| 摘要 |
PURPOSE:To obtain the title heat insulating material useful as a ceiling material, etc., without damaging heat insulting properties, having further improved strength and deflection in bending by adjusting components of fused slag of blast furnace to make SiO2 and MgO in a specific ratio. CONSTITUTION:Fused silica of blast furnace is blended with an additive for component adjuster to prepare a composition comprising 41-48 % SiO2, 9-13 % Al2O3, 4-11 % MgO, 26-36 % CaO and a very small amount of other components, which is fused for many hours, aged, deaerated and the fused material is made into fibers to give rock wool fibers F. The rock wool fibers are made into a thin felt state by warm air accompanying a binder in such a way that the fibers are not entangled into a lump state to form a rock wool felt sheet S having <=30wt.% content of non-fiber material having >=88mu size, the sheets S are laminated, the laminate is thermally hardened to give rock wool mat M2 having 18-35kg/m<3> density and the mat M2 is processed into the objective heat insulating material. |
