Positive working photosensitive lithographic printing plate

摘要

A positive working photosensitive lithographic printing plate comprising an aluminum support and a positive working photosensitive layer, wherein the amount of Si atoms attached to the aluminum support is controlled so as to be in the range of 0.1 to 8 mg/m<2>, thereby enhancing both impression capacity and scumproof property and preventing the non-image area from being whitened and the developer from generating dregs and sludge.