Provided are a planographic printing plate precursor including a support, and an image recording layer on the support, in which the image recording layer contains an infrared absorbing agent, a polymerization initiator, and a core-shell particle, a core portion of the core-shell particle contains a resin A containing a functional group A, and a shell portion of the core-shell particle contains a resin B containing a functional group B that is bondable to or interactable with the functional group A and a dispersion group; a method of preparing a planographic printing plate using the planographic printing plate precursor; and a planographic printing method carried out using the planographic printing plate precursor.

A lithographic printing plate precursor including a photopolymerisable coating and an overcoat layer provided on top of said layer, characterized in that the overcoat layer includes a compound comprising at least one moiety having a structure according to Formula (I): (I).

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The invention relates to an imageable coating layer, thermal negative-working lithography printing plate, and platemaking method. The coating layer includes constituents in parts by weight: a radically polymerizable compound 20-60 parts, a radiation-absorbing compound 0.5-12 parts, a free radical initiator 1-25 parts, a binding agent 10-70 parts, and a development accelerator 0.5-15 parts. The platemaking method includes the steps: S1, preparing a printing plate precursor that includes a substrate having a hydrophilic surface or is provided with a hydrophilic layer and imageable coating layer covering the substrate; S2, patternedly exposing the printing plate precursor, forming an exposed area and an unexposed area; and S3, removing the unexposed area via a development process. The employment of the imageable coating layer and the plate making method allows the implementation of a flexible development process of “on-press development” or “off-press development” and produces a printing plate provided with great printing performance.

A lithographic printing plate precursor is disclosed including a support and a coating comprising a photopolymerisable layer including a polymerisable compound, a photoinitiator, and an infrared absorbing compound including a long chain linear or branched alkyl group.

The present invention provides a printing plate precursor including a layer which includes particles and is provided at a printing surface side of an aluminum support, in which a modulus of elasticity of the particles is 0.1 GPa or more, and in a case where a Bekk smoothness of an outermost layer surface at the printing surface side is denoted by A second, a specific expression (1) is satisfied; a printing plate precursor laminate; a method for making a printing plate; and a printing method.

A lithographic printing plate precursor is disclosed including a support and a coating comprising (i) a photopolymerisable layer including a polymerisable compound and a photoinitiator, and a toplayer provided above the photopolymerisable layer; characterized in that the toplayer has a thickness comprised between 0.1 g/m.sup.2 and 1.75 g/m.sup.2 and includes an infrared absorbing compound which includes a thermocleavable group which transforms into a group which is a stronger electrondonor upon exposure to heat and/or IR radiation, and is capable of forming a printout image upon exposure to heat and/or IR radiation.

Lithographic printing plate precursors have an aluminum-containing substrate prepared using two anodizing processes to provide an inner aluminum oxide layer of average dry thickness of 300-3,000 nm and a multiplicity of inner micropores of average inner micropore diameter of ≤100 nm. An outer aluminum oxide layer is provided with a multiplicity of outer micropores of average outer micropore diameter of 15-30 nm and a dry thickness of 30-650 nm. A hydrophilic layer is disposed on the outer aluminum oxide layer at 0.0002-0.1 g/m.sup.2 and has a (1) compound having an ethylenically unsaturated polymerizable groups; a —OM group connected directly to a phosphorus atom, wherein M represents hydrogen, sodium, potassium, or aluminum; and (2) one or more hydrophilic polymers having (a) recurring units comprising an amide group, and (b) recurring units having an —OM′ group that is directly connected to a phosphorus atom, wherein M′ represents hydrogen, sodium, potassium, or aluminum.

A method of lithographic plate making is disclosed wherein a plate precursor is exposed to laser radiation in the wavelength range from 350 to 450 nm, said plate precursor comprising a hydrophilic support and a photopolymerizable or photocrosslinkable image recording layer, and then processed on-press by supplying fountain and ink. The exposure produces a visible image having a 1976 CIELAB color distance ΔE between exposed and non-exposed areas of at least 2.5.

A method for processing a heat-sensitive positive-working lithographic printing plate material is disclosed which comprises at least two layers: —a first layer comprising an oleophilic resin and/or a vinyl acetal (co)polymer; —a second layer comprising a (co)polymer which is located between the support and the first layer; comprising the steps of: —treating the plate material with an alkaline development solution, —treating the plate material with a first gum solution and consecutively with a second gum solution which are configured as a cascade whereby the second gum solution overflows into the first gum solution; and which gum solutions include a buffer; characterized in that the pH of the first gum solution reaches a steady state value above the pKa value of the (co)polymer present in the second layer.

A lithographic printing plate precursor includes an image recording layer on a support, in which the lithographic printing plate precursor has projections which are discontinuously formed on a surface of an outermost layer on a side where the image recording layer is provided, and a melting point of each projection is in a range of 70° C. to 150° C. A method of producing a lithographic printing plate includes a step of image-wise exposing the lithographic printing plate precursor to form an exposed portion and an unexposed portion, and a step of supplying at least one of printing ink or dampening water to remove the unexposed portion.