JP3478039B2 - Method of forming electrode foil for aluminum electrolytic capacitor - Google Patents
Method of forming electrode foil for aluminum electrolytic capacitorInfo
- Publication number
- JP3478039B2 JP3478039B2 JP02353597A JP2353597A JP3478039B2 JP 3478039 B2 JP3478039 B2 JP 3478039B2 JP 02353597 A JP02353597 A JP 02353597A JP 2353597 A JP2353597 A JP 2353597A JP 3478039 B2 JP3478039 B2 JP 3478039B2
- Authority
- JP
- Japan
- Prior art keywords
- aluminum foil
- solution
- formation
- aqueous solution
- immersed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Chemical Treatment Of Metals (AREA)
- Fixed Capacitors And Capacitor Manufacturing Machines (AREA)
Description
【発明の詳細な説明】
【０００１】
【発明の属する技術分野】本発明はアルミ電解コンデン
サ用電極箔の化成方法に関するものである。
【０００２】
【従来の技術】一般にアルミ電解コンデンサは、高純度
のアルミ箔に電解エッチング処理を行ってその実効表面
積を拡大させたアルミ箔の表面に陽極化成処理によって
誘電体となる陽極酸化皮膜を形成して陽極箔を構成し、
そしてこの陽極箔と陰極箔をその間にセパレータを介在
させて巻回することによりコンデンサ素子を構成し、さ
らにこのコンデンサ素子に駆動用電解液を含浸させた
後、コンデンサ素子を有底筒状の金属ケース内に収納
し、かつ金属ケースの開口部を封口部材で封止すること
により構成している。
【０００３】近年、アルミ電解コンデンサはより一層の
小形化、高容量化、高信頼性化が要求されており、それ
に伴いアルミ電解コンデンサ用電極箔においてもさらな
る漏れ電流の低減と静電容量の増大が要求されている。
【０００４】従来のアルミ電解コンデンサ用電極箔の化
成方法は、電解エッチング処理を行ったアルミ箔を純水
中で水和処理し、その後、燐酸、硼酸、有機酸あるいは
その塩のいずれか１種以上を含む水溶液（本化成液）に
アルミ箔を浸漬すると同時に所定電圧を印加することに
より本化成を行ってアルミ箔の表面に陽極酸化皮膜を形
成し、その後、欠陥部を修復させるための熱処理等によ
る減極処理を行い、さらにその後、燐酸、硼酸、有機酸
あるいはその塩のいずれか１種以上を含む水溶液（再化
成液）にアルミ箔を再び浸漬すると同時に所定電圧を印
加することにより再化成を行ってアルミ箔の表面に所望
耐電圧厚さの陽極酸化皮膜を形成するようにしていた。
【０００５】
【発明が解決しようとする課題】しかしながら、上記し
た従来のアルミ電解コンデンサ用電極箔の化成方法にお
いては、減極処理後、再化成を行う場合、燐酸、硼酸、
有機酸あるいはその塩のいずれか１種以上を含む水溶液
（再化成液）にアルミ箔を再び浸漬すると同時に所定電
圧を印加することにより再化成を行うようにしているた
め、減極処理によって暴露された陽極酸化皮膜内部の欠
陥中に前記水溶液（再化成液）が浸透する以前に所定電
圧が印加されることになり、これにより、従来の再化成
においては、陽極酸化皮膜の内部に欠陥を多く残した陽
極酸化皮膜が形成されて、漏れ電流が増大するという問
題点を有していた。
【０００６】本発明は上記従来の問題点を解決するもの
で、漏れ電流の低減が図れるアルミ電解コンデンサ用電
極箔の化成方法を提供することを目的とするものであ
る。
【０００７】
【課題を解決するための手段】上記目的を達成するため
に本発明のアルミ電解コンデンサ用電極箔の化成方法
は、電解エッチング処理を行ったアルミ箔を水溶液（本
化成液）に浸漬すると同時に所定電圧を印加することに
より本化成を行い、その後、欠陥部修復のための減極処
理を行い、さらにその後、燐酸、硼酸、有機酸あるいは
その塩のいずれか１種以上を含む水溶液（再化成液）に
所定時間浸漬するとともに、この所定時間経過後にアル
ミ箔に所定電圧を印加することにより再化成を行うよう
にしたもので、この化成方法によれば、漏れ電流の低減
が図れるものである。
【０００８】
【発明の実施の形態】本発明の請求項１に記載の発明
は、電解エッチング処理を行ったアルミ箔を水溶液（本
化成液）に浸漬すると同時に所定電圧を印加することに
より本化成を行い、その後、欠陥部修復のための減極処
理を行い、さらにその後、燐酸、硼酸、有機酸あるいは
その塩のいずれか１種以上を含む水溶液（再化成液）に
所定時間浸漬するとともに、その所定時間経過後にアル
ミ箔に所定電圧を印加することにより再化成を行うよう
にしたもので、この化成方法によれば、燐酸、硼酸、有
機酸あるいはその塩のいずれか１種以上を含む水溶液
（再化成液）にアルミ箔を所定時間浸漬するとともに、
この所定時間経過後にアルミ箔に所定電圧を印加するこ
とにより再化成を行うようにしているため、減極処理に
よって暴露された陽極酸化皮膜内部の欠陥中に前記水溶
液（再化成液）が所定時間の浸漬により浸透することに
なり、そしてこの浸透した状態で再化成が始まるため、
陽極酸化皮膜内部の欠陥は大部分が修復されることにな
り、これにより、漏れ電流の低減を図ることができるも
のである。
【０００９】以下、本発明の実施の形態と比較例につい
て説明する。
