Abstract: 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 ?m, (2) the powder in the sintered body has a 10% particle size D10 in a number-based particle size distribution of 1.0 to 1.8 ?m, (3) the powder in the sintered body has a 50% particle size D50 in the number-based particle size distribution of 2.0 to 3.5 ?m, and (4) the powder in the sintered body has a 90% particle size D90 in the number-based particle size distribution of 3.8 to 6.0 ?m.

Abstract: 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 ?m, (2) the powder in the sintered body has a 10% particle size D10 in a number-based particle size distribution of 1.0 to 1.8 ?m, (3) the powder in the sintered body has a 50% particle size D50 in the number-based particle size distribution of 2.0 to 3.5 ?m, and (4) the powder in the sintered body has a 90% particle size D90 in the number-based particle size distribution of 3.8 to 6.0 ?m.

Abstract: 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 (ST1) 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 (ST2). 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 (ST3) 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.

Abstract: When manufacturing an electrode for an electrolytic capacitor, in a first hydration step (ST1), an aluminum electrode is immersed in a first hydration processing solution having a temperature of at least 70° 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 (ST2), 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° C.

Abstract: 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 electrode 10 having at least one surface 11 on which a porous layer 17 having a thickness of 200 micrometers or greater is formed is subjected to chemical formation in a chemical formation solution, the aluminum electrode 10 is held by an electrode holder 50. The electrode holder 50 includes: an insulating first support plate 51 configured to overlap the one surface 11 of the aluminum electrode 10; an insulating second support plate 52 configured to overlap the other surface 12 of the aluminum electrode 10; and a connecting part 53 configured to connect the first support plate 51 and the second support plate 52 to each other.

Abstract: 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° C. to 92° 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° C. to 78° C. to form the chemical formation film on the aluminum electrode. In this method, the amount of the hydrated film is made appropriate.

Abstract: 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 (ST1) 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 (ST2). 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 (ST3) 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.

Abstract: 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° 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?t2/t1?1, wherein t1 is the average thickness of the hydrated film formed in a depth range of up to 100 ?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 ?m from the surface of the aluminum electrode.

Abstract: 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° 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° 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?A and the absolute value of the velocity vector B?A is represented by |B?A|, the absolute value |B?A| of the velocity vector satisfies the following conditional formula.

Abstract: When manufacturing an electrode for an electrolytic capacitor, in a first hydration step (ST1), an aluminum electrode is immersed in a first hydration processing solution having a temperature of at least 70° 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 (ST2), 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° C.

Abstract: An aluminum electrode in which a porous layer made of a sintered layer of aluminum powder having an average particle diameter of 1 ?m to 10 ?m is laminated in a thickness of 150 ?m to 3000 ?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.

Abstract: 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 electrode 10 having at least one surface 11 on which a porous layer 17 having a thickness of 200 micrometers or greater is formed is subjected to chemical formation in a chemical formation solution, the aluminum electrode 10 is held by an electrode holder 50. The electrode holder 50 includes: an insulating first support plate 51 configured to overlap the one surface 11 of the aluminum electrode 10; an insulating second support plate 52 configured to overlap the other surface 12 of the aluminum electrode 10; and a connecting part 53 configured to connect the first support plate 51 and the second support plate 52 to each other.

Abstract: 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° 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° 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?A and the absolute value of the velocity vector B?A is represented by |B?A|, the absolute value |B?A| of the velocity vector satisfies the following conditional formula.

Abstract: 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° 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?t2/t1?1, wherein t1 is the average thickness of the hydrated film formed in a depth range of up to 100 ?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 ?m from the surface of the aluminum electrode.

Abstract: 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° C. to 92° 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° C. to 78° C. to form the chemical formation film on the aluminum electrode. In this method, the amount of the hydrated film is made appropriate.

Abstract: An aluminum electrode in which a porous layer made of a sintered layer of aluminum powder having an average particle diameter of 1 ?m to 10 ?m is laminated in a thickness of 150 ?m to 3000 ?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.

Abstract: The present invention provides an electrode material for aluminum electrolytic capacitors and a production method thereof. The electrode material of the present invention is formed of a sintered body of at least one of aluminum or aluminum alloys, and does not require an etching process. The electrode material of the present invention ensures a high capacitance even when the aluminum or aluminum alloy powder has a small particle diameter and the sintered body has a large thickness. Specifically, the present invention provides an electrode material for aluminum electrolytic capacitors, comprising a sintered body of at least one of an aluminum powder and aluminum alloy powders, wherein: the powder has an average particle diameter d50 of 1 to 10 ?m, and the sintered body comprises two or more sintered layers in which average particle diameters d50 of powders contained in adjacent sintered layers have a difference of at least 0.5 ?m.