Patent ID: 7879145

Claim:
An inorganic composition comprising the following raw materials: not less than 25% by mass and not more than 45% by mass of Portland cement; not less than 25% by mass and not more than 45% by mass of a siliceous material; and not less than 7% by mass and not more than 15% by mass of a woody reinforcement, wherein the siliceous material is a mixture of a siliceous material having not less than 3000 cm 2 /g and not more than 4000 cm 2 /g of a specific surface area of Blaine and a siliceous material having not less than 7000 cm 2 /g and not more than 11000 cm 2 /g of a specific surface area of Blaine, the amount of the siliceous material having not less than 7000 cm 2 /g and not more than 11000 cm 2 /g of a specific surface area of Blaine is not less than 20% by mass and not more than 50% by mass of the whole siliceous material, the woody reinforcement comprises a wood powder and a pulp, and the amount of the wood powder is not less than 10% by mass and not more than 60% by mass of the whole woody reinforcement.