WO2020075733A1 - Method of manufacturing electrode material for aluminum electrolytic capacitor - Google Patents

Method of manufacturing electrode material for aluminum electrolytic capacitor Download PDF

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Publication number
WO2020075733A1
WO2020075733A1 PCT/JP2019/039739 JP2019039739W WO2020075733A1 WO 2020075733 A1 WO2020075733 A1 WO 2020075733A1 JP 2019039739 W JP2019039739 W JP 2019039739W WO 2020075733 A1 WO2020075733 A1 WO 2020075733A1
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Prior art keywords
electrode material
aluminum
powder
film
sintering
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PCT/JP2019/039739
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French (fr)
Japanese (ja)
Inventor
敏文 平
藤本　和也
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東洋アルミニウム株式会社
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Priority to JP2020551180A priority Critical patent/JP7317852B2/en
Priority to CN201980067358.7A priority patent/CN112840422B/en
Publication of WO2020075733A1 publication Critical patent/WO2020075733A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/004—Details
    • H01G9/04—Electrodes or formation of dielectric layers thereon
    • H01G9/048—Electrodes or formation of dielectric layers thereon characterised by their structure
    • H01G9/052—Sintered electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/004—Details
    • H01G9/04—Electrodes or formation of dielectric layers thereon
    • H01G9/048—Electrodes or formation of dielectric layers thereon characterised by their structure
    • H01G9/055—Etched foil electrodes

Definitions

  • the present invention relates to a method for manufacturing an electrode material for an aluminum electrolytic capacitor.
  • aluminum electrolytic capacitors have been widely used in the energy field because of their characteristics.
  • aluminum electrolytic capacitors are used for small electronic devices such as mobile phones, home electric appliances such as TVs, inverter power sources for hybrid vehicles, and electricity storage for wind power generation.
  • a capacitor is used.
  • aluminum electrolytic capacitors are used in various applications and are required to exhibit large capacity characteristics at a voltage according to the applications.
  • Patent Document 1 An aluminum electrolytic capacitor characterized by using an aluminum foil having fine aluminum powder adhered to its surface has been proposed (see Patent Document 1).
  • a smooth aluminum foil having a foil thickness of 15 ⁇ m or more and less than 35 ⁇ m aluminum which is self-similar in a length range of 2 ⁇ m to 0.01 ⁇ m and / or aluminum on which an aluminum oxide layer is formed
  • Patent Document 2 An electrolytic capacitor using an electrode foil to which an aggregate of fine particles is attached is also known (see Patent Document 2).
  • the method of adhering aluminum powder to the aluminum foil by plating and / or vapor deposition disclosed in these documents is not at least sufficient for use in medium- and high-voltage capacitors.
  • an electrode material for an aluminum electrolytic capacitor an electrode material for an aluminum electrolytic capacitor made of at least one sintered body of aluminum and aluminum alloy is disclosed (see Patent Document 3).
  • This sintered body has a peculiar structure formed by sintering a laminated body in which aluminum or aluminum alloy powder particles are laminated while maintaining voids between each other, and therefore has a static structure equivalent to or better than that of a conventional etched foil. It is said that the capacitance can be obtained (paragraph [0012] of Patent Document 3).
  • the capacity of this electrode material can be increased by increasing the amount or thickness of powder to be laminated.
  • an electrode material for an aluminum electrolytic capacitor which comprises forming a film made of a paste composition containing aluminum powder on a substrate, sintering the film, and subjecting the sintered film to an etching treatment.
  • a method for producing an electrode material for an aluminum electrolytic capacitor which comprises forming a film made of a paste composition containing aluminum powder on a substrate, sintering the film, and subjecting the sintered film to an etching treatment.
  • the above method has room for consideration regarding the increase in capacitance.
  • the necking part between the powder and the powder forming the film is dissolved by the etching process, and the surface area increases, but the strength decreases and the film easily collapses.
  • the thickness cannot be increased. Therefore, development of a manufacturing method capable of manufacturing an electrode material having a higher capacity is desired.
  • An object of the present invention is to provide a manufacturing method capable of easily manufacturing an electrode material for an aluminum electrolytic capacitor having a large electrostatic capacity.
  • the present inventor as a result of intensive research to achieve the above object, performs an etching treatment on a powder of aluminum or the like, forms a film made of a paste composition containing the powder on a substrate, and burns the film.
  • the inventors have found that the above-described object can be achieved by the manufacturing method according to the present invention, and have completed the present invention.
  • the present invention relates to the following method for manufacturing an electrode material for an aluminum electrolytic capacitor.
  • a method of manufacturing an electrode material for an aluminum electrolytic capacitor comprising: (1) A first step of subjecting at least one powder of aluminum and aluminum alloy to an etching treatment, (2) A second step of forming a film made of a paste composition containing the powder, a binder resin and a solvent on at least one surface of a substrate, and (3) a third step of sintering the film.
  • a method of manufacturing an electrode material for an aluminum electrolytic capacitor which is characterized.
  • At least one powder of aluminum and an aluminum alloy is subjected to an etching treatment to form a film made of a paste composition containing the powder, a binder resin and a solvent on at least one surface of the base material.
  • an etching treatment to form a film made of a paste composition containing the powder, a binder resin and a solvent on at least one surface of the base material.
  • the sintered film can be formed thick, it is possible to obtain an electrode material for an aluminum electrolytic capacitor having a large electrostatic capacitance as an electrode, and it is possible to increase the capacity of a capacitor manufactured using the electrode material. Becomes
  • FIG. 5 is a diagram showing measurement results of pore diameters of a film after sintering of the electrode materials for aluminum electrolytic capacitors of Example 2 and Comparative Example 2.
  • the vertical axis represents the pore volume (Log Differential Intrusion (mL / g)), and the horizontal axis represents the pore size (Pore size Diameter ( ⁇ m)).
  • FIG. 14 It is a figure which shows the measurement result of the pore diameter of the film after sintering of the electrode material for aluminum electrolytic capacitors of the comparative example 2 and the comparative example 14.
  • the vertical axis represents the pore volume (Log Differential Intrusion (mL / g)), and the horizontal axis represents the pore size (Pore size Diameter ( ⁇ m)).
  • the method for producing an electrode material for an aluminum electrolytic capacitor of the present invention comprises (1) a first step of subjecting at least one powder of aluminum and an aluminum alloy to an etching treatment, and (2) a paste composition containing the powder, a binder resin and a solvent. It includes a second step of forming a film made of a material on at least one surface of the base material, and (3) a third step of sintering the film.
  • a first step of subjecting at least one powder of aluminum and an aluminum alloy to an etching treatment and (2) a paste composition containing the powder, a binder resin and a solvent. It includes a second step of forming a film made of a material on at least one surface of the base material, and (3) a third step of sintering the film.
  • the first step is a step of etching at least one kind of powder of aluminum and aluminum alloy.
  • the raw material aluminum powder for example, an aluminum powder having an aluminum purity of 99.8% by weight or more is preferable, and more preferably 99.9% by weight or more.
  • the raw material aluminum alloy powder include silicon (Si), iron (Fe), copper (Cu), manganese (Mn), magnesium (Mg), chromium (Cr), zinc (Zn), titanium (Ti). ), Vanadium (V), gallium (Ga), nickel (Ni), boron (B), and zirconium (Zr).
  • the content of these elements in the aluminum alloy is preferably 100 ppm by weight or less, and particularly preferably 50 ppm by weight or less.
  • the powder one having an average particle diameter D 50 before sintering of 1 to 15 ⁇ m is preferably used, and more preferably 1.8 to 15 ⁇ m.
  • the powder when it has an average particle diameter D 50 of 3 to 9 ⁇ m, it can be suitably used as an electrode material for a medium-high capacity aluminum electrolytic capacitor.
  • the average particle diameter D 50 in the present specification is the particle diameter corresponding to 50% of all particles in the particle size distribution curve obtained by obtaining the particle diameter and the number of particles corresponding to the particle diameter by the laser diffraction method.
  • the average particle diameter D 50 of the powder after sintering is measured by observing the cross section of the sintered body with a scanning electron microscope. For example, although part of the powder after sintering is in a molten state or powders are connected to each other, a part having a substantially circular shape can be approximately regarded as a particle.
  • the maximum diameter (major axis) of each particle having a substantially circular shape is taken as the particle diameter of the particle, the particle diameter of any 50 particles is measured, and the arithmetic mean of these is calculated after sintering.
  • the average particle diameter of the powder is used.
  • the particle size of the powder obtained by such a method hardly changes as compared with the particle size before sintering.
  • the shape of the powder is not particularly limited, but a spherical shape, a substantially spherical shape, or an irregular shape can be preferably used.
  • the shape of the powder is preferably spherical or substantially spherical. Due to the fact that the powder has a spherical shape or a substantially spherical shape, the division by the thin portion or the thin portion during the etching treatment, which may occur in the case of a scale-like or fibrous shape, is further suppressed. .
  • the powder one manufactured by a known method can be used.
  • the atomizing method, melt spinning method, rotating disk method, rotating electrode method, rapid solidification method and the like can be mentioned, but the atomizing method, particularly the gas atomizing method is preferable for industrial production. That is, it is desirable to use the powder obtained by atomizing the molten metal.
  • the etching treatment is not particularly limited, but chemical etching with an acidic solution or an alkaline solution is preferable. Particularly, in the case of chemical etching using an acidic solution, the surface area can be effectively expanded, and the dispersibility is good, and the paste composition in the second step can be mixed more easily. In the case of chemical etching using an alkaline solution, the surface area can be expanded more effectively, but the powder may easily aggregate.
  • the pore diameter of the pores formed in the powder is preferably 1.3 ⁇ m or less, more preferably 1.1 ⁇ m or less.
  • the pore size of the pores formed in the powder is preferably 0.3 ⁇ m or more, more preferably 0.6 ⁇ m or more.
  • the acidic solution used for the chemical etching with the above acidic solution is not particularly limited, and a known acidic solution such as a mixed acid aqueous solution containing one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid and the like can be used.
  • the concentration of the acidic solution is for aluminum electrolytic capacitor electrode material that shows high capacity in the low voltage region, aluminum electrolytic capacitor electrode material that shows high capacity in the high voltage region, or aluminum electrolytic capacitor that shows high capacity in both regions.
  • the electrode material and the like may be appropriately set according to desired characteristics, but 10 to 40 mass% is preferable.
  • the etching temperature and time may be appropriately adjusted depending on the shape and average particle diameter of the powder, the pore diameter to be formed in the powder by etching, the number of pores, the distribution, the surface area, etc. It is preferably 1 to 210 minutes.
  • the alkaline solution used for the chemical etching with the above alkaline solution is not particularly limited, and for example, an alkaline solution (aqueous solution) such as caustic soda can be used.
  • the concentration of the alkaline solution is for aluminum electrolytic capacitor electrode material that shows high capacity in the low voltage region, aluminum electrolytic capacitor electrode material that shows high capacity in the high voltage region, or for aluminum electrolytic capacitor that shows high capacity in both regions. It may be appropriately set according to an electrode material such as an electrode material exhibiting desired characteristics, but usually about 10 to 40 mass% is preferable.
  • the etching temperature and time may be appropriately adjusted according to the shape and average particle size of the powder, the pore size to be formed in the powder by etching, the number of pores, the distribution, the surface area, etc. It is preferably about 1 to 210 minutes at about 90 ° C.
  • an electrode material having desired characteristics can be obtained.
  • the chemical etching with the alkaline solution has a high ability to dissolve the surface of aluminum and the oxide film, can reduce the average particle diameter D 50 of the aluminum powder of the electrode material, and improves the surface area of the electrode material. it is conceivable that. It is also considered that the chemical etching with the acidic solution dissolves the aluminum surface of the electrode material and simultaneously forms tunnel-shaped etching pits into the aluminum powder.
