POSITIVE PHOTOSENSITIVE COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide a positive photosensitive composition excellent in image contrast and having superior development latitude. SOLUTION: The positive photosensitive composition has a recording layer containing a polymer soluble in an alkaline developing solution, a dihydropyridine compound and a cyanine dye on a substrate surface-treated with an acid-base associated body salt. When the composition is used, a printing plate material of the composition excellent in contrast, having a sufficient residual film rate in the printing area and no residual film in the non-printing area and excellent in processing stability in development can be provided.