| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a positive lithographic printing original plate for an IR laser, in which direct platemaking by scanning exposure based on digital signals can be carried out, excellent chemical resistance and alkali developer resistance are obtained, resistance against an alkali developer solution is rapidly eliminated by exposure, and thereby preferable development latitude is obtained. <P>SOLUTION: The lithographic printing original plate comprises an anodized aluminum support having an Si atom deposition amount of 0.5 to 8 mg/m<SP>2</SP>. On the aluminum support, a layer which contains an alkali-soluble resin having at least one kind selected from structural units having a sulfonamide group in a side chain and a layer which contains a water-insoluble and alkali-soluble resin and an IR ray absorbent, and in which solubility with an alkali aqueous solution is increased by exposure, are successively disposed in this order. <P>COPYRIGHT: (C)2010,JPO&INPIT |
