| 摘要 |
PURPOSE:To obtain a new waterless lithographic printing original plate at low cost by respectively providing an oleophilic coating film on one side of the outer surface of a layer having a foaming agent dispersed in the layer of a high polymeric material and a base sheet on the other surface. CONSTITUTION:The lithographic printing original plate 1 is constituted of respectively providing an oleophilic coating film 3 on one side of the outer surface of a layer 2 having a foaming agent dispersed in the layer of a high polymeric material and a base sheet 4 on the other surface. While transporting the original plate 1, the foaming agent dispersed layer 2 is selectively given the thermal energy of a thermal head heating body or the like through the oleophilic coating film 3, and the foaming agent dispersed layer 2 is locally exploded and heat decomposition-reacted to whereby form a foamed part. The printing plate obtained in this way is mounted on the plate drum in the form of the foamed part side to be a plate surface, and water ink is supplied onto the printing plate surface so as to allow water ink to selectively be stuck to the foamed part, and then printing paper is put into direct contact with the water ink-stuck printing plate for obtaining a printed matter. As a result, a lithographic printing original plate can easily be manufactured. Also, the inking system becomes simple. |
