To obtain an inorganic sheet having excellent strength, cracking resistance and freezing-thawing resistance by making a sheet using a stock slurry containing a hydraulic material, a woody reinforcing material and a powdered composition of an ethylene-vinyl acetate copolymer emulsion using a water-soluble cellulosic resin as protective colloid and then hardening the sheet.
The hydraulic material is, e.g. Portland cement, blast furnace cement, silica cement, fly ash cement or alumina cement. The woody reinforcing material is, e.g. wood flour, woody fibers, woody pulp, a bundle of woody fibers, wood wool, wood chips, bamboo fibers, jute or palm fibers. The powdered composition is obtained by powdering and/or granulating the emulsion prepared by emulsion polymerization using a water-soluble cellulosic resin such as a hydroxyalkylcellulose as protective colloid by spray drying or other method and has 20-200 μm average particle diameter. The made sheet is cured and hardened after press forming.
TANABE KATSUMI
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