Patent ID: 6841609

Claim:
A formulation comprising: (a) internally porous inorganic oxide particles having i) a median particle size in the range of 0.05 to 3 micron; and ii) porosity such that when an aqueous dispersion of the particles is dried at least 0.5 cc/g of pore volume as measured by BJH nitrogen porosimetry is from pores having a pore size of 600 Å or smaller; and (b) binder; wherein said particles possess a viscosity derived pore volume (PVa) of at least 0.5 cc/g as governed by the relationship: slope = - 2.5 ⁢ ( 1 ρ ⁢ ⁢ s + PVa ) ⁢ ρ ⁢ ⁢ f where the slope is about 2.4 or greater, ρs is the particles skeletal density and ρf is the density of fluid phase of dispersion system in which said particles are added.