Fiber reinforced cement composition and products and manufacturing process

A fiber reinforced cement composition comprising the following raw materials:

• not less than 25% by mass and not more than 45% by mass of a hydraulic inorganic material, not less than 5% by mass and not more than 12% by mass of a woody reinforcement, not less than 50% by mass and not more than 65% by mass of a siliceous material, wherein a finely dividing inorganic hollow material and/or a finely dividing inorganic spherical material which is an average particle size of not less than 1 μm and not more than 15 μm is not less than 25% by mass and not more than 75% by mass of whole siliceous material consisting of an inorganic hollow material which is an average particle size of not less than 50 μm and not more than 300 μm and/or an inorganic spherical material which is an average particle size of not less than 15 μm and not more than 50 μm and the finely dividing inorganic hollow material and/or the finely dividing inorganic spherical material which is an average particle size of not less than 1 μm and not more than 15 μm.

A process for manufacturing a fiber reinforced cement product comprising the steps of:

• dispersing in water a raw material composition comprising as main raw materials not less than 25% by mass and not more than 45% by mass of a hydraulic inorganic material, not less than 50% by mass and not more than 65% by mass of a siliceous material, not less than 5% by mass and not more than 12% by mass of a woody reinforcement, wherein a finely dividing inorganic hollow material and/or a finely dividing inorganic spherical material which is an average particle size of not less than 1 μm and not more than 15 μm is not less than 25% by mass and not more than 75% by mass of whole siliceous material consisting of an inorganic hollow material which is an average particle size of not less than 50 μm and not more than 300 μm and/or an inorganic spherical material which is an average particle size of not less than 15 μm and not more than 50 μm and the finely dividing inorganic hollow material and/or the finely dividing inorganic spherical material which is an average particle size of not less than 1 μm and not more than 5 μm to give a slurry of the raw materials;
• forming a green mat from the slurry;
• and pressing the green mat by press molding and thereafter curing the mat in an autoclave.