Conductive polymer dispersion liquid, electrolytic capacitor, and method for producing electrolytic capacitor

A method for producing an electrolytic capacitor, the method comprising the steps of:

• preparing an anode foil that includes a dielectric layer, a cathode foil, and a fiber structure;
• preparing a conductive polymer dispersion liquid that contains a conductive polymer component and a dispersion medium;
• producing a separator by applying the conductive polymer dispersion liquid to the fiber structure and then removing at least a portion of the dispersion medium;
• and
• producing a capacitor element by sequentially stacking the anode foil, the separator, and the cathode foil,
• wherein the dispersion medium contains water,
• the fiber structure contains a cellulose fiber in an amount of 40 mass % or more, a synthetic fiber and a paper strengthening agent,
• the synthetic fiber includes at least one selected from the group consisting of a nylon fiber, an aramid fiber, an acrylic fiber, and a polyester fiber,
• the fiber structure has a density of 0.2 g/cm3 or more and less than 0.45 g/cm3, and
• a mass of the conductive polymer component per unit area of the separator is 0.02 mg/cm2 or more.

An electrolytic capacitor comprising:

• an anode foil that includes a dielectric layer;
• a cathode foil;
• and
• a separator that is interposed between the anode foil and the cathode foil,
• wherein the separator contains a fiber structure and a conductive polymer component that is attached to the fiber structure,
• the fiber structure contains a synthetic fiber in an amount of 50 mass % or more, a cellulose fiber in an amount of 10 mass % or more and less than 50 mass %,
• the synthetic fiber includes at least one selected from the group consisting of a nylon fiber, an aramid fiber, an acrylic fiber, and a polyester fiber,
• the fiber structure has a density of 0.2 g/cm3 or more and less than 0.45 g/cm3, and
• a mass of the conductive polymer component per unit area of the separator is 0.02 mg/cm2 or more.

An electrolytic capacitor comprising:

• an anode foil that includes a dielectric layer;
• a cathode foil;
• and
• a separator that is interposed between the anode foil and the cathode foil,
• wherein the separator contains a fiber structure and a conductive polymer component that is attached to the fiber structure,
• the fiber structure contains a cellulose fiber in an amount of 40 mass % or more, a synthetic fiber, and a paper strengthening agent,
• the synthetic fiber includes at least one selected from the group consisting of a nylon fiber, an aramid fiber, an acrylic fiber, and a polyester fiber,
• the fiber structure has a density of 0.2 g/cm3 or more and less than 0.45 g/cm3, and
• a mass of the conductive polymer component per unit area of the separator is 0.02 mg/cm2 or more.