| 摘要 |
<p>Plates for building construction purposes, based on wood chips, etc. bonded by means of synthetic resin, have, mixed with the chips, at least in the surface zones of the plates, powdered plaster of Paris. The surface zones extend to a depth of >0.25 mm. and the proportion of plaster relatively to the wood fibre amts. to 10-200%. In the outer zones of the plates the size of the wood particles is pref. 0.25 mm. In the centre it is somewhat larger and the proportion of resin to wood chips is 6-12 wt.%. Plates are fireproof, relatively cheap, not bulky and have good heat insulating qualities.</p> |
