| 摘要 |
PURPOSE:To enhance image density and to prevent develope stain occurring in dry development by incorporating a vinyl chloride-acrylic and ester copolymer specified in compsn. and silica fine particle in a precoat layer. CONSTITUTION:A precoat layer and a photosensitive layer composed essentially of a diazo compd. and a coupling component are formed on a support to form a diazo copying material. Said precoat layer contains a vinyl chloride-acrylic acid ester (VC-ACE) copolymer and fine silica powder, and in said copolymer ACE is contained by 20-70wt% in terms of monomer unit. Such a compsn. is dissolved in water for example, and support is coated with this solution and dried to form an precoat layer. The photosensitive layer is formed on it. The use of such a precoat layer readily allows the silica particles to rise to the surface due to the mutual action of the VC-ACE copolymer and the silica particles, permits a high density image to be formed, and prevents developing statins in the dry development. |