  • the cleaning liquid is not particularly limited, but, for example, a simple substance or a mixed liquid of organic solvents such as water, ethanol, toluene, ketones and esters can be used. It is preferable to wash with water from the viewpoint of cost. Moreover, you may add additives, such as a surfactant and a neutralizer, to a washing
  • the number of times of washing is not particularly limited, but it is preferably performed plural times. Further, when cleaning is performed a plurality of times, the cleaning liquid may be changed during the cleaning. By performing the washing, the acidic solution, the alkaline solution, or the reaction product of the powder and the solution, etc. can further suppress the deterioration of the characteristics of the electrode material for the aluminum electrolytic capacitor due to remaining on the surface of the powder. You can
  • the powder is further dried after the powder is washed in the first step.
  • At least one kind of powder of aluminum and aluminum alloy is subjected to etching treatment.
  • the second step is a step of forming a film made of the paste composition containing the powder, the binder resin and the solvent on at least one surface of the base material.
  • the above paste composition contains a binder resin and a solvent in addition to the above powder. Any of these may be publicly known or commercially available.
  • the binder resin is not limited, for example, carboxy-modified polyolefin resin, vinyl acetate resin, vinyl chloride resin, vinyl chloride vinyl chloride resin, vinyl alcohol resin, butyral resin, vinyl fluoride resin, acrylic resin, polyester resin, urethane Resins, epoxy resins, urea resins, phenol resins, acrylonitrile resins, cellulose resins, paraffin wax, polyethylene wax, and other synthetic resins or waxes, tars, glues, lacquers, pine resin, beeswax, and other natural resins or waxes can be preferably used.
  • These binder resins include those that volatilize during heating and those that remain with aluminum powder due to thermal decomposition, depending on the molecular weight, type of resin, etc., and can be used properly according to the desired electrostatic characteristics and the like. .
  • solvents can be used as the above solvent.
  • organic solvents such as ethanol, toluene, ketones and esters can be used.
  • the above paste composition may optionally contain other components such as a sintering aid and a surfactant. Any of these may be publicly known or commercially available. By containing the above-mentioned other components in the paste composition, the film can be formed more efficiently.
  • a film is formed by applying the paste composition on at least one surface of the base material.
  • the base material known materials can be widely used as long as they are used as the base material of the electrode material for aluminum electrolytic capacitors. Particularly, aluminum foil can be preferably used.
  • the aluminum foil as the base material is not particularly limited, and for example, pure aluminum or aluminum alloy can be used.
  • the composition of the aluminum foil used in the present invention is silicon (Si), iron (Fe), copper (Cu), manganese (Mn), magnesium (Mg), chromium (Cr), zinc (Zn), titanium ( Ti), vanadium (V), gallium (Ga), nickel (Ni), and boron (B) at least one type of alloying element added within the required range, or the content of the above unavoidable impurity elements is limited.
  • the purity of the aluminum foil is preferably 99.8% by weight or more, more preferably 99.9% by weight or more.
  • the purity of the aluminum foil may be the same as or different from the purity of the aluminum powder, but is preferably different in order to improve the strength after sintering between the aluminum foil and the powder.
  • the thickness of the aluminum foil is not particularly limited, but it is preferably in the range of 5 ⁇ m or more and 100 ⁇ m or less, particularly 10 ⁇ m or more and 50 ⁇ m or less.
  • the above aluminum foil one manufactured by a known method can be used. For example, a molten metal of aluminum or aluminum alloy having the above-mentioned predetermined composition is prepared, and the ingot obtained by casting the molten metal is appropriately homogenized. Then, the aluminum foil can be obtained by subjecting this ingot to hot rolling and cold rolling.
  • intermediate annealing may be performed in the range of 50 ° C. or higher and 500 ° C. or lower, particularly 150 ° C. or higher and 400 ° C. or lower during the cold rolling process. Further, after the cold rolling step, an annealing treatment may be performed within a range of 150 ° C. or higher and 650 ° C. or lower, particularly 350 ° C. or higher and 550 ° C. or lower to obtain a soft foil.
  • the film is formed on at least one side of the substrate.
  • the film is preferably formed on both sides of the base material.
  • the film is not formed on the entire surface of the base material. That is, when the coating is formed on the surface of the base material, when viewed in a direction perpendicular to the surface of the base material, the area of the base material is larger than the area of the coating, and the coating is formed on the surface of the base material. It is preferable that there is a portion that is not present. With this configuration, handling when performing a roll-to-roll process is further improved. Specifically, it is possible to further suppress breakage of the base material during chemical conversion treatment for forming an oxide film on the surface of the electrode material for an aluminum electrolytic capacitor.
  • the total thickness of the film is preferably 30 to 2000 ⁇ m, more preferably 60 to 2000 ⁇ m.
  • the total thickness of this film is preferably set so that the total thickness of the sintered body finally obtained through rolling and sintering is 30 to 2000 ⁇ m. These values apply to both cases of forming on one side or both sides of the substrate, but when forming on both sides, the thickness of the coating on one side is 1 / th of the total thickness (including the thickness of the substrate). It is preferably 3 or more.
  • the average thickness of the above film is the average value of 5 points obtained by measuring 7 points with a micrometer and excluding the maximum and minimum values.
  • the coating may be dried at a temperature within the range of 20 to 300 ° C., if necessary.
  • the method for forming the film is not particularly limited, and a conventionally known method can be adopted.
  • the paste composition may be formed into a film by using a coating method such as roller, brush, spray, dipping, or may be formed by a known printing method such as silk screen printing or die coating.
  • a film made of a paste composition containing at least one powder of aluminum and aluminum alloy, a binder resin and a solvent is formed on at least one surface of the base material.
  • the third step is a step of sintering the film.
  • the sintering temperature is preferably 560 to 660 ° C, more preferably 570 to 650 ° C, even more preferably 580 to 620 ° C.
  • the sintering time varies depending on the sintering temperature and the like, it can be appropriately determined usually within the range of about 5 to 24 hours.
  • the sintering atmosphere is not particularly limited and may be, for example, a vacuum atmosphere, an inert gas atmosphere, an oxidizing gas atmosphere (atmosphere), a reducing atmosphere, or the like, but a vacuum atmosphere or a reducing atmosphere is particularly preferable. preferable.
  • the pressure condition may be normal pressure, reduced pressure or increased pressure.
  • the film is sintered in the third step, and that the base material and the film after sintering are joined together.
  • the electrode material for an aluminum electrolytic capacitor can be manufactured more easily.
  • an aluminum foil is used as a base material, a forming film is formed on at least one surface of the aluminum foil in the second step, the film is sintered in the third step, and the film after sintering is formed. And the aluminum foil is joined.
  • a heat treatment (degreasing treatment) with a holding time of 5 hours or longer is performed in advance in a temperature range of 100 ° C. or higher and 600 ° C. or lower in advance of the third step after the second step.
  • the heat treatment atmosphere is not particularly limited, and may be, for example, a vacuum atmosphere, an inert gas atmosphere, or an oxidizing gas atmosphere.
  • the pressure condition may be normal pressure, reduced pressure or increased pressure.
  • the film formed on at least one surface of the base material is sintered.
  • An electrode material for an aluminum electrolytic capacitor is manufactured by the manufacturing method of the present invention. Since the aluminum electrolytic capacitor electrode material manufactured by the manufacturing method of the present invention has a large capacitance per volume, it is possible to downsize a capacitor manufactured using the electrode material. Further, since the sintered film is formed thick, it becomes an electrode material for an aluminum electrolytic capacitor having a large electrostatic capacitance as an electrode, and it becomes possible to increase the capacity of a capacitor manufactured using the electrode material. .
  • the pore size of the sintered film sintered in the third step is 1.3 ⁇ m.
  • the following is preferable, and 1.1 ⁇ m or less is more preferable.
  • the upper limit of the pore diameter of the film after sintering is in the above range, the surface area of the capacitor electrode material manufactured by the manufacturing method of the present invention can be further increased, and the capacity and the capacity per volume can be further increased. It becomes a high electrode material for aluminum electrolytic capacitors.
  • the pore size of the film after sintering is preferably 0.3 ⁇ m or more, more preferably 0.6 ⁇ m or more. When the lower limit of the pore diameter of the film after sintering is in the above range, the capacitance of the obtained capacitor electrode material is further improved.
  • the pore size of the film after sintering of the electrode material for aluminum electrolytic capacitors is measured by the mercury injection method as an example.
  • other measuring methods such as the gas adsorption method are not excluded, and an appropriate measuring method is selected according to the pore size.
  • the pore diameter has a distribution, but the pore diameter of the peak with a large pore volume is adopted as the pore diameter in the measurement target.
  • the pore diameter closest to the pore diameter measured by electron microscope observation or the like is adopted.
  • the electrode materials of Examples and Comparative Examples were manufactured according to the following procedure.
  • the capacitance of the obtained electrode material was measured by the following measuring method.
  • Capacitance After subjecting the electrode material to chemical conversion treatment in an aqueous boric acid solution (50 g / L) at voltages of 250, 550 and 700 V, the capacitance was measured with an ammonium borate aqueous solution (3 g / L). The measured projected area was 10 cm 2 .
  • the pore diameter of the film after sintering of the electrode material was measured using a pore distribution measuring device (AutoPore IV 9500 manufactured by Micromeritics). Among the obtained measurement results, the pore diameter (Pore size Diameter ( ⁇ m)) of the peak with the largest pore volume (Log Differential Intrusion (mL / g)) was taken as the pore diameter of the film after sintering of the electrode material. .
  • Comparative Example 1 An aluminum powder having an average particle diameter D 50 of 15.0 ⁇ m (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHZL530C) was mixed with an ethylcellulose-based binder resin and a solvent (butyl acetate) to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity 99.99% by weight) having a thickness of 30 ⁇ m using a comma coater so that the thickness of the film after sintering was 50 ⁇ m. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 ⁇ m.
  • the average particle size of the aluminum powder was obtained by using Microtrac MT3300EXII (manufactured by Nikkiso Co., Ltd.) and measuring the particle size distribution on a volume basis by a laser analysis method to calculate an average particle size D 50 .
  • Comparative example 2 An aluminum powder having an average particle size D 50 of 9.0 ⁇ m (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHZL560F), an ethylcellulose-based binder resin, and a solvent (butyl acetate) were mixed to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity of 99.99% by weight) having a thickness of 30 ⁇ m using a comma coater so that the thickness of the film after sintering was 50 ⁇ m. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 ⁇ m.
  • Comparative Example 3 An aluminum powder having an average particle diameter D 50 of 3.0 ⁇ m (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHZL58FN) was mixed with an ethylcellulose-based binder resin and a solvent (butyl acetate) to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity 99.99% by weight) having a thickness of 30 ⁇ m using a comma coater so that the thickness of the film after sintering was 50 ⁇ m. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 ⁇ m.
  • Comparative Example 4 An aluminum powder (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHU091) having an average particle diameter D 50 of 1.8 ⁇ m was mixed with an ethylcellulose-based binder resin and a solvent (butyl acetate) to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity of 99.99% by weight) having a thickness of 30 ⁇ m using a comma coater so that the thickness of the film after sintering was 50 ⁇ m. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 ⁇ m.
  • Example 1 An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 2 An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 3 An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 4 An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 5 An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions. Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
  • Example 6 An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions. Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
  • Example 7 An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions. Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
  • Example 8 An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions. Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
  • Example 9 An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
  • Example 10 An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
  • Example 11 An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
  • Example 12 An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
  • Example 13 An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
  • Example 14 An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
  • Example 15 An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
  • Example 16 An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions. Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
  • Comparative Example 5 An electrode material was prepared in the same manner as in Comparative Example 1 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 30 ⁇ m.
  • Comparative Example 6 An electrode material was prepared in the same manner as in Comparative Example 2 except that the composition was applied symmetrically on both sides of the aluminum foil base material such that the thickness of the film after sintering was 30 ⁇ m.
