A lithographic printing plate precursor has an infrared radiation-sensitive image-recording layer containing an IR absorber, and an ozone-blocking material of 1500 or less molecular weight and has structure (I), (II), or (III):

##STR00001##

wherein R is a hydrocarbon having 14-30 carbon atoms; m is 1 or 2; n is 1-6; the sum of m and n is >2 and <8; and A is a multivalent organic moiety free of R and OH groups and has a valence m+n;

##STR00002##

wherein R.sub.1 and R.sub.2 are alkyl groups of 14-22 carbon atoms, and o is 1-3;

R.sub.3C(═O)NR.sub.4R.sub.5   (III)

wherein R.sub.3 is an alkenyl with a C═C bond within a carbon-carbon chain of 16-30 carbons, and R.sub.4 and R.sub.5 are hydrogen or unsubstituted alkyls of 1-4 carbon atoms. Such ozone-blocking materials can be used to protect infrared radiation-sensitive dyes that may be degraded by ozone and thus improve imaging sensitivity.

A lithographic printing plate precursor is disclosed including a support and a coating comprising (i) a photopolymerisable layer including a polymerisable compound and an optionally substituted trihaloalkyl sulfone photoinitiator, and (ii) a toplayer provided above the photopolymerisable layer; characterized in that the toplayer includes an infrared absorbing dye capable of forming a print-out image upon exposure to heat and/or IR radiation.

A lithographic printing plate precursor is disclosed including a support and a coating comprising (i) a photopolymerisable layer including a polymerisable compound, a borate compound and/or a photoinitiator and (ii) a toplayer provided above the photopolymerisable layer; characterized in that the toplayer has a thickness comprised between 0.1 g/m2 and 1.75 g/m2 and includes an infrared absorbing compound which includes a thermocleavable group which transforms into a group which is a stronger electron-donor upon exposure to heat and/or IR radiation, and is capable of forming a print-out image upon exposure to heat and/or IR radiation.

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 plates are provided by imagewise exposing negative-working lithographic printing plate precursors having one or more radiation-sensitive imageable layers, followed by contacting with a processing solution that contains up to 10 weight % of one or more compounds represented by Structure (I) shown as follows:

R.sup.1—C(═O)—N(R.sup.2)—R.sup.3   (I)

wherein R.sup.1, R.sup.2, and R.sup.3 independently represent hydrogen or a substituted or unsubstituted hydrocarbon group, or two or three of R.sup.1, R.sup.2, and R.sup.3 are combined to form one or more cyclic rings, and the total number of carbon atoms in the Structure (I) molecule is at least 7 and up to and including 33. Both negative-working and positive-working lithographic precursors can be imaged and processed using this processing solution using one or more successive applications of the same or different processing solution. The processing solution can be derived from a corresponding processing solution concentrate that can also be used for replenishment.

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 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.

Provided are a planographic printing plate precursor including an aluminum support, and an image recording layer and a protective layer which are provided on the aluminum support in this order, in which a thickness of the protective layer is 0.2 μm or greater, and Expression (1) is satisfied in a case where 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 denoted by b seconds; a planographic printing plate precursor laminate; a plate-making method for a planographic printing plate; and a planographic printing method.

A planographic printing plate precursor containing in the following order: an aluminum support; an image recording layer; and a protective layer, in which a thickness of the protective layer is 0.2 μm or greater, and in a case where a Bekk smoothness of a surface of an outermost layer at a side where the image recording layer is provided is 1000 seconds or less.

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.