（実施の形態１）純度９９．９９％、厚み１００μｍの
アルミ箔に電解エッチング処理を行ってその実効表面積
を拡大させ、そしてこのアルミ箔を９８℃以上の純水中
に１０分間浸漬して水和処理を行い、その後、このアル
ミ箔を液温が９０℃で、かつ濃度が１００ｇ／ｌの硼酸
と０．５ｇ／ｌの硼酸ナトリウムの混合水溶液（本化成
液）に浸漬すると同時に１００ｍＡ／ｃｍ2の電流密度
で５００Ｖの電圧を印加することにより本化成を行って
アルミ箔の表面に陽極酸化皮膜を形成し、そして化成開
始１２０分後に電圧印加を終了し、その後、陽極酸化皮
膜の欠陥部修復のために５００℃で３分の熱処理を施す
ことにより減極処理を行い、さらにその後、減極処理が
なされたアルミ箔を液温が９０℃で、かつ濃度が１００
ｇ／ｌの硼酸と０．５ｇ／ｌの硼酸ナトリウムの混合水
溶液（再化成液）に１２０秒間浸漬するとともに、１２
０秒経過後に１００ｍＡ／ｃｍ2の電流密度で５００Ｖ
の電圧を印加することにより再化成を行ってアルミ箔の
表面に所望耐電圧厚さの陽極酸化皮膜を形成した。
【００１０】（実施の形態２）純度９９．９９％、厚み
１００μｍのアルミ箔に電解エッチング処理を行ってそ
の実効表面積を拡大させ、そしてこのアルミ箔を９８℃
以上の純水中に１０分間浸漬して水和処理を行い、その
後、このアルミ箔を液温が９０℃で、かつ濃度が１００
ｇ／ｌの硼酸と０．５ｇ／ｌの硼酸ナトリウムの混合水
溶液（本化成液）に浸漬すると同時に１００ｍＡ／ｃｍ
2の電流密度で５００Ｖの電圧を印加することにより本
化成を行ってアルミ箔の表面に陽極酸化皮膜を形成し、
そして化成開始３０分後に電圧印加を終了し、その後、
陽極酸化皮膜の欠陥部修復のために５００℃で３分の熱
処理を施すことにより減極処理を行い、さらにその後、
減極処理がなされたアルミ箔を液温が９０℃で、かつ濃
度が１００ｇ／ｌの硼酸と０．５ｇ／ｌの硼酸ナトリウ
ムの混合水溶液（再化成液）に６０秒間浸漬するととも
に、６０秒経過後に１００ｍＡ／ｃｍ2の電流密度で５
００Ｖの電圧を印加することにより再化成を行ってアル
ミ箔の表面に所望耐電圧厚さの陽極酸化皮膜を形成し
た。
【００１１】（実施の形態３）純度９９．９９％、厚み
１００μｍのアルミ箔に電解エッチング処理を行ってそ
の実効表面積を拡大させ、そしてこのアルミ箔を９８℃
以上の純水中に１０分間浸漬して水和処理を行い、その
後、このアルミ箔を液温が９０℃で、かつ濃度が１００
ｇ／ｌの硼酸と０．５ｇ／ｌの硼酸ナトリウムの混合水
溶液（本化成液）に浸漬すると同時に１００ｍＡ／ｃｍ
2の電流密度で５００Ｖの電圧を印加することにより本
化成を行ってアルミ箔の表面に陽極酸化皮膜を形成し、
そして化成開始３０分後に電圧印加を終了し、その後、
陽極酸化皮膜の欠陥部修復のために５００℃で３分の熱
処理を施すことにより減極処理を行い、さらにその後、
減極処理がなされたアルミ箔を液温が９０℃で、かつ濃
度が１００ｇ／ｌの硼酸と０．５ｇ／ｌの硼酸ナトリウ
ムの混合水溶液（再化成液）に１５秒間浸漬するととも
に、１５秒経過後に１００ｍＡ／ｃｍ2の電流密度で５
００Ｖの電圧を印加することにより再化成を行ってアル
ミ箔の表面に所望耐電圧厚さの陽極酸化皮膜を形成し
た。
【００１２】（比較例）純度９９．９９％、厚み１００
μｍのアルミ箔に電解エッチング処理を行ってその実効
表面積を拡大させ、そしてこのアルミ箔を９８℃以上の
純水中に１０分間浸漬して水和処理を行い、その後、こ
のアルミ箔を液温が９０℃で、かつ濃度が１００ｇ／ｌ
の硼酸と０．５ｇ／ｌの硼酸ナトリウムの混合水溶液
（本化成液）に浸漬すると同時に１００ｍＡ／ｃｍ2の
電流密度で５００Ｖの電圧を印加することにより本化成
を行ってアルミ箔の表面に陽極酸化皮膜を形成し、そし
て化成開始３０分後に電圧印加を終了し、その後、陽極
酸化皮膜の欠陥部修復のために５００℃で３分の熱処理
を施すことにより減極処理を行い、さらにその後、減極
処理がなされたアルミ箔を液温が９０℃で、かつ濃度が
１００ｇ／ｌの硼酸と０．５ｇ／ｌの硼酸ナトリウムの
混合水溶液（再化成液）に浸漬すると同時に１００ｍＡ
／ｃｍ2の電流密度で５００Ｖの電圧を印加することに
より再化成を行ってアルミ箔の表面に所望耐電圧厚さの
陽極酸化皮膜を形成した。
【００１３】（表１）は本発明の実施の形態１，２，３
により得られた電極箔と、比較例により得られた電極箔
における漏れ電流を示したものである。
【００１４】
【表１】
【００１５】（表１）から明らかなように、比較例は本
化成後の減極処理がなされたアルミ箔の再化成を行う場
合、前記アルミ箔を再化成液に浸漬すると同時に所定電
圧を印加するようにしているため、アルミ箔には再化成
液への浸漬と同時に電流が流れることになり、これによ
り、減極処理によって暴露された陽極酸化皮膜内部の欠
陥中に前記再化成液が浸透する以前に所定電圧の印加に
よる再化成が始まるため、欠陥の十分な修復を行うこと
ができず、陽極酸化皮膜の内部に欠陥を多く残す形とな
り、その結果、漏れ電流は（表１）に示すような特性を
示した。
【００１６】これに対し、本発明の実施の形態１は本化
成後の減極処理がなされたアルミ箔の再化成を行う場
合、前記アルミ箔を再化成液に１２０秒間浸漬した後、
５００Ｖの電圧を印加することにより再化成を行うよう
にしているため、減極処理によって暴露された陽極酸化
皮膜内部の欠陥中にあらかじめ再化成液が浸透すること
になり、そしてこの浸透した状態で再化成が始まるた
め、陽極酸化皮膜内部の欠陥は大部分が修復されること
になり、これにより、漏れ電流は（表１）に示すような
特性を示した。
【００１７】また本発明の実施の形態２は本化成後の減
極処理がなされたアルミ箔の再化成を行う場合、前記ア
ルミ箔を再化成液に６０秒間浸漬した後、５００Ｖの電
圧を印加することにより再化成を行うようにしているた
め、減極処理によって暴露された陽極酸化皮膜内部の欠
陥中にあらかじめ再化成液が浸透することになり、そし