  • Comparative Example 7 An electrode material was prepared in the same manner as in Comparative Example 3 except that the composition was applied symmetrically on both sides of the aluminum foil base material such that the thickness of the film after sintering was 30 ⁇ m.
  • Comparative Example 8 An electrode material was prepared in the same manner as in Comparative Example 4 except that the composition was applied symmetrically on both sides of the aluminum foil substrate so that the thickness of the film after sintering was 30 ⁇ m.
  • Example 17 An electrode material was prepared in the same manner as in Comparative Example 5 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 18 An electrode material was prepared in the same manner as in Comparative Example 6 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 19 An electrode material was prepared in the same manner as in Comparative Example 7 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 20 An electrode material was prepared in the same manner as in Comparative Example 8 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Comparative Example 9 An electrode material was prepared in the same manner as in Comparative Example 1 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 ⁇ m.
  • Comparative Example 10 An electrode material was prepared in the same manner as in Comparative Example 2 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 ⁇ m.
  • Comparative Example 11 An electrode material was prepared in the same manner as in Comparative Example 3 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 ⁇ m.
  • Comparative Example 12 An electrode material was prepared in the same manner as in Comparative Example 4, except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 ⁇ m.
  • Example 17 An electrode material was prepared in the same manner as in Comparative Example 9 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 18 An electrode material was prepared in the same manner as in Comparative Example 10 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 19 An electrode material was prepared in the same manner as in Comparative Example 11 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Example 20 An electrode material was prepared in the same manner as in Comparative Example 12 except that the aluminum powder was etched under the following conditions. Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
  • Comparative Example 13 (Example 1 of JP-A-2014-138159) An electrode material was prepared in the same manner as in Comparative Example 3 except that the electrode material after sintering was subjected to etching treatment under the following conditions. Etching solution: mixed solution of hydrochloric acid and sulfuric acid (hydrochloric acid concentration: 1 mol / L, sulfuric acid concentration: 3 mol / L, concentration 15%), temperature: 40 ° C., time: 2 min
  • Comparative Example 14 (Example 9 of JP-A-2014-138159) An electrode material was prepared in the same manner as in Comparative Example 2 except that the electrode material after sintering was subjected to etching treatment under the following conditions. Etching solution: mixed solution of hydrochloric acid and sulfuric acid (hydrochloric acid concentration: 1 mol / L, sulfuric acid concentration: 3 mol / L, concentration 15%), temperature: 40 ° C., time: 2 min

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Abstract

Provided is a method that is capable of easily manufacturing an electrode material for aluminum electrolytic capacitors having a large electrostatic capacity. This method of manufacturing an electrode material for aluminum electrolytic capacitors is characterized by including (1) a first step of subjecting at least one type of powder among aluminum and aluminum alloy to etching, (2) a second step of forming, on at least one surface of a substrate, a coating comprising a paste composition that includes the powder, a binder resin, and a solvent, and (3) a third step of sintering the coating.

Description

アルミニウム電解コンデンサ用電極材の製造方法Method for manufacturing electrode material for aluminum electrolytic capacitor
　本発明は、アルミニウム電解コンデンサ用電極材の製造方法に関する。 The present invention relates to a method for manufacturing an electrode material for an aluminum electrolytic capacitor.
　従来、アルミニウム電解コンデンサは、その特性からエネルギー分野で広く用いられており、例えば、携帯電話等の小型電子機器、テレビ等の家庭電化製品、ハイブリッド車のインバーター電源や風力発電の蓄電等にアルミニウム電解コンデンサが使用されている。このように、アルミニウム電解コンデンサは様々な用途で用いられ、その用途に応じた電圧で大容量の特性を示すことが要求される。 Conventionally, aluminum electrolytic capacitors have been widely used in the energy field because of their characteristics.For example, aluminum electrolytic capacitors are used for small electronic devices such as mobile phones, home electric appliances such as TVs, inverter power sources for hybrid vehicles, and electricity storage for wind power generation. A capacitor is used. As described above, aluminum electrolytic capacitors are used in various applications and are required to exhibit large capacity characteristics at a voltage according to the applications.
　表面に微細なアルミニウム粉末を付着させたアルミニウム箔を用いたことを特徴とするアルミニウム電解コンデンサが提案されている（特許文献１参照）。また、箔厚が１５μｍ以上３５μｍ未満である平滑なアルミニウム箔の片面又は両面に、２μｍ～０．０１μｍの長さ範囲で自己相似となるアルミニウム及び／又は表面に酸化アルミニウム層を形成したアルミニウムからなる微粒子の凝集物が付着した電極箔を用いた電解コンデンサも知られている（特許文献２参照）。 An aluminum electrolytic capacitor characterized by using an aluminum foil having fine aluminum powder adhered to its surface has been proposed (see Patent Document 1). In addition, on one or both sides of a smooth aluminum foil having a foil thickness of 15 μm or more and less than 35 μm, aluminum which is self-similar in a length range of 2 μm to 0.01 μm and / or aluminum on which an aluminum oxide layer is formed An electrolytic capacitor using an electrode foil to which an aggregate of fine particles is attached is also known (see Patent Document 2).
　しかしながら、これらの文献で開示されているメッキ及び／又は蒸着によりアルミニウム粉末をアルミニウム箔に付着させる方法では、少なくとも、中高圧用のコンデンサ用途に用いるのには十分なものとは言えない。 However, the method of adhering aluminum powder to the aluminum foil by plating and / or vapor deposition disclosed in these documents is not at least sufficient for use in medium- and high-voltage capacitors.
　また、アルミニウム電解コンデンサ用電極材として、アルミニウム及びアルミニウム合金の少なくとも１種の焼結体からなるアルミニウム電解コンデンサ用電極材が開示されている（特許文献３参照）。この焼結体は、アルミニウム又はアルミニウム合金の粉末粒子が互いに空隙を維持しながら積層された積層体を焼結してなる特異な構造を持つことから、従来のエッチド箔と同等又はそれ以上の静電容量を得ることができるとされている（特許文献３の［００１２］段落）。この電極材は、積層させる粉末の量または厚みを増やすことで容量を増加させることができる。 Further, as an electrode material for an aluminum electrolytic capacitor, an electrode material for an aluminum electrolytic capacitor made of at least one sintered body of aluminum and aluminum alloy is disclosed (see Patent Document 3). This sintered body has a peculiar structure formed by sintering a laminated body in which aluminum or aluminum alloy powder particles are laminated while maintaining voids between each other, and therefore has a static structure equivalent to or better than that of a conventional etched foil. It is said that the capacitance can be obtained (paragraph [0012] of Patent Document 3). The capacity of this electrode material can be increased by increasing the amount or thickness of powder to be laminated.
　しかしながら、近年、コンデンサに求められる性能がより厳しくなっている。上述の電極材は、厚みを厚くすることで電極材の静電容量が増加するが、体積あたりの静電容量では不十分となりつつあるという問題がある。 However, in recent years, the performance required for capacitors has become more severe. The above-mentioned electrode material increases the capacitance of the electrode material by increasing the thickness, but there is a problem that the capacitance per volume is becoming insufficient.
　また、アルミニウムの粉末を含むペースト組成物からなる皮膜を基材上に形成し、当該皮膜を焼結し、焼結された皮膜にエッチング処理を施すアルミニウム電解コンデンサ用電極材の製造方法が開示されている（特許文献４参照）。この製造方法によれば、用いるアルミニウム粉末の平均粒径にかかわらず、体積あたりの静電容量が大きく、薄膜化可能なアルミニウム電解コンデンサ用電極材を製造することができることが記載されている。 Also disclosed is a method for producing an electrode material for an aluminum electrolytic capacitor, which comprises forming a film made of a paste composition containing aluminum powder on a substrate, sintering the film, and subjecting the sintered film to an etching treatment. (See Patent Document 4). According to this manufacturing method, it is described that an electrode material for an aluminum electrolytic capacitor, which has a large capacitance per volume and can be made into a thin film, can be manufactured regardless of the average particle diameter of the aluminum powder used.
　しかしながら、上述の方法は、静電容量の増加については検討の余地がある。焼結された皮膜にエッチング処理を施す際に、皮膜を構成する粉末と粉末の間のネッキング部がエッチング処理により溶解され、表面積は増大するものの、強度が低下し皮膜が崩れやすくなるため、皮膜の厚みを厚く出来ないという問題がある。そのため、より高い容量の電極材を製造することができる製造方法の開発が望まれている。 However, the above method has room for consideration regarding the increase in capacitance. When etching the sintered film, the necking part between the powder and the powder forming the film is dissolved by the etching process, and the surface area increases, but the strength decreases and the film easily collapses. There is a problem that the thickness cannot be increased. Therefore, development of a manufacturing method capable of manufacturing an electrode material having a higher capacity is desired.
特開平２－２６７９１６号公報JP-A-2-267916 特開２００６－１０８１５９号公報JP, 2006-108159, A 特開２００８－９８２７９号公報JP, 2008-98279, A 特開２０１４－１３８１５９号公報JP, 2014-138159, A
　本発明は、静電容量の大きいアルミニウム電解コンデンサ用電極材を容易に製造することができる製造方法を提供することを目的とする。 An object of the present invention is to provide a manufacturing method capable of easily manufacturing an electrode material for an aluminum electrolytic capacitor having a large electrostatic capacity.
　本発明者は、上記目的を達成すべく鋭意研究を進めた結果、アルミニウム等の粉末にエッチング処理を施し、当該粉末を含むペースト組成物からなる皮膜を基材上に形成し、当該皮膜を焼結する製造方法によれば上記目的を達成できることを見出し、本発明を完成するに至った。 The present inventor, as a result of intensive research to achieve the above object, performs an etching treatment on a powder of aluminum or the like, forms a film made of a paste composition containing the powder on a substrate, and burns the film. The inventors have found that the above-described object can be achieved by the manufacturing method according to the present invention, and have completed the present invention.
　即ち、本発明は、下記のアルミニウム電解コンデンサ用電極材の製造方法に関する。
１．アルミニウム電解コンデンサ用電極材の製造方法であって、
（１）アルミニウム及びアルミニウム合金の少なくとも１種の粉末にエッチング処理を施す第１工程、
（２）前記粉末、バインダ樹脂及び溶剤を含むペースト組成物からなる皮膜を基材の少なくとも一方の面に形成する第２工程、及び
（３）前記皮膜を焼結する第３工程
を含むことを特徴とする、アルミニウム電解コンデンサ用電極材の製造方法。
２．前記エッチング処理は、酸性溶液又はアルカリ性溶液による化学エッチングである、項１に記載の製造方法。
３．前記エッチング処理は、酸性溶液による化学エッチングである、項１に記載の製造方法。
４．前記粉末の平均粒径Ｄ５０が１～１５μｍである、項１～３のいずれかに記載の製造方法。
５．前記焼結の温度は、５６０℃以上６６０℃以下である、項１～４のいずれかに記載の製造方法。
６．前記焼結後の前記皮膜の厚みが３０～２０００μｍである、項１～５のいずれかに記載の製造方法。
７．前記焼結後の前記皮膜の細孔径は、１．３μｍ以下である、項１～６のいずれかに記載の製造方法。 That is, the present invention relates to the following method for manufacturing an electrode material for an aluminum electrolytic capacitor.
1. A method of manufacturing an electrode material for an aluminum electrolytic capacitor, comprising:
(1) A first step of subjecting at least one powder of aluminum and aluminum alloy to an etching treatment,
(2) A second step of forming a film made of a paste composition containing the powder, a binder resin and a solvent on at least one surface of a substrate, and (3) a third step of sintering the film. A method of manufacturing an electrode material for an aluminum electrolytic capacitor, which is characterized.
