| 摘要 |
PURPOSE:To obtain the building material having the strength and freezing hazard resistance equiv. to the strength and freezing hazard resistance of asbestos, pulp, etc., by using foamed pearlite in place of pulp at the time of extrusion molding of a slurry prepd. by compounding cement, silica sand, clay, and pulp and uniformly mixing an extrusion assistant and water therewith. CONSTITUTION:The foamed pearlite is added in place of pulp fibers to the cement compd. for extrusion-molding consisting of, for example, by weight %, 48 parts cement, 43 parts silica sand, 10 parts clay, 5 parts pulp fiber, and further, 1 part extrusion-molding assistant (methyl cellulose) and 30 parts water. The foamed pearlite is formed by grinding pearlite and rapidly expanding the ground pearlite under heating. The above-mentioned compd. is made into a slurry and the slurry is extrusion-molded to obtain the building material. The inorg. building material having the excellent freezing hazard resistance is extrusion-molding by this method even if fibers of asbestos, pulp, etc., are not used. Although this building material is slightly inferior to the building materials of the conventional method in terms of strength, moisture content, water absorptivity, sp. gr., etc., this material is within the range sufficiently withstandable as the building material. |
