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 μm to 20 μm; 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.

A lithographic printing plate precursor includes a photopolymerizable coating and an overcoat which is deactivated after imagewise exposure and preheating of the precursor.

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 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 top layer provided above the photopolymerisable layer; characterized in that the top layer includes a non-polymeric polyfunctional compound in an amount between 2 mg/m.sup.2 and 80 mg/m.sup.2 which comprises at least two carboxyl and/or carboxylate groups.

The present disclosure provides an on-press development type lithographic printing plate precursor having a support, an image-recording layer, and an outermost layer in this order, in which a contact angle of a water droplet on a surface of the outermost layer that is measured 2 seconds after the water droplet is landed by an airborne water droplet method is greater than 36°. The present disclosure also provides applications of the on-press development type lithographic printing plate precursor.

IR-sensitive lithographic printing plate precursors provide a stable print-out image using a unique IR radiation-sensitive composition in an infrared radiation-sensitive image-recording layer. This IR radiation-sensitive composition includes: (1) a free radical initiator composition that comprises an electron-donating agent; (2) a free radically polymerizable composition; and (3) a color-changing compound that is represented by the Structure (I) having an indene ring in the conjugated chain between the aromatic terminal groups. The compound can also have a —C(═O)—OR.sup.7, —SO.sub.2—R.sup.3, or —SO.sub.2NR.sup.8R.sup.9 group wherein R.sup.7 represents a substituted or unsubstituted alkyl group having a secondary or tertiary connecting carbon that connects to the rest of the —C(═O)—OR.sup.7 group; and R.sup.8, R.sup.9, and R.sup.10 independently represent substituted or unsubstituted alkyl, aryl, or heteroaryl groups. After IR imaging, these precursors exhibit desirable printout images both fresh and after dark storage. The precursors can be developed off-press or on-press.

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.

The present invention relates to a printing plate including a first silicone layer and a second silicone layer which have different ink acceptabilities on a support. An object of the present invention is to provide a printing plate that dispenses with a development step and that has excellent image reproducibility, ink repellency, ink acceptability, and printing durability.

The present disclosure provides an on-press development type lithographic printing plate precursor having a support, an image-recording layer, and an outermost layer in this order, in which the outermost layer contains a hydrophobic polymer, and a contact angle of a water droplet on a surface of the outermost layer that is measured 2 seconds after the water droplet is landed by an airborne water droplet method is less than 36°. The present disclosure also provides applications of the on-press development type lithographic printing plate precursor.