US Patent 7445667 Aluminum flake pigment

An aluminum flake pigment suitable for use in metallic paints, metallic inks and the like is finely flaked in a grinder to include small aluminum flakes with a maximum dimension of not more than 10 μm, wherein these small aluminum flakes have a mean aspect ratio from 8 to 20. Overall, the aluminum flakes of the aluminum flake pigment preferably have a mean particle size from 3 to 20 μm. The grinder produces the aluminum flake pigment by flaking an aluminum powder in an organic solvent using steel ball grinding media having diameters of 0.3 to 1.0 mm.