| 摘要 |
PROBLEM TO BE SOLVED: To improve the ink deposition property of image parts and to obtain an excellent ink repulsive property by laminating a photosensitive layer and hydrophilic swelling layer in this order on a substrate, thereby forming an original plate. SOLUTION: The original plate is formed by laminating the photosensitive layer and hydrophilic swelling layer in this order on the substrate. The original plate may be provided with a protective layer on this hydrophilic swelling layer. The photosensitive layer is a photosetting photosensitive layer including a photosetting compd. The photosetting compd. means a compd. contg. a functional group which is changed in polymn., crosslinking, etc., by irradiation with active rays. The hydrophilic swelling layer has a phase sepn. structure composed of two phases; a phase consisting essentially of a hydrophilic polymer and a phase consisting essentially of a hydrophobic polymer. The hydrophilic polymer is a polymer which is substantially insoluble in water and exhibits a water swelling property. Namely, the hydrophilic polymer means a polymer which adsorbs or absorbs water under ordinary use conditions and means a polymer which dissolves in water or swells in water. The hydrophobic polymer mainly composed of an aq. emulsion is preferably used. |
