| 摘要 |
PURPOSE:To enable a bicolor printing by containing a water soluble or dispersing color forming agent in water fed onto a lithographic plate. CONSTITUTION:When water and ink are fed onto a lithographic plate having an image divided into the hydrophilic part and the lipophilic part to print, a water soluble or dispersing color forming agent is contained in water fed. The color forming agent herein used includes a water paint, a water soluble ink, material initially colored such as sakuranin A, auramin, methylene blue BB, victoria green, methyl violet and chrysoidine 3R, and material, such as silver nitrate and photosensitive diazonium salt, which is initially colorless and will generate color or will be colored later. Also, a printing ink, a paint and a pigment dispersing by nature can be used. |
