageable element, which includes a substrate and an imageable composition according to the present invention coated on a surface of the substrate. Also provided is method of producing an imaged element according to the present invention.

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

Abstract: A blank printed circuit board (10), for creating a circuit pattern thereon by direct imaging with infrared radiation. The blank printed circuit board (10) includes in sequence an insulating substrate (20), a metal layer (21), a resist layer (22) and a mask layer (23).

Abstract: A lithographic printing plate precursor comprising a hydrophilic support, an alkali-soluble layer and provided on the alkali-soluble layer a recording layer which contains an infrared ray absorbent, an alkali-soluble resin and an inhibitor of inhibiting the alkali-soluble resin from dissolving in an alkali aqueous developer and increases in the solubility in an alkaline aqueous solution upon irradiation of infrared light, and a developing method of the lithographic printing plate precursor with a non-silicate developer.

Abstract: Photochemical acid progenitors in combination with dihydroperimidine squarylium dyes have been found to be particularly effective at generating acid upon irradiation with new-infrared radiation. It has been found that dihydroperimidine squarylium dyes that are particularly useful in this invention have an oxidation potential greater than about 0.5 V relative to SCE as measured in dichloromethane.