| 摘要 |
<p>PROBLEM TO BE SOLVED: To shorten pressurizing time to a great extent and improve productivity by a method wherein a mixture of a thermosetting cement composition with comminuted wood chips and water is heated and hardened under the specific pressurized condition. SOLUTION: A rigid cement chip board is made by heating and hardening a specific mixture 1 under the pressurized condition of applying pressure of 35-50kgf/cm<2> (3.4-4.9Mpa) for pressurizing time of 8-10 minutes. The mixture 1 is prepared by mixing a thermosetting cement composition containing a thermosetting component mainly composed of aluminous cement and anhydrous gypsum or hemihydrate gypsum, and containing Portland-cement, with comminuted wood chips and water. The mixture 1 is built up on a formwork 2 and heated under pressure for a predetermined period of time by hot press. After hardened, the mixture 1 is released from the formwork 2 to obtain the rigid cement chip board. Further, by increasing pressure higher than the conventional level, the rigid cement chip board becomes dense, and its quality such as bending strength can be improved.</p> |