てこの浸透した状態で再化成が始まるため、陽極酸化皮
膜内部の欠陥は大部分が修復されることになり、これに
より、漏れ電流は（表１）に示すような特性を示した。
【００１８】そしてまた本発明の実施の形態３は本化成
後の減極処理がなされたアルミ箔の再化成を行う場合、
前記アルミ箔を再化成液に１５秒間浸漬した後、５００
Ｖの電圧を印加することにより再化成を行うようにして
いるため、減極処理によって暴露された陽極酸化皮膜内
部の欠陥中にあらかじめ再化成液が浸透するが、この場
合、浸漬時間が短いため、減極処理によって暴露された
陽極酸化皮膜内部の欠陥の一部には再化成液が浸漬しな
い部分が残り、その結果、漏れ電流は（表１）に示すよ
うな特性を示した。
【００１９】このように本発明の実施の形態１，２，３
においては比較例に比べて漏れ電流を５〜２５％低減す
ることができるものである。
【００２０】なお、上記本発明の実施の形態１，２，３
においては、再化成液として硼酸と硼酸ナトリウムの混
合水溶液を用いているが、これに限定されるものではな
く、例えばこれ以外の燐酸、硼酸、有機酸あるいはその
塩のいずれか１種以上を含む水溶液を用いても、本発明
の実施の形態１，２，３と同様の作用効果を奏するもの
である。
【００２１】
【発明の効果】以上のように本発明のアルミ電解コンデ
ンサ用電極箔の化成方法は、電解エッチング処理を行っ
たアルミ箔を水溶液に浸漬すると同時に所定電圧を印加
することにより本化成を行い、その後、欠陥部修復のた
めの減極処理を行い、さらにその後、燐酸、硼酸、有機
酸あるいはその塩のいずれか１種以上を含む水溶液に所
定時間浸漬するとともに、この所定時間経過後にアルミ
箔に所定電圧を印加することにより再化成を行うように
したもので、この化成方法によれば、燐酸、硼酸、有機
酸あるいはその塩のいずれか１種以上を含む水溶液にア
ルミ箔を所定時間浸漬するとともに、この所定時間経過
後にアルミ箔に所定電圧を印加することにより再化成を
行うようにしているため、減極処理によって暴露された
陽極酸化皮膜内部の欠陥中に前記水溶液（再化成液）が
所定時間の浸漬により浸透することになり、そしてこの
浸透した状態で再化成が始まるため、陽極酸化皮膜内部
の欠陥は大部分が修復されることになり、これにより、
漏れ電流の低減を図ることができるものである。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming an electrode foil for an aluminum electrolytic capacitor. 2. Description of the Related Art In general, an aluminum electrolytic capacitor is formed by subjecting a high-purity aluminum foil to electrolytic etching to increase the effective surface area of the aluminum foil. To form the anode foil,
Then, a capacitor element is formed by winding the anode foil and the cathode foil with a separator interposed therebetween, and further impregnating the capacitor element with a driving electrolyte. It is configured by being housed in a case and sealing the opening of the metal case with a sealing member. In recent years, aluminum electrolytic capacitors have been required to be further reduced in size, increased in capacity, and increased in reliability. Accordingly, in electrode foils for aluminum electrolytic capacitors, further reduction in leakage current and increase in capacitance have been required. Is required. A conventional method for forming an electrode foil for an aluminum electrolytic capacitor is to hydrate an electrolytically etched aluminum foil in pure water, and then add one of phosphoric acid, boric acid, an organic acid or a salt thereof. The aluminum foil is immersed in an aqueous solution containing the above (the chemical conversion solution), and at the same time, a predetermined voltage is applied to perform the chemical conversion to form an anodic oxide film on the surface of the aluminum foil, followed by a heat treatment for repairing the defective portion. After