JPH07183174A - Electrolytic solution for driving electrolytic capacitors - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an electrolytic capacitor in which the boehmite reaction of a cathode aluminum foil is suppressed without increasing the specific resistance and the reliability is improved. [Structure] A solvent consisting of ethylene glycol and water, succinic acid, adipic acid, azelaic acid, sebacic acid, 1,
6 Sodium consisting of salts of organic carboxylic acids such as salts of decanedicarboxylic acid, maleic acid and citraconic acid, and one or more additives of arabite, galactit, adnit and xylit, and this additive Is 0.0
An electrolytic solution for driving an electrolytic capacitor, which is 1 to 10% by weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic solution for driving an electrolytic capacitor.

[0002]

2. Description of the Related Art Generally, an electrolytic solution having a low specific resistance value and stable characteristics over a wide temperature range is used as an electrolytic solution for driving an electrolytic capacitor. In an electrolytic solution containing ethylene glycol and water as a solvent and a salt of an organic carboxylic acid as a solute, the proportion of water is increased in order to reduce the resistance. Gas generation occurs due to the boehmite reaction of the cathode aluminum foil, and the explosion-proof valve operates, especially at high temperatures, resulting in low reliability.

[0003]

As described above, in the driving electrolyte solution using ethylene glycol and water as the solvent and the salt of the organic carboxylic acid as the solute, the gas due to the boehmite reaction that occurs in the cathode aluminum foil due to the presence of water. However, there is a drawback that gas is generated particularly at high temperatures, and a solution to this problem has been desired.

The present invention solves the above problems and suppresses gas generation due to the boehmite reaction of the cathode aluminum foil without increasing the specific resistance and improves the reliability of the electrolytic capacitor driving electrolytic solution. The purpose is to provide.

[0005]

The electrolytic solution for driving an electrolytic capacitor according to the present invention comprises a solvent composed of ethylene glycol and water, a solute composed of a salt of an organic carboxylic acid, an arabite, a galactit, an adnit and a xylit. It consists of one or more additives, and this additive is 0.0
It is composed of 1 to 10% by weight.

[0006]

According to the electrolytic capacitor driving electrolytic solution configured as described above, one or two of arabite, galactit, adonite, and xylit are contained even if a large amount of water is contained to reduce the resistance. By adding more than one species,
The boehmite reaction of the cathode aluminum foil can be suppressed without increasing the specific resistance. In particular, since it is effective in suppressing gas generation at high temperatures, stable performance can be obtained in a wide temperature range, and the reliability of the electrolytic capacitor can be significantly improved.

[0007]

EXAMPLES Examples of the present invention will be described below.

(Example A) As shown in Table 1 below, an electrolytic solution was prepared which is composed of an example and a comparative example in which the ratio of arabite added to the driving electrolytic solution is changed, and a conventional example in which no arabite is added. The specific resistance and spark voltage at 25 ° C. of each electrolytic solution were measured.

[0009]

[Table 1]

As is clear from Table 1, in Examples 1 and 2, no increase in resistivity or decrease in spark voltage was observed.

Next, the examples shown in Table 1 above, comparative examples,
Capacitance, tan δ, initial characteristics of leakage current and characteristics after high temperature load test (105 ° C, 1000 hours), gas generation amount, valve operation number of an aluminum electrolytic capacitor manufactured by using a driving electrolytic solution of a conventional example Table 2 and Table 3 show the results of the investigation.

The samples are 10 electrolytic capacitors each rated at 250 V-47 μF.

[0013]

[Table 2]

[0014]

[Table 3]

As is clear from Tables 2 and 3, the difference between the initial values of Examples 1 and 2 and the conventional example is small, but in the conventional example after the high temperature load test, gas generation due to the boehmite reaction of the cathode aluminum foil. Because of this, all valves are operating.
Further, in Comparative Example 1 in which the amount of added arabite was as small as 0.005% by weight, the number of valves that could not operate to suppress gas generation after the high temperature load test was large, and the amount of added arabite was as large as 15% by weight. In Comparative Example 2, the capacitance change rate and t
The value of an δ is large.

(Example B) In the above (Example A), the case where arabite was used as an additive was described.
In this (Example B), the case where galactit is used will be described. A sample similar to (Example A) except that galactit was used as an additive was prepared and tested.

