JP2910076B2 - Electrolyte for driving electrolytic capacitors - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic solution for driving an electrolytic capacitor used for an electrolytic capacitor for medium and high pressures.

2. Description of the Related Art As a conventional electrolytic solution for driving an electrolytic capacitor, particularly as a medium-to-high pressure electrolytic solution, as shown in Japanese Patent Publication No. 60-13293, there is an example in which butyloctane diacid is used as a solute. As seen in 15738, there are many examples of using 5,6-decanedicarboxylic acid as a solute, but in these cases, there is a change in specific resistance over a long period of time at a high temperature, and the specific resistance at a low temperature deteriorates. was there.
In order to solve such drawbacks, the main solvent is γ-butyrolactone, and by using these dibasic acids or salts thereof, the ester does not undergo an ester degradation reaction even at a high temperature, and the resistivity changes even at a low temperature. It becomes a driving electrolyte that is difficult to perform.

Problems to be Solved by the Invention However, by using these dibasic acids or salts thereof in a solvent mainly composed of γ-butyrolactone, it was good in that the change in specific resistance was difficult, but it was good for constant current formation. There is a disadvantage that the formation / discharge characteristics (hereinafter referred to as spark generation voltage) at the time are not sufficient.

An object of the present invention is to solve such a conventional drawback, and an object of the present invention is to provide an electrolytic solution for driving an electrolytic capacitor for medium and high pressures in which a spark generation voltage is sufficiently increased.

Means for Solving the Problems To solve the above problems, the electrolytic solution for driving an electrolytic capacitor of the present invention comprises a solvent mainly composed of γ-butyrolactone, 1-methyl-1,7-heptanedicarboxylic acid, 1,7 -Dimethyl-1,7-heptanedicarboxylic acid, 1,3-dimethyl-
1,3,9-nonanetricarboxylic acid, 1,3-dimethyl-3-carbomethoxy-1,9-nonanedicarboxylic acid, 1,3-dimethyl-1,7-heptanedicarboxylic acid, 1-methyl-3-ethyl -1,7-heptanedicarboxylic acid, 7-ethyl-1,16
-Hexadecanedicarboxylic acid, 7,8,11,12-tetramethyl-1,18-octadecanedicarboxylic acid, 7,8-dimethyl-1,14-tetradecanedicarboxylic acid, 1-methyl-1,6
-Hexanedicarboxylic acid, 1,3-dimethyl-3-carbomethoxy-1,8-octanedicarboxylic acid, 1,3-dimethyl-1,3,8-octanetricarboxylic acid, 1-methyl-1,8-
Octanedicarboxylic acid, 1,3-dimethyl-3-carbomethoxy-1,10-decanedicarboxylic acid, 1,3-dimethyl-
1,3,10-decanetricarboxylic acid, 7-phenyl-7-methoxy-1-octanecarboxylic acid, 6-phenyl-6-
Methoxy-heptanecarboxylic acid, an acid selected from 6-ethyl-1,14-tetradecanedicarboxylic acid, or one or more of its salts as a main solute,
In addition, one or more of orthophosphoric acid, phosphorous acid and alkyl phosphoric acid esters are added and dissolved.

Examples of the salt include an ammonium salt, a secondary amine salt, a tertiary amine salt, and a quaternary ammonium salt. Specific examples of the secondary amine salt include dimethylamine salt, diethylamine salt, and dipropylamine. Salt, dibutylamine salt, methylethylamine salt, methylpropylamine salt, methylbutylamine salt, ethylpropylamine salt, ethylbutylamine salt, propylbutylamine salt. Specific examples of the tertiary amine salt include trimethylamine salt, dimethylethylamine salt, dimethylpropylamine salt, dimethylbutylamine salt, diethylmethylamine salt, methylethylpropylamine salt, methylethylbutylamine salt, dipropylmethylamine salt, methyl Propylbutylamine salt, dibutylmethylamine salt, triethylamine salt, diethylpropylamine salt,
Diethylbutylamine salt, dipropylethylamine salt,
Ethylpropylbutylamine salt, dibutylethylamine salt, tripropylamine salt, dipropylbutylamine salt, dibutylpropylamine salt, tributylamine salt. Specific examples of the quaternary ammonium salt include tetramethylammonium salt, trimethylethylammonium salt, trimethylpropylammonium salt, trimethylbutylammonium salt, dimethyldiethylammonium salt, dimethylethylpropylammonium salt, dimethylethylbutylammonium salt, and dimethylethylammonium salt. Dipropyl ammonium salt, dimethylpropyl butyl ammonium salt, dimethyl dibutyl ammonium salt, triethyl methyl ammonium salt, diethyl methyl propyl ammonium salt, diethyl methyl butyl ammonium salt, dipropyl methyl ethyl ammonium salt, methyl ethyl propyl butyl ammonium salt, dibutyl methyl ethyl Ammonium salt, tripropylmethylammonium salt, dipropylmethylbutylammonium Salt, dibutylmethylpropylammonium salt, tributylmethylammonium salt, tetraethylammonium salt, triethylpropylammonium salt, triethylbutylammonium salt, diethyldipropylammonium salt, diethylpropylbutylammonium salt, diethyldibutylammonium salt, tripropylethylammonium salt , Dipropylethylbutylammonium salt, dibutylethylpropylammonium salt, tributylethylammonium salt, tetrapropylammonium salt, tripropylbutylammonium salt, dipropyldibutylammonium salt, and tributylpropylammonium salt.

The structural formula of the acid used in the present invention is as follows.