that, the aluminum foil is immersed again in an aqueous solution (reformation solution) containing at least one of phosphoric acid, boric acid, an organic acid or a salt thereof, and at the same time, a predetermined voltage is applied to the aluminum foil. The anodized film having a desired withstand voltage thickness is formed on the surface of the aluminum foil by chemical conversion. [0005] However, in the above-mentioned conventional method for forming an electrode foil for an aluminum electrolytic capacitor, in the case of performing re-formation after depolarization treatment, phosphoric acid, boric acid,
The aluminum foil is immersed again in an aqueous solution (reformation solution) containing at least one of an organic acid or a salt thereof and, at the same time, re-formation is performed by applying a predetermined voltage. A predetermined voltage is applied before the aqueous solution (reformation solution) penetrates into the defects inside the anodized film, thereby increasing the number of defects inside the anodized film in the conventional re-formation. There is a problem that the remaining anodic oxide film is formed and the leakage current increases. An object of the present invention is to provide a method for forming an electrode foil for an aluminum electrolytic capacitor which can reduce the leakage current by solving the above-mentioned conventional problems. In order to achieve the above object, a method of forming an electrode foil for an aluminum electrolytic capacitor according to the present invention comprises immersing an electrolytically etched aluminum foil in an aqueous solution (a chemical conversion solution). At the same time, this chemical conversion is performed by applying a predetermined voltage, followed by depolarization treatment for repairing a defective portion, and thereafter, an aqueous solution containing at least one of phosphoric acid, boric acid, an organic acid or a salt thereof ( Re-formation liquid) for a predetermined time, and after the predetermined time has passed, a predetermined voltage is applied to the aluminum foil to perform the re-formation. According to this formation method, the leakage current can be reduced. It is. DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is characterized in that an aluminum foil subjected to electrolytic etching is immersed in an aqueous solution (chemical conversion solution) and a predetermined voltage is applied at the same time. After that, a depolarization treatment for repairing a defective portion is performed, and thereafter, the substrate is