2. Item 2. The manufacturing method according to Item 1, wherein the etching treatment is chemical etching using an acidic solution or an alkaline solution.
3. Item 2. The manufacturing method according to Item 1, wherein the etching treatment is chemical etching using an acidic solution.
4. Item 4. The production method according to any one of Items 1 to 3, wherein the average particle diameter D 50 of the powder is 1 to 15 μm.
5. Item 5. The manufacturing method according to any one of Items 1 to 4, wherein the sintering temperature is 560 ° C or higher and 660 ° C or lower.
6. Item 6. The method according to any one of Items 1 to 5, wherein the thickness of the film after the sintering is 30 to 2000 μm.
7. 7. The manufacturing method according to any one of Items 1 to 6, wherein the pore size of the film after the sintering is 1.3 μm or less.
　本発明によれば、アルミニウム及びアルミニウム合金の少なくとも１種の粉末にエッチング処理を施し、当該粉末、バインダ樹脂及び溶剤を含むペースト組成物からなる皮膜を基材の少なくとも一方の面に形成し、当該皮膜を焼結することにより、体積あたりの静電容量が大きいアルミニウム電解コンデンサ用電極材を得ることができる。このため、当該電極材を用いて製造されるコンデンサを小型化することが可能となる。 According to the present invention, at least one powder of aluminum and an aluminum alloy is subjected to an etching treatment to form a film made of a paste composition containing the powder, a binder resin and a solvent on at least one surface of the base material. By sintering the film, it is possible to obtain an electrode material for an aluminum electrolytic capacitor having a large capacitance per volume. Therefore, it is possible to downsize the capacitor manufactured using the electrode material.
　また、焼結した皮膜を厚く形成できるので、電極としての静電容量が大きいアルミニウム電解コンデンサ用電極材を得る事ができ、当該電極材を用いて製造されるコンデンサを大容量化することが可能となる。 Also, since the sintered film can be formed thick, it is possible to obtain an electrode material for an aluminum electrolytic capacitor having a large electrostatic capacitance as an electrode, and it is possible to increase the capacity of a capacitor manufactured using the electrode material. Becomes
本発明の製造方法の第１工程における、エッチング処理前の粉末（ＡＨＺＬ５６０Ｆ）のＳＥＭ写真（二次電子像）を示す図である。It is a figure which shows the SEM photograph (secondary electron image) of the powder (AHZL560F) before an etching process in the 1st process of the manufacturing method of this invention. 本発明の製造方法の第１工程における、エッチング処理後の粉末（ＡＨＺＬ５６０Ｆ）のＳＥＭ写真（二次電子像）を示す図である。It is a figure which shows the SEM photograph (secondary electron image) of the powder (AHZL560F) after an etching process in the 1st process of the manufacturing method of this invention. 実施例２及び比較例２のアルミニウム電解コンデンサ用電極材の、焼結後の皮膜の細孔径の測定結果を示す図である。縦軸は、細孔容積（Log Differential Intrusion(mL/g)）を示し、横軸は、細孔径(Pore size Diameter(μm))を示す。FIG. 5 is a diagram showing measurement results of pore diameters of a film after sintering of the electrode materials for aluminum electrolytic capacitors of Example 2 and Comparative Example 2. The vertical axis represents the pore volume (Log Differential Intrusion (mL / g)), and the horizontal axis represents the pore size (Pore size Diameter (μm)). 比較例２及び比較例１４のアルミニウム電解コンデンサ用電極材の、焼結後の皮膜の細孔径の測定結果を示す図である。縦軸は、細孔容積（Log Differential Intrusion(mL/g)）を示し、横軸は、細孔径(Pore size Diameter(μm))を示す。It is a figure which shows the measurement result of the pore diameter of the film after sintering of the electrode material for aluminum electrolytic capacitors of the comparative example 2 and the comparative example 14. The vertical axis represents the pore volume (Log Differential Intrusion (mL / g)), and the horizontal axis represents the pore size (Pore size Diameter (μm)).
　本発明のアルミニウム電解コンデンサ用電極材の製造方法は、（１）アルミニウム及びアルミニウム合金の少なくとも１種の粉末にエッチング処理を施す第１工程、（２）前記粉末、バインダ樹脂及び溶剤を含むペースト組成物からなる皮膜を基材の少なくとも一方の面に形成する第２工程、及び（３）前記皮膜を焼結する第３工程を含む。以下、工程ごとに説明する。 The method for producing an electrode material for an aluminum electrolytic capacitor of the present invention comprises (1) a first step of subjecting at least one powder of aluminum and an aluminum alloy to an etching treatment, and (2) a paste composition containing the powder, a binder resin and a solvent. It includes a second step of forming a film made of a material on at least one surface of the base material, and (3) a third step of sintering the film. Hereinafter, each step will be described.
　（第１工程）
　第１工程は、アルミニウム及びアルミニウム合金の少なくとも１種の粉末にエッチング処理を施す工程である。 (First step)
The first step is a step of etching at least one kind of powder of aluminum and aluminum alloy.
　原料のアルミニウム粉末としては、例えば、アルミニウム純度９９．８重量％以上のアルミニウム粉末が好ましく、より好ましくは９９．９重量％以上である。また、原料のアルミニウム合金粉末としては、例えば、珪素（Ｓｉ）、鉄（Ｆｅ）、銅（Ｃｕ）、マンガン（Ｍｎ）、マグネシウム（Ｍｇ）、クロム（Ｃｒ）、亜鉛（Ｚｎ）、チタン（Ｔｉ）、バナジウム（Ｖ）、ガリウム（Ｇａ）、ニッケル（Ｎｉ）、ホウ素（Ｂ）及びジルコニウム（Ｚｒ）等の元素の１種又は２種以上を含む合金が好ましい。アルミニウム合金中のこれらの元素の含有量は、それぞれ１００重量ｐｐｍ以下、特に５０重量ｐｐｍ以下とすることが好ましい。 As the raw material aluminum powder, for example, an aluminum powder having an aluminum purity of 99.8% by weight or more is preferable, and more preferably 99.9% by weight or more. Examples of the raw material aluminum alloy powder include silicon (Si), iron (Fe), copper (Cu), manganese (Mn), magnesium (Mg), chromium (Cr), zinc (Zn), titanium (Ti). ), Vanadium (V), gallium (Ga), nickel (Ni), boron (B), and zirconium (Zr). The content of these elements in the aluminum alloy is preferably 100 ppm by weight or less, and particularly preferably 50 ppm by weight or less.
　前記粉末としては、焼結前の平均粒径Ｄ５０が１～１５μｍのものを用いることが好ましく、より好ましくは１．８～１５μｍである。特に前記粉末の平均粒径Ｄ５０が３～９μｍの場合には、中高容量のアルミニウム電解コンデンサの電極材として好適に利用することができる。 As the powder, one having an average particle diameter D 50 before sintering of 1 to 15 μm is preferably used, and more preferably 1.8 to 15 μm. In particular, when the powder has an average particle diameter D 50 of 3 to 9 μm, it can be suitably used as an electrode material for a medium-high capacity aluminum electrolytic capacitor.
　なお、本明細書における平均粒径Ｄ５０は、レーザー回折法により粒径とその粒径に該当する粒子の数を求めて得られる粒度分布曲線において全粒子数の５０％目に該当する粒子の粒子径である。また、焼結後の前記粉末の平均粒径Ｄ５０は、前記焼結体の断面を、走査型電子顕微鏡によって観察することによって測定する。例えば、焼結後の前記粉末は、一部が溶融又は粉末同士が繋がった状態となっているが、略円形状を有する部分は近似的に粒子とみなせる。即ち、上記観察において、略円形状を有する粒子のそれぞれの最大径（長径）をその粒子の粒子径とし、任意の５０個の粒子の粒子径を測定し、これらの算術平均を焼結後の前記粉末の平均粒子径とする。かかる方法により得られる粉末の粒子径は、焼結前の粒子径と比較して、殆ど変化しない。 In addition, the average particle diameter D 50 in the present specification is the particle diameter corresponding to 50% of all particles in the particle size distribution curve obtained by obtaining the particle diameter and the number of particles corresponding to the particle diameter by the laser diffraction method. The particle size. The average particle diameter D 50 of the powder after sintering is measured by observing the cross section of the sintered body with a scanning electron microscope. For example, although part of the powder after sintering is in a molten state or powders are connected to each other, a part having a substantially circular shape can be approximately regarded as a particle. That is, in the above observation, the maximum diameter (major axis) of each particle having a substantially circular shape is taken as the particle diameter of the particle, the particle diameter of any 50 particles is measured, and the arithmetic mean of these is calculated after sintering. The average particle diameter of the powder is used. The particle size of the powder obtained by such a method hardly changes as compared with the particle size before sintering.
　前記粉末の形状は、特に限定されないが、球状、略球状、不定形状のいずれかを好適に使用できる。前記粉末の形状は、球状、略球状が好ましい。粉末の形状が球状、略球状であることにより、鱗片状又は繊維状等の形状である場合に生じる可能性がある、エッチング処理の際の薄い部分または細い部分による分断が、より一層抑制される。 The shape of the powder is not particularly limited, but a spherical shape, a substantially spherical shape, or an irregular shape can be preferably used. The shape of the powder is preferably spherical or substantially spherical. Due to the fact that the powder has a spherical shape or a substantially spherical shape, the division by the thin portion or the thin portion during the etching treatment, which may occur in the case of a scale-like or fibrous shape, is further suppressed. .
　前記粉末は、公知の方法によって製造されるものを使用することができる。例えば、アトマイズ法、メルトスピニング法、回転円盤法、回転電極法、急冷凝固法等が挙げられるが、工業的生産にはアトマイズ法、特にガスアトマイズ法が好ましい。即ち、溶湯をアトマイズすることにより得られる粉末を用いることが望ましい。 As the powder, one manufactured by a known method can be used. For example, the atomizing method, melt spinning method, rotating disk method, rotating electrode method, rapid solidification method and the like can be mentioned, but the atomizing method, particularly the gas atomizing method is preferable for industrial production. That is, it is desirable to use the powder obtained by atomizing the molten metal.
　エッチング処理は特に限定されないが、酸性溶液またはアルカリ性溶液による化学エッチングであることが好ましい。特に酸性溶液による化学エッチングであると、効果的に表面積を拡大でき、さらに分散性が良く第２工程におけるペースト組成物をより一層容易に混合することができる。アルカリ性溶液による化学エッチングである場合、表面積をより一層効果的に拡大できるが、前記粉末が凝集し易くなるおそれがある。 The etching treatment is not particularly limited, but chemical etching with an acidic solution or an alkaline solution is preferable. Particularly, in the case of chemical etching using an acidic solution, the surface area can be effectively expanded, and the dispersibility is good, and the paste composition in the second step can be mixed more easily. In the case of chemical etching using an alkaline solution, the surface area can be expanded more effectively, but the powder may easily aggregate.
　これらのエッチング処理を施すことにより、前記粉末に細孔を形成し表面積をより一層増大させることができる。前記粉末に形成される細孔の細孔径は１．３μｍ以下が好ましく、１．１μｍ以下がより好ましい。粉末の細孔径の上限が上記範囲である粉末を用いると、得られるコンデンサ用電極材の表面積をより一層増大させることができ、容量および体積あたりの容量がより一層高いアルミニウム電解コンデンサ用電極材を得ることができる。また、前記粉末に形成される細孔の細孔径は０．３μｍ以上が好ましく、０．６μｍ以上がより好ましい。粉末の細孔径の下限が上記範囲である粉末を用いると、得られるコンデンサ用電極材の静電容量がより一層向上する。 By performing these etching treatments, it is possible to form pores in the powder and further increase the surface area. The pore diameter of the pores formed in the powder is preferably 1.3 μm or less, more preferably 1.1 μm or less. By using a powder having an upper limit of the pore diameter of the powder in the above range, the surface area of the obtained capacitor electrode material can be further increased, and the capacity and the capacity per volume of the aluminum electrolytic capacitor electrode material can be further increased. Obtainable. The pore size of the pores formed in the powder is preferably 0.3 μm or more, more preferably 0.6 μm or more. When the powder having the lower limit of the pore diameter of the powder is within the above range, the capacitance of the obtained capacitor electrode material is further improved.
