Electrolytic capacitor and production method therefor

A method for producing an electrolytic capacitor, the electrolytic capacitor including a capacitor element including an anode body and a cathode body each having a foil shape, the anode body including a dielectric layer on a surface of the anode body, the method comprising:

• forming a capacitor element precursor by winding or stacking a separator, the anode body, and the cathode body with the separator interposed between the anode body and the cathode body;
• impregnating the capacitor element precursor with a treatment liquid containing a polyhydric alcohol, a solvent, and a conductive polymer component;
• impregnating the capacitor element precursor with a liquid component after the impregnating of the capacitor element precursor with the treatment liquid;
• and
• forming the capacitor element by dissolving a part of the polyhydric alcohol into the liquid component, wherein:
• the polyhydric alcohol is at least one of the group consisting of glucose, mannitol, sorbitol, xylitol, volemitol, pentaerythritol, trimethylolpropane, and derivatives thereof,
• the liquid component contains an aprotic solvent,
• a content proportion of the aprotic solvent in the liquid component in the impregnating of the capacitor element precursor with the liquid component is more than or equal to 50 mass %, and
• after the forming of the capacitor element, an electric conductivity of the liquid component in which a part of the polyhydric alcohol has been dissolved ranges from 0.1 μS/cm to 500 μS/cm, inclusive.