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Electrophoretic deposition (EPD), is a term for a broad range of industrial processes which includes electrocoating, e-coating, cathodic electrodeposition, anodic electrodeposition, and electrophoretic coating, or electrophoretic painting. A characteristic feature of this process is that colloidal particles suspended in a liquid medium migrate under the influence of an electric field (electrophoresis) and are deposited onto an electrode. All colloidal particles that can be used to form stable suspensions and that can carry a charge can be used in electrophoretic deposition. This includes materials such as polymers, pigments, dyes, ceramics and metals. The process is useful for applying materials to any electrically conductive surface. The materials which are being deposited are the major determining factor in the actual processing conditions and equipment which may be used. Due to the wide utilization of electrophoretic painting processes in many industries, aqueous EPD is the most common commercially used EPD process. However, non-aqueous electrophoretic deposition applications are known. Applications of non-aqueous EPD are currently being explored for use in the fabrication of electronic components and the production of ceramic coatings. Non-aqueous processes have the advantage of avoiding the electrolysis of water and the oxygen evolution which accompanies electrolysis. ==Uses of EPD== This process is industrially used for applying coatings to metal fabricated products. It has been widely used to coat automobile bodies and parts, tractors and heavy equipment, electrical switch gear, appliances, metal furniture, beverage containers, fasteners, and many other industrial products. EPD processes are often applied for the fabrication of supported titanium dioxide (TiO2) photocatalysts for water purification applications, using precursor powders which can be immobilised using EPD methods onto various support materials. Thick films produced this way allow cheaper and more rapid synthesis relative to sol-gel thin-films, along with higher levels of photocatalyst surface area. In the fabrication of solid oxide fuel cells EPD techniques are widely employed for the fabrication of porous ZrO2 anodes from powder precursors onto conductive substrates. EPD processed have a number of advantages which have made such methods widely used〔"Electrodeposition of nanostructured coatings and their characterization - a review" Sci. Technol. Adv. Mater. 9 (2008) 043001 ((free download) )〕 #The process applies coatings which generally have a very uniform coating thickness without porosity. #Complex fabricated objects can easily be coated, both inside cavities as well as on the outside surfaces. #Relatively high speed of coating. #Relatively high purity. #Applicability to wide range of materials (metals, ceramics, polymers, ) #Easy control of the coating composition. #The process is normally automated and requires less human labor than other coating processes. #Highly efficient utilization of the coating materials result in lower costs relative to other processes. #The aqueous process which is commonly used has less risk of fire relative to the solvent-borne coatings that they have replaced. #Modern electrophoretic paint products are significantly more environmentally friendly than many other painting technologies. Thick, complex ceramic pieces have been made in several research laboratories. Furthermore, EPD has been used to produce customized microstructures, such as functional gradients and laminates, through suspension control during processing.〔(Processing of ceramic materials - shaping ) at Catholic University of Leuven〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Electrophoretic deposition」の詳細全文を読む スポンサード リンク
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