Patent ID: 6337136
Filing Date: 2002-01-08
Classification: B41N,C22C

Abstract:
An aluminum alloy support containing precipitated Si for a lithographic printing plate prepared by homogenization heat-treating an aluminum alloy cast slab, hot rolling the slab to form a hot rolled strip, cold rolling the hot roiled skip without intermediate annealing to form a substrate, graining the substrate, and anodically oxidizing the substrate, said substrate comprising 0.10 to 0.40% of Fe, 0.03 to 0.15% of Si, 0.004 to 0.03% of Cu, and the balance of Al and unavoidable impurities including precipitated Si in an amount no more than 30 ppm, an anodic oxide film from 0.1 to 1.0 &mgr;m thick being formed on the grained surface, said anodic oxide film containing precipitated Si particles in an amount no more than 200/mm2 and having an average particle size of at least 0.5 &mgr;m, and said support having a tensile strength of from 145 to 180 MPa wherein the substrate is resistant to ink staining in the non-image areas.