| 摘要 |
<p>In electrostatic powder coating, the starting materials used are metal surfaces which are furnished with an oil film for protection against corrosion during storage and transport. The polymer powder is applied to the surface without removing the oil film. The powder layer is then melted in an oven and is finally cured by cooling. The heat applied by the oven should be sufficient to volatilise the oil. An oil is preferably used which remains stable or resistant during the heating process as long as it remains on the workpiece surface. This includes the possibility that individual components or the entire oil diffuse through the powder layer and evaporate during the heating-up process, or alternatively that part or all of the oil quantity remains on the workpiece during the heating process and mixes with the powder layer. In both cases, the quality of the plastic coating is not adversely affected by the oil film.</p> |
