| 摘要 |
<p>PROBLEM TO BE SOLVED: To inexpensively obtain a composite board excellent in water resistance and flame retardance and having high strength by adding an isocyanate compound to a material consisting essentially of gypsum and lignocellulose obtained from a wooden material treated as a waste material. SOLUTION: Hemihydrate gypsum power in an amount of 100 pts.wt. is mixed with 3-100 pts.wt., preferably 5-50 pts.wt. lignocellulose fiber obtained from wooden material or bark or its shaven strips and 20-100 pts.wt. water to afford slurry-like material. The slurry-like material is mixed with 1-100 pts.wt., preferably 2-50 pts.wt. isocyanate compound. The resultant slurry is formed into a mat having a definite thickness and the mat is molded by a press equipped with a prescribed mold or a spacer and let stand until gypsum and the isocyanate compound are cured. For example, tolylene diisocyanate, diphenylmethane diisocyanate or naphthalene diisocyanate is used as the isocyanate compound.</p> |
