Coating parts is optional for those components that require a higher dielectric resistance, resistance to chipping, or a smooth winding surface.
Fair-Rite offers Parylene coating for select parts. This colorless conformal coating is used on smaller parts due to its higher cost but minimal coating thickness. Fair-Rite currently uses Paralyne-C material:
||8.8 x 1016 ohm-cm
|Dielectric Constant (1 MHz)
|Dissipation Factor (1 MHz)
|Water Absorption (24 hours)
|Coefficient of Friction
|Continuous Operating Temperature
||2.0 x 10-4 cal/sec/cm/°C
|Maximum Operating Temperature
Thermo Set Plastic coating
Fair-Rite also offers the ability to coat parts with epoxy. Due to the minimum coating thickness of 0.005”, this method is reserved for parts that are larger in size (diameters > 9mm).