Carbon black, also known as precipitated hydrated silica, is made by reacting liquid sodium silicate with high-quality transparent inorganic acid, filtering, washing with water and drying. The product is white amorphous particles with specific gravity of 0. 186-0.298, melting point of 1780 and refractive index of 1.46. Porous, large internal surface area, large dispersion, acid resistance, alkali resistance, high temperature resistance, good insulation and high dispersion.