The preferred choice of raw materials for capacitor films are Polypropylene (PP) and Polyethylene terephthalate (PET), PP. is independent of frequency and temperature (<105°C) and has a high impulse stability- therefore it can be used in AC and DC applications.
Compared to this, PET is heavily dependant on frequency due to its high loss factor and so it is mainly used in DC applications. Both type of Capacitor film are produced by Stretchline where a more perfect crystalline structure is formed and the dielectric strength can be increased.
|Film Types||Range of Thickness|
|Capacitor film for metallizing||2 - 12 µm|
|Capacitor film for impregnation||10 - 12 µm|