| 摘要 |
<p>A substrate for a planographic printing plate and a method of fabrication thereof. After a surface roughening treatment and before an anodizing treatment, an aluminum alloy plate to be used as the substrate is washed in an alkali solution, and then in an acidic solution. After surface-roughening, overlap points of Fe and Si macularly distributed at the surface of the aluminum alloy plate have a surface coverage of not more than 0.5 %, and there are no more than 800 per 1 mm<2> of overlap points which have sizes larger than 1.6 x 10<-7> mm<2>. The planographic printing plate of the present invention has excellent printing capabilities in that, irrespective of printing conditions, soiling does not occur at a non-image portion of the planographic printing plate. <IMAGE></p> |