immersed in an aqueous solution (re-chemical solution) containing at least one of phosphoric acid, boric acid, an organic acid or a salt thereof for a predetermined time, After the predetermined time, a predetermined voltage is applied to the aluminum foil to perform re-chemical formation. According to this chemical formation method, an aqueous solution containing at least one of phosphoric acid, boric acid, an organic acid and a salt thereof is used. (Reformation solution) while immersing the aluminum foil for a predetermined time,
After the lapse of the predetermined time, the re-chemical conversion is performed by applying a predetermined voltage to the aluminum foil. Therefore, the aqueous solution (re-chemical conversion liquid) is supplied for a predetermined time in the defect inside the anodized film exposed by the depolarization treatment. Will be permeated by immersion, and re-formation starts in this permeated state,
Most of the defects inside the anodic oxide film will be repaired, whereby the leakage current can be reduced. Hereinafter, embodiments of the present invention and comparative examples will be described. (Embodiment 1) An aluminum foil having a purity of 99.99% and a thickness of 100 μm is subjected to electrolytic etching to increase its effective surface area, and this aluminum foil is immersed in pure water of 98 ° C. or more for 10 minutes to obtain water. Then, the aluminum foil is immersed in a mixed aqueous solution of boric acid having a liquid temperature of 90 ° C. and sodium borate having a concentration of 100 g / l (0.5 g / l) (this chemical conversion solution) at the same time as 100 mA / cm. This chemical conversion was performed by applying a voltage of 500 V at a current density of 2 to form an anodic oxide film on the surface of the aluminum foil, and the voltage application was terminated 120 minutes after the start of the chemical formation. A depolarization treatment is performed by performing a heat treatment at 500 ° C. for 3 minutes for restoration, and then the depolarized aluminum foil is treated at a liquid temperature of 90 ° C. and a concentration of 100 ° C.
g / l boric acid and 0.5 g / l sodium borate in a mixed aqueous solution (reformation solution) for 120 seconds,
After 0 seconds, 500 V at a current density of 100 mA / cm 2
To form an anodic oxide film having a desired withstand voltage thickness on the surface of the aluminum foil. (Embodiment 2) An aluminum foil having a purity of 99.99% and a thickness of 100 μm is subjected to electrolytic etching to increase its effective surface area.
