High temperature Calcium Silicate Core is a kind of inorganic material with stable physical and chemical performance of high resistant temperature, low thermal Conductivity good effect of insulation for fire and sound-proof, low bulk density, high specific strength and never deformed. The Core can be pieced together arbitrarily and no asbestos absolute. The cores will not sent out any irritant smoke and gas when burned in high temperature. It is a pure green building material. So it is suitable for fireproof and sound insulation door. This kind of material had already widely used as cores of fireproof. And sound insulation doors in various field. The limited fire resistance is up to 90 min, even more than 120min.