| abstract |
Fumed silica powder, surface treated with a surface treatment agent selected from the group consisting of organosilanes, silazanes, acyclic polysiloxanes, cyclic polysiloxanes, and mixtures thereof, wherein the powder has: a) a number of silanol groups relative to BET surface area dSiOH of at least 0.85 SiOH/nm2, as determined by reaction with lithium aluminium hydride; b) a methanol wettability of more than 40 % by volume of methanol in methanol-water mixture; c) a tamped density of not more than 200 g/L. |