JPS59124119A - Method of producing solid electrolytic condenser - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 本発明は固体電解コンデンサの製造方法に８Ｑづるもの
である。DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a method for manufacturing a solid electrolytic capacitor.

従来、タンタル等の弁作用金属を陽極体とする固体電解
コンデンサは、二酸化マンガン等の半導体層を形成する
のに、硝酸マンガン等の溶液又は融液中に陽極体を浸漬
し次に適当な湿度で加熱分解する方法が用いられている
。しかし、この方法では、加熱分解のときに発生するＮ
ＯｘガスのＩＣめに、半導体層が均質で一様な薄い層に
ならず多孔質で粘着性の乏しいものとなる。そのため、
半導体層自体の抵抗及び半導体層上に設けられるカーボ
ン層との接触抵抗が大ぎくなり、コンデンサの損失が大
きくなる欠点があった。Conventionally, solid electrolytic capacitors using a valve metal such as tantalum as an anode body have been manufactured by immersing the anode body in a solution or melt of manganese nitrate or the like to form a semiconductor layer of manganese dioxide or the like, and then immersing the anode body in a solution or melt of manganese nitrate, etc. A method of thermal decomposition is used. However, with this method, N generated during thermal decomposition
For Ox gas ICs, the semiconductor layer is not a homogeneous, uniformly thin layer, but is porous and has poor adhesiveness. Therefore,
This has the disadvantage that the resistance of the semiconductor layer itself and the contact resistance with the carbon layer provided on the semiconductor layer become large, resulting in large losses in the capacitor.

また、熱分解を蒸気雰囲気中で行うと均質で一様な薄い
層が形成されることが公知であるが、熱分解温度が２３
０℃を越え、そのために、二酸化マンガン等がとびちり
、陽極体から引き出されているタンタル等のリード線に
付着し、このリード線と端子とを溶接する際に火花が飛
び危険であり、作業が困離になる欠点があり、また、一
般に漏れ電流が増大する欠点もあった。It is also known that a homogeneous and uniform thin layer is formed when pyrolysis is carried out in a steam atmosphere;
If the temperature exceeds 0℃, manganese dioxide etc. will fly out and adhere to the tantalum etc. lead wire drawn out from the anode body, and when welding this lead wire and the terminal, sparks will fly off and the work will be dangerous. This has the disadvantage of being difficult to use, and also has the disadvantage of generally increasing leakage current.

本発明は、以上の欠点を改良し、作業が容易で損失や漏
れ電流等の各特性を改良しうる固体電解コンデンサの製
造方法の提供を目的とするものである。SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a solid electrolytic capacitor which can improve the above-mentioned drawbacks, is easy to work with, and can improve various characteristics such as loss and leakage current.

本発明は上記の目的を達成するために、陽極酸化皮膜形
成後の焼結体を半導体母液に浸漬した後、温度２００℃
〜３５０℃の蒸気雰囲気中で熱分解し、次に、温度２０
０℃以下の蒸気雰囲気中で熱分解して半導体層を設ける
ことを特徴とする固体電解コンデンサの製造方法を提供
するものである。In order to achieve the above object, the present invention immerses a sintered body after forming an anodized film in a semiconductor mother liquor, and then heats the body at a temperature of 200°C.
Pyrolysis in a steam atmosphere at ~350°C, then at a temperature of 20°C.
The present invention provides a method for manufacturing a solid electrolytic capacitor, characterized in that a semiconductor layer is provided by thermal decomposition in a steam atmosphere at 0° C. or lower.

また、本発明は、上記の目的を達成づ−るために、陽極
酸化皮膜形成後の焼結体を半導体母液中に浸漬して温度
２００℃〜３５０℃の蒸気雰囲気中において熱分解した
後、硝酸アンモン、尿素、ギ酸及びアルコール類等の還
元剤が少なくとも一種類添加された半導体母液中に浸漬
し温度２００℃以下の蒸気雰囲気中において熱分解して
半導体層を設けることを特徴とする固体電解コンデンサ
の製造方法を提供するものである。In addition, in order to achieve the above object, the present invention provides that after immersing a sintered body with an anodized film formed thereon in a semiconductor mother liquor and thermally decomposing it in a steam atmosphere at a temperature of 200°C to 350°C, Solid electrolysis characterized by forming a semiconductor layer by immersing it in a semiconductor mother liquor to which at least one type of reducing agent such as ammonium nitrate, urea, formic acid, and alcohols has been added and thermally decomposing it in a steam atmosphere at a temperature of 200°C or less. A method for manufacturing a capacitor is provided.

