The dielectric spacer between the conductive electrodes of an electrical capacitor is a biaxially oriented film made from a mixture of less than 80 percent by weight of isotactic polypropylene and more than 20 percent by weight of isotactic polybutene-1.
A capacitor employing plural dielectric materials between oppositely facing, distinctly electrically connected plates, or employing interspersed plural dielectric materials outside the space between oppositely facing, distinctly electrically connected plates, wherein one material is a plastic and a second material is a plastic, gas, or vacuum. A method for ameliorating the frequency dependent variation pattern in dielectric behavior, of a single material employed as a dielectric in a capacitor, by employing a plurality of materials between oppositely facing, distinctly electrically connected plates, and/or by employing an interspersed plurality of materials outside the space between oppositely facing, distinctly electrically connected plates.
A method is described by which the residual moisture can be removed from wound capacitors containing dielectric layers of thermoplastic plastic material, the residual moisture being broken down by electrochemical decomposition and the break-down products removed by vacuum. Capacitors which are subjected to this treatment have a longer service life.