The aluminum foil was immersed in the above pure water for 10 minutes to perform a hydration treatment.
g / l boric acid and 0.5 g / l sodium borate mixed solution (this chemical solution) and at the same time 100 mA / cm
This chemical conversion is performed by applying a voltage of 500 V at a current density of 2 to form an anodic oxide film on the surface of the aluminum foil,
Then, after 30 minutes from the start of chemical formation, the voltage application is terminated.
A depolarization treatment is performed by performing a heat treatment at 500 ° C. for 3 minutes for repairing a defective portion of the anodic oxide film, and thereafter,
The aluminum foil subjected to the depolarization treatment is immersed for 60 seconds in a mixed aqueous solution (reformation solution) of boric acid having a liquid temperature of 90 ° C. and a concentration of 100 g / l and sodium borate having a concentration of 0.5 g / l for 60 seconds. After a lapse of 5 minutes at a current density of 100 mA / cm 2
Re-chemical formation was performed by applying a voltage of 00 V to form an anodic oxide film having a desired withstand voltage thickness on the surface of the aluminum foil. (Embodiment 3) An aluminum foil having a purity of 99.99% and a thickness of 100 μm is subjected to electrolytic etching to increase its effective surface area.
The aluminum foil was immersed in the above pure water for 10 minutes to perform a hydration treatment.
g / l boric acid and 0.5 g / l sodium borate mixed solution (this chemical solution) and at the same time 100 mA / cm
This chemical conversion is performed by applying a voltage of 500 V at a current density of 2 to form an anodic oxide film on the surface of the aluminum foil,
Then, after 30 minutes from the start of chemical formation, the voltage application is terminated.
A depolarization treatment is performed by performing a heat treatment at 500 ° C. for 3 minutes for repairing a defective portion of the anodic oxide film, and thereafter,
The depolarized aluminum foil is immersed for 15 seconds in a mixed aqueous solution (reformation solution) of boric acid of 100 g / l and 0.5 g / l of sodium borate at a solution temperature of 90 ° C. and a concentration of 0.5 g / l for 15 seconds. After a lapse of 5 minutes at a current density of 100 mA / cm 2
Re-chemical formation was performed by applying a voltage of 00 V to form an anodic oxide film having a desired withstand voltage thickness on the surface of the aluminum foil. (Comparative Example) Purity 99.99%, thickness 100
The effective surface area of the aluminum foil is increased by performing an electrolytic etching process on the aluminum foil, and the aluminum foil is immersed in pure water of 98 ° C. or higher for 10 minutes to perform a hydration process. Is 90 ° C and the concentration is 100 g / l
Immersion in a mixed aqueous solution of boric acid and 0.5 g / l of sodium borate (former chemical solution), and simultaneously applying a voltage of 500 V at a current density of 100 mA / cm 2 to form an anode on the surface of the aluminum foil An oxide film is formed, and the voltage application is terminated 30 minutes after the start of chemical formation. Thereafter, a heat treatment is performed at 500 ° C. for 3 minutes to repair a defective portion of the anodic oxide film, thereby performing depolarization treatment. The depolarized aluminum foil is immersed in a mixed aqueous solution of boric acid (concentration: 100 g / l) and sodium borate (0.5 g / l) (reformation solution) at a liquid temperature of 90 ° C. and at a concentration of 100 mA.
Reforming was performed by applying a voltage of 500 V at a current density of / cm 2 to form an anodic oxide film having a desired withstand voltage thickness on the surface of the aluminum foil. Table 1 shows Embodiments 1, 2, and 3 of the present invention.
3 shows leakage currents in the electrode foil obtained in Example 1 and the electrode foil obtained in Comparative Example. [Table 1] As is clear from Table 1, in the comparative example, when the aluminum foil subjected to the depolarization treatment after the chemical conversion is re-formed, the aluminum foil is immersed in the re-forming solution and a predetermined voltage is applied at the same time. As a result, current flows in the aluminum foil at the same time as immersion in the re-formation solution, whereby the re-formation solution penetrates into defects inside the anodized film exposed by the depolarization treatment. Before the formation, re-chemical formation by application of a predetermined voltage starts, so that the defect cannot be repaired sufficiently and many defects are left inside the anodic oxide film. As a result, the leakage current is reduced to (Table 1). The characteristics shown are shown. On the other hand, according to the first embodiment of the present invention, when the aluminum foil subjected to the depolarization treatment after the chemical conversion is to be re-formed, the aluminum foil is immersed in a re-forming solution for 120 seconds.
