JPH0410514A - Electrolyte for electrolytic capacitor - Google Patents
Electrolyte for electrolytic capacitorInfo
- Publication number
- JPH0410514A JPH0410514A JP11214490A JP11214490A JPH0410514A JP H0410514 A JPH0410514 A JP H0410514A JP 11214490 A JP11214490 A JP 11214490A JP 11214490 A JP11214490 A JP 11214490A JP H0410514 A JPH0410514 A JP H0410514A
- Authority
- JP
- Japan
- Prior art keywords
- mannitol
- sorbitol
- electrolytic capacitor
- phosphoric acid
- electrolyte
- 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.)
- Granted
Links
- 239000003990 capacitor Substances 0.000 title claims abstract description 15
- 239000003792 electrolyte Substances 0.000 title abstract description 10
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims abstract description 22
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims abstract description 11
- 230000005494 condensation Effects 0.000 claims abstract description 11
- 238000009833 condensation Methods 0.000 claims abstract description 11
- 229920000642 polymer Polymers 0.000 claims abstract description 11
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000004327 boric acid Substances 0.000 claims abstract description 9
- FBPFZTCFMRRESA-FSIIMWSLSA-N D-Glucitol Natural products OC[C@H](O)[C@H](O)[C@@H](O)[C@H](O)CO FBPFZTCFMRRESA-FSIIMWSLSA-N 0.000 claims abstract description 8
- FBPFZTCFMRRESA-KVTDHHQDSA-N D-Mannitol Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-KVTDHHQDSA-N 0.000 claims abstract description 8
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 claims abstract description 8
- 229930195725 Mannitol Natural products 0.000 claims abstract description 8
- 239000000594 mannitol Substances 0.000 claims abstract description 8
- 229960001855 mannitol Drugs 0.000 claims abstract description 8
- 235000010355 mannitol Nutrition 0.000 claims abstract description 8
- 239000000600 sorbitol Substances 0.000 claims abstract description 8
- 229960002920 sorbitol Drugs 0.000 claims abstract description 8
- 235000010356 sorbitol Nutrition 0.000 claims abstract description 8
- 239000002904 solvent Substances 0.000 claims abstract description 5
- 150000005846 sugar alcohols Polymers 0.000 claims abstract description 5
- 239000004386 Erythritol Substances 0.000 claims abstract description 4
- UNXHWFMMPAWVPI-UHFFFAOYSA-N Erythritol Natural products OCC(O)C(O)CO UNXHWFMMPAWVPI-UHFFFAOYSA-N 0.000 claims abstract description 4
- SQUHHTBVTRBESD-UHFFFAOYSA-N Hexa-Ac-myo-Inositol Natural products CC(=O)OC1C(OC(C)=O)C(OC(C)=O)C(OC(C)=O)C(OC(C)=O)C1OC(C)=O SQUHHTBVTRBESD-UHFFFAOYSA-N 0.000 claims abstract description 4
- 235000019414 erythritol Nutrition 0.000 claims abstract description 4
- UNXHWFMMPAWVPI-ZXZARUISSA-N erythritol Chemical compound OC[C@H](O)[C@H](O)CO UNXHWFMMPAWVPI-ZXZARUISSA-N 0.000 claims abstract description 4
- 229940009714 erythritol Drugs 0.000 claims abstract description 4
- CDAISMWEOUEBRE-GPIVLXJGSA-N inositol Chemical compound O[C@H]1[C@H](O)[C@@H](O)[C@H](O)[C@H](O)[C@@H]1O CDAISMWEOUEBRE-GPIVLXJGSA-N 0.000 claims abstract description 4
- 229960000367 inositol Drugs 0.000 claims abstract description 4
- CDAISMWEOUEBRE-UHFFFAOYSA-N scyllo-inosotol Natural products OC1C(O)C(O)C(O)C(O)C1O CDAISMWEOUEBRE-UHFFFAOYSA-N 0.000 claims abstract description 4
- 150000003839 salts Chemical class 0.000 claims abstract description 3
- 239000008151 electrolyte solution Substances 0.000 claims description 9
- 150000003014 phosphoric acid esters Chemical class 0.000 claims description 5
- 230000006866 deterioration Effects 0.000 abstract description 2
- 238000000034 method Methods 0.000 abstract description 2
- -1 phosphate ester Chemical class 0.000 abstract description 2
- 229910019142 PO4 Inorganic materials 0.000 abstract 1
- 150000002148 esters Chemical class 0.000 abstract 1
- 239000010452 phosphate Substances 0.000 abstract 1
- 229920000137 polyphosphoric acid Polymers 0.000 abstract 1
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- WYXIGTJNYDDFFH-UHFFFAOYSA-Q triazanium;borate Chemical compound [NH4+].[NH4+].[NH4+].[O-]B([O-])[O-] WYXIGTJNYDDFFH-UHFFFAOYSA-Q 0.000 description 4
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 150000002828 nitro derivatives Chemical class 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- QUJSFPXBUIZZAC-UHFFFAOYSA-N boric acid;ethane-1,2-diol Chemical compound OCCO.OB(O)O QUJSFPXBUIZZAC-UHFFFAOYSA-N 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
- Primary Cells (AREA)
Abstract
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は電解コンデンサ用電解液に関する。[Detailed description of the invention] (Industrial application field) The present invention relates to an electrolytic solution for electrolytic capacitors.
