Silica sol is a kind of ivory-white colloid which isformed by nanometer—grade particles SiO2???dispersed inwater,nontoxic and odorless. Its molecular formular ismSiO2???nH2O; SiO2  colloid particles are very fine, colorlessand transparent. With bigger specific surface of Si02 colloidparticles???silica sol is widely used in precisioncasting???papermaking???textile and coating industries as inorganicadhesive and it is also used for catalyst and skidproof agent.