CHEMICAL COMPOUNDS, NAMELY, SILICA, DISPERSED SILICA AND SILICON DIOXIDE FOR INDUSTRIAL PURPOSES; CHEMICAL FILLERS ON A BASE OF SILICON COMPOUNDS FOR GENERAL PURPOSE USE; CHEMICAL THIXOTROPIC AGENTS ON A BASE OF SILICON COMPOUNDS FOR GENERAL PURPOSE USE; CHEMICAL FREE-FLOW ADDITIVES ON A BASE OF ORGANOSILICON COMPOUNDS TO IMPROVE FLOW OF CHEMICAL SUBSTANCES i