Developing solution for photosensitive lithographic printing plate, plate-making method of lithographic printing plate, and photosensitive lithographic printing plate

Abstract

A plate-making method of a lithographic printing plate is disclosed, which comprises the steps of exposure of a photosensitive lithographic printing plate having the acid value of a photosensitive layer of 1.0 meq/g or less with a laser beam, and then development with a developing solution having a pH value of 13.0 or less at a developing speed in an unexposed domain of 0.05 μm/s or more and at an osmotic speed of a developing solution in an exposed domain of 0.1 μm/s or less.

What is claimed is:  
     
         1 . A plate-making method of a lithographic printing plate which comprises the steps of exposure of a photosensitive lithographic printing plate having the acid value of a photosensitive layer of 1.0 meq/g or less with a laser beam, and then development with a developing solution having a pH value of 13.0 or less at a developing speed in an unexposed domain of 0.05 μm/s or more and at an osmotic speed of a developing solution in an exposed domain of 0.1 μm/s or less.  
     
     
         2 . A plate-making method of a lithographic printing plate which comprises the steps of exposure of a photosensitive lithographic printing plate having the acid value of a photosensitive layer of 1.0 meq/g or less with a laser beam, and then development with a developing solution having a pH value of 13.0 or less so as to dissolve the photosensitive layer in order from the surface without swelling and peeling of the photosensitive layer.  
     
     
         3 . A developing solution for a photosensitive lithographic printing plate which is a non-silicate-based developing solution and contains an inorganic alkali agent and a nonionic compound represented by the following formula (I):  
       A-W  (I)  
       wherein A represents a hydrophobic organic group having 1.5 or more of logP of A-H, and W represents a hydrophilic organic group having less than 1.0 of logP of W-H.  
     
     
         4 . The developing solution for a photosensitive lithographic printing plate as claimed in  claim 3 , which contains a chelating agent to a divalent metal.  
     
     
         5 . The developing solution for a photosensitive lithographic printing plate as claimed in  claim 3 , which has a pH of from 10.0 to 12.5 and electrical conductance of from 3 to 30 mS/cm.  
     
     
         6 . The developing solution for a photosensitive lithographic printing plate as claimed in  claim 3 , which contains a carbonic acid or a carbonate.  
     
     
         7 . The plate-making method of a lithographic printing plate as claimed in  claim 1 , wherein the photosensitive lithographic printing plate is a photopolymerizable lithographic printing plate having on a support a photopolymerizable photosensitive layer containing the following i) and ii) as essential components: 
 i) a compound having an addition polymerizable ethylenically unsaturated bond,    ii) a photopolymerization initiator.    
     
     
         8 . The plate-making method of a lithographic printing plate as claimed in  claim 2 , wherein the photosensitive lithographic printing plate is a photopolymerizable lithographic printing plate having on a support a photopolymerizable photosensitive layer containing the following i) and ii) as essential components: 
 i) a compound having an addition polymerizable ethylenically unsaturated bond,    ii) a photopolymerization initiator.    
     
     
         9 . The plate-making method of a lithographic printing plate as claimed in  claim 7 , wherein the photopolymerizable photosensitive layer contains a titanocene-based initiator or a colorant such as a pigment.  
     
     
         10 . The plate-making method of a lithographic printing plate as claimed in  claim 8 , wherein the photopolymerizable photosensitive layer contains a titanocene-based initiator or a colorant such as a pigment.  
     
     
         11 . The plate-making method of a lithographic printing plate as claimed in  claim 7 , wherein the support is an anodized aluminum support containing an organic compound having a phosphorus-containing atomic group on the surface of the support.  
     
     
         12 . The plate-making method of a lithographic printing plate as claimed in  claim 8 , wherein the support is an anodized aluminum support containing an organic compound having a phosphorus-containing atomic group on the surface of the support.  
     
     
         13 . A photosensitive lithographic printing plate comprising a photopolymerizable photosensitive layer, wherein the photosensitive layer contains a compound having an acid radical having a pKa of 9 or less and the acid value of the photosensitive layer is from 0.20 to 0.60 meq/g.  
     
     
         14 . A plate-making method of a lithographic printing plate which comprises the steps of exposure of a photosensitive lithographic printing plate comprising a support having an anodized film on the surface having provided thereon a photopolymerizable photosensitive layer containing a compound having an addition polymerizable ethylenically unsaturated double bond, a high polymer soluble or swelling in an alkali aqueous solution, and a photopolymerization initiator with a laser beam, and then development with a developing solution comprising an alkali aqueous solution containing at least one of a nonionic aromatic ether-based activator represented by the following formula (I-A) and a nonionic aromatic ether-based activator represented by the following formula (I-B):  
       
         
           
           
               
               
           
         
       
       wherein R 1  and R 2  each represents H or an alkyl group having from 1 to 100 carbon atoms, and n and m each represents an integer of from 0 to 100.  
     
     
         15 . A plate-making method of a lithographic printing ate which comprises the steps of image exposure of a photosensitive lithographic printing plate comprising an aluminum support having provided thereon a photopolymerizable photosensitive layer containing a compound having an ethylenically unsaturated double bond, a photopolymerization initiator and a high polymer binder, and then development with a developing solution containing an inorganic alkali agent and a nonionic surfactant having a polyoxyalkylene ether group, having a pH of from 10.0 to 12.5, and an electrical conductance of from 3 to 30 mS/cm.