　上記酸性溶液による化学エッチングに用いる酸性溶液としては特に限定されず、塩酸、硫酸、燐酸、硝酸等の１または２以上を含有する混酸水溶液等の公知の酸性溶液を用いることができる。酸性溶液の濃度は、低電圧領域で高い容量を示すアルミニウム電解コンデンサ用電極材、高電圧領域で高い容量を示すアルミニウム電解コンデンサ用電極材、又はその両方の領域で高い容量を示すアルミニウム電解コンデンサ用電極材等、所望の特性に応じて適宜設定すればよいが、１０～４０質量％が好ましい。また、エッチング温度及び時間も、粉末の形状や平均粒径、エッチングにより粉末に形成しようとする細孔径、細孔の数、分布、表面積等に応じて適宜調整すればよいが、２０～９０℃で１～２１０分程度が好ましい。 The acidic solution used for the chemical etching with the above acidic solution is not particularly limited, and a known acidic solution such as a mixed acid aqueous solution containing one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid and the like can be used. The concentration of the acidic solution is for aluminum electrolytic capacitor electrode material that shows high capacity in the low voltage region, aluminum electrolytic capacitor electrode material that shows high capacity in the high voltage region, or aluminum electrolytic capacitor that shows high capacity in both regions. The electrode material and the like may be appropriately set according to desired characteristics, but 10 to 40 mass% is preferable. Further, the etching temperature and time may be appropriately adjusted depending on the shape and average particle diameter of the powder, the pore diameter to be formed in the powder by etching, the number of pores, the distribution, the surface area, etc. It is preferably 1 to 210 minutes.
　上記アルカリ性溶液による化学エッチングに用いるアルカリ性溶液は、特に限定されず、例えば、苛性ソーダ等のアルカリ性溶液（水溶液）を用いることができる。アルカリ性溶液の濃度は、低電圧領域で高い容量を示すアルミニウム電解コンデンサ用電極材、高電圧領域で高い容量を示すアルミニウム電解コンデンサ用電極材、又はその両方の領域で高い容量を示すアルミニウム電解コンデンサ用電極材等、所望の特性を示す電極材に応じて適宜設定すればよいが、通常１０～４０質量％程度が好ましい。また、エッチング温度及び時間も、粉末の形状や平均粒径、エッチングにより粉末に形成しようとする細孔径、細孔の数、分布、表面積等に応じて適宜調整すればよいが、通常は温度２０～９０℃で１～２１０分程度が好ましい。 The alkaline solution used for the chemical etching with the above alkaline solution is not particularly limited, and for example, an alkaline solution (aqueous solution) such as caustic soda can be used. The concentration of the alkaline solution is for aluminum electrolytic capacitor electrode material that shows high capacity in the low voltage region, aluminum electrolytic capacitor electrode material that shows high capacity in the high voltage region, or for aluminum electrolytic capacitor that shows high capacity in both regions. It may be appropriately set according to an electrode material such as an electrode material exhibiting desired characteristics, but usually about 10 to 40 mass% is preferable. Further, the etching temperature and time may be appropriately adjusted according to the shape and average particle size of the powder, the pore size to be formed in the powder by etching, the number of pores, the distribution, the surface area, etc. It is preferably about 1 to 210 minutes at about 90 ° C.
　上記エッチング処理を行うことにより、所望の特性を示す電極材を得ることができる。例えば、酸性溶液またはアルカリ性溶液による化学エッチングを施すことにより、例えば２５０～５５０Ｖ程度の高電圧領域で高い容量および体積あたりの容量を示す電極材を得ることができる。その理由としては、以下のように考えられる。 By performing the above etching treatment, an electrode material having desired characteristics can be obtained. For example, by performing chemical etching with an acidic solution or an alkaline solution, it is possible to obtain an electrode material having a high capacity and a capacity per volume in a high voltage region of, for example, about 250 to 550V. The reason is considered as follows.
　即ち、アルカリ性溶液による化学エッチングは、アルミニウムの表面、酸化皮膜を溶解させる能力が高く、電極材のアルミニウム粉末の平均粒径Ｄ５０を低下させる事ができ、電極材の表面積を向上させるからであると考えられる。また、酸性溶液による化学エッチングは電極材のアルミニウム表面を溶解させ、同時にアルミニウム粉末へのトンネル状のエッチングピットも形成するからであると考えられる。 That is, the chemical etching with the alkaline solution has a high ability to dissolve the surface of aluminum and the oxide film, can reduce the average particle diameter D 50 of the aluminum powder of the electrode material, and improves the surface area of the electrode material. it is conceivable that. It is also considered that the chemical etching with the acidic solution dissolves the aluminum surface of the electrode material and simultaneously forms tunnel-shaped etching pits into the aluminum powder.
　エッチング処理の後に、上記粉末に、更に、洗浄を施すことが好ましい。洗浄液は特に限定されないが、例えば、水、エタノール、トルエン、ケトン類、エステル類等の有機溶剤の単体または混合液を使用することができる。コストの観点から水で洗浄を行うことが好ましい。また、洗浄液には、必要に応じて界面活性剤や中和剤などの添加剤を加えてもよい。洗浄の回数は特に限定されないが複数回行うことが好ましい。また、洗浄を複数回行う場合、途中で洗浄液を変更してもよい。洗浄を行うことにより、上記酸性溶液、上記アルカリ性溶液、又は、粉末と溶液の反応生成物等が、粉末の表面に残留することによるアルミニウム電解コンデンサ用電極材の特性の低下をより一層抑制することができる。 After the etching treatment, it is preferable to further wash the above powder. The cleaning liquid is not particularly limited, but, for example, a simple substance or a mixed liquid of organic solvents such as water, ethanol, toluene, ketones and esters can be used. It is preferable to wash with water from the viewpoint of cost. Moreover, you may add additives, such as a surfactant and a neutralizer, to a washing | cleaning liquid as needed. The number of times of washing is not particularly limited, but it is preferably performed plural times. Further, when cleaning is performed a plurality of times, the cleaning liquid may be changed during the cleaning. By performing the washing, the acidic solution, the alkaline solution, or the reaction product of the powder and the solution, etc. can further suppress the deterioration of the characteristics of the electrode material for the aluminum electrolytic capacitor due to remaining on the surface of the powder. You can
　本発明の製造方法は、上記第１工程において、上記粉末に洗浄を施した後に、更に、粉末を乾燥させることが好ましい。 In the production method of the present invention, it is preferable that the powder is further dried after the powder is washed in the first step.
　以上説明した第１工程により、アルミニウム及びアルミニウム合金の少なくとも１種の粉末にエッチング処理が施される。 By the first step described above, at least one kind of powder of aluminum and aluminum alloy is subjected to etching treatment.
　（第２工程）
　第２工程は、上記粉末、バインダ樹脂及び溶剤を含むペースト組成物からなる皮膜を基材の少なくとも一方の面に形成する工程である。 (Second step)
The second step is a step of forming a film made of the paste composition containing the powder, the binder resin and the solvent on at least one surface of the base material.
　上記ペースト組成物は、上記粉末の他に、バインダ樹脂及び溶剤を含む。これらはいずれも、公知又は市販のものを使用することができる。 The above paste composition contains a binder resin and a solvent in addition to the above powder. Any of these may be publicly known or commercially available.
　上記バインダ樹脂は限定的でなく、例えば、カルボキシ変性ポリオレフィン樹脂、酢酸ビニル樹脂、塩化ビニル樹脂、塩酢ビ共重合樹脂、ビニルアルコール樹脂、ブチラール樹脂、フッ化ビニル樹脂、アクリル樹脂、ポリエステル樹脂、ウレタン樹脂、エポキシ樹脂、尿素樹脂、フェノール樹脂、アクリロニトリル樹脂、セルロース樹脂、パラフィンワックス、ポリエチレンワックス等の合成樹脂又はワックス、タール、にかわ、ウルシ、松脂、ミツロウ等の天然樹脂又はワックスが好適に使用できる。これらのバインダ樹脂は、分子量、樹脂の種類等により、加熱時に揮発するものと、熱分解によりその残渣がアルミニウム粉末とともに残存するものとがあり、所望の静電特性等に応じて使い分けることができる。 The binder resin is not limited, for example, carboxy-modified polyolefin resin, vinyl acetate resin, vinyl chloride resin, vinyl chloride vinyl chloride resin, vinyl alcohol resin, butyral resin, vinyl fluoride resin, acrylic resin, polyester resin, urethane Resins, epoxy resins, urea resins, phenol resins, acrylonitrile resins, cellulose resins, paraffin wax, polyethylene wax, and other synthetic resins or waxes, tars, glues, lacquers, pine resin, beeswax, and other natural resins or waxes can be preferably used. These binder resins include those that volatilize during heating and those that remain with aluminum powder due to thermal decomposition, depending on the molecular weight, type of resin, etc., and can be used properly according to the desired electrostatic characteristics and the like. .
　上記溶剤は、公知のものが使用できる。例えば、水のほか、エタノール、トルエン、ケトン類、エステル類等の有機溶剤を使用することができる。 Known solvents can be used as the above solvent. For example, in addition to water, organic solvents such as ethanol, toluene, ketones and esters can be used.
　上記ペースト組成物は、必要に応じて焼結助剤、界面活性剤等の他の成分が含まれていてもよい。これらはいずれも公知又は市販のものを使用することができる。ペースト組成物が上記他の成分を含有することにより、より一層効率よく皮膜を形成することができる。 The above paste composition may optionally contain other components such as a sintering aid and a surfactant. Any of these may be publicly known or commercially available. By containing the above-mentioned other components in the paste composition, the film can be formed more efficiently.
　第２工程では、上記ペースト組成物を基材の少なくとも一方の面に塗布することにより、皮膜を形成する。基材としては、アルミニウム電解コンデンサ用電極材の基材として使用されるものであれば、公知のものを広く使用できる。特にアルミニウム箔を好適に用いることができる。 In the second step, a film is formed by applying the paste composition on at least one surface of the base material. As the base material, known materials can be widely used as long as they are used as the base material of the electrode material for aluminum electrolytic capacitors. Particularly, aluminum foil can be preferably used.
　基材としてのアルミニウム箔は、特に限定されず、例えば、純アルミニウム又はアルミニウム合金を用いることができる。本発明で用いられるアルミニウム箔は、その組成として、珪素（Ｓｉ）、鉄（Ｆｅ）、銅（Ｃｕ）、マンガン（Ｍｎ）、マグネシウム（Ｍｇ）、クロム（Ｃｒ）、亜鉛（Ｚｎ）、チタン（Ｔｉ）、バナジウム（Ｖ）、ガリウム（Ｇａ）、ニッケル（Ｎｉ）及びホウ素（Ｂ）の少なくとも１種の合金元素を必要範囲内において添加したアルミニウム合金あるいは上記の不可避的不純物元素の含有量を限定したアルミニウムも含む。アルミニウム箔の純度は９９．８重量％以上が好ましく、より好ましくは９９．９重量％以上である。上記アルミニウム箔の純度は上記アルミニウム粉末の純度と同じでもよいし、異なっていてもよいが、上記アルミニウム箔と上記粉末の間の焼結後の強度を向上させるため異なっているほうが好ましい。 The aluminum foil as the base material is not particularly limited, and for example, pure aluminum or aluminum alloy can be used. The composition of the aluminum foil used in the present invention is silicon (Si), iron (Fe), copper (Cu), manganese (Mn), magnesium (Mg), chromium (Cr), zinc (Zn), titanium ( Ti), vanadium (V), gallium (Ga), nickel (Ni), and boron (B) at least one type of alloying element added within the required range, or the content of the above unavoidable impurity elements is limited. Also includes aluminum. The purity of the aluminum foil is preferably 99.8% by weight or more, more preferably 99.9% by weight or more. The purity of the aluminum foil may be the same as or different from the purity of the aluminum powder, but is preferably different in order to improve the strength after sintering between the aluminum foil and the powder.
