Nippon Light Metal Company, Ltd.

Toyo Aluminium K.k.

Shuhei Enoki

Toshifumi Taira

Yuta Shimizu

Masahiko Katano

Kazuya Fujimoto

Shinya Sone

When manufacturing an electrode for an electrolytic capacitor, in a first hydration step (ST), an aluminum electrode is immersed in a first hydration processing solution having a temperature of at least 70&#xb0; C. and comprising pure water or an aqueous solution to which phosphoric acid or a phosphate has been added so that the phosphorus concentration is no greater than 4 mass ppm. In a second hydration step (ST), the aluminum electrode is immersed in a second hydration processing solution to which phosphoric acid or a phosphate has been added so that the phosphorus concentration is 4-5000 mass ppm, the second hydration processing solution having a pH of 3.0-9.0 and a temperature of at least 70&#xb0; C. In a chemical conversion step (ST), at least a boric acid chemical conversion process in which the aluminum electrode is chemically converted in a boric acid-based chemical conversion solution is included, and a chemical conversion coating having a coating withstand voltage of at least 200 V is formed on the aluminum electrode.

Electrode for aluminum electrolytic capacitor and method for manufacturing same

An electrode for an aluminum electrolytic capacitor and a method for producing the same are provided that enable improvement of water resistance of a chemical formation film having a withstand voltage of 400 V or higher. The electrode for an aluminum electrolytic capacitor is produced by performing a hydration step of bringing the aluminum electrode into contact with a hydration treatment liquid having a temperature of 78&#xb0; C. to 92&#xb0; C. to form a hydrated film on the aluminum electrode and a chemical formation step of performing chemical formation at a chemical formation voltage of 400 V or higher in a chemical formation solution having a temperature of 58&#xb0; C. to 78&#xb0; C. to form the chemical formation film on the aluminum electrode. In this method, the amount of the hydrated film is made appropriate. In this electrode for an aluminum electrolytic capacitor, the number of voids that are exposed on a cut surface when the chemical formation film is cut is 150 voids/&#x3bc;mor smaller, and thus the water resistance thereof is high.

Electrode for aluminium electrolytic capacitor, and production method therefor

A method for producing an electrode for an aluminum electrolytic capacitor is provided that can reduce defects in a chemical formation film formed at a chemical formation voltage of 500 V or higher. For producing the electrode for an aluminum electrolytic capacitor, an aluminum electrode is brought into contact with pure water having a temperature of 70&#xb0; C. or higher to form a hydrated film having a suitable film thickness on the aluminum electrode at a hydration step, and then chemical formation is performed thereon at a chemical formation voltage of 500 V or higher in a chemical formation solution having a temperature of 40&#xb0; C. or higher at a chemical formation step. At the chemical formation step, when the relative velocity of the chemical formation solution to the aluminum electrode is represented by a three-dimensional velocity vector B&#x2212;A and the absolute value of the velocity vector B&#x2212;A is represented by |B&#x2212;A|, the absolute value |B&#x2212;A| of the velocity vector satisfies the following conditional formula.3 cm/s&#x2264;||&#x2264;100 cm/s

Growing community of inventors

Shizuoka, Japan

Shuhei Enoki