Cathodic electrophoretic paint

Phosphate solutions containing fluorides are used for processing steel, zinc and aluminium when assembled together, but chromate solutions are generally preferred when aluminium is treated alone. The increasing use of cathodic electrophoretic painting on steel, however, has led to a reassessment of the basic processes and formulations that might be most effective. 

Cathodic electrophoretic paint is the preferred polymeric material used to insulate the carbon fibers as the negative potentials required for deposition avoid any possibility of further oxidative dissolution of the carbon fiber. The usual approach for electrophoretic deposition is to suspend the article being coated in an appropriate suspension of polymer particles and polarising the iton versus a secondary electrode. 

The gold microwire, bearing the preformed sphere at its tip, is immersed in a solution containing cathodic electrophoretic paint (BASF, Cathodip FT83-0250) diluted in a... 

Fig. 8 23 A simplified oompatisoti of the reactions during anodic and cathodic electrophoretic painting.

Qiao, Y, Chen, J., Guo, X. L. et al. 2005. Fabrication of nanoelectrodes for neurophysiology Cathodic electrophoretic paint insulation and focused ion beam milling. Nanotechnology 16 1598-1602. 

Epoxy based primer systems remain the best suited for the corrosion protection of magnesium. Cathodic epoxy electrophoretic paints , chromate inhibited epoxy-polyamide primers and high temperature stoving epoxy sealers are used to provide protection up to 180°C. For higher temperature applications up to 300°C, epoxy silicone or polyimide based systems can be used. 

Cathodic electrodeposition tends to be more costly and involve complex resin chemistry but its increasing adoption since the mid 1970s reflects the ability to offer major advantages in corrosion protection at a justifiable premium. Indeed, the majority of electropriming is performed currently by cathodic deposition. The main advantages of electrophoretic painting may be summarized. 

Electrophoretic paints consist of ionic oligomers dispersed in an organic solvent and usually diluted with water to form an emulsion used for deposition. When cathodic current (for a cationic paint) is driven through a tip connected to a two-electrode cell containing the electropaint solution, the oligomers migrate to the tip and deposit on the surface due to reactions with the reduction... 

Electrocoating The deposition of larger-than-ion electrically charged particles (paint, glass, etc.) from an electrolyte under an applied voltage. The deposition is usually on the cathode (cathodic electrocoating) but can be on the anode (anodic electrocoating) side of the electrolytic cell. Also called Electrophoretic deposition. 

Electrophoretic deposition from an aqueous suspension has generally involved clays, oxide ceramic powders, paint or polymers (Table 3). All are characterised by anodic deposition, although it is possible to deposit paint cathodically . ... 

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