Processing method of lithographic printing plate preursor

Abstract

A processing method of a lithographic printing plate precursor includes: exposing imagewise a lithographic printing plate precursor comprising a support on a surface of which at least one of: a hydrophilizing treatment; and an undercoat layer has been provided and an image-recording layer, to cure an exposed area of the image-recording layer; and undergoing developing processing with an aqueous solution having pH of from 2 to 10, wherein the aqueous solution comprises an amphoteric surfactant and an anionic surfactant selected from an anionic surfactant having an aliphatic chain and a total number of carbon atoms included in the aliphatic chain of 6 or more and an anionic surfactant having an aromatic ring and a total number of carbon atoms of 12 or more, and a content of the anionic surfactant is from 0.1 to 3.3% by weight of the aqueous solution.

1 . A processing method of a lithographic printing plate precursor comprising:
 exposing imagewise a lithographic printing plate precursor comprising a support on a surface of which at least one of: a hydrophilizing treatment; and an undercoat layer has been provided and an image-recording layer, to cure an exposed area of the image-recording layer; and   undergoing developing processing with an aqueous solution having pH of from 2 to 10,   wherein the aqueous solution comprises an amphoteric surfactant and an anionic surfactant selected from an anionic surfactant having an aliphatic chain and a total number of carbon atoms included in the aliphatic chain of 6 or more and an anionic surfactant having an aromatic ring and a total number of carbon atoms of 12 or more, and a content of the anionic surfactant is from 0.1 to 3.3% by weight of the aqueous solution, and   wherein the image-recording layer comprises a binder polymer, a polymerizable compound and a polymerization initiator.   
     
     
         2 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein the undercoat layer comprises an acid group or a salt of an acid. 
     
     
         3 . The processing method of a lithographic printing plate precursor as claimed in  claim 2 , wherein the acid group is a sulfonic acid group. 
     
     
         4 . The processing method of a lithographic printing plate precursor as claimed in  claim 3 , wherein the binder polymer comprises an onium group. 
     
     
         5 . The processing method of a lithographic printing plate precursor as claimed in  claim 4 , wherein the binder polymer comprises an ammonium group in a side chain. 
     
     
         6 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein an oil-desensitizing treatment is carried out simultaneously with the development processing. 
     
     
         7 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein a content of the anionic surfactant is from 0.3 to 3% by weight of the aqueous solution. 
     
     
         8 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein a content of the anionic surfactant is from 0.5 to 1.5% by weight of the aqueous solution. 
     
     
         9 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein the polymerizable compound is an addition-polymerizable compound having at least one ethylenically unsaturated double bond. 
     
     
         10 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein the amphoteric surfactant is a compound represented by formula <2> 
       
         
           
           
               
               
           
         
         wherein R18, R19 and R20 each represents a hydrogen atom or an alkyl group, provided that all of R18, R19 and R20 are not hydrogen atoms at the same time. 
       
     
     
         11 . The processing method of a lithographic printing plate precursor as claimed in  claim 1 , wherein the aqueous solution has a pH of from 3 to 7.