ABSTRACT

Nomenclature and Classification of Types . . . . . . . 188

Differences among the Types . . . . . . . . . . . . . . . . . 189

After-Treated Synthetic Amorphous Silicas . . . . . . 191

Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

Improvement of Mechanical Properties . . . . . . . 192

Rheological Additives . . . . . . . . . . . . . . . . . . . . . 192

Carrier Applications . . . . . . . . . . . . . . . . . . . . . . . 192

Surface Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

Pigment Effects . . . . . . . . . . . . . . . . . . . . . . . . . . 193

Electrical Effects . . . . . . . . . . . . . . . . . . . . . . . . . 194

Adsorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

Catalysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

Use of After-Treated SAS for the Improvement

of Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

Other Uses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

Handling of SAS . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

Questions Regarding Registration and Approval . . 197

Toxicology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

Skin Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

Inhalation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

Peroral Intake . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

Pure synthetic silicon dioxide in powdered form is discussed. After a brief history, the significance of this

product group is shown by the total production quantity in the Western hemisphere. A clear classification

of synthetic silicas is given, and the principal differences between thermal and wet-process products are

illustrated. After-treated silicas are also discussed. Various applications of synthetic silicas are described

in detail. Questions about useful handling methods, registration, approval, and toxicology are addressed.