| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of preparing a lithographic printing plate which includes a simple, one-solution and one-step process, which does not require a water washing step, exhibits good developing property without leaving residues of a photosensitive layer in a non-image area and allows the lithographic printing plate to have good printing durability and excellent stainproof property in the non-image area. <P>SOLUTION: The method of preparing the lithographic printing plate includes the steps of: subjecting a lithographic printing plate precursor, which has the photosensitive layer comprising (A) a polymerization initiator, (B) a polymerizable compound, (C) a sensitizing dye and (D) a binder polymer and a protective layer in this order on a hydrophilic support, to laser exposure; and rubbing the surface of the laser-exposed lithographic printing plate precursor with a rubbing member in the presence of a developer, which contains a water-soluble polymer compound and has the pH of 2-11, to remove the protective layer and an unexposed area of the photosensitive layer. The water-soluble polymer compound is a vinyl copolymer having: a monomer unit having at least one functional group interacting with the surface of the support; and another monomer unit having at least one hydrophilic group which is different from the functional group interacting with the surface of the support. <P>COPYRIGHT: (C)2011,JPO&INPIT |
