| 摘要 |
<p>Covering panels by fusing a powdered resin composition on a metal belt, pref. made of Al 0.07 - 0.15 mm. thick with a textured surface, which then travels with the substrate panels through a calender nip, pref. at 150 - 170 degrees C. The moving belt remains in contact until chilled before diverging to a separate take-up. Pref. a continuous paper is overlaid with the resin coating between subsidiary rolls for impregnation prior to contacting the panels. Esp. for covering particle boards on one or both sides (simultaneously) as a continuous semi-automatic process instead of a multi-stage pressing operation. The equipment is less robust than a press. The thin gauge Al belt responds rapidly to the required temperature swing, and can deform to suit panels with rounded surfaces or edges, is typically 0.40 - 1.50 m wide and up to 1700 m long and moves at about 4 m/min. For distributing 180 - 230 g/m2 resin onto papers weighing 80 - 11 g/m2 for covering boards of 400 kg/m3 to 700 kg/m3.</p> |
