Processes » CDP coating

Cathodic dip painting/ CDP coating

Cathodic dip painting (CDP) is one of the most preferred surfaces for corrosion protection if cost-efficient and long-lasting protection is necessary. In the painting sector, the CDP surface is either used as the only coating system or it is the basis for further paint applications. CDP in combination with powder coating or wet painting is the classic duplex system.

Benefits of CDP coating

  • High corrosion protection despite low layer thicknesses
  • Painting system which is free of heavy metals
  • Affordable process
  • Even layer spread also at hard to reach places and in cavities (adhesion)
  • Also suited for complex moulded parts and very small parts
  • Comprehensive resistance against fuels, oils and brake fluids
  • Complies with EU-End of Life Vehicle Directive


The Process

Cathodic dip coating is an electro-chemical process. The workpiece is fastened to a frame and dipped successively in different treatment basins. Depending on the material and requirement, we undertake different pre-treatment steps to prepare the workpiece optimally for the coating process. The paint separation is done via an electric current originating from the anode located at the edge of the basin through the conductive paint to the workpiece which is the cathode.

Then the paint is integrated to the coated part in a furnace at 190-220°C. It is furthermore possible to use temperatures over 150°C in our technology hub in Solingen. Specifically, for sensitive parts such as die-cast zinc or certain aluminium alloys, lower temperatures are needed to achieve the highest quality for the workpiece.

Possible materials

Steel, ferrous metals, cast iron, galvanized steel, aluminium, aluminium/die-cast zinc (small parts)

CDP coating/layer thickness

CDP coating can be adjusted to three-layer thickness ranges according to the wishes and specifications provided by our clients:

  • Normal layer: N-CDP layer thickness 10 – 25 µm
  • Special thin layer: S-CDP layer thickness 8 – 15 µm
  • Thick layer: D-CDP layer thickness > 35 µm

With this layer thickness range, we can meet all international specifications in the automotive sector and their suppliers.We commissioned an animated film to visualise the process of CDP coating for you; we made good use of the possibility to let you “look inside the basins”.

For more information, watch our video on CDP coating:

Use the opportunity and find out what CDP coating is.

The film excerpt is part of OFTEC’s introduction. Please register on our portal and watch more films about EBBINGHAUS in the company profile area.