The invention relates to a coating material for coating a metal or non-metal printing plate, comprising a liquid starting material which can be polymerised using UV light in order to form a polymer matrix, and comprising a filling material which can be covalently incorporated into a polymer matrix of the starting material. The filling material is of a sub-microscale size, wherein absorption of IR radiation can be brought about by the filling material in the starting material, said absorption being higher than an absorption without filling material. The invention also relates to a printing plate comprising a cylindrical main body, wherein a polymer layer is applied to at least parts of a circumferential surface of the main body, with the polymerisation thereof being induced by UV light, wherein the polymer layer has a sub-microscale filling material, and wherein a higher absorption of infrared radiation is brought about using the filling material in the polymer layer than in the polymer layer without filling material.

Provided is an on-press development type lithographic printing plate precursor having two or more maximal absorption wavelengths in a wavelength range of 760 nm to 900 nm, in which in a case where the on-press development type lithographic printing plate precursor is subjected to exposure to infrared having a wavelength of 830 nm at an energy density of 110 mJ/cm.sup.2, in a portion subjected to the exposure, a brightness change ΔL before the exposure and after storage subsequent to the exposure for 24 hours under conditions of 25° C. and 70% RH is 3.0 or more. Also provided are a method of preparing a lithographic printing plate and a lithographic printing method in which the on-press development type lithographic printing plate precursor is used.

The blanket cylinder of a printing press is used to remove oleophobic debris from an imaged dry printing member. Following imaging—e.g., imagewise exposure of the printing member to radiation that ablates the layer below the oleophobic layer, or de-anchors it from the oleophobic layer without ablation—the printing member is brought into rolling contact with the blanket cylinder, and the press is operated “on impression.” This rolling contact may remove not only the oleophobic top layer but ablation debris of the underlying imaging layer as well.

A positive-working lithographic printing plate precursor is disclosed which comprises on a support having a hydrophilic surface or which is provided with a hydrophilic layer a heat and/or light-sensitive coating including an infrared absorbing agent, said heat and/or light-sensitive coating comprising a first layer comprising a binder including a monomeric unit including a sulfonamide group; characterized in that the binder further comprises a monomeric unit including a phosphonic acid group or a salt thereof, and that the monomeric unit comprising the phosphonic acid group is present in an amount comprised between 2 mol % and 15 mol %.

An object of the invention is to provide a water-based lithographic printing method that is excellent in printing quality and environmental aspects. The invention concerns a method of producing a printed material, including the steps of: allowing a water-based ink to adhere to a surface of a heat sensitive layer of a lithographic printing plate having a surface on which an ink repelling layer and the heat sensitive layer exist; and transferring the adhering water-based ink directly or via a blanket to a printing substrate.

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 is a lithographic printing plate precursor having an aluminum support and an image-recording layer formed on the aluminum support, in which the image-recording layer contains resin particles A that have an ethylenically unsaturated group and a compound B that has an ethylenically unsaturated group other than the resin particles A and has an ethylenically unsaturated bond valence of 1.5 mmol/g or more. Also provided are a method for preparing lithographic printing plate or a lithographic printing method using the lithographic printing plate precursor.

Provided is an on-press development type lithographic printing plate precursor including an aluminum support and an image-recording layer on the aluminum support, in which the image-recording layer contains an infrared absorber, a polymerization initiator, a polymerizable compound, and an addition polymerization-type resin having a hydrophilic structure, a water contact angle on a surface of the aluminum support on a side of the image-recording layer that is determined by an airborne water droplet method is 110° or less, and the polymerizable compound includes a polymerizable compound having 7 or more functional groups. Also provided are a method for preparing a lithographic printing plate and a lithographic printing method using the lithographic printing plate precursor.

A lithographic printing plate precursor is disclosed including on a support a coating comprising (i) a photopolymerisable layer including a polymerisable compound, a first infrared absorbing dye including at least one electron withdrawing substituent and a photoinitiator; and (ii) a top layer provided above the photopolymerisable layer which includes a second 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.

A curable composition includes a salt compound having a) an organic anion in which, in Hansen solubility parameter, δd is 16 or more, δp is 16 or more and 32 or less, and δH is 60% or less of δp and b) a counter cation. A lithographic printing plate precursor having an image-recording layer containing the curable composition, a method for producing a lithographic printing plate using the lithographic printing plate precursor, and a compound that is used in the image-recording layer in the lithographic printing plate precursor are also set out.