| 摘要 |
PURPOSE:To simply obtain a lithographic plate with an output signal from a computer or the like, that is, a thermal or optical mode by forming an image forming layer composed chiefly of 2 kinds of specified tetrazolium salt (co)polymers and a photoreducing agent or a thermal reducing agent on a hydrophilic support. CONSTITUTION:An image forming layer contg. tetrazolium salt homopolymers represented by formulaeI, II (where each of R1 and R2 is H, CH3, NO2, OH or COOH, X is Cl or Br, and n is 10-5,000) or tetrazolium salt copolymers each contg. other copolymerizable monomer such as acrylic acid, styrene or acrylamide and a photoreducing agent such as disulfide which forms a reducing agent in the presence of light or a thermal reducing agent such as polyphenol is formed on a hydrophilic support such as an Al plate provided with a hydrophilic property. The image forming layer is exposed through an original, or heat is imagewise applied to the layer by means of a thermal head. The exposed part or the heat applied part is made insoluble. By immersing the layer in water, the unexposed part or the unheated part is dissolved and removed to manufacture a lithographic plate having superior printing resistance and giving clear prints. |
