Disclosed is a heat-sensitive processless planographic printing plate material containing a thermosensitive protection layer. The planographic printing plate material sequentially comprises a supporting body, a hydrophilic layer, a heat-sensitive layer and a thermosensitive protection layer from the bottom up. The thermosensitive protection layer therein can not only isolate oxygen and protect the heat-sensitive layer from oxygen inhibition, but can also sense heat and allow a polymerization reaction to take place. Thus the binding force between same and the next layer is improved, so that the precision of printing plate images is high, the development performance is good, and the pressrun is high.

A laminated lithographic printing plate comprising an aluminum layer having a first side and a second side, an aluminum oxide layer coating the first side aluminum layer, optionally a second aluminum oxide layer coating the second side of the aluminum layer, an image forming layer coating the first aluminum oxide layer, an adhesive layer adhering to the second side of the aluminum layer or to said second aluminum oxide layer when second aluminum oxide layer is present, and a base layer coating the adhesive layer is provided.

A method of preparing a lithographic printing plate includes the steps printing a liquid on a lithographic support to form a printing area which corresponds to a raster image, wherein the raster image includes a section which has a tone-value from 90% to 100%, and the jetted liquid droplets for this section, on a corresponding part from the printing area on the lithographic support, are contactless with each other.

Provided are a planographic printing plate precursor, a laminate thereof, and a method of producing a planographic printing plate precursor capable of satisfying all purposes for eliminating interleaving paper used for preventing scraping and peeling, preventing adhesion, imparting a plate-separating property for preventing multiple-plate feeding, and preventing scratches. The planographic printing plate precursor which includes a polymer layer on a surface of a belt-like support 12 includes a back coat layer 70 having an arithmetic average surface roughness Ra of 0.5 m or greater due to a surface roughness structure in which thin film portions 60 and thick film portions 62 are continuously formed on a rear surface of the belt-like support 12.

Provided are a lithographic printing plate precursor including an aluminum support, and an image recording layer on the aluminum support, in which the aluminum support includes an anodized film on a surface of the image recording layer side, the anodized film has micropores extending in a depth direction from the surface of the anodized film on the image recording layer side, an average pore diameter of the micropores in the surface of the anodized film is greater than 0 m and 0.03 m or less, an average maximum diameter of the micropores inside the anodized film is in a range of 0.04 m to 0.30 m, an average value A nm of thicknesses of surface opening portions and an average value B nm of thicknesses of internal maximum diameter portions satisfy a relationship of 2.5B/A28.0, and the image recording layer contains an acid color former; a method of preparing a lithographic printing plate using the lithographic printing plate precursor; and a lithographic printing method.

Provided are a lithographic printing plate precursor including a hydrophilized aluminum support, and a water-soluble or water-dispersible negative type image recording layer provided on the aluminum support, in which an arithmetic average height Sa of a surface of an outermost layer on a side where the image recording layer is provided is in a range of 0.3 m to 20 m or in which Expression (1) and Expression (2) are satisfied in a case where a Bekk smoothness of a surface of an outermost layer on a side where the image recording layer is provided is set as a seconds and a Bekk smoothness of a surface of an outermost layer on a side opposite to a side where the image recording layer is provided is set as b seconds; a method of producing the same; a lithographic printing plate precursor laminate formed of the lithographic printing plate precursor; a plate-making method for a lithographic printing plate; and a lithographic printing method.

a1000,b1000(1)

1/a+1/b0.002(2)

A lithography printing plate and method for using the same are disclosed. In one embodiment, the printing plate comprises a metallic plate having top and bottom sides with one or more coating layers on the first side of the metallic plate. A layer is attached to the second side of the metallic plate, thereby forming a laminate.

The present invention provides an on-press development type lithographic printing plate precursor including, in the following order, a support, an image-recording layer, and a protective layer, in which the image-recording layer contains a) a polymerizable compound, b) an infrared absorber, c) a polymerization initiator, and d) a color forming substance precursor, and the protective layer contains an ultraviolet absorber, and a method of preparing a printing plate.

The present invention provides a support for a lithographic printing plate, from which a lithographic printing plate precursor having excellent scratch resistance can be obtained by combining the support with an image recording layer, a lithographic printing plate precursor, and a method of producing a lithographic printing plate. The support for a lithographic printing plate according to the present invention, including an aluminum plate, and an anodized aluminum film disposed on the aluminum plate, in which a plurality of projections are present on a surface of the support for a lithographic printing plate on a side of the anodized film, an average value of equivalent circular diameters of the projections in a cut surface at a position that is 0.5 ?m greater than a position of the projections with an average height is in a range of 3.0 to 10.0 ?m, and a density of the projections with a height of 0.5 ?m or greater from the position of the projections with the average height is in a range of 3,000 to 9,000 pc/mm.sup.2.

The present invention aims at providing a lithographic printing plate precursor, a lithographic printing plate manufacturing method, a printing method and an aluminum support manufacturing method that enable the resulting lithographic printing plate to have a long tiny dot press life. The lithographic printing plate precursor of the invention is a lithographic printing plate precursor having an aluminum support and an image recording layer disposed above the aluminum support. When measured over a 400 m400 m region of a surface of the aluminum support on the image recording layer side using a three-dimensional non-contact roughness tester, pits with a depth from centerline of at least 0.70 m are present at a density of at least 3,000 pits/mm.sup.2; and a surface area ratio S is not less than 35%, the surface area ratio S being determined using an actual area S.sub.x obtained, through three-point approximation, from three-dimensional data acquired by measurement at 512512 points in 25 m square of the surface of the aluminum support on the image recording layer side by means of an atomic force microscope and a geometrically measured area S.sub.o.