| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a photosensitive lithographic printing plate original plate for an infrared laser that is superior in the balance of developability and scratch resistance, and to provide a method for making a lithographic printing plate using the original plate, in which proper development is performed with an alkaline developer, without having to use an organic solvent which presents hazards to human bodies and environment, and with which superior images can be formed. <P>SOLUTION: The photosensitive lithographic printing plate original plate for an infrared laser has a lower layer containing (A-1) a high-molecular compound and (B) an an infrared absorbent and an upper layer containing (A-2) a high-molecular compound different from the high-molecular compound contained in the lower layer on a support having a hydrophilic surface, wherein the rate of dissolution of the upper layer in an alkaline aqueous solution is ≥1.5 nm/s. By using such a plate material, a lithographic printing plate of high image quality can be obtained, by imagewise exposure using an infrared laser and development with an alkaline aqueous solution of ≥pH 12, having an organic solvent content of ≤0.5 mass%. <P>COPYRIGHT: (C)2007,JPO&INPIT |
