<p>An MF capacitor of an oil impregnation type, whose durability in constant voltage application is so high that it is useful for practical use. The metallized plastic film is impregnated with an electrically insulating oil composition obtained by adding 5-80 wt. % natural fatty acid triglyceride which contains a little amount of fatty acid ester having free hydroxyl radical to aromatic hydrocarbon having a specific chemical structure and being liquid at -30 DEG C.</p>
