| 摘要 |
<p>PURPOSE:To provide a manufacture of a hard cement chip board with good various properties such as density and bending strength. CONSTITUTION:A thermosetting component consisting mainly of alumina cement and anhydrous gypsum and/or hemihydrate gypsum, a cement composite containing portland cement, chipped wood pieces and water are blended, and after these mixtures are press-molded into a predetermined form and before the mixtures start hardening reaction, pressure is released for a short period of time or subjected to decompression and then the aforegoing composite is heat-solidified for manufacturing a hard cement chip board. By the pressure releasing or decompressing process, since moisture, air, or the like contained in the mixtures become possible to be removed efficiently from the mixtures, air or the like becomes difficult to stay in the hard cement chip board manufactured herein, as a result, the various properties of density, bending strength, and the like become possible to be improved.</p> |
