| abstract |
(57) [Problem] To provide an electrolytic capacitor having long life characteristics and high overvoltage characteristics and capable of being miniaturized. SOLUTION: A capacitor element is formed by winding a cathode foil and an anode foil having a pit having a diameter of 0.1 μm or more through a separator to which polyvinyl alcohol is attached to form a capacitor element. When the electrolyte comes into contact with the electrolyte for electrolytic capacitors, and the electrolyte gels, a gel electrolyte with good adhesion to the dielectric film is obtained up to the inside of the pit of the anode foil, and the life characteristics and overvoltage characteristics are improved. improves. When the electrolytic solution contains boric acid of 40% by weight or less, the overvoltage characteristics are further improved. Furthermore, since a separator having a small thickness can be used, downsizing can be achieved. In addition, since a low-density separator can be used, tan δ can be reduced. |