さらに、本発明は、上記の目的を達成するために、陽極
酸化皮膜形成後の焼結体を半導体母液中に浸漬し渇麿２
００℃〜３５０℃の蒸気雰囲気中において熱分解し、次
に、硝酸アンモン、尿素、ギ酸及びアルコール類等の還
元剤を少な（とも一種類含むｉｌｌ　２００℃以下の蒸
気雰囲気中において熱分解し半導体層を設けることを特
徴とする固体電解コンデン°リ−のＩＩＩ造方法を提供
するものである。Furthermore, in order to achieve the above-mentioned object, the present invention involves immersing the sintered body after forming the anodic oxide film in a semiconductor mother liquor.
It is thermally decomposed in a steam atmosphere of 00℃ to 350℃, and then thermally decomposed in a steam atmosphere of 200℃ or less with a small amount of reducing agents such as ammonium nitrate, urea, formic acid, and alcohols. The present invention provides a third method for manufacturing solid electrolytic capacitors characterized by providing a layer.

すなわち、本発明は、半導体層を形成するのに、陽極酸
化皮膜形成後の焼結体を硝酸マンガン等の半導体母液中
に浸漬し２００℃〜３５０℃程度の温度範囲中で熱分解
することにより、焼結体の内部に微細な粒子からなる二
酸化マンガン等の半導体層を形成１′る。この段階では
半導体層が焼結体の内部に形成されるので、含浸した半
導体液は飛び散ることはない。そして次に、焼結体を、
通常のあるいは硝酸アンモンや尿素、ギ酸及びアルコー
ル類等の還元剤が少なくとも一種類添加された半導体母
液中に浸漬して温度２００℃以下の通常のあるいは硝酸
アンモン等の還元剤を少なくとも一種類含む蒸気雰囲気
中において熱分解し焼結体の外部にまで半導体層を形成
する。この際、熱分解温度が低いので半導体液の飛び散
りを防止でき、その後の端子の溶接作業が容易になり、
まＩこ、均質で一様な半導体層が外側に形成されるので
、全体として損失が改善され、漏れ電流特性が向上する
。That is, in the present invention, the semiconductor layer is formed by immersing the sintered body after forming the anodic oxide film in a semiconductor mother liquor such as manganese nitrate and thermally decomposing it in a temperature range of about 200°C to 350°C. A semiconductor layer made of fine particles such as manganese dioxide is formed inside the sintered body. At this stage, the semiconductor layer is formed inside the sintered body, so the impregnated semiconductor liquid does not scatter. Then, the sintered body is
Steam containing at least one type of reducing agent such as normal or ammonium nitrate at a temperature of 200°C or less after being immersed in a semiconductor mother liquor containing at least one type of reducing agent such as normal or ammonium nitrate, urea, formic acid, and alcohols. It is thermally decomposed in an atmosphere to form a semiconductor layer even outside the sintered body. At this time, the low thermal decomposition temperature prevents the semiconductor liquid from scattering, making subsequent welding of the terminals easier.
Also, since a homogeneous and uniform semiconductor layer is formed on the outside, loss is improved as a whole and leakage current characteristics are improved.

なお、還元剤は、低温熱分解において熱分解の反応を促
進ｒＪ−る作用を有し、製造効率を向上させる。Note that the reducing agent has the effect of accelerating the thermal decomposition reaction in low-temperature thermal decomposition, thereby improving production efficiency.

なお、低温の蒸気雰囲気中で熱分解を行なうと、通常、
容量が多少減少丈ることもあるが、本発明によれば、前
段において通常の高温の熱分解を行ない焼結体の内部に
微細な粒からなる半導体層を形成できるので、容量も十
分なものが得られる。Note that when thermal decomposition is performed in a low-temperature steam atmosphere,
Although the capacity may be slightly reduced, according to the present invention, a semiconductor layer made of fine grains can be formed inside the sintered body by performing normal high-temperature thermal decomposition in the first stage, so the capacity is still sufficient. is obtained.

