Electrophoresis Principle
The method of electrophoretic coating is one of the most advanced technologies for the surface treatment of metal components. The automotive industry has played the largest role in the development of cathodic electrophoretic coating technology, where the corrosion resistance of vehicle bodies and other components is a key priority for manufacturers.
The high quality of the surface treatment, combined with its economic and environmental advantages, has led to the adoption of this technology in other areas of mechanical engineering and consumer goods manufacturing as well.
System Design / Quotation
To prepare a quotation for electrodialysis cells and membranes, we only require a few details, such as the cell head length and the active membrane length. Alternatively, we can use our system design software to review and optimize your existing configuration.
For this, we require the following information:
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Component height [B]
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Maximum surface area immersed per carrier
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Tank height [H]
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Height between the upper edge of the tank and the paint level
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Paint level and component [I]
We are also happy to assist you with questions regarding quality optimization, production expansion, and problem-solving.
Electrodialysis Cells
Cathodic Electrophoresis (Cataphoresis)
Cataphoresis is a method of electrochemical coating in which the object to be coated is connected as the cathode to a direct-current power supply while immersed in the electrolyte (aqueous paint bath). The positively charged paint ions (cations) are then deposited onto the surface of the workpiece.The electrophoretic cell, equipped with an ion-exchange membrane (plate or tubular type), is connected as the anode. It serves both as the counter-electrode and to maintain the concentration balance in the paint bath.
Technical Description of the Cylindrical Cell
Electrode (Anode)
The EFC-Anodex cylindrical cell is a cylindrical system that serves two functions: it acts as the counter-electrode to the cathode and, through the Anex membrane, enables the continuous removal of excess anions from the cathodic electrophoresis bath.
The cylindrical anode is positioned in the center of the EFC cell, with the design of the lower cover and upper head ensuring precise centering. This design also allows the anode to rotate freely when the upper head’s fastening is loosened. This ensures more uniform wear of the anode material caused by electrochemical dissolution during the cathodic electrophoresis process.
Ion-Exchange Membrane RALEX MEMRANE® Type AMH-HD
The anion-exchange membrane is installed by being potted into the lower cover and upper head and is reinforced with a perforated PP tube. The perforated tube defines the space between the membrane and the electrode to ensure efficient anolyte flow, while its structure allows the required passage of electrical current.
The membrane does not expand, meaning that no usable electrode surface area is lost. In contrast to an extruded membrane, whose expansion can reach up to 15% depending on the bath parameters, the available space in the lower section of the bath is fully utilized. This allows a larger membrane area to be installed per cell. This is particularly advantageous in the bottom section of the system.
Electrodialysis Cell Head
The head assembly ensures the required tightness of the entire system and serves to secure the cell to the edge of the tank. A hose connector located in the center of the anode serves as the inlet for the anolyte. The anolyte return line ensures sufficient and uniform anolyte circulation and the effective removal of oxygen (O₂) generated on the anode surface during the electrochemical process.
The assembly also includes the electrical connection to a direct-current power source.