An aqueous dispersion, having a silicon dioxide powder having a silicon
dioxide content of 10 to 60 wt.%, wherein the aqueous dispersion is
stable in the pH range of 2 to 6, the aqueous dispersion additionally
contains at least one compound, which is at least partially soluble in
aqueous solution in the pH range 2 to 6 in the form of polyvalent
cations, these being stable in a silicate-like environment as an anionic
component of the particle surface of the silicon dioxide powder, the
quantity of cation-providing compound in relation to the surface of the
silicon dioxide is 0.001 to 0.1 mg cation-providing compound/m.sup.2
silicon dioxide surface, the cation-providing compound being calculated
as the oxide, and the zeta potential of the aqueous dispersion has values
of less than or equal to zero.