Detailed Product Description Item Index SiO2 content, dry basis, % ≥98 pH-value 6.0 7.0 D50, μm ≤6.0 BET specific surface area, m2/g 230 250 105°C drying loss, % ≤6.0 SO42- content, % ≤0.5 Total iron content, mg/Kg≤300 DBP absorption cm3/g 3.0-4.0Loss on ignition % ≤7.0Heating loss % ≤4.0-8.0 is suitable for silicone rubber, intermediate of silicone rubber, paints, printing ink, tyre, shoe sole, ...