HJSIL® R620 is a kind of hydrophobic fumed silica, treated with HMDS (hexamethyldisilazane). It’s high purity white colloidal powder.
 
Reinforcement of HTV silicone rubber, anti-caking
High hydrophobicity and stable thixotropy, using in coating and ink can prevent from anti-caking, anti-sagging and anti-thixoteopy
Good performance of hydrophobic feature and rheology in adhesives and sealants
Improvement of the free flow of powder coating and anti-caking