Synthetic silica glass powder

摘要

A synthetic silica glass powder obtained by calcining a silica gel powder obtained by hydrolysis of a tetraalkoxysilane, said synthetic silica glass powder containing from 1x10<-><1> to 1x10<-><4> ppm of boron and having an internal silanol group concentration of at most 150 ppm and an isolated silanol group concentration of at most 5 ppm.