　アルミニウム箔の厚みは、特に限定されないが、５μｍ以上１００μｍ以下、特に、１０μｍ以上５０μｍ以下の範囲内とするのが好ましい。 The thickness of the aluminum foil is not particularly limited, but it is preferably in the range of 5 μm or more and 100 μm or less, particularly 10 μm or more and 50 μm or less.
　上記のアルミニウム箔は、公知の方法によって製造されるものを使用することができる。例えば、上記の所定の組成を有するアルミニウム又はアルミニウム合金の溶湯を調製し、これを鋳造して得られた鋳塊を適切に均質化処理する。その後、この鋳塊に熱間圧延と冷間圧延を施すことにより、アルミニウム箔を得ることができる。 As the above aluminum foil, one manufactured by a known method can be used. For example, a molten metal of aluminum or aluminum alloy having the above-mentioned predetermined composition is prepared, and the ingot obtained by casting the molten metal is appropriately homogenized. Then, the aluminum foil can be obtained by subjecting this ingot to hot rolling and cold rolling.
　なお、上記の冷間圧延工程の途中で、５０℃以上５００℃以下、特に１５０℃以上４００℃以下の範囲内で中間焼鈍処理を施してもよい。また、上記の冷間圧延工程の後に、１５０℃以上６５０℃以下、特に３５０℃以上５５０℃以下の範囲内で焼鈍処理を施して軟質箔としてもよい。 Incidentally, intermediate annealing may be performed in the range of 50 ° C. or higher and 500 ° C. or lower, particularly 150 ° C. or higher and 400 ° C. or lower during the cold rolling process. Further, after the cold rolling step, an annealing treatment may be performed within a range of 150 ° C. or higher and 650 ° C. or lower, particularly 350 ° C. or higher and 550 ° C. or lower to obtain a soft foil.
　皮膜は基材の少なくとも一方の面に形成する。第２工程では、皮膜は、基材の両面に形成されることが好ましい。両面に形成する場合には、基材を挟んで皮膜および未形成部を対称に配置することが好ましい。対称に配置することにより、第３工程において、焼結による基材と皮膜との界面での剥離をより一層抑制することができ、皮膜に発生する反りをより一層抑制することができる。 The film is formed on at least one side of the substrate. In the second step, the film is preferably formed on both sides of the base material. When it is formed on both sides, it is preferable to arrange the coating and the unformed portion symmetrically with the base material sandwiched therebetween. By arranging them symmetrically, in the third step, peeling at the interface between the base material and the coating due to sintering can be further suppressed, and warpage that occurs in the coating can be further suppressed.
　第２工程において、皮膜は、基材の全面に形成されていないことが好ましい。すなわち、基材の面に皮膜を形成した状態で、基材の面と垂直な方向から平面視した場合、基材の面積が皮膜の面積よりも広く、基材の面に、皮膜が形成されていない部分が存在することが好ましい。当該構成とすることで、ロールツーロールで処理を行う際のハンドリングがより一層向上する。具体的には、アルミニウム電解コンデンサ用電極材の表面に酸化皮膜を形成する化成処理等の際に基材の破断をより一層抑制することができる。 In the second step, it is preferable that the film is not formed on the entire surface of the base material. That is, when the coating is formed on the surface of the base material, when viewed in a direction perpendicular to the surface of the base material, the area of the base material is larger than the area of the coating, and the coating is formed on the surface of the base material. It is preferable that there is a portion that is not present. With this configuration, handling when performing a roll-to-roll process is further improved. Specifically, it is possible to further suppress breakage of the base material during chemical conversion treatment for forming an oxide film on the surface of the electrode material for an aluminum electrolytic capacitor.
　皮膜の合計厚さは３０～２０００μｍが好ましく、６０～２０００μｍがより好ましい。この皮膜の合計厚さは、圧延・焼結を経て最終的に得られる焼結体の合計厚さが３０～２０００μｍとなるように設定することが好ましい。これらの数値は、基材の片面又は両面に形成するどちらの場合にも当てはまるが、両面に形成する場合には、片面の被膜の厚さは全体厚み（基材の厚さも含む）の１／３以上であることが好ましい。 The total thickness of the film is preferably 30 to 2000 μm, more preferably 60 to 2000 μm. The total thickness of this film is preferably set so that the total thickness of the sintered body finally obtained through rolling and sintering is 30 to 2000 μm. These values apply to both cases of forming on one side or both sides of the substrate, but when forming on both sides, the thickness of the coating on one side is 1 / th of the total thickness (including the thickness of the substrate). It is preferably 3 or more.
　なお、上記皮膜の平均厚みは、マイクロメーターで７点測定し、最大値と最小値を除いた５点の平均値である。 Note that the average thickness of the above film is the average value of 5 points obtained by measuring 7 points with a micrometer and excluding the maximum and minimum values.
　皮膜は、必要に応じて、２０～３００℃の範囲内の温度で乾燥させてもよい。 The coating may be dried at a temperature within the range of 20 to 300 ° C., if necessary.
　皮膜の形成方法は特に限定されず、従来公知の方法を採用することができる。例えば、ペースト組成物をローラー、刷毛、スプレー、ディッピング等の塗布方法を用いて皮膜形成してもよいし、シルクスクリーン印刷やダイコート等の公知の印刷方法により形成してもよい。 The method for forming the film is not particularly limited, and a conventionally known method can be adopted. For example, the paste composition may be formed into a film by using a coating method such as roller, brush, spray, dipping, or may be formed by a known printing method such as silk screen printing or die coating.
　以上説明した第２工程により、アルミニウム及びアルミニウム合金の少なくとも１種の粉末、バインダ樹脂及び溶剤を含むペースト組成物からなる皮膜が基材の少なくとも一方の面に形成される。 By the second step described above, a film made of a paste composition containing at least one powder of aluminum and aluminum alloy, a binder resin and a solvent is formed on at least one surface of the base material.
（第３工程）
　第３工程は、前記皮膜を焼結する工程である。 (3rd step)
The third step is a step of sintering the film.
　焼結温度は、５６０～６６０℃が好ましく、５７０～６５０℃がより好ましく、５８０～６２０℃が更に好ましい。焼結時間は、焼結温度等により異なるが、通常は５～２４時間程度の範囲内で適宜決定することができる。 The sintering temperature is preferably 560 to 660 ° C, more preferably 570 to 650 ° C, even more preferably 580 to 620 ° C. Although the sintering time varies depending on the sintering temperature and the like, it can be appropriately determined usually within the range of about 5 to 24 hours.
　焼結雰囲気は特に限定されず、例えば真空雰囲気、不活性ガス雰囲気、酸化性ガス雰囲気（大気）、還元性雰囲気等のいずれであってもよいが、特に真空雰囲気又は還元性雰囲気とすることが好ましい。また、圧力条件についても、常圧、減圧又は加圧のいずれでもよい。 The sintering atmosphere is not particularly limited and may be, for example, a vacuum atmosphere, an inert gas atmosphere, an oxidizing gas atmosphere (atmosphere), a reducing atmosphere, or the like, but a vacuum atmosphere or a reducing atmosphere is particularly preferable. preferable. The pressure condition may be normal pressure, reduced pressure or increased pressure.
　本発明の製造方法では、第３工程により皮膜が焼結され、更に、基材と焼結後の皮膜とが接合されることが好ましい。焼結により基材と焼結後の皮膜とが接合される構成とすることにより、アルミニウム電解コンデンサ用電極材を、より一層容易に製造することができる。このような構成としては、例えば、基材としてアルミニウム箔を用い、第２工程によりアルミニウム箔の少なくとも一方の面に形成皮膜を形成し、第３工程により皮膜が焼結され、焼結後の皮膜とアルミニウム箔とが接合される構成が挙げられる。 In the manufacturing method of the present invention, it is preferable that the film is sintered in the third step, and that the base material and the film after sintering are joined together. With the configuration in which the base material and the film after sintering are joined by sintering, the electrode material for an aluminum electrolytic capacitor can be manufactured more easily. As such a structure, for example, an aluminum foil is used as a base material, a forming film is formed on at least one surface of the aluminum foil in the second step, the film is sintered in the third step, and the film after sintering is formed. And the aluminum foil is joined.
　なお、本発明の製造方法では、第２工程後第３工程に先立って、予め１００℃以上から６００℃以下の温度範囲で保持時間が５時間以上の加熱処理（脱脂処理）を行なうことが好ましい。加熱処理雰囲気は特に限定されず、例えば真空雰囲気、不活性ガス雰囲気又は酸化性ガス雰囲気中のいずれでもよい。また、圧力条件も、常圧、減圧又は加圧のいずれでもよい。 In the manufacturing method of the present invention, it is preferable that a heat treatment (degreasing treatment) with a holding time of 5 hours or longer is performed in advance in a temperature range of 100 ° C. or higher and 600 ° C. or lower in advance of the third step after the second step. . The heat treatment atmosphere is not particularly limited, and may be, for example, a vacuum atmosphere, an inert gas atmosphere, or an oxidizing gas atmosphere. The pressure condition may be normal pressure, reduced pressure or increased pressure.
　以上説明した第３工程により、基材の少なくとも一方の面に形成された皮膜が焼結される。 By the third step described above, the film formed on at least one surface of the base material is sintered.
　本発明の製造方法により、アルミニウム電解コンデンサ用電極材が製造される。本発明の製造方法により製造されるアルミニウム電解コンデンサ用電極材は、体積あたりの静電容量が大きいので、当該電極材を用いて製造されるコンデンサを小型化することが可能となる。また、焼結した皮膜が厚く形成されているので、電極としての静電容量が大きいアルミニウム電解コンデンサ用電極材となり、当該電極材を用いて製造されるコンデンサを大容量化することが可能となる。 An electrode material for an aluminum electrolytic capacitor is manufactured by the manufacturing method of the present invention. Since the aluminum electrolytic capacitor electrode material manufactured by the manufacturing method of the present invention has a large capacitance per volume, it is possible to downsize a capacitor manufactured using the electrode material. Further, since the sintered film is formed thick, it becomes an electrode material for an aluminum electrolytic capacitor having a large electrostatic capacitance as an electrode, and it becomes possible to increase the capacity of a capacitor manufactured using the electrode material. .
　上記第３工程により焼結された、焼結後の皮膜の細孔径、すなわち、本発明の製造方法により製造されるアルミニウム電解コンデンサ用電極材の、焼結後の皮膜の細孔径は１．３μｍ以下が好ましく、１．１μｍ以下がより好ましい。焼結後の皮膜の細孔径の上限が上記範囲であると、本発明の製造方法により製造されるコンデンサ用電極材の表面積をより一層増大させることができ、容量および体積あたりの容量がより一層高いアルミニウム電解コンデンサ用電極材となる。また、前記焼結後の皮膜の細孔径は０．３μｍ以上が好ましく、０．６μｍ以上がより好ましい。焼結後の皮膜の細孔径の下限が上記範囲であると、得られるコンデンサ用電極材の静電容量がより一層向上する。 The pore size of the sintered film sintered in the third step, that is, the pore size of the sintered film of the electrode material for an aluminum electrolytic capacitor manufactured by the manufacturing method of the present invention is 1.3 μm. The following is preferable, and 1.1 μm or less is more preferable. When the upper limit of the pore diameter of the film after sintering is in the above range, the surface area of the capacitor electrode material manufactured by the manufacturing method of the present invention can be further increased, and the capacity and the capacity per volume can be further increased. It becomes a high electrode material for aluminum electrolytic capacitors. The pore size of the film after sintering is preferably 0.3 μm or more, more preferably 0.6 μm or more. When the lower limit of the pore diameter of the film after sintering is in the above range, the capacitance of the obtained capacitor electrode material is further improved.
