| abstract |
FIELD: partially hydrophobic sedimentary silicic acid. SUBSTANCE: partially hydrophobic sedimentary silicic acid is characterized by wettability with methanol from 10 to 49% with absorption of dibutylphthalate in terms of dry matter of more than 250 g/100 g, mean particle sizes from 1 to 12 mcm, and/or with content of carbon from 0.3 to 1.85%, and/or with loss in drying from 2.6 to 10%, and/or with pH 5.5 to 10. Silicic acid is produced by mixing of definite quantity of water-repellant means with suspension of sedimentary silicic acid for very short period of time at low values of pH with subsequent filtering of obtained solid substance, washing from salts, drying, heat treatment of dry substance and grinding. Partially hydrophobic sedimentary silicic acid may be added to compositions of biologically active substance, such as compositions containing sensitive to hydrolysis biologically active substances and foam suppressors. EFFECT: higher efficiency. 15 cl, 7 dwg, 6 tbl |