（従来の技術）
従来のエチレングリコールなどの多価アルコール類にホ
ウ酸やホウ酸アンモニウムを溶解した電解液は一中高圧
用のアルミニウム電解コンデンサに用いられている。こ
れは、ホウ酸か゛アルミニウム酸化皮膜に対して安定な
弱酸であり、耐電圧を向上でき、しかも有機酸を溶質と
する電解液では得られない離燃性が得られることによる
。このため、特に安全性の要求される高圧大容量のコン
デンサに用いられることが多い。(Prior Art) Conventional electrolytes in which boric acid or ammonium borate are dissolved in polyhydric alcohols such as ethylene glycol are used in aluminum electrolytic capacitors for medium to high voltage applications. This is because boric acid is a weak acid that is stable against aluminum oxide films, can improve withstand voltage, and provides combustibility that cannot be obtained with electrolytes containing organic acids as solutes. For this reason, they are often used in high-voltage, large-capacity capacitors that particularly require safety.
しかし、この従来の電解液は、一般に液中の水分が多く
、陽極箔に形成した誘電体酸化皮膜を劣化させ、漏れ電
流（以下ＬＣと略す）を増大させる。このために、高温
下において水素カス発生盆か大きく、短期間で内月か上
昇し、ゲースの膨脹、防爆弁の作動を生じる問題かある
。この問題を解決するために、特公昭４９−１４３００
号や特公昭５３−４２１１０号に示す通りニトロ化合物
を水素ガス吸収剤として添加したり、リン酸を誘電体酸
化皮膜の耐水性を向上させるために添加したりしている
。However, this conventional electrolytic solution generally contains a large amount of water, which deteriorates the dielectric oxide film formed on the anode foil and increases leakage current (hereinafter abbreviated as LC). For this reason, there is a problem in that the hydrogen scum generation basin is large under high temperatures, and the internal mass rises in a short period of time, causing expansion of the gas and activation of the explosion-proof valve. In order to solve this problem,
As shown in Japanese Patent Publication No. 53-42110, a nitro compound is added as a hydrogen gas absorbent, and phosphoric acid is added to improve the water resistance of a dielectric oxide film.
（発明が解決しようとする課題）
しかし、ニトロ化合物やリン酸を添加しても高温下にお
いて、各々の効果を長期間維持できず、長期間放置後に
ＬＣが増大したり、ｔａｎδの経時変化か大きくなる欠
点がある。(Problem to be solved by the invention) However, even if nitro compounds and phosphoric acid are added, their respective effects cannot be maintained for a long period of time at high temperatures, and LC increases after being left for a long period of time, and tan δ changes over time. The disadvantage is that it gets bigger.
また、電解液中のニトロ化合物等の添加量か多くなると
漏れ電流が増大し、微量の場合には抑制効果が低く、製
造が困雛である欠点かある。In addition, if the amount of nitro compound added to the electrolytic solution increases, the leakage current increases, and if the amount is small, the suppressing effect is low and manufacturing is difficult.
本発明の目的は、以上の欠点を改良し、ＬＣ特性やｔａ
ｎδ特性を向上でき、製造の容易な電解コンデンサ用電
解液を提供するものである。The purpose of the present invention is to improve the above-mentioned drawbacks and improve the LC characteristics and ta.
An object of the present invention is to provide an electrolytic solution for an electrolytic capacitor that can improve nδ characteristics and is easy to manufacture.
（課題を解決するための手段）
本発明は、上記の目的を達成するために、多価アルコー
ルを主成分とする溶媒と、ホウ酸またはその塩のうち少
なくとも１種を溶質とする電解コンデンサ用電解液にお
いて、リン酸の縮重合体またはリン酸エステルの縮重合
体のうち少なくとも１種と、マンニトール、ソルビトー
ル、エリスリトールまたはイノシトールのうち少なくと
も１種とを溶解することを特徴とする電解コンデンサ用
電解液を提供するものである。(Means for Solving the Problems) In order to achieve the above object, the present invention provides an electrolytic capacitor containing a solvent containing polyhydric alcohol as a main component and at least one of boric acid or a salt thereof as a solute. An electrolytic solution for an electrolytic capacitor, characterized in that at least one kind of a condensation polymer of phosphoric acid or a condensation polymer of phosphoric acid ester and at least one kind of mannitol, sorbitol, erythritol or inositol are dissolved in the electrolytic solution. It provides liquid.
