| 摘要 |
PROBLEM TO BE SOLVED: To provide an original plate for silver salt offset printing excellent in abrasion resistance of thin lines and in development latitude and hardly producing print-stains by improving surface treatment method for an aluminum support, imparting a physical development core thereto, and at the same time, improving surface hydrophilicity and an adhesive property of silver image. SOLUTION: The original plate for silver salt offset printing is characterized by disposing a silver salt photosensitive layer on an aluminum support which is post-treated with an aqueous solution containing a metal silicate, a physical development core forming material, a nitrate and/or a nitrite in the post- treatment subsequent to anodic oxidation. Furthermore, the original plate for silver salt offset printing is characterized by disposing the silver salt photosensitive layer on an aluminum support which is post-treated with an aqueous solution containing a metal silicate and subsequently post-treated with an aqueous solution containing the physical development core forming material, the nitrate and/or the nitrite in the post-treatment subsequent to the anodic oxidation. |
