Abstract: The invention provides a planographic printing plate precursor, utilizing a support member having a hydrophilic surface excellent in hydrophilicity and durability, providing effects of improving scumming in the printing operation and capable of forming large numbers of prints of high image quality even under severe printing conditions. The precursor comprises a support including an aluminum substrate and a hydrophilic layer disposed thereon, the hydrophilic layer formed by chemically bonding a hydrophilic polymer, which includes a reactive group able to chemically bond to a surface of the aluminum substrate directly or via a structural component comprising a crosslinked structure; and a positive working recording layer disposed on the support and including a light-absorbing and heat-generating material, and a polymer compound, which is insoluble in water and soluble in alkali, wherein solubility of the recording layer in an alkaline aqueous solution increases upon exposure to light.

Abstract: A lithographic printing plate precursor comprising an aluminum substrate, an image-recording layer and a hydrophilic film, the aluminum substrate being subjected to an electrochemical surface-roughening treatment in an aqueous solution comprising hydrochloric acid and provided with the hydrophilic film having a heat conductivity of 0.05 to 0.5 W/mK and/or at least one of a density of 1,000 to 3,200 kg/m3 and a porosity of 20 to 70%; and a lithographic printing plate precursor comprising an aluminum substrate, an image-recording layer and a hydrophilic film, the aluminum substrate having a surface-roughened shape comprising a small pit wherein an average opening size of the small pit is 0.01 to 3 ?m and a ratio of an average depth of the small pit to the average opening size is 0.1 to 0.5, and being provided with the hydrophilic film having a heat conductivity of 0.05 to 0.5 W/mK and/or at least one of a density of 1,000 to 3,200 kg/m3 and a porosity of 20 to 70%.

Abstract: A lithographic printing plate precursor is disclosed, comprising a metal support having formed thereon an anodic oxide film, and an image-forming layer containing a light-to-heat converting agent, or a light-sensitive layer capable of image-forming with infrared laser exposure provided in this order from the support.

Abstract: The present invention relates to a planographic printing plate precursor, in which an intermediate layer comprising a polymer having a lactone group and a recording layer are successively provided on or over a support. The polymer preferably has not only the lactone group but also an acidic group.

Abstract: Disclosed is a support for a lithographic printing plate, wherein an adhering amount of a rare-earth element atom to a surface thereof is 0.1 to 20 mg/mg2, and a presensitized plate provided with an image recording layer on the support for a lithographic printing plate. The presensitized plate achieving both high scum resistance and long press life can be realized, which is the same in the case the image recording layer containing an infrared absorbent, where scum would easily occur, is provided onto the support.

Abstract: Disclosed is a presensitized plate, comprising: a support for a lithographic printing plate obtainable by forming on an aluminum plate at least an anodized layer, then performing sealing treatment; and an image recording layer which is provided on the support, includes an infrared absorber (A), a polymerization initiator (B), and a polymerizable compound (C), and can be removed with printing ink and/or dampening water. The presensitized plate of the present invention exhibits excellent on-machine developability, sensitivity, scumming resistance, chemical resistance and press life.

Abstract: Disclosed is a presensitized plate, having an anodized layer and recording layer provided on a support for a lithographic printing plate, wherein the anodized layer is provided by subjecting an aluminum plate to graining and anodizing treatments. The presensitized plate has wide development latitude, makes it difficult for scratch-like non-image portions to be generated and facilitates handling in usual operation.

Abstract: The present invention provides a planographic printing plate precursor having an intermediate layer containing a polymer having a structure represented by the formula (I) at its side chain and an infrared laser photosensitive positive recording layer, disposed on a support in this order. In the formula (I), Y represents a connecting group connected with a main chain of the polymer, R1 represents a hydrogen atom or a hydrocarbon group and R2 represents a divalent hydrocarbon group.

Abstract: The present invention relates to a planographic printing plate precursor, in which an intermediate layer comprising a polymer having a lactone group and a recording layer are successively provided on or over a support. The polymer preferably has not only the lactone group but also an acidic group.

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: The present invention relates to a preparation method for a lithographic printing plate, which comprises forming a presensitized plate by coating a photosensitive layer or thermosensitive layer on an aluminum substrate treated with an aqueous solution after optionally anodized and developing the presensitized plate with a developer comprising no silicate, wherein the aqueous solution comprises at least one compound selected from the group consisting of nitrite group-containing compound, fluorine atom-containing compound and phosphorous atom-containing compound, in the proviso that when the at least one compound is fluorine atom-containing compound, the treated aluminum substrate has a surface which satisfies the formula: 0.30≦A/(A+B)≦0.

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 heat-sensitive lithographic printing plate precursor which comprises a substrate having thereon an anodic oxidation layer, with the printing plate precursor comprising a hydrophilic layer containing at least one kind of fine particles selected from the group consisting of heat-fusible hydrophobic thermoplastic fine particles, finely divided polymers having thermally reactive functional groups and microcapsules in which compounds having heat-reactive functional groups are encapsulated, and with the anodic oxidation layer having a surface over which micropores having an average pore size of 6 to 40 nm are uniformly distributed.

Abstract: A 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: The invention provides a planographic printing plate precursor, utilizing a support member having a hydrophilic surface excellent in hydrophilicity and durability, providing effects of improving scumming in the printing operation and capable of forming large numbers of prints of high image quality even under severe printing conditions.

Abstract: Disclosed is a support for a lithographic printing plate obtainable by performing at least graining treatment on an aluminum plate, having on its surface thereof, a grain shape with a structure in which a grained structure with medium undulation of 0.5 to 5 &mgr;m average aperture diameter and a grained structure with small undulation of 0.01 to 0.2 &mgr;m average aperture diameter are superimposed, and a presensitized plate provided with an image recording layer on the support for a lithographic printing plate. By using this presensitized plate, a balance between scum resistance and press life when a lithographic printing plate is produced therefrom, which has been in a trade-off relation in the past, can be maintained at a high level.

Abstract: A lithographic printing plate precursor comprising an aluminum substrate, an image-recording layer and a hydrophilic film, the aluminum substrate being subjected to an electrochemical surface-roughening treatment in an aqueous solution comprising hydrochloric acid and provided with the hydrophilic film having a heat conductivity of 0.05 to 0.5 W/mK and/or at least one of a density of 1,000 to 3,200 kg/m3 and a porosity of 20 to 70%; and a lithographic printing plate precursor comprising an aluminum substrate, an image-recording layer and a hydrophilic film, the aluminum substrate having a surface-roughened shape comprising a small pit wherein an average opening size of the small pit is 0.01 to 3 &mgr;m and a ratio of an average depth of the small pit to the average opening size is 0.1 to 0.5, and being provided with the hydrophilic film having a heat conductivity of 0.05 to 0.5 W/mK and/or at least one of a density of 1,000 to 3,200 kg/m3 and a porosity of 20 to 70%.

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 comprising a support for a lithographic printing plate including an anodized layer formed on an aluminum plate and a recording layer recordable by infrared laser exposure on the support, wherein in a section of the anodized layer after the recording layer is provided, an atomicity ratio of carbon to aluminum (C/Al) represented by Auger Electron Spectroscopic analysis is 1.0 or less. In the case of being used as an on-machine development type, it exhibits a good on-machine development characteristic, a high sensitivity, a high press life, and high scum resistance during printing and while left (ink discharging). In the case of being used as a conventional thermal positive or negative working type, it exhibits an efficient use of heat for image formation, a high sensitivity, a high press life, and a slight possibility of scum occurrence at non-image areas.