Nippon Light Metal Company, Ltd.

Toyo Aluminium K.k.

Toyo Aluminium Kabushiki Kaisha

Shinya Sone

Toshifumi Taira

Yuta Shimizu

Masahiko Katano

Kazuya Fujimoto

Shuhei Enoki

Yuya Yoshida

Masashi Mehata

Katsumi Nakashima

Ken Wada

An electrode material for aluminum electrolytic capacitors is disclosed, including a sintered body of at least one powder selected from the group consisting of an aluminum powder and an aluminum alloy powder on at least one surface of an aluminum foil substrate or an aluminum alloy foil substrate, wherein (1) the sintered body has a total thickness of 50 to 900 μm, (2) the powder in the sintered body has a 10% particle size Din a number-based particle size distribution of 1.0 to 1.8 μm, (3) the powder in the sintered body has a 50% particle size Din the number-based particle size distribution of 2.0 to 3.5 μm, and (4) the powder in the sintered body has a 90% particle size Din the number-based particle size distribution of 3.8 to 6.0 μm.

Electrode material for aluminum electrolytic capacitors and method for producing same

In production of an electrode for an aluminum electrolytic capacitor, a hydrated film is formed onto an aluminum electrode including a porous layer by immersing the aluminum electrode into a first hydration treatment liquid having a temperature of 80° C. or more in a first hydration treatment step (ST) and thereafter the aluminum electrode is heated in an atmosphere having a temperature of 150° C. or more and 350° C. or less in a dehydration step (ST). Subsequently, a hydrated film is formed onto the aluminum electrode by immersing the aluminum electrode into a second hydration treatment liquid having a temperature of 80° C. or more in a second hydration treatment step (ST) and thereafter chemical formation of the aluminum electrode is performed at 400 V or more and further 600 V or more in a chemical formation step.

Method for producing electrode for aluminum electrolytic capacitor

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 holder and a method for producing an electrode for an aluminum electrolytic capacitor are provided that enable prevention of exfoliation of a porous layer during chemical formation even when the porous layer is formed on an aluminum electrode so as to have a thickness of 200 micrometers or greater. When an aluminum electrodehaving at least one surfaceon which a porous layerhaving a thickness of 200 micrometers or greater is formed is subjected to chemical formation in a chemical formation solution, the aluminum electrodeis held by an electrode holder. The electrode holderincludes: an insulating first support plateconfigured to overlap the one surfaceof the aluminum electrode; an insulating second support plateconfigured to overlap the other surfaceof the aluminum electrode; and a connecting partconfigured to connect the first support plateand the second support plateto each other. A portion of the first support platethat overlaps the porous layerwhile being in contact therewith is formed with a porous member

Electrode holder, and method for producing electrode for aluminum electrolytic capacitor

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

Provided is a method for producing an electrode for an electrolytic capacitor, the method comprising: a hydration step in which an aluminum electrode is immersed in a hydration treatment solution having a temperature of 80&#xb0; C. or higher; and a chemical conversion step in which the aluminum electrode is subjected to chemical conversion treatment up to a formation voltage of at least 400 V. The hydration treatment solution contains a hydration inhibitor. The thickness of a hydrated film formed in the hydration step satisfies the following condition, 0.6&#x2264;t2/t1&#x2264;1, wherein t1 is the average thickness of the hydrated film formed in a depth range of up to 100 &#x3bc;m from the surface of the aluminum electrode, and t2 is the average thickness s of the hydrated film formed in a deep portion at least 100 &#x3bc;m from the surface of the aluminum electrode.

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

An aluminum electrode in which a porous layer made of a sintered layer of aluminum powder having an average particle diameter of 1 &#x3bc;m to 10 &#x3bc;m is laminated in a thickness of 150 &#x3bc;m to 3000 &#x3bc;m on a surface of an aluminum core material is produced by chemical formation to produce an anode for an electrolytic capacitor. In this process, an organic acid immersion step of immersing the aluminum electrode in an organic acid aqueous solution containing dodecanoic acid, benzoic acid, propanedioic acid, butanedioic acid, (E)-2-butenedioic acid, 2-hydroxypropane-1,2,3-tricarboxylic acid, (E)-1-propene-1,2,3-tricarboxylic acid, or the like is carried out after a pure water boiling step and before a chemical formation step. In the chemical formation step, a phosphoric acid immersion step of immersing the aluminum electrode in an aqueous solution containing phosphate ions is carried out one or more times in the course of raising a film withstand voltage to a chemical formation voltage.

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Osaka, Japan

Shinya Sone