| 摘要 |
PURPOSE: To obtain a lithographic printing plate in which ink can be efficiently repelled by setting the initial elastic modulus of a non-printing element part made of a hydrophilic swelled layer and increasing the initial elastic modulus of a printing element part to larger than that of the non-printing element part. CONSTITUTION: In a lithographic printing plate which can be formed of a photosensitive lithographic printing plate having high ink repellency using pure water as moistening water with a simple development, the initial elastic modulus of a non-printing element part made of a hydrophilic swelled layer is set to 0.01 to 10kgf/mm<2> , and the initial elastic modulus of a printing element part is set larger than that of the non-printing element. In this case, the water absorption rate of the swelled layer is set to a range of 10 to 2000%. An active light ray is emitted to the surface of the printing plate having the above swelled layer to generate a difference of the initial elastic moduluses of the printing element part and the non-printing element part, and the lithographic printing plate in which ink can efficiently repel is manufactured. |
