| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject plate excellent in hygroscopic property, moisture- conditioning property and deodorizing property and strength and capable of effectively utilizing powdered charcoal by producing the plate from a composition comprising a blend of charcoal powder with alumina cement, silica powder, pumiceous send and water so as to have a specific water absorption, a specific unit volume weight, a specific flexural strength and a specific compressive strength. SOLUTION: This moisture-preventing plate is obtained from preferably 100 pts.wt. composition which is obtained by compounding preferably 35-40 pts.wt. charcoal powder with preferably 8-20 pts.wt. alumina cement, preferably 0-10 pts.wt. silica powder, preferably 5-15 pts.wt. pumiceous send and preferably 30-40 pts.wt. water. The plate has >=50% water absorption, <=1.0t/m<3> unit volume weight, >=15kg/cm<2> flexural strength and >=30kg/cm<2> compression strength. Although all of white charcoal and black charcoal can be used as the charcoal, it is preferable to use black charcoal which is soft charcoal. |