[0017]

[Table 4]

As is clear from Table 4, no increase in resistivity or decrease in spark voltage was observed in Examples 3 and 4.
Then, Examples 3 and 4 and Comparative Example 3 shown in Table 4 above.
Rated 250V-4 produced by using the driving electrolyte of No. 4
7 μF electrolytic capacitors, 10 capacitors each, similar to (Example A), initial characteristics of capacitance, tan δ, leakage current, and characteristics after high temperature load test (105 ° C., 1000 hours), gas generation amount, number of valve operations Table 5 and Table 6
Shown in.

[0019]

[Table 5]

[0020]

[Table 6]

As can be seen from Tables 5 and 6, in Comparative Example 3 in which the amount of galactit added was as small as 0.005% by weight, the number of valves operated without suppressing the gas generation after the high temperature load test. The amount of galactit added is 15
In Comparative Example 4, which is as large as wt%, the capacitance change rate and tan δ
Has a large value and shows almost the same result as in (Example A).

(Example C) As the additive, the case of using arabite in (Example A) and the case of using galactit in (Example B) was described. In this (Example C), the case of using adnit is described. Samples similar to (Example A) and (Example B) were prepared and tested, except that Adnit was used as the additive.

[0023]

[Table 7]

As is clear from Table 7, no increase in the specific resistance and no decrease in the spark voltage were observed in Examples 5 and 6.
Then, Examples 5 and 6 and Comparative Example 5 shown in Table 7 above.
Rated 250V-4 produced by using the driving electrolyte of No. 6
7 μF electrolytic capacitors, 10 capacitors each, as in (Example A) and (Example B), initial characteristics of capacitance, tan δ, leakage current, and high temperature load test (105 ° C., 1000).
Tables 8 and 9 show the results of the investigation of the characteristics, the amount of gas generation, and the number of valve operations after (time).

[0025]

[Table 8]

[0026]

[Table 9]

As is clear from Tables 8 and 9, in Comparative Example 5 in which the amount of adnit added was as small as 0.005% by weight, the number of valves operating without suppressing the gas generation after the high temperature load test. In Comparative Example 6 in which the amount of addonite added was as large as 15% by weight, the capacitance change rate and the value of tan δ were large, and (Example A) and (Example B)
Shows almost the same result as.

(Example D) As an additive, arabite was used in (Example A), galactit was used in (Example B), and adnit was used in (Example C). The case where xylit is used will be described. Samples similar to (Example A), (Example B), and (Example C) were prepared and tested, except that xylite was used as the additive.

[0029]

[Table 10]

As is clear from Table 10, Examples 7 and 8
Also, no increase in resistivity or decrease in spark voltage was observed. Next, a rating of 250 was produced using the driving electrolytic solutions of Examples 7 and 8 and Comparative Examples 7 and 8 shown in Table 10 above.
Similar to (Example A), (Example B), and (Example C), for each of 10 V-47 μF electrolytic capacitors, initial characteristics of capacitance, tan δ, leakage current and high temperature load test (105 ° C., Tables 11 and 12 show the results of examining the characteristics, the amount of gas generated, and the number of valve operations after 1000 hours).

[0031]

[Table 11]

[0032]

[Table 12]

As is clear from Tables 11 and 12, Comparative Example 7 in which the amount of xylite added was as small as 0.005% by weight.
However, after the high temperature load test, the gas generation after the high temperature load test could not be suppressed, and the number of valve operations was large.
In Comparative Example 8 which is as large as wt%, the capacitance change rate and tan δ
Is larger, (Example A), (Example B)
And (Example C) show almost the same results.

In the above examples, ammonium sebacate was used as the solute, but succinic acid, adipic acid, azelaic acid, sebacic acid, 1,6
Similar effects can be obtained by using salts of decanedicarboxylic acid, maleic acid, and citraconic acid.

The case where arabite, galactit, adonite, and xylit are used alone as the additives has been described, but two or more of these additives are added in an amount of 0.01.
Similar effects can be obtained even when added in the range of 10 wt%.

[0036]

As described above, according to the electrolytic solution for driving an electrolytic capacitor of the present invention, a solution of ethylene glycol and water as a solvent and a salt of an organic carboxylic acid as a solute, arabite, galactit, and adnit are used. The tan δ and ESR can be reduced without increasing the specific resistance by adding one or more of the xylite. In addition, since the boehmite reaction that occurs in the cathode aluminum foil can be suppressed, it is possible to provide an electrolytic capacitor having a long life by suppressing the gas generation. This suppression of gas generation has a remarkable effect of improving the life characteristics especially at high temperatures.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 9, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic solution for driving an electrolytic capacitor.

