Patent ID: 7255735

Claim:
Pyrogenically prepared surface-modified silicon dioxide-titanium dioxide mixed oxides produced by a process comprising modifying the surface of pyrogenically prepared silicon dioxide-titanium dioxide mixed oxides with a silica or organosilane surface-modifying agent of formula I or a silane formed by the partial hydrolysis and condensation of an organosilane of formula I: Si(OR) x (OR′) y (OR″) u (OR′″) v (I) wherein: x=0,1,2,3,4 y=0,1,2,3,4 u=0,1,2,3,4 v=0,1,2,3,4 x+y+u+v=4 and R, R′, R″ and R′″ are each independently a C 1 -C 6 alkyl.