| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polymerizable composition which excels in plate wear and image formability and is suitable for drawing by laser light and a lithographic printing master plate. <P>SOLUTION: The polymerizable composition contains a binder polymer having the repeating unit expressed by a general formula (I), an IR absorbent, a polymerization initiator and a polymerizable compound. The lithographic printing master plate is characterized by having a photosensitive layer composed of the polymerizable composition on a support. In the general formula (I), R<SP>1</SP>represents a hydrogen atom or methyl group: R<SP>2</SP>represents a linkage group; A represents an oxygen atom or -NR<SP>3</SP>-; R<SP>3</SP>represents a hydrogen atom or 1-10C univalent hydrocarbon group; n represents an integer from 1 to 5. The lithographic printing master plate has the photosensitive layer which contains the binder polymer, the IR absorbent, the polymerization initiator and the polymerizable compound on the support, in which the developing speed of an unexposed portion with respect to an alkaline developing solution of a pH 10 to 13.5 is ≥80 nm/sec and the permeation rate in the exposed portion of the alkaline developing solution is ≤100 nF/sec. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
