Abstract: A lithographic printing plate precursor comprises: a support; and an image-forming layer including a copolymer containing a specific fluoroaliphatic group and a repeating unit corresponding to at least one of a poly(oxyalkylene) acrylate and a poly(oxyalkylene) methacrylate.

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: Positive-working thermally imageable elements, useful as printing plate precursors and having reduced ablation when thermally imaged, and methods for their preparation are disclosed. In one aspect, the elements contain a hydrophilic substrate, an underlayer, a barrier layer, and a top layer. The underlayer comprises a photothermal conversion material.

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.

Abstract: Objects of the present invention are to provide a positive working presensitized plate of a thermal type, which has damage resistance, and which is handled easily in conventional operation, high in sensitivity and excellent in press life when used as a lithographic printing plate, and to provide a support for a lithographic printing plate, which is suitably used for the same. The objects have been achieved by a support for a lithographic printing plate obtained by performing graining treatment, alkali etching treatment and anodizing treatment on an aluminum plate, wherein a ratio of a real area of a surface thereof to an apparent area of the surface set larger by 1.3 to 1.8 times, comprising a pit having an average diameter of 0.3 to 1.

Abstract: A presensitized plate which comprises an aluminum support having a grain shape in a structure in which grained structures having specified average wavelength (average aperture diameters) are superimposed, a hydrophilic layer whose thermal conductivity falls within a predetermined range and which is formed on the aluminum support, and an image recording layer of thermal positive type formed on the hydrophilic layer, exhibits a high sensitivity, has a long press life when processed into a lithographic printing plate, and is resistant to scum in the non-image area.

Abstract: A presensitized plate in which an image recording layer is formed on a support for a lithographic printing plate obtainable by performing a treatment with an aqueous solution containing one or more divalent or multivalent cations at a concentration ranging from 0.0001 mol/L to less than 0.020 mol/L is excellent in both scum resistance and press life when processed into a lithographic printing plate.

Abstract: A photosensitive lithographic printing plate comprises a photosensitive layer and a protective layer formed in this order on a support, wherein the photosensitive layer has a maximum peak of spectral sensitivity within a wavelength range ranging from 390 to 430 nm, the minimum exposure for the photosensitive lithographic printing plate for image formation at a wavelength of 410 nm (S410) is at most 100 &mgr;J/cm2, and the relation between the minimum exposure for image formation at a wavelength of 450 nm (S450) and the minimum exposure for image formation at a wavelength of 410 nm (S410) is 0<S410/S450<0.1.

Abstract: A lithographic printing plate precursor is disclosed, which comprises an image-forming layer which contains a hydrophilic resin, an acid precursor and at least one component selected from fine particles containing a compound having a vinyloxy group and microcapsules containing a compound having a vinyloxy group, on a hydrophilic support, which can be development processed on a printing machine.

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: The invention relates to a recording material for the production of offset printing plates having a web- or plate-form support, a radiation-sensitive layer on the front of the support and a continuous layer on its back. The back layer has a glass transition temperature Tg of at least 55° C. and a surface resistance of 106&OHgr; or less.

Abstract: A support for a lithographic printing plate with no damage in appearance such as unevenness in the form of streaks and with excellent pit homogeneity. A support for a lithographic printing plate obtained by subjecting a surface of an aluminum alloy plate to a surface treatment including alkali etching and an electrochemical graining treatment, wherein the aluminum alloy plate shows dispersion of 50% or lower for each element, the dispersion being defined by an specific equation with regard to contents of Fe, Si, Mn, Mg and Sn in a surface layer portion thereof which is from the surface to a depth of 1 &mgr;m.

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 coalescence inhibitor. 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 method of making improved aluminum printing plates comprising graining the aluminum plates, de-smutting them by treating them with nitric acid solution, then rinsing with hot water, acetating the aluminum plates, and silicating the aluminum plates. The plates are then coated with a photoresist, pattern exposed and developed. The printing plates of the invention have improved characteristics; they have excellent adhesion of the resist in image areas, and ink repellency in non-image areas. The developed printing plates have excellent durability without baking.

Abstract: A method of processing imageable elements useful as alkaline-developable lithographic printing plate precursors that does not require either a rinsing step or a further gumming step is disclosed. The method comprises simultaneously developing and gumming the imaged element with an aqueous alkaline developing-gumming solution comprising one or more water-soluble polyhydroxy compounds of the following structure: R1(CHOH)nR2 in which n is 4 to 7; and either (i) R1 is hydrogen, aryl, or CH2OH; and R2 is hydrogen, alkyl group having 1 to 4 carbon atoms, CH2OR3 in which R3 is hydrogen or an alkyl group having 1 to 4 carbon atoms, CH2N(R4R5) in which R4 and R5 are each independently hydrogen or an alkyl group having 1 to 4 carbon atoms, or CO2H, or (ii) R1 and R2 together form a carbon—carbon single bond.

