| 摘要 |
PURPOSE:To improve ink accepting property in a silver image area on an offset printing plate, to reduce contamination in the base of a nonpicture area, and to improve stability of the treating liquid for a long time by incorporating a specified compd. CONSTITUTION:A compd. expressed by formula is added as an agent to give oleophilicity to the treating liquid. In formula, 1 is an integer 1 to 3, m is an integer 0 or 1, and n is an integer 4 to 7. The alkyl group (CnH2n+1) in the molecule end of the compd. is preferably a straight-chain group. n is an any number between 4 to 7. If n<=3, the effect to improve the ink accepting property in a silver image area decreases, and if n>=8, the compd. has bad solubility with a solvent and reduces the effect to improve the ink accepting property. 1 is an any number between 1 to 3. If 1>=4, the compd. has bad solubility with a solvent and reduces the effect to improve the ink accepting property. If m>=2, oleophilicity of the compd. decreases, which reduces the effect to improve the ink accepting property in a silver image area. |
