Patent ID: 7584910

Claim:
A method of preparing a dispersion of aggregate metal oxide particles having a pre-selected average aggregate particle diameter comprising (a) providing aggregate metal oxide particles comprised of fused primary particles having an average aggregate particle diameter and an average primary particle diameter, (b) pre-selecting a desired percent-reduction in the average aggregate particle diameter of the metal oxide particles to provide a pre-selected average aggregate particle diameter, (c) providing a dispersion standard pertaining to a dispersion of the aggregate metal oxide particles, wherein the dispersion standard correlates (i) the solids concentration of the dispersion with (ii) the percent-reduction in the aggregate particle diameter of the aggregate metal oxide particles that occurs when the dispersion is milled in a high-shear mixer, (d) determining a solids concentration that correlates to the pre-selected percent-reduction in the average aggregate particle diameter of the metal oxide particles by reference to the dispersion standard, (e) combining the aggregate metal oxide particles of step (a) with water to provide a dispersion having a solids concentration that is within 10% of the solids concentration determined in step (d), and (f) milling the dispersion in a high-shear milling device to provide a dispersion of aggregate metal oxide particles having about the pre-selected average aggregate particle diameter.