DE1771875B1 - USE OF THE ELECTROPHORETIC PAINTING PROCESS FOR PROTECTIVE PAINTING OF METALLIC VAPORIZED PLASTIC PARTS, IN PARTICULAR FOR LIGHTS AND HEADLIGHTS OF MOTOR VEHICLES - Google Patents

Description

Recently there has been an increasing trend in motor vehicle construction to mechanically less stressed, Parts made of metallized metal are visible from the outside and have a shiny chrome finish To manufacture plastics. The vapor deposition layer can be on the inside as well be applied to the outside of the plastic parts. In the case of an internal coating, however, is the use of transparent plastics is a prerequisite.

To protect the vapor deposition, it is covered with a paint film that is immersed in or Spray process is applied. However, this method has the disadvantage that just to the The lacquer film is applied very thinly, especially against edges that are susceptible to destruction. Particularly in the case of spraying, it depends more or less on the ability of the painter to apply the paint film apply evenly and strongly to all areas.

In the manufacture of motor vehicle headlights or lights, the housing and the The lens is often made in one piece from a transparent plastic, the one forming the lens Area is not also steamed. For optical reasons, this area must not be included be provided with a protective film. Therefore, when painting according to the known methods, it is necessary to cover this area with a template precisely adapted to the shape of the light exit surface. In addition, a so-called painted edge is arranged around the light-emitting surface, which forms the circumferential Forms limitation and at the same time recording of the painting template. The known procedures are therefore cumbersome and to a large extent for painting limited surface areas depending on the craftsmanship of the painter.

ο The invention has the task of providing a method for To show protective coating of plastic parts that are only metal-coated in places, in which the listed Disadvantages do not occur. This object is achieved according to the invention by using the electrophoretic painting process by dipping, in which plastic or paint particles from an emulsion or dispersion are deposited anodically or cathodically, for applying a protective top layer applied in a known manner by vapor deposition and only in places Metal layer covering the plastic parts of motor vehicle lights and headlights.

The painting according to this process can be done fully automatically, which on the one hand the production designed more rationally and on the other hand a more uniform and better quality work is achieved because painting is now independent of the painter's often highly fluctuating work capacity is. In addition to working with painting templates, there is no need for subsequent polishing, as subsequent polishing Rinsing with fully demineralized water is sufficient. The result of this painting process is a Spot-free, cleanly painted part with razor-sharp demarcation from the non-vaporized surface parts.

Both water-soluble paints in the sense of an emulsion serve as a deposition base. H. one Liquid with floating insoluble particles of another liquid, as well as solid particles, which consist of modified natural substances, polymers, polycondensates and polyadducts and in water to form a coarsely dispersed system (suspension), d. H. a liquid with floating insoluble Particles of a solid plastic are processed.

Claims (1)

Claim: Use of the electrophoretic painting process by dipping, with the plastic or Paint particles deposited anodically or cathodically from an emulsion or dispersion to apply a protective topcoat in a known manner by vapor deposition applied and only in places the plastic parts of motor vehicle lights and headlights covering metal layer.