Patent ID: 8197642

Claim:
An inorganic board comprising: a cement; a slag containing a silica component; an inorganic lightweight material; a woody reinforcing material; and a xonotlite, wherein total amount of the cement and the slag is 56 to 75 parts by mass and mass ratio of the cement: the slag is approximately 4:6, amount of the xonotlite is 10-29 parts by mass, the amount of woody reinforcing material is 5-15 parts by mass, and the amount of inorganic lightweight material is 2.45-7.5 parts by mass, each amount per 100 parts by mass of the cement, the slag, the inorganic lightweight material, the woody reinforcing material and the xonotlite, and the woody reinforcing material has a diameter of 5-25 μm and a length of 1.5-3.0 mm.