A highly polished metal surface is coated with a colloidal aqueous dispersion of P.T.F.E. it is force dried and sintered, until a continuous film is formed. These capacitors can withstand higher temperatures than polystyrene film but the material is expensive.

Specifications

Range of values                      up to 0.05μf

Power factor                                                                     0.0002

Operating temperature                                                       up to 250⁰C

Applications: High temperature capacitor. Less costly.