| 摘要 |
PROBLEM TO BE SOLVED: To improve print wear, printing-out properties in makeup process and plate check feasibility by adding white pigment at least, to one of printing plate-constituent layers in lithographic plate with a hydrophilic swelling layer formed on a base plate. SOLUTION: This photosensitive lithographic plate has characteristics such as simple development treatment, high ink repellency without the necessity of treatment for desensitization, a wide range of control of wetting water and the adaptability of pure water as wetting water. In addition, this lithographic plate is composed, at least, of a base plate a primer layer and a hydrophilic swelling layer formed sequentially, and contains white pigment in the primer layer adjacent to the hydrophilic swelling layer, or contains white pigment in the base plate adjacent to the hydrophilic swelling layer. In this case, the moisture absorbing amount of a nonimage linear part consisting of the hydrophilic swelling layer is set to 1-50g/m<2> and the water swelling coefficient is set to the range of 10-2000%. Further, the hydrophilic swelling layer is subjected to three-dimensional crosslinking reaction by the reactive functional group of hydrophilic polymer. In addition, the hydrophilic swelling layer is formed in a laminar process on the base plate by making it insoluble in water. |
