Provided are a lithographic printing plate precursor having a support, an image recording layer, and an overcoat layer in this order, in which the overcoat layer includes a water-soluble polymer and particles, a melting point of the particles is in a range of 70 C. to 150 C., and a volume average particle diameter of the particles is greater than 0.7 m and a method of producing a lithographic printing plate obtained by using the lithographic printing plate precursor.

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 opposite to a side where the image recording layer is provided is in a range of 0.3 m to 20 m; a method of producing the lithographic printing plate precursor; a lithographic printing plate precursor laminate formed of the lithographic printing plate precursor; and a lithographic printing method.

Provided are a lithographic printing plate precursor including 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.; and a method of producing a lithographic printing plate obtained by using the lithographic printing plate precursor.

It is preferable that the 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.

Provided is a lithographic printing plate precursor having: a support; and an image-recording layer as an outermost surface layer on the support, in which the image-recording layer includes a hydrophilic polymer, an ion intensity derived from the hydrophilic polymer has a maximum value I1, the ion intensity being measured by a time-of-flight secondary ion mass spectrometry in such a manner that cutting is carried out from an image-recording layer surface in a direction of the support by an Ar gas cluster ion beam method, a ratio d0/d1 of a thickness d0 of the image-recording layer to a depth d1 from an outermost layer at which the I1 is obtained is 2.0 or more, and a ratio I1/I0 of the I1 to an ion intensity I0 derived from the hydrophilic polymer at a depth from the outermost layer of the d0 is 1.5 or more.

Provided are a lithographic printing plate precursor having an image-recording layer on a hydrophilic support, in which the image-recording layer includes a. polymer having a constituent unit derived from a monomer having a solubility parameter of 20 MPa.sup.1/2 or more, an infrared absorber, and a polymer particle; a resin composition for producing a lithographic printing plate precursor including the polymer, an infrared absorber, and a polymer particle; and a method for producing a lithographic printing plate in which the lithographic printing plate precursor is used.

Provided are a lithographic printing plate precursor having an image-recording layer on an aluminum support, in which the image-recording layer contains a polymerization initiator, an infrared absorber, a polymer particle, and a polymerizable compound, and the polymerizable compound has a) a molecular weight of 1,500 to 3,000, b) a double bond equivalent of 200 or less, and c) a CLog P of 9 or less and a method for producing a lithographic printing plate in which the lithographic printing plate precursor is used.

Provided are a lithographic printing plate precursor comprising: an image-recording layer on a support, in which the image-recording layer includes a dye compound having a decomposable group that is decomposed by an acid, heat, or both and a structure in which decomposition of the decomposable group opens a ring or desorbs a leaving group and an electron-donating polymerization initiator, a method for producing a lithographic printing plate in which the lithographic printing plate precursor is used, and a color-developing composition including a dye compound having a decomposable group that is decomposed by an acid, heat, or both and a structure in which decomposition of the decomposable group opens a ring or desorbs a leaving group and an electron-donating polymerization initiator.

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; a method of producing a lithographic printing plate precursor; 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.

Provided are a lithographic printing plate precursor having an image-recording layer on a hydrophilic support, in which the image-recording layer contains an infrared absorbing dye that decomposes by exposure to an infrared ray and a color developer that develops color due to the exposure to an infrared ray and a method for producing a lithographic printing plate in which the lithographic printing plate precursor is used.

Provided are a lithographic printing plate precursor having an image-recording layer on a hydrophilic support, in which the image-recording layer includes an organic polymer particle, and the organic polymer particle is a reaction product obtained by at least reacting an aromatic polyvalent isocyanate compound having a structure represented by Formula PO and water, a method for making a lithographic printing plate having excellent printing resistance in the case of using an ultraviolet-curable ink in printing, a new organic polymer particle, and a resin composition including the organic polymer particle.

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