To prevent a clogging from being generated and reduce the incidence of a distortion, cracks, fissures, suction marks and the like which occur in a cement product by using a plastic fabric with a specific air permeability to a solid/liquid separation filter and a specific longitudinal and a specific transverse weave aperture (however, at least either of the longitudinal or the transverse weave pattern has weave apertures).
For a solid/liquid separation filter 1, a plastic fabric 11 is used which has 60-200 cc/cm2/sec. air permeability and 0.5 mm or less weave aperture in both the longitudinal and the transverse weave pattern (however, at least either of the longitudinal or the transverse pattern has weave apertures). The plastic fabric 11 which has the specific air permeability and weave aperture as described, has a high solid/liquid separation precision, so that no clogging due to the contained filler of cement slurry occurs. In addition, the plastic fabric 11 is effectively washable as it is a woven fabric and besides shows high bending rigidity and does not fall into a water squeezing opening, even when the fabric 11 is subjected to vacuum water squeezing in a dehydration process, and a cement product from which water is removed by squeezing has no generated distortion, cracks, fissures or the like.
SAKAMOTO YASUSHI
AKIYAMA KATSUNORI
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