Action The acid used in the electrolytic solution for driving the electrolytic capacitor of the present invention described above is superior in chemical conversion properties as compared with butyloctane diacid and 5,6-decanedicarboxylic acid. In addition to the above, by adding orthophosphoric acid, phosphorous acid, and alkyl phosphate esters having good oxide film repair performance at the defective portion, the spark generation voltage can be further increased.

Examples Hereinafter, examples of the present invention will be described. Table 1 shows a comparison of characteristics between the conventional example and the example of the present invention with respect to composition, specific resistance, spark generation voltage, and water content.

Among the electrolytes shown in Table 1, Conventional Examples 2 and 3 and Examples
Table 2 shows the results of a high-temperature ripple test performed at a temperature of 110 ° C. for 1000 hours for each of 30 electrolytic capacitors (rated at 400 V and 270 μF) using 1,19,20,21,22 electrolytic solutions. However,
The product was aged at 430 V for 2 hours.

As is clear from Table 1, the electrolytes of Examples 1 to 22 of the present invention have a feature that the spark generation voltage is higher than those of the electrolytes of Conventional Examples 2 and 3, and therefore the products shown in Table 2 In the tests, the conventional examples 2 and 3 show short-circuiting during aging, but the examples 1, 19, 20, 21, and 22 show no short-circuiting during aging and during testing. It can be seen that the electrolytic solution was excellent. In addition, since there is little change in any of the characteristics such as the rate of change in capacitance, the change in tan δ, and the change in appearance, a highly reliable electrolytic capacitor can be obtained.

FIG. 1 shows the formation and discharge characteristics of the present invention and the conventional electrolytic solution for driving an electrolytic capacitor at the time of constant current formation. In this comparison, the present invention is also superior. it is obvious.

Advantages of the Invention As is apparent from the above description of the embodiment, according to the present invention, it is possible to obtain an electrolytic solution for driving an electrolytic capacitor for medium and high pressures with a high spark generation voltage. In addition, since γ-butyrolactone can be used as the main solvent, it is possible to provide an extremely reliable medium-to-high pressure electrolytic capacitor with little change in characteristics.

[Brief description of the drawings]

FIG. 1 is a characteristic diagram showing a comparison of formation / discharge characteristics during constant current formation between an electrolytic solution for driving an electrolytic capacitor according to an embodiment of the present invention and an electrolytic solution for driving an electrolytic capacitor according to a conventional example.

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Keiji Mori 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-62-254416 (JP, A) JP-A-63-268225 (JP, A) JP-A-63-261822 (JP, A) (58) Fields studied (Int. ⁶ , DB name) H01G 9/035

Claims (10)

(57) [Claims] (1) a solvent mainly composed of γ-butyrolactone,
1-methyl-1,7-heptanedicarboxylic acid, 1,7-dimethyl-1,7-heptanedicarboxylic acid, 1,3-dimethyl-1,3,
9-nonanetricarboxylic acid, 1,3-dimethyl-3-carbomethoxy-1,9-nonanedicarboxylic acid, 1,3-dimethyl-
1,7-heptanedicarboxylic acid, 1-methyl-3-ethyl-1,7-heptanedicarboxylic acid, 7-ethyl-1,16-hexadecanedicarboxylic acid, 7,8,11,12-tetramethyl-
1,18-octadecanedicarboxylic acid, 7,8-dimethyl-1,1
4-tetradecanedicarboxylic acid, 1-methyl-1,6-hexanedicarboxylic acid, 1,3-dimethyl-3-carbomethoxy-1,8-octanedicarboxylic acid, 1,3-dimethyl-1,3,
8-octanetricarboxylic acid, 1-methyl-1,8-octanedicarboxylic acid, 1,3-dimethyl-3-carbomethoxy-1,10-decanedicarboxylic acid, 1,3-dimethyl-1,3,10
An acid selected from -decanetricarboxylic acid, 7-phenyl-7-methoxy-1-octanecarboxylic acid, 6-phenyl-6-methoxy-heptanecarboxylic acid, 6-ethyl-1,14-tetradecanedicarboxylic acid, or One or more of the salts are used as main solutes, and one or more of orthophosphoric acid, phosphorous acid, and alkyl phosphate esters are added and dissolved to dissolve them. liquid. 2. The electrolytic solution for driving an electrolytic capacitor according to claim 1, wherein the alkyl phosphates are monobutyl phosphate and tributyl phosphate. 3. The electrolytic solution for driving an electrolytic capacitor according to claim 1, wherein the solvent other than γ-butyrolactone is ethylene glycol. 4. The electrolytic solution for driving an electrolytic capacitor according to claim 1, wherein the salt is an ammonium salt. 5. The electrolytic solution for driving an electrolytic capacitor according to claim 1, wherein the salt is a secondary amine salt. 6. The electrolytic solution for driving an electrolytic capacitor according to claim 1, wherein the salt is a tertiary amine salt. 7. The electrolytic solution for driving an electrolytic capacitor according to claim 1, wherein the salt is a quaternary ammonium salt. 8. The electrolytic solution for driving an electrolytic capacitor according to claim 5, wherein the substituent of the secondary amine salt is one or two selected from a methyl group, an ethyl group, a propyl group and a butyl group. 9. The electrolytic solution for driving an electrolytic capacitor according to claim 6, wherein the substituent of the tertiary amine salt is one or more selected from a methyl group, an ethyl group, a propyl group, and a butyl group. 10. The electrolytic solution for driving an electrolytic capacitor according to claim 7, wherein the substituent of the quaternary ammonium salt is one or more selected from a methyl group, an ethyl group, a propyl group, and a butyl group.