| 摘要 |
The coating compositions consist of potassium water glass, 8 to 20 % by weight of colloidal silicon dioxide, preferably 10 to 15 % by weight of SiO2 with a weight ratio of SiO2/K<2>O = 2.5 to 6, preferably 4 to 5, 0.1 to 3% by weight of an active hydrophobizing substance based on silanes and polyorganosiloxanes, alternatively with hardening accelerators, 20 to 30% by weight of calcium or magnesium carbonates or their mixtures, 10 to 20% by weight of aluminium, alkali metals, alkali earth, magnesium silicates and silicic oxide, up to 15% by weight of white and colour pigments, added according to the required intensity of the colour. The compositions are produced in the following manner: the inorganic additives and pigments and 0.1 to 3% by weight of the active hydrofobizing substance are added while mixing into 100 to 300 parts of potassium water glass at a concentration of 10 to 40% by weight, with a weight ratio of SiO2/K2O = 1.8 to 2.2. Before use, 100 to 300 parts of the colloidal solution of silicon dioxide, at a concentration of 10 to 30% by weight, is added while mixing into the coating composition. During production, the water glass can be replaced by colloidal silicon dioxide, and vice-versa, silicon dioxide with water glass. Two-component painting compositions are produced from the same constituents, only, before use, the mixture of water glass, colloidal silicon dioxide and active hydrofobizing substance is mixed with inorganic additives and pigments or with hardening accelerators to produce painting compositions with dry matter of about 50% by weight.
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