| 摘要 |
<p>The invention relates to an improved composite material, inparticular made of wood and Plaster of Paris. It has greater waterimpermeability which is of paramount importance for making ofbuilding mateirals. The water impermeability is improved by theaddition of a wax emultion to the Plaster of Paris and the woodfibres for making the material.13 claims</p> |
