Abstract: Coiled or stacked capacitors preferably of the self-healing type which exhibit very low variation of capacitance over the service life. A capacitor winding is impregnated with an insulating impregnating material. The capacitor housing is then filled with an impregnating filling material which has a higher dielectric constant than the insulating impregnating material.

Abstract: In order to distribute electric charges that build up on the surface of record discs and also to drain them away, a cover sheath is provided for storage of the record disc having at least its surface in contact with the surface of the inserted record disc made of conducting material. The cover sheath can be made of metallized paper or metallized synthetic resin film on the same kind of machinery as is used for making conventional sound record dust covers of paper of synthetic film. If the material is metallized on only one side, it is provided with a cuff around its opening so as to lead charges to the outside where they can be drained away by a conducting storage structure. If the material is metallized on both sides, instead of providing a cuff, electrical connection of the two metallized layers should be provided.