（作用）
リン酸またはリン酸エステルの縮重合体はリン酸に比べ
て、アルミニウムイオンと反応してＷｂ ’Ｆｆｉ表面
により緻密な保護膜を形成し、そのために、耐水性が向
上し、カス発生が抑制される。特に、エチレングリコー
ル−ホウ酸系電解液は水分量が多いが、この電解液にリ
ン酸等の縮重合体を添加すると、アルミニウム電極の溶
解を低下でき、従って、アルミニウム電極と電解液との
間に生じる局部電池作用をおさえることができ、この作
用を原因とするガス発生も低減できるとともに電圧印加
時のＬＣも低下できる。(Function) Compared to phosphoric acid, the condensation polymer of phosphoric acid or phosphoric acid ester reacts with aluminum ions to form a denser protective film on the Wb'Ffi surface, improving water resistance and reducing scum generation. is suppressed. In particular, ethylene glycol-boric acid electrolyte has a high water content, but adding a condensation polymer such as phosphoric acid to this electrolyte can reduce the dissolution of the aluminum electrode, thereby increasing the amount of water between the aluminum electrode and the electrolyte. It is possible to suppress the local cell effect that occurs in the process, reduce the gas generation caused by this effect, and also reduce the LC when voltage is applied.
また、リン酸等の縮重合体を比較的に多量に添加しても
火花電圧の低下やＬＣの増大をおさえられる。Further, even if a relatively large amount of a condensation polymer such as phosphoric acid is added, a decrease in spark voltage and an increase in LC can be suppressed.
さらに、マンニトールやソルビトール等は、ホウ酸等と
反応して錯体を形成するために、高温下において安定し
、ＬＣ特性やｔａｎδ特性を改良できる。Furthermore, since mannitol, sorbitol, and the like react with boric acid and the like to form a complex, they are stable at high temperatures and can improve LC characteristics and tan δ characteristics.
（実施例） 以下、本発明を実施例に基づいて説明する。(Example) Hereinafter, the present invention will be explained based on examples.
溶媒は、エチレングリコールやジエチレングリコール等
の多価アルコール類を用いる。Polyhydric alcohols such as ethylene glycol and diethylene glycol are used as the solvent.
溶質にはホウ酸またはホウ酸アンモニウムを用いる。Boric acid or ammonium borate is used as the solute.
そしてこの溶媒と溶質とからなる液に次の構造式からな
るリン酸の縮重合体またはリン酸エステルの縮重合体の
うち少なくとも１種を溶解する。Then, at least one kind of a condensation polymer of phosphoric acid or a condensation polymer of phosphoric acid ester having the following structural formula is dissolved in the liquid consisting of the solvent and the solute.
添加量は、０．０１〜１０．０ｗｔ％がよく、０゜０１
ｗｔ％未満では効果が低く、１０．０１％を越えると火
花電圧か低下し易い。The amount added is preferably 0.01 to 10.0 wt%, and 0°01
If it is less than 10.01% by weight, the effect is low, and if it exceeds 10.01%, the spark voltage tends to decrease.
負荷試験条件は、温度１１０°Ｃ５印加電圧４００Ｖ、
ＤＣとする。ＬＣの値は、試料を温度２０°Ｃの雰囲気
中に２４ｈｒ放置後、定格電圧を印加し、５分後の測定
値とする。測定結果は表２の通りとなった。The load test conditions were: temperature 110°C, applied voltage 400V,
DC. The LC value is the value measured 5 minutes after leaving the sample in an atmosphere at a temperature of 20° C. for 24 hours, applying the rated voltage. The measurement results are shown in Table 2.
以下余白。Margin below.
また、マンニトールやソルビトール、エリスリトール、
イノシトールのうち少なくとも１種を溶解する。In addition, mannitol, sorbitol, erythritol,
At least one kind of inositol is dissolved.
次に、上記実施例と従来例の電解液をコンデンサ素子に
含浸した定格４５０■、３３０μＦのアルミ電解コンデ
ンサを用いて、高温負荷試験を行ない、ＬＣ及びｔａｎ
δを測定した。Next, a high-temperature load test was conducted using aluminum electrolytic capacitors with a rating of 450 μF and 330 μF in which the capacitor elements were impregnated with the electrolytes of the above example and the conventional example, and the LC and tan
δ was measured.
