| 摘要 |
PURPOSE:To prevent contamination of printed images and lowering in durability to printing from occurring, by incorporating a colored organic pigment into an image-receiving layer and using acetoacetylated polyvinyl alcohol as a binder, in a blank offset printing plate wherein an image-receiving layer comprising an inorganic pigment and a binder is provided on a base. CONSTITUTION:The image-receiving layer comprising an inorganic pigment and a binder is provided on the base, wherein a colored organic pigment consisting of an azo pigment is incorporated in the layer, and the binder is acetoacetylated polyvinyl alcohol. Accordingly, the image-receiving layer is colored in yellow or the like by the use of the colored organic pigment, thereby enabling to easily discriminate the face and the back side from each other and preventing plate making from being performed on the back side of the blank offset printing plate. Further, the organic pigment enhances adhesion between a hydrophilic drawing material and the image-receiving layer, and can enhance durability to printing. When a mixed system of kaolin and synthetic silica is used as the inorganic pigment in the image-receiving layer, even if contamination of printed images is caused by rubbing of an ink ribbon of a printer against the layer at the time of a plate-making operation, non-image parts can be easily desensitized by etching, and images printed on a printing material are not contaminated. |
