| 摘要 |
PURPOSE:To obtain a diazo photosensitive paper forming a sharp image superior in image quality, such as image density and contrast, by adding a urea formaldehyde resin as a filler to a precoat layer. CONSTITUTION:A formaldehyde resin having 5-6mum particle diameter and 2.7- 3.0cm<3>/g pore volume, as a filler is dispersed together with binder and dye into water, and 5-10wt% acid is added to adjust pH of the dispersion and make it serviceable as a precoat. A paper base is coated with said liquid precoat dispersion using an air knife coater, and a diazo photosensitive layer is formed on this precoat layer formed by drying, thus permitting the resin particles to have superior light regions, and the image formed to be enhanced in witheness, opacity, and image contrast. |
