| 摘要 |
PROBLEM TO BE SOLVED: To simplify a process step and to omit a special surface treatment of a substrate necessary to give ink-repelling property to the plate, by providing a photosensitive hydrophilic swelling layer having a phase separation structure composed of a specified material group. SOLUTION: The photosensitive hydrophilic swelling layer of this photosensitive planographic printing master plate has a phase separation structure of at least two phases of a phase essentially composed of a hydrophilic polymer and a phase essentially composed of a hydrophobic polymer. The hydrophilic polymer and/or the hydrophobic polymer have ethylenicaly unsatd. groups. As for the hydrophilic polymer, carboxylate copolymers are preferably used, and especially, copolymers of vinyl esters and methacrylic acid or acrylic ester are preferable. As for the hydrophobic polymer, polymers essentially composed of water-emulsion are preferably used, and for example, polyvinylic latex and conjugate diene polymer latex are used. |
