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 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.

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.

Disclosed is a heat-sensitive processless planographic printing plate material containing a thermosensitive protection layer. The planographic printing plate material sequentially comprises a supporting body, a hydrophilic layer, a heat-sensitive layer and a thermosensitive protection layer from the bottom up. The thermosensitive protection layer therein can not only isolate oxygen and protect the heat-sensitive layer from oxygen inhibition, but can also sense heat and allow a polymerization reaction to take place. Thus the binding force between same and the next layer is improved, so that the precision of printing plate images is high, the development performance is good, and the pressrun is high.

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.

Lithographic printing plate precursors are prepared with a unique substrate using two separate anodizing processes to provide an inner aluminum oxide layer of average dry thickness (T.sub.i) of 650-3,000 nm and a multiplicity of inner micropores of average inner micropore diameter (D.sub.i) of 15 nm. An outer aluminum oxide layer comprises a multiplicity of outer micropores of average outer micropore diameter (D.sub.o) of 15-30 nm; dry thickness (T.sub.o) of 130-650 nm; and a micropore density (C.sub.o) of 500-3,000 micropores/m.sup.2. The ratio of D.sub.o to D.sub.i is greater than 1.1:1. A hydrophilic layer disposed on the outer aluminum oxide layer has a copolymer composed of (a) recurring units and (b) recurring units, wherein the (a) recurring units have an amide group, and the (b) recurring units have at least a phosphonic acid, a phosphoric acid, a salt of a phosphonic acid, or a salt of a phosphoric acid group.

A method for making a lithographic printing plate is disclosed including the steps of (i) image-wise exposing a printing plate precursor to heat and/or IR radiation; said precursor including a support and a coating comprising a polymerisable compound, an infrared absorbing compound, a borate compound and a photoinitiator including a trihaloalkyl group; (ii) developing the exposed precursor by treating the coating of the precursor with a gum solution thereby removing the coating from the support at the non-image areas; and/or by mounting the precursor on a plate cylinder of a lithographic printing press and rotating the plate cylinder while feeding dampening liquid and/or ink to the precursor.

A lithographic printing plate precursor is disclosed including a coating comprising a polymerisable compound, an infrared absorbing dye, a photoinitiator including a trihaloalkyl group and a borate compound.

Provided are a planographic printing plate precursor including a support and an image recording layer formed on the support, in which the image recording layer contains a polymer A which includes a constitutional unit A1 having an ethylenically unsaturated group, a weight-average molecular weight of the polymer A is in a range of 2,500 to 35,000, and a content of the constitutional unit A1 in the polymer A is 15 mol % or more, and a method of producing a planographic printing plate using the planographic printing plate precursor.