Abstract: The present invention provides a PS plate for use in making a lithographic printing plate, comprising an aluminum substrate provided thereon with a light-sensitive layer comprising a polyurethane resin binder, an addition polymerizable ethylenically unsaturated bond-containing compound and a photopolymerization initiator, wherein the polyurethane resin binder is one synthesized from at least the following compounds (i) to (iv): (i) at least one di-isocyanate compound; (ii) at least one diol compound having at least one carboxyl group; (iii) at least one diol compound whose logP value is less than 0; and (iv) at least one diol compound whose logP value is higher than 0.

Abstract: A thinner for rinsing photoresist including 50 to 80 wt. % of n-butyl acetate, propylene glycol alkyl ether, and propylene glycol alkyl ether acetate, is provided. The thinner is neither toxic to humans nor ecologically undesirable and has no unpleasant odor. The waste solutions thereof and associated waste water are easily handed so as to render this thinner environmental friendly. Additionally, the photoresist thinner of the present invention has excellent rinsing ability.

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 for preparing a lithographic printing plate involving the steps of subjecting, to imagewise exposure, a presensitized plate for use in making a lithographic printing plate comprising an aluminum substrate provided thereon with a light-sensitive layer formed from a photopolymerizable light-sensitive composition, which comprises a compound having an ethylenically unsaturated double bond, a photopolymerization initiator and a polyurethane resin binder and then developing the imagewise exposed plate with a developer containing an inorganic alkaline agent and a nonionic surfactant, carrying a polyoxyalkylene ether group, having a pH value ranging from 10.0 to 12.5 and an electrical conductivity ranging from 3 to 30 mS/cm.

Abstract: A planographic printing plate precursor comprising: an aluminum substrate which has been subjected to a roughening treatment and an anodizing treatment; and a photosensitive layer which provided on a surface of said substrate, and which contains an infrared absorbing agent and a water-insoluble and alkali aqueous solution-soluble polymer compound, and whose solubility in an alkali developing solution varies by infrared laser exposure, wherein said substrate is obtained by electrochemically roughening an aluminum alloy plate which contains a trace amount of certain elements to an aluminum alloy of high purity.

Abstract: A presensitized plate useful for making a lithographic printing plates comprises an aluminum substrate provided thereon with a photopolymerizable light-sensitive layer, wherein the light-sensitive layer comprises an ethylenically unsaturated bond-containing compound having at least three methacryloyl or acryloyl groups alone or in any combination in the molecule and the substrate is Substrate A, which has, on the surface, grained structures comprising medium waved structure whose average pore size ranges from 0.5. to 5 &mgr;m and small waved structure whose average pore size ranges from 0.01 to 0.2 &mgr;m, which are superimposed; or Substrate B, which has, on the surface, grained structures comprising large waved structure whose average wavelength ranges from 5 to 100 &mgr;m, medium waved structure whose average pore size ranges from 0.5 to 5 &mgr;m and small waved structure whose average pore size ranges from 0.01 to 0.2 &mgr;m, which are superimposed.

Abstract: A method for treating a photosensitive lithographic printing plate, which comprises exposing the photosensitive lithographic printing plate to laser light, developing with a developer containing an alkali metal silicate and then carrying out post-exposure treatment, said photosensitive lithographic printing plate being prepared by forming a photopolymerizable photosensitive layer having a film thickness of from 1.2 to 4 g/m2 and further forming a protective layer having a film thickness of from 2 to 8 g/m2 on a support having a centerline average height (Ra) of at least 0.35 &mgr;m.

Abstract: A thermosensitive composition consisting of a mixture of polyacrylic acid, a salt of a long chain fatty acid such as silver behenate, an infra-red absorbent and modifiers such as additional polymers and fillers. Both the water solubility and affinity to water and oil changed when composition is heated.

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 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: The invention is a directly imageable waterless planographic printing plate precursor comprising: at least a heat insulating layer, a heat sensitive layer, and an ink repellent layer that are provided in that order on a substrate, wherein a transmittance of the heat insulating layer for a light having a wavelength within a range of 400 to 650 nm is at most 15% over the entire range of the wavelength. The invention provides a directly imageable waterless planographic printing plate precursor that allows measurement of the dot area ratio on the printing plate with a densitometer or the like.