Since the re-formation is performed by applying a voltage of 500 V, the re-formation solution permeates in advance into the defects inside the anodic oxide film exposed by the depolarization treatment, and in this permeated state Since the re-formation starts, most of the defects inside the anodic oxide film are repaired, whereby the leakage current has the characteristics shown in (Table 1). In the second embodiment of the present invention, when performing re-formation of the depolarized aluminum foil after the chemical conversion, the aluminum foil is immersed in a re-formation solution for 60 seconds, and then a voltage of 500 V is applied. As a result, the re-chemical conversion liquid permeates into the defects inside the anodized film exposed by the depolarization treatment in advance, and the re-chemical conversion starts in this permeated state. Most of the defects inside the anodic oxide film were repaired, and as a result, the leakage current exhibited characteristics as shown in (Table 1). In the third embodiment of the present invention, when the aluminum foil subjected to the depolarization treatment after the chemical conversion is re-formed,
After immersing the aluminum foil in the re-formulation solution for 15 seconds, 500
Since the re-chemical conversion is performed by applying a voltage of V, the re-chemical conversion liquid penetrates in advance into the defects inside the anodized film exposed by the depolarization treatment, but in this case, the immersion time is short. A part of the defect inside the anodic oxide film exposed by the depolarization treatment had a part where the re-chemical conversion liquid was not immersed, and as a result, the leakage current exhibited characteristics as shown in (Table 1). As described above, Embodiments 1, 2, and 3 of the present invention
In the example, the leakage current can be reduced by 5 to 25% as compared with the comparative example. The first, second, and third embodiments of the present invention are described.
In the above, a mixed aqueous solution of boric acid and sodium borate is used as a rechemical solution, but the present invention is not limited to this, and may include, for example, any one or more of phosphoric acid, boric acid, organic acids, and salts thereof. Even when an aqueous solution is used, the same functions and effects as those of the first, second, and third embodiments of the present invention can be obtained. As described above, the method for forming an electrode foil for an aluminum electrolytic capacitor according to the present invention comprises immersing the aluminum foil subjected to electrolytic etching in an aqueous solution and simultaneously applying a predetermined voltage to the electrode foil. After that, a depolarizing process for repairing the defective portion is performed, and thereafter, the substrate is immersed in an aqueous solution containing at least one of phosphoric acid, boric acid, an organic acid or a salt thereof for a predetermined time, and after the lapse of the predetermined time, the aluminum According to this chemical conversion method, the aluminum foil is placed in an aqueous solution containing at least one of phosphoric acid, boric acid, an organic acid or a salt thereof for a predetermined time by applying a predetermined voltage to the foil. The anode exposed by the depolarization treatment is immersed, and after this predetermined time has passed, the aluminum foil is subjected to re-formation by applying a predetermined voltage to the aluminum foil. The aqueous solution (reformation solution) permeates into the defects inside the oxide film by immersion for a predetermined time, and re-formation starts in this permeated state, so that most of the defects inside the anodic oxide film are repaired. Which means that
The leakage current can be reduced.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 小島 浩一 大阪府門真市大字門真1006番地 松下電 器産業株式会社内 (56)参考文献 特開 平８−64480（ＪＰ，Ａ) 特開 平８−316111（ＪＰ，Ａ) 特開 平４−74406（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H01G 9/04 301 H01G 9/04 307 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Kojima 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-8-64480 (JP, A) JP-A 8- 316111 (JP, A) JP-A-4-74406 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) H01G 9/04 301 H01G 9/04 307
Claims (1)
水溶液（本化成液）に浸漬すると同時に所定電圧を印加
することにより本化成を行い、その後、欠陥部修復のた
めの減極処理を行い、さらにその後、燐酸、硼酸、有機
酸あるいはその塩のいずれか１種以上を含む水溶液（再
化成液）に所定時間浸漬するとともに、この所定時間経
過後にアルミ箔に所定電圧を印加することにより再化成
を行うようにしたアルミ電解コンデンサ用電極箔の化成
