Abstract: The object of the present invention is to provide an inorganic board whose dimensional stability, anti-freezing and fusing properties, and the like are much improved. To attain this object, an inorganic board is manufactured using a method comprising: preparing a raw material slurry by the dispersing of a cementitious material, silica-containing material, woody reinforcement, and mica in water, forming a papered mat by sheet forming the raw material slurry, pressing the papered mat, and curing the pressed papered mat in an autoclave at a temperature higher than 150° C., wherein the mass ratio of the cementitious inorganic material and silica-containing material is set to be in the range of between 35:65 and 45:55, to promote the curing reaction of the inorganic board and improve its dimensional stability and anti-freezing and fusing properties.

Abstract: The object of the present invention is to provide an inorganic board whose dimensional stability, anti-freezing and fusing properties, and the like are much improved. To attain this object, an inorganic board is manufactured using a method comprising: preparing a raw material slurry by the dispersing of a cementitious material, silica-containing material, woody reinforcement, and mica in water, forming a papered mat by sheet forming the raw material slurry, pressing the papered mat, and curing the pressed papered mat in an autoclave at a temperature higher than 150° C., wherein the mass ratio of the cementitious inorganic material and silica-containing material is set to be in the range of between 35:65 and 45:55, to promote the curing reaction of the inorganic board and improve its dimensional stability and anti-freezing and fusing properties.