Lithographic printing plate precursor, lithographic printing method and packaged body of lithographic printing plate precursors

Abstract

(1) A packaged body of lithographic printing plate precursors, wherein an image-recording layer or a protective layer of the outermost surface layer contains an inorganic layered compound. (2) A lithographic printing plate precursor having a protective layer containing an inorganic layered compound, and an image-recording layer containing a binder polymer. (3) A lithographic printing plate precursor having a protective layer containing an inorganic layered compound, and an image-recording layer containing an infrared absorber and an iodonium compound.

1 . A lithographic printing plate precursor comprising:
 a support;   an image-recording layer comprising (A) an actinic ray absorber, (B) a polymerization initiator and (D) a binder polymer, and the image-recording layer is capable of being removed by at least one of a printing ink and a fountain solution; and   a protective layer comprising an inorganic layered compound, in this order, wherein the binder polymer has an ethylene oxide group.   
     
     
         2 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the inorganic layered compound has an aspect ratio of 10 or more.   
     
     
         3 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the binder polymer has from 2 to 120 repeating units comprising an ethylene oxide group.   
     
     
         4 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the binder polymer has from 6 to 60 repeating units comprising an ethylene oxide group.   
     
     
         5 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the binder polymer is water-insoluble.   
     
     
         6 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the image-recording layer comprises discontinuous particles.   
     
     
         7 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the binder polymer is polymer particles dispersed in the image-recording layer.   
     
     
         8 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the image-recording layer comprises at least one of microcapsules and microgels.   
     
     
         9 . The lithographic printing plate precursor according to  claim 1 ,
 wherein the protective layer has a mass of from 0.02 to 1 g/m 2 .   
     
     
         10 . A lithographic printing method comprising:
 imagewise exposing a lithographic printing plate precursor according to  claim 1  by irradiation with an actinic ray;   removing an area not irradiated with an actinic ray of the image-recording layer by feeding at least one of a printing ink and a fountain solution; and   performing printing.   
     
     
         11 . A lithographic printing plate precursor comprising:
 a support;   an image-recording layer capable of imaging by an infrared laser exposure; and   a protective layer, in this order,   wherein the lithographic printing plate precursor is capable of printing by being mounted on a printing press without a development process after an image recording or by an image recording after being mounted on a printing press, and   wherein the image-recording layer comprises (E) an infrared absorber and (F) an iodonium salt and does not substantially comprise a compound other than an infrared absorber (E) which changes a color of the compound by interacting with at least one of an acid, a base and a radical, and the protective layer comprises an inorganic layered compound.   
     
     
         12 . The lithographic printing plate precursor according to  claim 11 ,
 wherein an absorbance at any wavelength of from 400 to 700 nm of an infrared absorber (E) in an exposed area changes by at least 0.05 or more by an infrared laser exposure as compared with an absorbance of an infrared absorber (E) in an unexposed area.   
     
     
         13 . The lithographic printing plate precursor according to  claim 11 ,
 wherein an absorbance at any wavelength of from 400 to 700 nm of an infrared absorber (E) in an exposed area becomes greater by at least 0.05 or more by an infrared laser exposure as compared with an absorbance of an infrared absorber (E) in an unexposed area.   
     
     
         14 . The lithographic printing plate precursor according to  claim 11 ,
 wherein the infrared absorber (E) is a compound represented by formula (D1)   
       
         
           
           
               
               
           
         
         wherein R 1  and R 2  each independently represents a hydrogen atom or a hydrocarbon group having from 1 to 12 carbon atoms, and R 1  and R 2  may be bonded to each other to form a cyclic structure; Ar 1  and Ar 2  each independently represents an aromatic hydrocarbon group which may have a substituent; Y 1  and Y 2  each independently represents a sulfur atom or a dialkylmethylene group having 12 or less carbon atoms; R 3  and R 4  each independently represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent; R 5 , R 6 , R 7  and R 8  each independently represents a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms; R 9  and R 10  each independently represents an aromatic hydrocarbon group having from 6 to 10 carbon atoms which may have a substituent, an alkyl group having from 1 to 8 carbon atoms or a hydrogen atom, and R 9  and R 10  may be bonded to each other to form a cyclic structure, and in this case, the cyclic structure may arbitrarily contain one or more hetero atoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom; and X −  represents a counter anion, provided that when any of R 1  to R 8  is substituted with a sulfo group, X −  is not necessary. 
       
     
     
         15 . The lithographic printing plate precursor according to  claim 11 ,
 wherein the image recording layer further comprises a sulfonium salt.   
     
     
         16 . The lithographic printing plate precursor according to  claim 11 ,
 wherein the image recording layer comprises at least one of microcapsules and microgels.   
     
     
         17 . A lithographic printing method comprising:
 imagewise exposing a lithographic printing plate precursor according to  claim 11  with an infrared laser;   removing an unexposed area of an image-recording layer in a state of fitting the lithographic printing plate precursor to a cylinder of a printing press, so as to form a lithographic printing plate; and   performing printing with the lithographic printing plate.