| 摘要 |
<p>Jute, polyester, polyamide, glass fibre, etc. impregnated with a resin such as a urea or a melamine resin, or a mixt. of these having a humidity content of =12 wt.% are used to bond laminates contg. a number of wood panels. The prods. are used for doors and partitions which are proof against severe mechanical loading such as breaking-in and gunshots from close range. A stack is formed of wood panels 1.0-1.6mm. thick between which the resin impregnated layers are positioned alternately, and is subjected to a temp. of 90-130 degrees C at a pressure of 88.263 N/cm2 to 259-807 N/cm2, so that simultaneously the resin is reacted and the layers are bonded. No bakelising penetration of the wood panels is allowed, and pref. the reinforcement layers impregnated with resin are sprinkled with particles having an abrasive action. The prod. is cheaper, lighter in weight and much more easily tooled than the conventional armour-plated doors.</p> |
