POSITIVE IMAGE PS PLATE AND CTCP LITHOGRAPHIC PRINTING PLATE PLATE MATERIAL

摘要

A positive image PS plate and CTcP lithographic printing plate plate material. The plate material comprises a hydrophilic support body, a bottom layer and a top layer, wherein the bottom layer and the top layer cover the hydrophilic support body and can be dissolved by an alkali after exposure. A bottom layer photosensitive composition comprises a chemical resistant functional resin, a photosensitive compound and a background coloring dye, wherein the chemical resistant functional resin has a molecular weight which is between 1000 - 100000, and a branch chain carbon atom thereof carries benzylsulfonyl amino and N-aryl maleimide repeating units. A top layer photosensitive composition consists of a film-forming resin, a photosensitive compound, a photoacid generator and a background coloring dye. The bottom layer and the top layer of the plate material are sensitive to visible light and ultraviolet light, and after having been exposed to visible light and/or ultraviolet light, and then subjected to a development treatment in an alkaline solution, the exposed area is dissolved and removed, and the unexposed area is not dissolved or slightly dissolved and corroded, and is preserved.