Elektrostatisches Lackieren von Kunststoffteilen zur Minimierung von Oversprayverlusten: Abstract

Painting of plastic substrates is up to now an expensive process. A great deal of the materials bought dearly are trashed. The material utilization rate of the application processes is mostly rather low. An important starting point to improve this situation is the application of the electrostatic coating technology. Within the scope of a R&D project carried out by the Fraunhofer IPA, coordinated by the DFO, and supported by 20 companies, the transfer of the electrostatic coating technology into production processes has been investigated on the basis of three concrete applications. In doing so, the field of knowledge in electrostatic coating of plastic substrates has been expanded substantially. The trials at the Fraunhofer IPA coating test line, and in a production line show that in many cases the application of traditional measures for increasing the electrical conductivity of the plastic substrates (e.g., conductive primer or liquid) is no longer necessary. By using suitable paint materials and innovative techniques, e.g. the employment of racks made of insulating material, contactless grounding by gas electrodes or the employment of repelling electrodes, insulating substrates can be coated directly by electrostatic techniques (e.g., by turbo bells). The potential for reducing the paint consumption is expected to be up to 50 %. For reducing paint sludge, it is expected to be up to 70 %. In addition, the application of electrostatic coating techniques often enables a higher line speed