| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a negative planographic printing original plate which has high stability with time free from staining in a non-image area or from an image defect at the time of printing by image exposure and development even after the plate is stored under high humidity conditions after manufactured, and more preferably, which is writable with IR laser light, which has high sensitivity and high stability with time free from staining in a non-image area or from an image defect. <P>SOLUTION: The planographic printing original plate has at least one layer of photosensitive layer containing a polymerization initiator, a polymerizable compound and a binder polymer on an aluminum supporting body. The photosensitive layer has a halogen ion concentration in a range of from 0 to 4×10<SP>-5</SP>mol/m<SP>2</SP>. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