次に、定格３５Ｖ１０μＦのタンタル固体電解コンデン
サについて、本発明によるものと従来例とについて各特
性を比較する。Next, the characteristics of tantalum solid electrolytic capacitors with a rating of 35 V and 10 μF will be compared between those according to the present invention and those of a conventional example.

先づ、弁作用金属としてタンタルの粉末を用い、この粉
末の焼結体をリン酸水溶液中に浸漬し１４０■の電圧を
印加して酸化し酸化皮膜を形成する。First, using tantalum powder as the valve metal, a sintered body of this powder is immersed in an aqueous phosphoric acid solution and oxidized by applying a voltage of 140 μm to form an oxide film.

次に１．陽極酸化皮膜形成後の焼結体を濃度４０〜６０
％の硝酸マンガン水溶液中に浸漬して液を含浸し、取り
出して温度２３０℃の蒸気雰囲気で熱分解する。以下こ
の含浸から熱分解までの工程を３回繰り返す。各工程を
３回繰り返した後、焼結体を硝ａ！２アンモンを少量添
加した硝酸マンガン水溶液中に浸漬し液を含浸して、温
度１９０℃の蒸気雰囲気中で熱分解し、以下３回繰り返
して半導体層を形成づる。熱分解後はリン酸水溶液中に
おいて再化成を行なう。後の工程は、従来通りであり、
カーボン層並びに銀層及び半田層からなる金属層を設け
てタンタル固体電解コンデンサを製造づ−る。Next 1. After forming the anodic oxide film, the sintered body has a concentration of 40 to 60.
% manganese nitrate aqueous solution to impregnate the liquid, then taken out and thermally decomposed in a steam atmosphere at a temperature of 230°C. Thereafter, the steps from impregnation to thermal decomposition are repeated three times. After repeating each process three times, the sintered body was made into a glass a! The semiconductor layer is immersed in a manganese nitrate aqueous solution to which a small amount of ammonium is added, and thermally decomposed in a steam atmosphere at a temperature of 190° C., and then repeated three times to form a semiconductor layer. After thermal decomposition, reconstitution is performed in an aqueous phosphoric acid solution. The subsequent steps are the same as before.
A tantalum solid electrolytic capacitor is manufactured by providing a carbon layer and a metal layer consisting of a silver layer and a solder layer.

従来のものは、焼結体を硝酸マンガン水溶液中←二浸酒
した後、１９０°Ｃの蒸気雰囲気中で熱分解する代わり
に、前段と同じ通常の熱分解を３回繰り返して製造する
。In the conventional method, instead of soaking the sintered body twice in an aqueous manganese nitrate solution and then thermally decomposing it in a steam atmosphere at 190°C, the same conventional thermal decomposition as the previous step is repeated three times.

上記の方法で製造した本発明にＪ：るものと従来のもの
とについて各々　１００個づつ、容量やｊａｎδ等の各
初期特性を測定し平均値を求めたところ表１の通りの結
果が得られた。１Ｊ−なわら、本発明による方が、ｔａ
ｎδは１３％減少し、個れ電流は７３％減少し、また、
容司は従来通りのものが得られ、各初期特性が改善され
ている。When we measured the initial characteristics such as capacity and jan δ of 100 pieces of each of the inventive and conventional products manufactured by the above method and calculated the average values, the results shown in Table 1 were obtained. Ta. 1J-However, the present invention has a better ta
nδ decreased by 13%, individual current decreased by 73%, and
Yoji is still the same as before, but each initial characteristic has been improved.

また、上記定格の各実施例について、耐湿性を測定した
ところ表２の通りの結果が得られた。耐湿試験は、ＰＣ
Ｔで温度１２０℃、２気圧、４　ＨＶの条件とし、各２
０ケづつ行なった。Ｊ′なわち、本発明による方が、従
来例に比べ、容量変化率は１１％、ｔａｎδ変化率は２
０％、漏れ電流変化率は６０％各々減少しており、耐湿
性についても各特性が改善されている。Further, when the moisture resistance of each of the examples with the above ratings was measured, the results shown in Table 2 were obtained. Humidity test is PC
T, temperature 120℃, 2 atmospheres, 4 HV conditions, each 2
I did 0 pieces at a time. J', that is, the capacitance change rate is 11% and the tan δ change rate is 2% compared to the conventional example according to the present invention.
The leakage current change rate was reduced by 0% and 60%, and the moisture resistance was also improved.

