Precio

A background review of enamel insulation materials and powder coating has been finished in this chapter. It is noted that the traditional magnet wire is produced by liquid paint, which contains both resin and solvent. The normally resin are polyvinyl formal (Formvar), polyurethane, polyamide, polyester, polyester-polyimide, polyamide-polyimide (or amide-imide), and polyimide; the most commonly solvents are aromatic like toluene or xylene, aliphatic hydrocarbon like naphtha, esters of acetic acid like butyl acetate, glycol ethers, alcohols, and some ketones like methyl ethyl ketone.

Powder coating is a possible alternative coating technology to take the place of liquid paint in enamelled wire production. The advantages and challenges of powder coating technology are discussed and the preparation methods for ultrafine particles are reviewed as well. In comparison with traditional liquid coating, powder coating is environmentally friendly and the processes used for powder coating is simplified. The challenges of powder coating are including the competition between particle sizes and flow ability and the formulation limitation. So far, the most common commercial powder coating products are polyester, polyurethane, polyester-epoxy (known as hybrid), straight epoxy (fusion bonded epoxy) and acrylics, all with the particle size above 30 micron. A comprehensive study about the powder coating used in the field of enamel coating is undoubtedly important and desired.

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