| 摘要 |
PURPOSE:To enhance the sensitivity of a printing master plate, to decrease the surface staining of a non-image part and to enhance preservable stability by using a specific sensitizing dye and specific binder resin. CONSTITUTION:A photoconductive insulating layer consisting essentially of an org. photoconductive compd., the sensitizing dye (A) and the binder resin (B) is formed on a conductive base body. The thiopyrylium salt compd. expressed by formula I is used as the dye A. In formula, Bu<t> denotes tert-butyl; R<1>, R<2> denote H, alkyl or 1-5C, etc.; R<3>, R<4> denote H, alkyl of 1-5C, etc.; Z<-> denotes anion. The comp. expressed by formula II, etc., are usable as the compd. expressed by such a formula. A high-polymer compd. which is soluble or disperses in an alkaline solvent (e.g.: copolymer contg. a monomer having a carboxylic acid group as a component) is used as the resin A. |
