| abstract |
Partial hydrophobic precipitated silicic acids, which have a methanol wettability of 10 to 49%, especially with a DBP absorption free of water greater than 250 g / 100 g and with an average particle size of 1 to 12 microns and / or a carbon content 0.3 to 1.85% and / or a loss of dryness of 2.6 to 10.0% and / or a pH value of 5.5 to 10.0, made by mixing the hydrophobic agent with the suspension of the Silicic acid precipitated during a very short treatment time and at a low pH value, the solid substance is filtered, washed until it is desalted, dried, subsequently heat-treated and ground. The partially hydrophobic precipitated silicic acid can be introduced into active substance formulations as well as into active substance formulations of hydrolytically sensitive substances and defoamers. A procedure for its preparation is also described. |