PLATE MATERIAL FOR DIRECT PLANOGRAPHIC PRINTING PLATE FOR INK JET RECORDING METHOD

摘要

PROBLEM TO BE SOLVED: To obtain a planographic printing plate having good resolving power by forming an ink image on the ink absorbing layer provided on a plate material for planographic printing having a photosensitive layer by an ink jet recording system and subsequently exposing and developing the same. ;SOLUTION: An ink absorbing layer is provided on a planographic printing plate having a photosensitive layer and an ink image is formed thereon by ink jet recording and the ink absorbing layer is washed off with water to perform development to obtain a planographic printing plate. Polyvinyl alcohol is most pref. in the formation of the ink absorbing layer and particles such as silica is added to the ink absorbing layer to enhance ink absorbability and a compd. having a cationic group is added to the ink absorbing layer to enhance ink fixing properties. By adding a fluorine-containing polymeric compd. or a fluorine-containing surfactant to the ink absorbing layer, the spreading of ink is suppressed and absorbability is kept and a sharp image of high resolving power is obtained.;COPYRIGHT: (C)1998,JPO