| 摘要 |
PURPOSE:To improve strength, surface smoothness, and extrusion-moldability by using fine fibers as the fibers for reinforcing to be added to a matrix consisting of cement, silica sand, extrusion auxiliary and also specifying water content in a composition. CONSTITUTION:Fine fibers with 0.01-5mu diameter and 10-900mu length are blended by 1-10%, by weight, with a base matrix consisting of 100 pts. cement, 50-150 pts. silica sand, and 0.5-3.0 pts. extrusion auxiliary, and also water content based on the whole composition is regulated to 30-80%. Although, as the above fine fibers, those prepared by fibrillating a synthetic resin film of PP, etc., can be used, those prepared by fibrillating pulp fibers by applying vigorous mechanical shock are particularly preferred. Since this composition is free from deterioration in strength caused by the peeling between the fibers and the matrix due to volume shrinkage attendant on the setting of the cement and also free from surface roughing due to the exposure of long fibers and further has superior water retentivity, shape-holding property can be maintained even if water content is increased as mentioned above. |
