| 摘要 |
PURPOSE:To improve storage stability and printing resistance, and to prevent environmental pollution, by using an aqueous alkaline solution containing no organic solvent but a water-soluble sulfite as a developing solution for a lithographic plate containing a photosensitive diazo compound. CONSTITUTION:A developing solution to be used for a lithographic plate material having a negative type photosensitive layer containing a photosensitive diazo compound and an organic polymer having 35-300 acid value, contains 0.001-30wt.% water soluble sulfite,<=1wt% organic solvent, and alkali dissolved in water. As said sulfite, alkali metallic sulfite, alkali earth sulfite, and an ammonium salt are preferable. |
