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 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.

A planographic printing plate precursor includes: a support; and an image recording layer which includes a radical initiator, a radical polymerizable component, and a radiation absorption compound, and in which the image recording layer shows two or more peaks of a radical generation amount in a radical generation amount-versus-time curve after exposure to image forming radiation, in which the radical initiator includes an electron-donating radical initiator and an electron-accepting radical initiator, and the radiation absorption compound comprises a compound represented by the following Formula 1.

##STR00001##

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 planographic printing plate precursor having an image recording layer on a support, and an overcoat layer in this order, in which the overcoat layer includes particles, the overcoat layer is an outermost layer, and an occupation area ratio of the particles in a surface of the overcoat layer is 30% by area or more; and a method of producing a planographic printing plate obtained by using the planographic printing plate precursor.

A planographic printing plate precursor includes: a hydrophilic support; and an image recording layer which contains an organic-inorganic hybrid particle (A) and an infrared-ray absorbent (B) on the hydrophilic support, and the organic-inorganic hybrid particle (A) is an organic-inorganic hybrid particle in which an inorganic particle (a) containing a hydroxyl group and an organic component (b) are linked to each other through a linking group (c) having a urethane bond or a urea bond.

The invention is directed to a lithographic printing plate precursor including, in the following order: a support; an image-recording layer containing a radical polymerizable compound and a radical polymerization initiator; and a protective layer containing a star polymer, and the star polymer is preferably a polymer in which from 3 to 10 polymer chains are branched from a central skeleton.

A lithographic printing plate precursor is disclosed which includes a support and a coating comprising a photopolymerisable layer including a polymerisable compound, an initiator and a pH sensitive colorant precursor and a protective overcoat layer provided above the photopolymerisable layer including a heat sensitive color-forming IR dye, which upon exposure to heat and/or light forms a print-out image which remains stable or increases during storage of the precursor in light or dark environment.