| abstract |
A partially hydrophobic precipitated silica, characterized by a methanol wettability of 10 to 39%, in particular with a DBP uptake anhydrous of greater than 350 g/100 g and a mean particles sized of 1 to 12 μm and/or a carbon content of 0.3 to 1.85% and/or a loss on drying of 2.6 to 10.0% and/or a pH value of 5.5 to 10.0, is prepared by mixing the amount of water repellent agent with the precipitated silica suspension at very short residence time and low pH value, filtering off the solid substance, washing free of salt, drying, post-treating thermally and milling. The partially hydrophobic precipitated silica can be used in active substance formulations and active substance formulations of hydrolysis-sensitive substance and in defoaming agents. |