To provide an aqueous dispersion containing metal oxide powder and/or metalloid oxide powder in an amount of 20 to 80 wt.%.
This stable aqueous is characterized in that the metal oxide powder and/or the metalloid oxide powder are contained in the dispersion in the form of primary particle aggregates. The average diameter of the aggregates is 10 to 300 nm, and the average diameter of the primary particles is 5 to 50 nm. The powder includes at least two kinds of powder types. The powder types have the same mark surface electric charges at a prescribed pH-value of the dispersion, and have a zeta electric potential acting on a larger electrostatic repulsion than van der Waals attraction. The average diameters of the primary particles are different by at least 1.5 times between the two powder types. The average aggregate diameter of the second and other powder types in the dispersion is 60 to 150% of that of the first powder type. Each powder type is contained in an amount up to at least 1 wt.% in the dispersion.
SCHARFE THOMAS
LORTZ WOLFGANG DR
