| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithographic printing plate precursor which allows good removal of a pigment in a non-image area after development, whereby residual color in the non-image area is eliminated to enhance plate inspectability and staining in printing can also be prevented, and a method for preparation of a lithographic printing plate using the same. <P>SOLUTION: The lithographic printing plate precursor is obtained by disposing a photosensitive layer comprising a binder polymer having an acid value of ≤0.3 meq/g on an aluminum support having a hydrophilic surface, wherein the photosensitive layer comprises a pigment dispersed with a pigment dispersant which is free from a -COOH group, a -PO<SB>3</SB>H<SB>2</SB>group and a -OPO<SB>3</SB>H<SB>2</SB>group. The method for preparation of a lithographic printing plate comprises: exposing the lithographic printing plate precursor with a laser beam having an oscillation wavelength in a wavelength region of 360-450 nm; and rubbing a surface of the exposed lithographic printing plate precursor with a rubbing member in a presence of a developer having pH of 2-10 in an automatic processor equipped with the rubbing member to remove a protective layer and a non- exposed area of the photosensitive layer. <P>COPYRIGHT: (C)2008,JPO&INPIT |