方法。(57) [Claims] [Claim 1] The aluminum foil which has been subjected to the electrolytic etching treatment is immersed in an aqueous solution (a chemical conversion solution), and at the same time, a predetermined voltage is applied to perform the chemical conversion, and thereafter, the defective portion is repaired. And then immersed in an aqueous solution (reformation solution) containing at least one of phosphoric acid, boric acid, an organic acid or a salt thereof for a predetermined time and, after the lapse of the predetermined time, applied to an aluminum foil. A method of forming an electrode foil for an aluminum electrolytic capacitor in which re-formation is performed by applying a predetermined voltage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02353597A JP3478039B2 (en) | 1997-02-06 | 1997-02-06 | Method of forming electrode foil for aluminum electrolytic capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02353597A JP3478039B2 (en) | 1997-02-06 | 1997-02-06 | Method of forming electrode foil for aluminum electrolytic capacitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10223483A JPH10223483A (en) | 1998-08-21 |
| JP3478039B2 true JP3478039B2 (en) | 2003-12-10 |
Family
ID=12113164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP02353597A Expired - Fee Related JP3478039B2 (en) | 1997-02-06 | 1997-02-06 | Method of forming electrode foil for aluminum electrolytic capacitor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3478039B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006210837A (en) * | 2005-01-31 | 2006-08-10 | Nichicon Corp | Solid electrolytic capacitor and method for manufacturing the same |
| JP4662268B2 (en) * | 2005-12-27 | 2011-03-30 | ニチコン株式会社 | Method for producing electrode foil for electrolytic capacitor |
| EP2312597A4 (en) | 2008-07-29 | 2018-04-04 | Showa Denko K.K. | Method for manufacturing niobium solid electrolytic capacitor |
| JP5490446B2 (en) | 2009-06-18 | 2014-05-14 | パナソニック株式会社 | Method for producing anode foil for aluminum electrolytic capacitor |
| CN111968859B (en) * | 2020-07-22 | 2022-03-18 | 博罗冠业电子有限公司 | Method for manufacturing formed foil and aluminum electrolytic capacitor negative electrode foil |
-
1997
- 1997-02-06 JP JP02353597A patent/JP3478039B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10223483A (en) | 1998-08-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2663544B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JPH0235443B2 (en) | ||
| JP3478039B2 (en) | Method of forming electrode foil for aluminum electrolytic capacitor | |
| JPH06275473A (en) | Production of anode foil for aluminum electrolytic capacitor | |
| JP2727823B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JP2663541B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JP3853432B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JPH09246111A (en) | Formation of electrode foil for aluminum electrolytic capacitor | |
| JPH10112423A (en) | Formation method for anodic foil for aluminum electrolytic capacitor | |
| JP3582451B2 (en) | Manufacturing method of anode foil for aluminum electrolytic capacitor | |
| JP3480311B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JP3467827B2 (en) | Manufacturing method of anode foil for aluminum electrolytic capacitor | |
| JP3453984B2 (en) | Manufacturing method of etching foil for aluminum electrolytic capacitor | |
| JPH04279017A (en) | Manufacture of electrode foil for aluminum electrolytic capacitor | |
| JP3309177B2 (en) | Surface enlargement treatment method for electrode foil for aluminum electrolytic capacitor | |
| JPH09246110A (en) | Method transforming aluminum electrolytic capacitor anode foil | |
| JP3483681B2 (en) | Method of manufacturing tab terminal for electrolytic capacitor | |
| JPH04196305A (en) | Manufacture of electrode foil for aluminum electrolytic capacitor | |
| JPH0774055A (en) | Electrolytic capacitor and its tab terminal | |
| JP2738160B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JP3544768B2 (en) | Method of forming electrode foil for electrolytic capacitor | |
| JPH06132172A (en) | Manufacture of tab terminal for electrolytic capacitor | |
| JP2743600B2 (en) | Method for producing electrode foil for aluminum electrolytic capacitor | |
| JP2003115420A (en) | Anode foil for aluminum electrolytic capacitor and its chemically forming method | |
| JPH02114506A (en) | Manufacture of aluminum electrolytic capacitor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20071003 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081003 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091003 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091003 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101003 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111003 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121003 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20131003 Year of fee payment: 10 |
|
| LAPS | Cancellation because of no payment of annual fees |