The present invention provides a printing plate precursor including a layer which includes a polymer and is provided on a printing surface side of an aluminum support, and a layer which includes particles and is provided on a side opposite to the printing surface side, 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 on the side opposite to the printing surface side is denoted by b second, a specific expression (1) is satisfied; a printing plate precursor laminate; a method for making a printing plate; and a printing method.

Lithographic printing plate precursors are prepared with a unique aluminum-containing substrate and one or more radiation-sensitive imageable layers. The aluminum-containing substrate is prepared by three separate and sequential anodizing processes to provide an inner aluminum oxide layer having an average dry thickness (T.sub.i) of 500-1,500 nm and a multiplicity of inner pores having an average inner pore diameter (D.sub.i) larger than 0 and <15 nm. A formed middle aluminum oxide layer has a dry thickness (T.sub.m) of 60-300 nm and a multiplicity of middle pores of average middle pore diameter (D.sub.m) of 15-60 nm, arranged over the inner aluminum oxide layer. A formed outer aluminum oxide layer comprises a multiplicity of outer pores having an average outer pore diameter (D.sub.o) of 5-35 nm and an average dry thickness (T.sub.o) of 30-150 nm, arranged over the middle aluminum oxide layer. D.sub.m is larger than D.sub.o that is larger than D.sub.i.

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 includes an leuco dye and a hydrophobic binder.

Lithographic printing plate precursors are prepared with a unique aluminum-containing substrate and one or more radiation-sensitive imageable layers. The aluminum-containing substrate is prepared by three separate and sequential anodizing processes to provide an inner aluminum oxide layer having an average dry thickness (T.sub.i) of 500-1,500 nm and a multiplicity of inner pores having an average inner pore diameter (D.sub.i) larger than 0 and <15 nm. A formed middle aluminum oxide layer has a dry thickness (T.sub.m) of 60-300 nm and a multiplicity of middle pores of average middle pore diameter (D.sub.m) of 15-60 nm, arranged over the inner aluminum oxide layer. A formed outer aluminum oxide layer comprises a multiplicity of outer pores having an average outer pore diameter (D.sub.o) of 5-35 nm and an average dry thickness (T.sub.o) of 30-150 nm, arranged over the middle aluminum oxide layer. D.sub.m is larger than D.sub.o that is larger than D.sub.i.

The present invention provides a printing plate precursor, a method of producing a printing plate, and a printing method with excellent stain resistance and deinking capability after being left to stand at the time of obtaining a printing plate. The printing plate precursor of the present invention is a printing plate precursor including an aluminum support, and a functional layer which is disposed on the aluminum support, in which the aluminum support includes an aluminum plate and an aluminum anodized film disposed on the aluminum plate, the anodized film is positioned closer to the functional layer than the aluminum plate is, the anodized film has micropores extending in a depth direction from a surface of the functional layer side, and an average diameter of the micropores in the surface of the anodized film is in a range of 13 nm to 100 nm, the printing plate precursor contains a hydrophilizing agent in a region on a plate surface of the functional layer side which extends to a distance of 5 mm inward from two facing end portions of the printing plate precursor, and a content of the hydrophilizing agent per unit area in the region is greater than a content of the hydrophilizing agent per unit area in a region other than the region by 10 mg/m.sup.2 or greater.

Provided are a printing plate precursor including a support, a layer containing a polymer on a printing surface side on the support, and a layer containing tabular particles on a non-printing surface side opposite to the layer containing a polymer in a state of sandwiching the support therebetween, and a printing plate precursor laminate which is obtained by laminating a plurality of the printing plate precursors, wherein the printing plate precursor laminate is formed such that an outermost layer on a surface where the layer containing the polymer is provided and an outermost layer on a surface where the layer containing the tabular particles is provided are laminated by being brought into direct contact with each other.

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 on the support, in which the image-recording layer has an infrared absorber, a polymerization initiator, a polymerizable compound 1, a polymerizable compound 2, and a polymerizable compound 3, in which a molecular weight of the polymerizable compound 1 is less than 1,000, a weight-average molecular weight of the polymerizable compound 2 is 1,000 or more and 3,000 or less, and a weight-average molecular weight of the polymerizable compound 3 is more than 3,000 and 15,000 or less.

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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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 particle including an addition polymerization-type resin having a hydrophilic structure and a crosslinking structure, a method for producing a lithographic printing plate in which the lithographic printing plate precursor is used, a polymer particle including an addition polymerization-type resin having a hydrophilic structure and a crosslinking structure, and a composition including the polymer particle.