| 摘要 |
<p>PURPOSE:To inexpensively obtain an asbestos-free fiber-reinforced cement board excellent in strength by combining a mixture of pulp fiber and PP fiber with a specified cement matrix. CONSTITUTION:38-50wt.% cement, 32-45wt.% of alpha-quartz powder having >=8000m<2>/g Blaine value, 3-10wt.% of pulp fiber having 200-500ml freeness, 0.1-1.5wt.% of PP fiber having 150-170 deg.C m.p. and water are mixed to prepare a slurry with 12-25% concentration. The slurry is then continuously supplied in layers on a traveling water-permeable belt, water is sucked and removed from the lower surface of belt, and the water content of the layered slurry is controlled to 31-50%. The product is further dehydrated by a making roll to reduce the water content to <=30%. The material is then cut to a plate, the plate is pressed and dehydrated at 200-700kg/cm<2> pressure into a board, the board is cut to the shape of the product and cured at 140-177 deg.C for 10-20hr in an autoclave, and a fiber-reinforced cement board is obtained.</p> |