　なお、アルミニウム電解コンデンサ用電極材の焼結後の皮膜の細孔径は一例としては水銀圧入法で測定される。なお、ガス吸着法といった他の測定方法についても排除するものではなく、細孔径に応じて適した測定方法が選択される。通常、細孔径は分布を有しているが、細孔容積の大きいピークの細孔径を、測定対象における細孔径として採用する。細孔容積のピークが複数ある場合は、例えば電子顕微鏡観察等で測定した細孔径に最も近い細孔径を採用する。 Note that the pore size of the film after sintering of the electrode material for aluminum electrolytic capacitors is measured by the mercury injection method as an example. Note that other measuring methods such as the gas adsorption method are not excluded, and an appropriate measuring method is selected according to the pore size. Usually, the pore diameter has a distribution, but the pore diameter of the peak with a large pore volume is adopted as the pore diameter in the measurement target. When there are a plurality of pore volume peaks, the pore diameter closest to the pore diameter measured by electron microscope observation or the like is adopted.
　以下、実施例及び比較例を示し、本発明を具体的に説明する。但し、本発明は実施例に限定されない。 Hereinafter, the present invention will be specifically described by showing Examples and Comparative Examples. However, the present invention is not limited to the examples.
　下記手順に従って実施例及び比較例の電極材を作製した。得られた電極材の静電容量を下記測定方法により測定した。 The electrode materials of Examples and Comparative Examples were manufactured according to the following procedure. The capacitance of the obtained electrode material was measured by the following measuring method.
（静電容量）
　ホウ酸水溶液（５０ｇ／Ｌ）中で電極材に対し２５０、５５０及び７００Ｖの各電圧で化成処理を施した後、ホウ酸アンモニウム水溶液（３ｇ／Ｌ）にて静電容量を測定した。測定投影面積は１０ｃｍ２とした。 (Capacitance)
After subjecting the electrode material to chemical conversion treatment in an aqueous boric acid solution (50 g / L) at voltages of 250, 550 and 700 V, the capacitance was measured with an ammonium borate aqueous solution (3 g / L). The measured projected area was 10 cm 2 .
（細孔径）
　電極材の焼結後の皮膜の細孔径を、細孔分布測定装置（Micromeritics社製　AutoPoreIV 9500）を用いて測定した。得られた測定結果のうち、最も細孔容積（Log Differential Intrusion(mL/g)）の大きいピークの細孔径(Pore size Diameter(μm))を電極材の焼結後の皮膜の細孔径とした。 (Pore size)
The pore diameter of the film after sintering of the electrode material was measured using a pore distribution measuring device (AutoPore IV 9500 manufactured by Micromeritics). Among the obtained measurement results, the pore diameter (Pore size Diameter (μm)) of the peak with the largest pore volume (Log Differential Intrusion (mL / g)) was taken as the pore diameter of the film after sintering of the electrode material. .
＜実施例及び比較例＞             
比較例１
　平均粒径Ｄ５０が１５．０μｍのアルミニウム粉末（ＪＩＳ　Ａ１０８０、東洋アルミニウム（株）製、ＡＨＺＬ５３０Ｃ）とエチルセルロース系バインダー樹脂と溶剤（酢酸ブチル）を混合しペースト組成物を得た。この組成物を、厚みが３０μｍのアルミニウム箔基材（ＳＢ材　純度９９．９９重量％）の両面に対称に、焼結後の皮膜の厚みがそれぞれ５０μｍになるようにコンマコーターを用いて塗工し、皮膜を空気雰囲気で１００℃で１．５分間乾燥した。このアルミニウム箔をアルゴンガス雰囲気中にて温度６００℃で１０時間焼結することにより、比較例１の電極材を作製した。焼結後の電極材の厚みは約１２０μｍであった。 <Examples and Comparative Examples>
Comparative Example 1
An aluminum powder having an average particle diameter D 50 of 15.0 μm (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHZL530C) was mixed with an ethylcellulose-based binder resin and a solvent (butyl acetate) to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity 99.99% by weight) having a thickness of 30 μm using a comma coater so that the thickness of the film after sintering was 50 μm. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 μm.
　尚、アルミニウム粉末の平均粒径は、マイクロトラックMT3300EXII（日機装株式会社製）を使用し、レーザー解析法により粒度分布を体積基準で測定し、平均粒径Ｄ５０を算出した。 The average particle size of the aluminum powder was obtained by using Microtrac MT3300EXII (manufactured by Nikkiso Co., Ltd.) and measuring the particle size distribution on a volume basis by a laser analysis method to calculate an average particle size D 50 .
比較例２
　平均粒径Ｄ５０が９．０μｍのアルミニウム粉末（ＪＩＳ　Ａ１０８０、東洋アルミニウム（株）製、ＡＨＺＬ５６０Ｆ）とエチルセルロース系バインダー樹脂と溶剤（酢酸ブチル）を混合しペースト組成物を得た。この組成物を、厚みが３０μｍのアルミニウム箔基材（ＳＢ材　純度９９．９９重量％）の両面に対称に、焼結後の皮膜の厚みがそれぞれ５０μｍになるようにコンマコーターを用いて塗工し、皮膜を空気雰囲気で１００℃で１．５分間乾燥した。このアルミニウム箔をアルゴンガス雰囲気中にて温度６００℃で１０時間焼結することにより、比較例１の電極材を作製した。焼結後の電極材の厚みは約１２０μｍであった。 Comparative example 2
An aluminum powder having an average particle size D 50 of 9.0 μm (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHZL560F), an ethylcellulose-based binder resin, and a solvent (butyl acetate) were mixed to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity of 99.99% by weight) having a thickness of 30 μm using a comma coater so that the thickness of the film after sintering was 50 μm. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 μm.
比較例３
　平均粒径Ｄ５０が３．０μｍのアルミニウム粉末（ＪＩＳ　Ａ１０８０、東洋アルミニウム（株）製、ＡＨＺＬ５８ＦＮ）とエチルセルロース系バインダー樹脂と溶剤（酢酸ブチル）を混合しペースト組成物を得た。この組成物を、厚みが３０μｍのアルミニウム箔基材（ＳＢ材　純度９９．９９重量％）の両面に対称に、焼結後の皮膜の厚みがそれぞれ５０μｍになるようにコンマコーターを用いて塗工し、皮膜を空気雰囲気で１００℃で１．５分間乾燥した。このアルミニウム箔をアルゴンガス雰囲気中にて温度６００℃で１０時間焼結することにより、比較例１の電極材を作製した。焼結後の電極材の厚みは約１２０μｍであった。 Comparative Example 3
An aluminum powder having an average particle diameter D 50 of 3.0 μm (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHZL58FN) was mixed with an ethylcellulose-based binder resin and a solvent (butyl acetate) to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity 99.99% by weight) having a thickness of 30 μm using a comma coater so that the thickness of the film after sintering was 50 μm. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 μm.
比較例４
　平均粒径Ｄ５０が１.８μｍのアルミニウム粉末（ＪＩＳ　Ａ１０８０、東洋アルミニウム（株）製、ＡＨＵ０９１）とエチルセルロース系バインダー樹脂と溶剤（酢酸ブチル）を混合しペースト組成物を得た。この組成物を、厚みが３０μｍのアルミニウム箔基材（ＳＢ材　純度９９．９９重量％）の両面に対称に、焼結後の皮膜の厚みがそれぞれ５０μｍになるようにコンマコーターを用いて塗工し、皮膜を空気雰囲気で１００℃で１．５分間乾燥した。このアルミニウム箔をアルゴンガス雰囲気中にて温度６００℃で１０時間焼結することにより、比較例１の電極材を作製した。焼結後の電極材の厚みは約１２０μｍであった。 Comparative Example 4
An aluminum powder (JIS A1080, manufactured by Toyo Aluminum Co., Ltd., AHU091) having an average particle diameter D 50 of 1.8 μm was mixed with an ethylcellulose-based binder resin and a solvent (butyl acetate) to obtain a paste composition. This composition was applied symmetrically on both sides of an aluminum foil base material (SB material, purity of 99.99% by weight) having a thickness of 30 μm using a comma coater so that the thickness of the film after sintering was 50 μm. Then, the film was dried in an air atmosphere at 100 ° C. for 1.5 minutes. The aluminum foil was sintered in an argon gas atmosphere at a temperature of 600 ° C. for 10 hours to prepare an electrode material of Comparative Example 1. The thickness of the electrode material after sintering was about 120 μm.
実施例１
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 1
An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例２
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例２と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 2
An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例３
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例３と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 3
An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例４
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例４と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 4
An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
　結果を表１に示す。 The results are shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
実施例５
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１と同様にして電極材を作成した。
　エッチング液：硫酸（濃度４０％）、温度：２５℃、時間：６０ｍｉｎ Example 5
An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions.
Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
実施例６
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例２と同様にして電極材を作成した。
　エッチング液：硫酸（濃度４０％）、温度：２５℃、時間：６０ｍｉｎ Example 6
An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions.
Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
実施例７
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例３と同様にして電極材を作成した。
　エッチング液：硫酸（濃度４０％）、温度：２５℃、時間：６０ｍｉｎ Example 7
An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions.
Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
実施例８
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例４と同様にして電極材を作成した。
　エッチング液：硫酸（濃度４０％）、温度：２５℃、時間：６０ｍｉｎ Example 8
An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions.
Etching solution: sulfuric acid (concentration 40%), temperature: 25 ° C, time: 60 min
　結果を表２に示す。 The results are shown in Table 2.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
実施例９
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：２５℃、時間：２１０ｍｉｎ Example 9
An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
実施例１０
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例２と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：２５℃、時間：２１０ｍｉｎ Example 10
An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
実施例１１
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例３と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：２５℃、時間：２１０ｍｉｎ Example 11
An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
実施例１２
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例４と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：２５℃、時間：２１０ｍｉｎ Example 12
An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 25 ° C, time: 210 min
　結果を表３に示す。
Figure JPOXMLDOC01-appb-T000003
 The results are shown in Table 3.
Figure JPOXMLDOC01-appb-T000003
実施例１３
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：８０℃、時間：６０ｍｉｎ Example 13
An electrode material was prepared in the same manner as in Comparative Example 1 except that the aluminum powder was subjected to the etching treatment under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
実施例１４
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例２と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：８０℃、時間：６０ｍｉｎ Example 14
An electrode material was prepared in the same manner as in Comparative Example 2 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
実施例１５
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例３と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：８０℃、時間：６０ｍｉｎ Example 15
An electrode material was prepared in the same manner as in Comparative Example 3 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
実施例１６
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例４と同様にして電極材を作成した。
　エッチング液：塩酸（濃度１０％）、温度：８０℃、時間：６０ｍｉｎ Example 16
An electrode material was prepared in the same manner as in Comparative Example 4 except that the aluminum powder was subjected to etching treatment under the following conditions.
Etching solution: hydrochloric acid (concentration 10%), temperature: 80 ° C, time: 60 min
　結果を表４に示す。 The results are shown in Table 4.
Figure JPOXMLDOC01-appb-T000004
Figure JPOXMLDOC01-appb-T000004
比較例５
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ３０μｍになるように塗工すること以外は、比較例１と同様にして電極材を作成した。 Comparative Example 5
An electrode material was prepared in the same manner as in Comparative Example 1 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 30 μm.
比較例６
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ３０μｍになるように塗工すること以外は、比較例２と同様にして電極材を作成した。 Comparative Example 6
An electrode material was prepared in the same manner as in Comparative Example 2 except that the composition was applied symmetrically on both sides of the aluminum foil base material such that the thickness of the film after sintering was 30 μm.