以上の通り、本発明によれば、端子の溶接作泉が容易に
なるのみならず、容量や損失、漏れ電流の各初期特性や
耐湿性の改善された固体電解コンデンサの製造方法が得
られる。As described above, according to the present invention, it is possible to obtain a method for manufacturing a solid electrolytic capacitor that not only facilitates welding of terminals but also improves initial characteristics such as capacity, loss, leakage current, and moisture resistance.

７５75

Claims (3)

【特許請求の範囲】[Claims] （１）　　弁作用金属の粉末からなる焼結体に陽極酸化
皮膜、半導体層、カーボン層及び金属層を順次段番プだ
固体電解コンデンサの製造方法において、＠極耐化皮膜
形成後の焼結体を半導体母液に浸漬した後、温度２００
”０〜３５０℃の蒸気雰囲気中で熱分解し、次に、温度
２００℃以下の蒸気雰囲気中で熱分解して半導体層を設
けることを特徴とする固体電解コンデンサの製造方法。(1) In a method for manufacturing a solid electrolytic capacitor, in which an anodized film, a semiconductor layer, a carbon layer, and a metal layer are sequentially applied to a sintered body made of valve metal powder, @sintering after the formation of an extremely resistant film After the body is immersed in the semiconductor mother liquor, the temperature is 200℃.
``A method for producing a solid electrolytic capacitor, which comprises thermally decomposing it in a steam atmosphere at a temperature of 0 to 350°C, and then thermally decomposing it in a steam atmosphere at a temperature of 200°C or less to provide a semiconductor layer. （２）　　弁作用金属の粉末からなる焼結体に陽極酸化
皮膜、半導体層、カーボン層及び金属層を順次設けた固
体電解コンデンサの製造方法において、陽極酸化皮膜形
成後の焼結体を半導体母液中に浸漬して温度２ｏｏ℃〜
３５０℃の蒸気雰囲気中において熱分解した後、硝酸ア
ンモンや尿素、ギ酸及びアルコール類等の還元剤が少な
（とも一種類添加された半導体母液中に浸漬し温度２０
０℃以下の蒸気雰囲気中において熱分解して半導体層を
設りることを特徴とする固体電解コンデンサの製造方法
。(2) In a method for producing a solid electrolytic capacitor in which an anodized film, a semiconductor layer, a carbon layer, and a metal layer are sequentially provided on a sintered body made of valve metal powder, the sintered body after the anodized film is formed is mixed with a semiconductor mother liquor. Immerse it in the temperature 2oo℃~
After thermal decomposition in a steam atmosphere at 350°C, it is immersed in a semiconductor mother liquor containing a small amount of reducing agents such as ammonium nitrate, urea, formic acid, and alcohols, and heated to a temperature of 20°C.
A method for manufacturing a solid electrolytic capacitor, which comprises forming a semiconductor layer by thermal decomposition in a steam atmosphere at a temperature of 0° C. or lower. （３）弁作用金属の粉末からなる焼結体に陽極酸化皮膜
、半導体層、カーボン層及び金属層を順次設けた固体電
解コンデンサの製造方法にａ５いて、陽極酸化皮膜形成
後の焼結体を半導体母液中に浸漬し温度２００℃〜３５
０℃の熱気雰囲気中において熱分解し、次に、硝酸アン
モン、尿素、ギ酸及びアルコール類等の還元剤を少なく
とも一種類含む温度２００℃以下の蒸気雰囲気中におい
て熱分解し半導体層を設けることを特徴とする固体電解
コンデンサの製造方法。(3) In the method for producing a solid electrolytic capacitor in which an anodized film, a semiconductor layer, a carbon layer, and a metal layer are sequentially provided on a sintered body made of valve metal powder, the sintered body after the anodic oxide film is formed is Immersed in semiconductor mother liquor at a temperature of 200°C to 35°C
The semiconductor layer is formed by thermal decomposition in a hot air atmosphere at 0°C, and then thermal decomposition in a steam atmosphere at a temperature of 200°C or lower containing at least one reducing agent such as ammonium nitrate, urea, formic acid, and alcohols. Features: Manufacturing method of solid electrolytic capacitors.