Patent ID: 8871344

Claim:
Silica particles comprising primary particles, the primary particles having a volume average particle diameter of from about 80 nm to about 300 nm, a particle size distribution index (GSDv) of from about 1.10 to about 1.40, an average circularity of from about 0.70 to about 0.92, and a circularity distribution index (CDI) of from about 1.05 to about 1.50, the silica particles comprising primary particles having a circularity of about 0.95 or greater at a proportion of about 10% or less by number of particles, wherein the particle size distribution index GSDv and the circularity distribution index CDI are defined as GSDv =( D 84 v/D 16 v ) 0.5 CDI=( C 84 /C 16) 0.5 where D84v is the particle diameter at an accumulation of 84%, D16v is the particle diameter at an accumulation of 16%, C84 is the circularity at an accumulation of 84%, and C16 is the particle diameter at an accumulation of 16%, and wherein a surface of the silica particles is hydrophobized by using a hydrophobization agent comprising an organosilicon compound having a trimethylsilyl group, and an amount of the hydrophobization agent is from 5% by weight to 80% by weight with respect to the silica particles.