Patent ID: 7306890

Claim:
An aluminum alloy plate for use as a lithographic printing plate, the aluminum alloy plate comprising, in wt %, Fe: 0.1 to 0.6%; Si: 0.02 to 0.2%; Cu: 0.001 to 0.003%; Zn: 0.01 to 0.1%; Mg: 0.021 to 0.1%; Ti: 0.001 to 0.05%, and the remainder aluminum and inevitable impurities, and the aluminum alloy plate comprising a plurality of AlFe intermetallic compound particles in its metal structure, and wherein: an average value of the crystal particle size is 60 μm or less in a direction perpendicular to the rolling direction; the included amounts of Cu, Fe, Zn, and Mg satisfy the relationship: 0.15≧(Zn+Mg−(Fe/10)−Cu); the composition of said AlFe intermetallic compound particles having a particle size of 0.1 μm or above, the value of C/B is 0.35 or above when C is a number of AlFe metastable phase intermetallic compound particles having a ratio of Fe/Al of 0.6 or less, and B is a total number of AlFe intermetallic compound particles; and a value of A/B is 0.2 or above in the case that in said AlFe intermetallic compound particles, A is a number of AlFe intermetallic compound particles having an equivalent-circle diameter of 0.1 to 1.0 μm, and B is a total number of AlFe intermetallic compound particles having a particle size of 0.1 or above.