| 摘要 |
PURPOSE:To enhance image density and to prevent stains due to dry development by incorporating at least one kind of vinyl chloride-acrylate copolymers having a specified proper carbon number or more in each alkyl group of the ester parts in a precoat layer. CONSTITUTION:It is essential to use the vinyl chloride-alkyl acrylate copolymer having >=4 carbon number of each alkyl group for the precoat layer. A preferable carbon number of said alkyl group is 4-20. If the carbon number is <=4, stains due to dry development process cannot be sufficiently prevented. As said alkyl ester, butyl ester, etc., are enumerated, and fine porous inorg. or org. fillers, such as fine silica particles, are, preferably, added in combination for the precoat layer. Other resins and other third and fourth components may be added so long as this purpose is not hindered. |