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

Abstract: A presensitized plate for preparing a lithographic printing plate comprises a substrate provided thereon with a light-sensitive layer containing a fluoro-aliphatic group-containing copolymer prepared by copolymerizing at least (A) an addition polymerizable monomer having, on a side chain, a fluoro-aliphatic group in which hydrogen atoms are replaced with fluorine atoms and (B) a (meth)acrylate having an ester chain represented by a specific general formula. The use of the foregoing specific fluorine atom-containing polymer permits the formation of a light-sensitive layer having uniform surface condition without causing abnormality in the surface quality due to the foaming phenomenon observed during the production and also permits the production of a positive light-sensitive resin composition having excellent solubility and dispersibility in a developer.

Abstract: A method for preparing a lithographic printing plate which comprises imagewise exposing to light a presensitized plate useful for making a lithographic printing plate having an intermediate layer and a photosensitive layer on an aluminum substrate in this order and developing the imagewise exposed plate with a developer, wherein said intermediate layer comprises a polymer compound comprising at least a structure unit having an acid group and a structure unit having an onium group and said developer comprises an inorganic alkali salt and a nonionic surfactant having polyoxyalkylene ether group and pH of the developer ranges from 11.0 to 12.7. The method provides a lithographic printing plate, which shows good contrast between an image area and non-image area, no background contamination during printing, good stability with time and good printing durability.

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 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 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: An offset plate sensitive to UV or visible light, prepared simply and imaged digitally therewith in a CTP method, and also processed in a simple manner. The plate is provided as a photopolymer plate with increased sensitivity, and is used in a simple imaging-on-press system, using the surface of a lithographic printing cylinder itself as a plate substrate.

Abstract: Provided is a heat-sensitive lithographic printing plate comprising a support having thereon an undercoat layer and a heat-sensitive layer in this order, with at least one of the undercoat layer and the heat-sensitive layer comprising polymer hollow microspheres having voids on the inside, or a heat-sensitive lithographic printing plate comprising a support having thereon a heat-sensitive layer, with the heat-sensitive layer comprising polymer hollow microspheres having voids on the inside.

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: The invention relates to a method for producing laser-engravable flexographic printing elements on flexible metallic supports comprising a cross-linked elastomeric layer and an absorber for laser radiation. The invention also relates to a method for producing flexographic printing plates by means of laser engraving using flexographic printing elements of the aforementioned type, and to flexographic printing plates produced using such a method.

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

Abstract: Multi-layer thermally imageable elements, useful as a lithographic printing plate precursors, are disclosed. The elements contain a top layer, an absorber layer that contains a photothermal conversion material and a hydrophilic substrate. An optional underlayer may also be present between the absorber layer and the hydrophilic substrate. The elements can be thermally imaged and processed with an aqueous alkaline developer.

Abstract: A coating solution useful in the preparation of printing plate precursors comprises:

Abstract: A heat-sensitive lithographic printing plate precursor is disclosed comprising a polymer which is soluble in an aqueous alkaline solution and which comprises at least one chromophoric moiety having a light absorption maximum in the wavelength range between 400 and 780 nm. Such materials show no dye stain after processing in areas where the coating has been removed by an alkaline developer.

Abstract: Copolymers containing the units A, B, C, D and optionally E are used to prepare radiation sensitive compositions and lithographic printing plates.

Abstract: A lithographic printing plate precursor comprises a hydrophilized aluminum support having provided thereon an interlayer and a photopolymerizable photosensitive layer, the interlayer containing a polymer having a cationic group and a radical reactive group or containing a compound capable of forming a complex with ammonium, and the photopolymerizable photosensitive layer containing a photopolymerization initiator, a compound having an addition polymerizable ethylenically unsaturated bond, and a polymer binder.

Abstract: Imagable precursors for masks and for electronic parts comprise a polymeric layer applied to a substrate. The layer comprises at least one polymer having infra-red absorbing groups carried as pendent groups on the polymer backbone. Certain infra-red absorbing groups may also act to insolubilize the polymer in a developer, until it is imagewise exposed to infra-red radiation. Imagewise application of heat, resulting from imagewise exposure of the precursor to infra-red radiation, renders the polymer layer more soluble in the developer than prior to exposure to the infra-red radiation.

Abstract: A photosensitive resin laminate comprising at least a support, a photosensitive resin layer and an IR ablation layer, wherein the IR ablation layer comprises an IR absorbent metal layer which is disposed in contact with the photosensitive resin layer.

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.

Abstract: According to the present invention there is provided a heat-sensitive imaging material for making lithographic printing plates which require no processing. The heat-sensitive imaging element comprises on a lithographic base having a hydrophilic surface a metallic or metal oxide layer and on top thereof an oleophobic oleophilic polymeric layer having a thickness of less than 5 &mgr;m and comprising a polymer containing phenolic groups.