比較例７
　組成物をルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ３０μｍになるように塗工すること以外は、比較例３と同様にして電極材を作成した。 Comparative Example 7
An electrode material was prepared in the same manner as in Comparative Example 3 except that the composition was applied symmetrically on both sides of the aluminum foil base material such that the thickness of the film after sintering was 30 μm.
比較例８
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ３０μｍになるように塗工すること以外は、比較例４と同様にして電極材を作成した。 Comparative Example 8
An electrode material was prepared in the same manner as in Comparative Example 4 except that the composition was applied symmetrically on both sides of the aluminum foil substrate so that the thickness of the film after sintering was 30 μm.
実施例１７
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例５と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 17
An electrode material was prepared in the same manner as in Comparative Example 5 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例１８
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例６と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 18
An electrode material was prepared in the same manner as in Comparative Example 6 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例１９
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例７と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 19
An electrode material was prepared in the same manner as in Comparative Example 7 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例２０
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例８と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 20
An electrode material was prepared in the same manner as in Comparative Example 8 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
　結果を表５に示す。
Figure JPOXMLDOC01-appb-T000005
 Table 5 shows the results.
Figure JPOXMLDOC01-appb-T000005
比較例９
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ１０００μｍになるように塗工すること以外は、比較例１と同様にして電極材を作成した。 Comparative Example 9
An electrode material was prepared in the same manner as in Comparative Example 1 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 μm.
比較例１０
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ１０００μｍになるように塗工すること以外は、比較例２と同様にして電極材を作成した。 Comparative Example 10
An electrode material was prepared in the same manner as in Comparative Example 2 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 μm.
比較例１１
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ１０００μｍになるように塗工すること以外は、比較例３と同様にして電極材を作成した。 Comparative Example 11
An electrode material was prepared in the same manner as in Comparative Example 3 except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 μm.
比較例１２
　組成物をアルミニウム箔基材の両面に対称に、焼結後の皮膜の厚みがそれぞれ１０００μｍになるように塗工すること以外は、比較例４と同様にして電極材を作成した。 Comparative Example 12
An electrode material was prepared in the same manner as in Comparative Example 4, except that the composition was applied symmetrically on both sides of the aluminum foil base material so that the thickness of the film after sintering was 1000 μm.
実施例１７
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例９と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 17
An electrode material was prepared in the same manner as in Comparative Example 9 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例１８
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１０と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 18
An electrode material was prepared in the same manner as in Comparative Example 10 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例１９
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１１と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 19
An electrode material was prepared in the same manner as in Comparative Example 11 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
実施例２０
　アルミニウム粉末に下記の条件でエッチング処理を行うこと以外は、比較例１２と同様にして電極材を作成した。
　エッチング液：塩酸（濃度３０％）、温度：２５℃、時間：６０ｍｉｎ Example 20
An electrode material was prepared in the same manner as in Comparative Example 12 except that the aluminum powder was etched under the following conditions.
Etching solution: hydrochloric acid (concentration 30%), temperature: 25 ° C, time: 60 min
　結果を表６に示す。
Figure JPOXMLDOC01-appb-T000006
 The results are shown in Table 6.
Figure JPOXMLDOC01-appb-T000006
比較例１３（特開２０１４－１３８１５９号公報の実施例１）
　焼結後の電極材に下記の条件でエッチング処理を行うこと以外は、比較例３と同様にして電極材を作成した。
　エッチング液：塩酸及び硫酸の混合液（塩酸濃度：１モル／Ｌ、硫酸濃度：３モル／Ｌ、濃度１５％）、温度：４０℃、時間：２ｍｉｎ Comparative Example 13 (Example 1 of JP-A-2014-138159)
An electrode material was prepared in the same manner as in Comparative Example 3 except that the electrode material after sintering was subjected to etching treatment under the following conditions.
Etching solution: mixed solution of hydrochloric acid and sulfuric acid (hydrochloric acid concentration: 1 mol / L, sulfuric acid concentration: 3 mol / L, concentration 15%), temperature: 40 ° C., time: 2 min
　結果を表７に示す。
Figure JPOXMLDOC01-appb-T000007
 Table 7 shows the results.
Figure JPOXMLDOC01-appb-T000007
比較例１４（特開２０１４－１３８１５９号公報の実施例９）
　焼結後の電極材に下記の条件でエッチング処理を行うこと以外は、比較例２と同様にして電極材を作成した。
　エッチング液：塩酸及び硫酸の混合液（塩酸濃度：１モル／Ｌ、硫酸濃度：３モル／Ｌ、濃度１５％）、温度：４０℃、時間：２ｍｉｎ Comparative Example 14 (Example 9 of JP-A-2014-138159)
An electrode material was prepared in the same manner as in Comparative Example 2 except that the electrode material after sintering was subjected to etching treatment under the following conditions.
Etching solution: mixed solution of hydrochloric acid and sulfuric acid (hydrochloric acid concentration: 1 mol / L, sulfuric acid concentration: 3 mol / L, concentration 15%), temperature: 40 ° C., time: 2 min
　結果を表８に示す。
Figure JPOXMLDOC01-appb-T000008
 Table 8 shows the results.
Figure JPOXMLDOC01-appb-T000008
［結果］
　表１～８に示されるように、各実施例の電極材は、対応する比較例の電極材と比べ、コンデンサに要求される優れた静電容量を有することが確認された。 [result]
As shown in Tables 1 to 8, it was confirmed that the electrode material of each example had excellent capacitance required for the capacitor, as compared with the corresponding electrode material of the comparative example.

Claims (7)

  1. 　アルミニウム電解コンデンサ用電極材の製造方法であって、
    （１）アルミニウム及びアルミニウム合金の少なくとも１種の粉末にエッチング処理を施す第１工程、
    （２）前記粉末、バインダ樹脂及び溶剤を含むペースト組成物からなる皮膜を基材の少なくとも一方の面に形成する第２工程、及び
    （３）前記皮膜を焼結する第３工程
    を含むことを特徴とする、アルミニウム電解コンデンサ用電極材の製造方法。     A method of manufacturing an electrode material for an aluminum electrolytic capacitor, comprising:
    (1) A first step of subjecting at least one powder of aluminum and aluminum alloy to an etching treatment,
    (2) A second step of forming a film made of a paste composition containing the powder, a binder resin and a solvent on at least one surface of a substrate, and (3) a third step of sintering the film. A method of manufacturing an electrode material for an aluminum electrolytic capacitor, which is characterized.
  2. 　前記エッチング処理は、酸性溶液又はアルカリ性溶液による化学エッチングである、請求項１に記載の製造方法。 The manufacturing method according to claim 1, wherein the etching treatment is chemical etching using an acidic solution or an alkaline solution.
  3. 　前記エッチング処理は、酸性溶液による化学エッチングである、請求項１に記載の製造方法。 The manufacturing method according to claim 1, wherein the etching treatment is chemical etching using an acidic solution.
  4. 　前記粉末の平均粒径Ｄ５０が１～１５μｍである、請求項１～３のいずれかに記載の製造方法。 The production method according to claim 1, wherein the powder has an average particle diameter D 50 of 1 to 15 μm.
  5. 　前記焼結の温度は、５６０℃以上６６０℃以下である、請求項１～４のいずれかに記載の製造方法。 The manufacturing method according to any one of claims 1 to 4, wherein the sintering temperature is 560 ° C or higher and 660 ° C or lower.
  6. 　前記焼結後の前記皮膜の厚みが３０～２０００μｍである、請求項１～５のいずれかに記載の製造方法。 The manufacturing method according to any one of claims 1 to 5, wherein the thickness of the film after the sintering is 30 to 2000 µm.
  7. 　前記焼結後の前記皮膜の細孔径は、１．３μｍ以下である、請求項１～６のいずれかに記載の製造方法。 7. The manufacturing method according to claim 1, wherein the pore size of the film after the sintering is 1.3 μm or less.
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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04362102A (en) * 1991-06-06 1992-12-15 Showa Kiyabotsuto Suupaa Metal Kk Production of tantalum powder
JP2002060803A (en) * 2000-08-10 2002-02-28 Showa Kyabotto Super Metal Kk Method for producing tantalum sintered body for electrolytic capacitor
US6409796B1 (en) * 1999-10-08 2002-06-25 Advanced Alloy Technologies, Ltd. Method for production of tantalum and niobium powders with highly developed surface
WO2004045794A1 (en) * 2002-11-18 2004-06-03 Cbmm Asia Co.,Ltd. Nb-Al ALLOY POWDER AND METHOD FOR ELECTROLYTIC CAPACITOR AND METHOD FOR PREPARATION THEREOF, AND ELECTROLYTIC CAPACITOR
JP2009188417A (en) * 2003-11-10 2009-08-20 Showa Denko Kk Powder of niobium for capacitor, niobium sintered body, and capacitor
JP2010500771A (en) * 2006-08-16 2010-01-07 ハー．ツェー．スタルク ゲゼルシャフト ミット ベシュレンクテル ハフツング Semi-finished product having structured sintered active surface and method for producing the same
JP2012162770A (en) * 2011-02-07 2012-08-30 Kanagawa Acad Of Sci & Technol Porous microparticle and method for manufacturing the same
JP2014065940A (en) * 2012-09-25 2014-04-17 Nippon Light Metal Co Ltd Porous aluminum body, aluminum electrolytic capacitor, and method of manufacturing porous aluminum body
US20140259580A1 (en) * 2013-03-14 2014-09-18 Apaq Technology Co., Ltd. Method for fabricating solid electrolytic capacitors

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1711146A (en) * 2002-11-18 2005-12-21 Cbmm亚洲株式会社 Nb-Al alloy powder and method for electrolytic capacitor and method for preparation thereof, and electrolytic capacitor
JP4958510B2 (en) * 2006-10-10 2012-06-20 東洋アルミニウム株式会社 Electrode material for aluminum electrolytic capacitor and method for producing the same
JP6759067B2 (en) * 2016-11-18 2020-09-23 日本軽金属株式会社 Manufacturing method of electrodes for aluminum electrolytic capacitors

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04362102A (en) * 1991-06-06 1992-12-15 Showa Kiyabotsuto Suupaa Metal Kk Production of tantalum powder
US6409796B1 (en) * 1999-10-08 2002-06-25 Advanced Alloy Technologies, Ltd. Method for production of tantalum and niobium powders with highly developed surface
JP2002060803A (en) * 2000-08-10 2002-02-28 Showa Kyabotto Super Metal Kk Method for producing tantalum sintered body for electrolytic capacitor
WO2004045794A1 (en) * 2002-11-18 2004-06-03 Cbmm Asia Co.,Ltd. Nb-Al ALLOY POWDER AND METHOD FOR ELECTROLYTIC CAPACITOR AND METHOD FOR PREPARATION THEREOF, AND ELECTROLYTIC CAPACITOR
JP2009188417A (en) * 2003-11-10 2009-08-20 Showa Denko Kk Powder of niobium for capacitor, niobium sintered body, and capacitor
JP2010500771A (en) * 2006-08-16 2010-01-07 ハー．ツェー．スタルク ゲゼルシャフト ミット ベシュレンクテル ハフツング Semi-finished product having structured sintered active surface and method for producing the same
JP2012162770A (en) * 2011-02-07 2012-08-30 Kanagawa Acad Of Sci & Technol Porous microparticle and method for manufacturing the same
JP2014065940A (en) * 2012-09-25 2014-04-17 Nippon Light Metal Co Ltd Porous aluminum body, aluminum electrolytic capacitor, and method of manufacturing porous aluminum body
US20140259580A1 (en) * 2013-03-14 2014-09-18 Apaq Technology Co., Ltd. Method for fabricating solid electrolytic capacitors

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