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 organic particle containing a resin that has a constitutional unit A having a cation moiety and a constitutional unit B having an anion moiety; and a method of preparing a planographic printing plate using the planographic printing plate precursor.

Provided are a lithographic printing plate precursor including a support, and an image recording layer on the support, in which the image recording layer contains organic particles containing an addition polymerization type resin that has a constitutional unit A having a hydrogen bond-donating site, and a content of the constitutional unit A in the addition polymerization type resin is greater than 20% by mass with respect to a total mass of the addition polymerization type resin; and a method of preparing a lithographic printing plate using the lithographic printing plate precursor.

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.

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.

IR-sensitive lithographic printing plate precursors provide a stable print-out image using a unique IR-sensitive image-recording layer. The IR radiation-sensitive layer includes: (1) a free radical initiator composition with an electron-donating agent and one or more iodonium cations; (2) a free radically polymerizable composition; and (3) a color-changing compound of Structure (I) having an indene ring in the conjugated chain between the aromatic terminal groups. The IR radiation-sensitive composition and layer also contains one or more borate ions such that the molar ratio of one or more borate ions to the one or more iodonium ions is at least 0.5:1. After IR imaging, these precursors exhibit desirable printout images both fresh and after dark storage. The precursors can be developed on-press.

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.

Provided are: a lithographic printing plate precursor having a support and an image-recording layer on the support, in which the image-recording layer contains an onium polymerization initiator, a borate compound, an infrared absorber, a chromogenic agent, and a compound A which is an onium salt formed of a cation having a shape index lower than a shape index of a cationic moiety of the onium polymerization initiator; a method of preparing a lithographic printing plate using the lithographic printing plate precursor; and a lithographic printing method.

A lithographic printing plate precursor is disclosed including a support and a coating comprising a photopolymerisable layer including a polymerisable compound and a photoinitiator, characterized in that the coating comprises a hydrophilic adhesion promoting copolymer including at least one monomeric unit according to Formula I and at least one monomeric unit according to Formula II; and at least one group and/or moiety including a phosphor atom.

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