Patent DE-102010016926-A1 (DE)
Title: Electrostatic lacquering of electrically non-conductive parts e.g. plastic-, glass- or ceramic parts by surface conductivity-producing layers, comprises dryly coating non-conductive parts with metal conducting and semi-conducting layers
Inventor: BLASEK GERHARD
IPC: B05D1/06
Filed: 2010-05-12
Abstract: The method for electrostatic lacquering (powder coating) of electrically non-conductive parts such as plastic-, glass- or ceramic parts by surface conductivity-producing layers, comprises dryly coating the non-conductive parts with the metal conducting and semi-conducting layers in an atmospheric pressure chemical vapor deposition process using a plasma source under the addition of precursor or precursors and auxiliary gases, where the surface resistance of the surface layer is less than 10 6>omega , and then carrying out a powder coating. The method for electrostatic lacquering (powder coating) of electrically non-conductive parts such as plastic-, glass- or ceramic parts by surface conductivity-producing layers, comprises dryly coating the non-conductive parts with the metal conducting and semi-conducting layers in an atmospheric pressure chemical vapor deposition process using a plasma source under the addition of precursor or precursors and auxiliary gases, where the surface resistance of the surface layer is less than 10 6>omega , and then carrying out a powder coating. The process flow of the parts is carried out individually or multiply in a workpiece carrier with the aid of an overhead conveyor or floor conveyor. The method works as pure atmospheric in-line process, in which a pre-cleaning and/or tempering of the parts (I) take place in a first step, a plasma treatment (II) takes place with a remote plasma and/or a coating with the aid of the remote plasma under the addition of the precursor or precursors and auxiliary gases in a second step, an application of an electric mass potential (III) takes place in a third step, a powder application (IV) takes place by a powder source within a powder cabin in a fourth step, a melting process (V) (a gelling process) is carried out in a fifth step and a hardening step is carried out in a six step or the second to six process steps are successively carried out in a repeated manner. An atmospheric pressure plasma jet is used in normal ambient atmosphere and is generated by a DC discharge, a corona discharge or a dielectric barrier discharge or by a low frequency-, middle frequency, high frequency or microwave discharge. The atmospheric pressure plasma source produces a bundled plasma beam or a wide beam, in which several individual atmospheric pressure plasma sources are summarized to a bundle, so that the plasma beam of the atmospheric pressure plasma source is distributed by a four-jet nozzle and in which individual less-radiating atmospheric pressure plasma sources are arranged next to each other, so that the individual plasma beams unfold their effect in a line next to each other. A low-temperature powder lacquer is used for temperature-sensible parts with applied metal conducting or semi-conducting surface layers with high burning temperatures (over 130[deg] C) and is meltably cross-linked and hardened broadband-infrared radiator or gas heater. The non-conductive parts already coated with powder lacquer is again subjected to a plasma pretreatment with the remote plasma and the coating with the aid of the remote plasma under the addition of the special precursors and auxiliary gases, so that the functional layers such as layers with high hardness-, scratch- and/or wear resistance, layers with self-cleaning effects, layers with catalytic effects, layers with barrier effect, corrosion protection layers, friction-modifying layers, bioactive or biocompatible layers, layers with shielding- or anti-static effect, electrically conducting or electrically insulating layers, layers with special optical properties, or wetting-modifying and adhesion-modifying layers or layers with decorative properties are producible. The applied electrically conducting layers are qualitatively formed, so that the electrically conducting layers are used as starter layer directly or after a first wet-chemical activation for a chemical or electrochemical metallization of insulating substrates (plastic, already powder-lacquered objects, glass and ceramic layers). An independent claim is included for a coating system for electrostatic lacquering (powder coating) of electrically non-conductive parts such as plastic-, glass- or ceramic parts by surface conductivity-producing layers.