[0002]

2. Description of the Related Art Generally, an electrolytic solution having a low specific resistance value and stable characteristics over a wide temperature range is used as an electrolytic solution for driving an electrolytic capacitor. In an electrolytic solution containing ethylene glycol and water as a solvent and a salt of an organic carboxylic acid as a solute, the proportion of water is increased in order to reduce the resistance. Gas generation occurs due to the boehmite reaction of the cathode aluminum foil, and the explosion-proof valve operates, especially at high temperatures, resulting in low reliability.

[0003]

As described above, in the driving electrolyte solution using ethylene glycol and water as the solvent and the salt of the organic carboxylic acid as the solute, the gas due to the boehmite reaction that occurs in the cathode aluminum foil due to the presence of water. However, there is a drawback that gas is generated particularly at high temperatures, and a solution to this problem has been desired.

The present invention solves the above problems and suppresses gas generation due to the boehmite reaction of the cathode aluminum foil without increasing the specific resistance and improves the reliability of the electrolytic capacitor driving electrolytic solution. The purpose is to provide.

[0005]

The electrolytic solution for driving an electrolytic capacitor according to the present invention comprises a solvent composed of ethylene glycol and water, a solute composed of a salt of an organic carboxylic acid, an arabite, a galactit, an adnit and a xylit. It consists of one or more additives, and this additive is 0.0
It is composed of 1 to 10% by weight.

[0006]

According to the electrolytic capacitor driving electrolytic solution configured as described above, one or two of arabite, galactit, adonite, and xylit are contained even if a large amount of water is contained to reduce the resistance. 0.01-1 more than one additive
By adding 0% by weight, the boehmite reaction of the cathode aluminum foil can be suppressed without increasing the specific resistance.
Especially effective in suppressing gas generation at high temperatures,
Stable performance can be obtained in a wide temperature range, and reliability of the electrolytic capacitor can be remarkably improved.

[0007]

EXAMPLES Examples of the present invention will be described below.

(Example A) As shown in Table 1 below, an electrolytic solution was prepared which is composed of an example and a comparative example in which the ratio of arabite added to the driving electrolytic solution is changed, and a conventional example in which no arabite is added. The specific resistance and spark voltage at 25 ° C. of each electrolytic solution were measured.

[0009]

[Table 1]

As is clear from Table 1, in Examples 1 and 2, no increase in resistivity or decrease in spark voltage was observed.

Next, the examples shown in Table 1 above, comparative examples,
Capacitance, tan δ, initial characteristics of leakage current and characteristics after high temperature load test (105 ° C, 1000 hours), gas generation amount, valve operation number of an aluminum electrolytic capacitor manufactured by using a driving electrolytic solution of a conventional example Table 2 and Table 3 show the results of the investigation.

The samples are 10 electrolytic capacitors each rated at 250 V-47 μF.

[0013]

[Table 2]

[0014]

[Table 3]

As is clear from Tables 2 and 3, the difference between the initial values of Examples 1 and 2 and the conventional example is small, but in the conventional example after the high temperature load test, gas generation due to the boehmite reaction of the cathode aluminum foil. Because of this, all valves are operating.
Further, in Comparative Example 1 in which the amount of added arabite was as small as 0.005% by weight, the number of valves that could not operate to suppress gas generation after the high temperature load test was large, and the amount of added arabite was as large as 15% by weight. In Comparative Example 2, the capacitance change rate and t
The value of an δ is large.

(Example B) In the above (Example A), the case where arabite was used as an additive was described.
In this (Example B), the case where galactit is used will be described. A sample similar to (Example A) except that galactit was used as an additive was prepared and tested.

[0017]

[Table 4]

As is clear from Table 4, no increase in resistivity or decrease in spark voltage was observed in Examples 3 and 4.
Then, Examples 3 and 4 and Comparative Example 3 shown in Table 4 above.
Rated 250V-4 produced by using the driving electrolyte of No. 4
7 μF electrolytic capacitors, 10 capacitors each, similar to (Example A), initial characteristics of capacitance, tan δ, leakage current and characteristics after high temperature load test (105 ° C., 1000 hours), gas generation amount, number of valve operations Table 5 and Table 6
Shown in.

[0019]

[Table 5]

[0020]

[Table 6]

As can be seen from Tables 5 and 6, in Comparative Example 3 in which the amount of galactit added was as small as 0.005% by weight, the number of valves operated without suppressing the gas generation after the high temperature load test. The amount of galactit added is 15
In Comparative Example 4, which is as large as wt%, the capacitance change rate and tan δ
Has a large value and shows almost the same result as in (Example A).