電解液の組成は表１の通りとする。また−高温表２から
明らかな通り、ホウ酸アンモニウムのみを溶質として用
いた場合を比べると、３０００ｈｒ放置後、実施例１〜
実施例１０及び実施例１２が８５〜１３０μＡ、従来例
１〜従来例６が１３０〜３６５μＡとなり、前者の方が
後者よりも全体的に低い値となっている。また、ｔａｎ
δについても、実施例１〜実施例１０及び実施例１２が
０゜０７８〜０．１１２、従来例１〜従来例６が０１０
１〜０．１７３となり、同様に前者の方が低い値におさ
えられている。The composition of the electrolyte is as shown in Table 1. In addition, as is clear from Table 2, when ammonium borate alone is used as a solute, after standing for 3000 hours, Examples 1 to
Examples 10 and 12 have values of 85 to 130 μA, and Conventional Examples 1 to 6 have values of 130 to 365 μA, with the former being lower overall than the latter. Also, tan
As for δ, Examples 1 to 10 and Example 12 are 0°078 to 0.112, and Conventional Examples 1 to 6 are 0°010.
1 to 0.173, and similarly the former is kept to a lower value.
ホウ酸アンモニウムとホウ酸を溶質として用いた実施例
１１と従来例７とについても、３０００ｈｒ放置後のＬ
Ｃ及びｔａｎδは、前者の方が後者よりも低くおさえら
れ、各々９／１１．１４／１７となっている。Regarding Example 11 and Conventional Example 7 in which ammonium borate and boric acid were used as solutes, the L
C and tan δ were kept lower in the former than in the latter, being 9/11 and 14/17, respectively.
（発明の効果）
以上の通り、本発明によれば、リン酸やリン酸エステル
の縮重合体と併せて、マンニトールやソルビトール等を
溶解しているために、電解コンデンサを高温下に放置し
た場合のＬＣやｔａｎδの劣化を抑制でき、 製造の容
易な電解コンデンサ用電解液が得られる。(Effects of the Invention) As described above, according to the present invention, since mannitol, sorbitol, etc. are dissolved together with phosphoric acid and a condensation polymer of phosphoric acid ester, when an electrolytic capacitor is left under high temperature An electrolytic solution for electrolytic capacitors that can suppress deterioration of LC and tan δ and is easy to manufacture can be obtained.
Claims (1)
たはその塩のうち少なくとも１種を溶質とする電解コン
デンサ用電解液において、リン酸の縮重合体またはリン
酸エステルの縮重合体のうち少なくとも１種と、マンニ
トール、ソルビトール、エリスリトールまたはイノシト
ールのうち少なくとも１種とを溶解することを特徴とす
る電解コンデンサ用電解液。(1) In an electrolytic solution for electrolytic capacitors containing a solvent mainly composed of polyhydric alcohol and at least one of boric acid or its salt as a solute, a condensation polymer of phosphoric acid or a condensation polymer of phosphoric acid ester is used. An electrolytic solution for an electrolytic capacitor, characterized in that at least one of these and at least one of mannitol, sorbitol, erythritol, or inositol are dissolved.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2112144A JPH0748459B2 (en) | 1990-04-27 | 1990-04-27 | Electrolytic solution for electrolytic capacitors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2112144A JPH0748459B2 (en) | 1990-04-27 | 1990-04-27 | Electrolytic solution for electrolytic capacitors |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0410514A true JPH0410514A (en) | 1992-01-14 |
| JPH0748459B2 JPH0748459B2 (en) | 1995-05-24 |
Family
ID=14579326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2112144A Expired - Lifetime JPH0748459B2 (en) | 1990-04-27 | 1990-04-27 | Electrolytic solution for electrolytic capacitors |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0748459B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06151253A (en) * | 1992-11-13 | 1994-05-31 | Hitachi Aic Inc | Electrolyte for electrolytic capacitor |
| JPH06204091A (en) * | 1992-12-29 | 1994-07-22 | Hitachi Aic Inc | Electrolyte for electrolytic capacitor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01114020A (en) * | 1987-10-28 | 1989-05-02 | Matsushita Electric Ind Co Ltd | Electrolyte for driving electrolytic capacitor |
| JPH01128418A (en) * | 1987-11-12 | 1989-05-22 | Hitachi Condenser Co Ltd | Electrolytic solution for electrolytic capacitor |
-
1990
- 1990-04-27 JP JP2112144A patent/JPH0748459B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01114020A (en) * | 1987-10-28 | 1989-05-02 | Matsushita Electric Ind Co Ltd | Electrolyte for driving electrolytic capacitor |
| JPH01128418A (en) * | 1987-11-12 | 1989-05-22 | Hitachi Condenser Co Ltd | Electrolytic solution for electrolytic capacitor |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06151253A (en) * | 1992-11-13 | 1994-05-31 | Hitachi Aic Inc | Electrolyte for electrolytic capacitor |
| JPH06204091A (en) * | 1992-12-29 | 1994-07-22 | Hitachi Aic Inc | Electrolyte for electrolytic capacitor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0748459B2 (en) | 1995-05-24 |
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