Abstract: Provided are: an on-press development type planographic printing plate precursor having a support, an image-recording layer, and an overcoat layer in this order, in which a content of an inorganic compound in the overcoat layer is zero or is more than 0% by mass or less than 1% by mass with respect to a total mass of the overcoat layer, and the image-recording layer contains an infrared absorber, a polymerization initiator, a polymerizable compound, and an oil agent; and a method of preparing a planographic printing plate and a planographic printing method in which the on-press development type planographic printing plate precursor is used.

Abstract: Provided is 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 image-recording layer contains an infrared absorber, an electron-donating polymerization initiator, and a polymerizable compound, HOMO of the infrared absorber - HOMO of the electron-donating polymerization initiator is 0.60 eV or less, and the outermost layer contains a discoloring compound. 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.

Abstract: Provided is 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 image-recording layer contains an infrared absorber, an electron-accepting polymerization initiator, and a polymerizable compound, LUMO of the electron-accepting polymerization initiator-LUMO of the infrared absorber is 0.45 eV or more, and the outermost layer contains a discoloring compound. Also provided is 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.

Abstract: Provided is a lithographic printing plate precursor having a support, an image-recording layer, and an overcoat layer in this order, in which the image-recording layer contains a polymerization initiator, a polymerizable compound, and particles, and the overcoat layer contains a discoloring compound. Also provided is a method of preparing a lithographic printing plate or a lithographic printing method that uses the lithographic printing plate precursor.

Abstract: A lithographic printing plate precursor has 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. A method for producing a lithographic printing plate includes image-exposing the lithographic printing plate precursor using an infrared laser.

Abstract: A curable composition includes a salt compound having a) an organic anion in which, in Hansen solubility parameter, ?d is 16 or more, ?p is 16 or more and 32 or less, and ?H is 60% or less of ?p 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.

Abstract: Provided is an on-press development type lithographic printing plate precursor having an aluminum support and an image-recording layer on the aluminum support, in which the image-recording layer contains an infrared-absorbing polymethine colorant having HOMO of ?5.2 eV or less, a polymerization initiator, and a polymerizable compound having 7 or more functional groups and contains or does not contain a polymer having a molecular weight 10,000 or more, and in a case where the image-recording layer contains the polymer having a molecular weight of 10,000 or more, a ratio Wp/Wm of a content Wp of the polymer having a molecular weight of 10,000 or more to a content Wm of the polymerizable compound having 7 or more functional groups is 1.00 or less. Also provided are a method for preparing a lithographic printing plate and a lithographic printing method using the lithographic printing plate precursor.

Abstract: A lithographic printing plate precursor including an image recording layer on a hydrophilic support, in which the image recording layer includes a polymerization initiator, an infrared absorbent, a polymerizable compound, and an acid color former, and the infrared absorbent includes a compound represented by Formula 1, as well as a method of preparing a lithographic printing plate by use of the lithographic printing plate precursor.

Abstract: A color developing composition containing a compound represented by the Formula (1) as defined herein, a lithographic printing plate precursor including a support and an image-recording layer containing the color developing composition, a method for producing a lithographic printing plate including: exposing the lithographic printing plate precursor in an image pattern; and removing a non-exposed portion in the image-recording layer using at least one of printing ink or dampening water on a printer, and a color developing compound represented by the Formula (1) as defined herein.

Abstract: 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 having a constituent unit derived from a monomer having a solubility parameter of 20 MPa1/2 or more, an infrared absorber, and a polymer particle; a resin composition for producing a lithographic printing plate precursor including the polymer, an infrared absorber, and a polymer particle; and a method for producing a lithographic printing plate in which the lithographic printing plate precursor is used.

Abstract: 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.

Abstract: A lithographic printing plate precursor including an image recording layer on a hydrophilic support, in which the image recording layer includes a polymerization initiator, an infrared absorbent, a polymerizable compound, and an acid color former, and the infrared absorbent includes a compound represented by Formula 1, as well as a method of preparing a lithographic printing plate by use of the lithographic printing plate precursor. In Formula 1, at least one of Ar1 or Ar2 has a group represented by the following Formula 2. —X??Formula 2 X represents a halogen atom, —C(?O)—X2—R11, —C(?O)—NR12R13, —O—C(?O)—R14, —CN, —SO2N15R16, or a perfluoroalkyl group, X2 represents a single bond or an oxygen atom, R11 and R14 each independently represent an alkyl group or an aryl group, and R12, R13, R15 and R16 each independently represent a hydrogen atom, an alkyl group, or an aryl group.

Abstract: Provided are a curable composition including a sail compound having a) an organic anion in which, in Hansen, solubility parameter, ?d is 16 or more, ?p is 16 or more and 32 or less, and ?H is 60% or less of ?p 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.

Abstract: A color developing composition which develops colors in a high density and does not significantly discolor when aged, a lithographic printing plate precursor which has excellent plate-inspecting properties by means of color development and is capable of maintaining strong color development even when aged after color development, a plate making method for a lithographic printing plate in which the lithographic printing plate precursor is used, and a new compound that can be preferably used as a color developer. The color developing composition of the present invention includes a compound represented by Formula 1. The compound in the present invention is represented by Formula 1. In Formula 1, R1 represents a group in which an R1—O bond is cleaved by heat or exposure to infrared rays.

Abstract: A color developing composition containing a compound represented by the Formula (1) as defined herein, a lithographic printing plate precursor including a support and an image-recording layer containing the color developing composition, a method for producing a lithographic printing plate including: exposing the lithographic printing plate precursor in an image pattern; and removing a non-exposed portion in the image-recording layer using at least one of printing ink or dampening water on a printer, and a color developing compound represented by the Formula (1) as defined herein.

Abstract: An object of the present invention is to provide a color developing composition which develops colors in a high density and does not significantly discolor when aged, a lithographic printing plate precursor which has excellent plate-inspecting properties by means of color development and is capable of maintaining strong color development even when aged after color development, a plate making method for a lithographic printing plate in which the lithographic printing plate precursor is used, and a new compound that can be preferably used as a color developer. The color developing composition of the present invention includes a compound represented by Formula 1. The compound in the present invention is represented by Formula 1. In Formula 1, R1 represents a group in which an R1—O bond is cleaved by heat or exposure to infrared rays.