(Example C) As the additive, the case of using arabite in (Example A) and the case of using galactit in (Example B) was described. In this (Example C), the case of using adnit is described. Samples similar to (Example A) and (Example B) were prepared and tested, except that Adnit was used as the additive.

[0023]

[Table 7]

As is clear from Table 7, no increase in the specific resistance and no decrease in the spark voltage were observed in Examples 5 and 6.
Then, Examples 5 and 6 and Comparative Example 5 shown in Table 7 above.
Rated 250V-4 produced by using the driving electrolyte of No. 6
7 μF electrolytic capacitors, 10 capacitors each, as in (Example A) and (Example B), initial characteristics of capacitance, tan δ, leakage current, and high temperature load test (105 ° C., 1000).
Tables 8 and 9 show the results of the investigation of the characteristics, the amount of gas generation, and the number of valve operations after (time).

[0025]

[Table 8]

[0026]

[Table 9]

As is clear from Tables 8 and 9, in Comparative Example 5 in which the amount of adnit added was as small as 0.005% by weight, the number of valves operating without suppressing the gas generation after the high temperature load test. In Comparative Example 6 in which the amount of addonite added was as large as 15% by weight, the capacitance change rate and the value of tan δ were large, and (Example A) and (Example B)
Shows almost the same result as.

(Example D) As an additive, arabite was used in (Example A), galactit was used in (Example B), and adnit was used in (Example C). The case where xylit is used will be described. Samples similar to (Example A), (Example B), and (Example C) were prepared and tested, except that xylite was used as the additive.

[0029]

[Table 10]

As is clear from Table 10, Examples 7 and 8
Also, no increase in resistivity or decrease in spark voltage was observed. Next, a rating of 250 was produced using the driving electrolytic solutions of Examples 7 and 8 and Comparative Examples 7 and 8 shown in Table 10 above.
Similar to (Example A), (Example B), and (Example C), for each of 10 V-47 μF electrolytic capacitors, initial characteristics of capacitance, tan δ, leakage current and high temperature load test (105 ° C., Tables 11 and 12 show the results of examining the characteristics, the amount of gas generated, and the number of valve operations after 1000 hours).

[0031]

[Table 11]

[0032]

[Table 12]

As is clear from Tables 11 and 12, Comparative Example 7 in which the amount of xylite added was as small as 0.005% by weight.
However, after the high temperature load test, the gas generation after the high temperature load test could not be suppressed, and the number of valve operations was large.
In Comparative Example 8 which is as large as wt%, the capacitance change rate and tan δ
Is larger, (Example A), (Example B)
And (Example C) show almost the same results.

In the above examples, ammonium sebacate was used as a solute, but succinic acid, adipic acid, azelaic acid, sebacic acid, 1,6
Similar effects can be obtained by using salts of decanedicarboxylic acid, maleic acid, and citraconic acid.

The case where arabite, galactit, adonite, and xylit are used alone as the additives has been described, but two or more of these additives are added in an amount of 0.01.
Similar effects can be obtained even when added in the range of 10 wt%.

[0036]

As described above, according to the electrolytic solution for driving an electrolytic capacitor of the present invention, a solution of ethylene glycol and water as a solvent and a salt of an organic carboxylic acid as a solute, arabite, galactit, and adnit are used. , 0.01 to 10 layers of one or more additives in xylite
Addition of the amount of γ can reduce tan δ and ESR without increasing the specific resistance. In addition, since the boehmite reaction that occurs in the cathode aluminum foil can be suppressed, it is possible to provide an electrolytic capacitor having a long life by suppressing the gas generation. This suppression of gas generation has a remarkable effect of improving the life characteristics especially at high temperatures.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kiyoshi Sakamoto 1-1, Sachimachi, Nagai City, Yamagata Prefecture Marcon Electronics Co., Ltd. (72) Inventor, Kazuhiro Higuchi 1-1, Sachimachi, Nagai City, Yamagata Prefecture Marcon Electronics Co., Ltd. (72) Inventor Tetsuo Aoyama 182 Tayuhama Shinwari Niigata, Niigata Prefecture Mitsubishi Gas Chemical Co., Ltd. Niigata Research Center (72) Inventor Mayumi Haneda Tayuhama Shinwari 182 Niigata City, Niigata Mitsubishi Gas Chemical Co., Ltd. Niigata Research Center

Claims (1)

[Claims] 1. A solvent composed of ethylene glycol and water, a solute composed of a salt of an organic carboxylic acid, and arabite,
It is composed of one or more additives selected from galactit, adnit and xylit, and the additive is 0.01 to
An electrolytic solution for driving an electrolytic capacitor, which is 10% by weight.