JPH0620032B2 - Electrolytic capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an electrolytic capacitor having a novel configuration.

(Prior Art) Generally, a dry foil type electrolytic capacitor is formed by connecting a pair of lead terminals also made of aluminum to a pair of positive and negative electrode foils made of aluminum foil and winding a spacer between the pair of positive and negative electrode foils. It is rotated and then impregnated with the driving electrolytic solution, housed in a case, and the case opening is sealed. Generally, the purpose of interposing a spacer is to isolate and insulate a pair of positive and negative electrode foils from each other and to retain a driving electrolytic solution, which is an important constituent factor in a dry foil type electrolytic capacitor. Therefore, the commonly used spacer is kraft paper, or the kraft paper has a density of 0.3 to
The density is comparatively high at 0.8 g / cm ^3, and the apparent cross-sectional shape of the fibers that make up the kraft paper has a large apparent specific resistance, which impairs tan δ characteristics. Also, kraft paper is a problem in papermaking technology. The thickness is 30 μm or more, and it cannot be made thinner than that, which is a factor that hinders miniaturization. Further, there is a drawback that ignition may occur at the time of capacitor destruction due to application of overvoltage or reverse voltage, and continuous combustion may occur. For this reason, there is a tendency to use low-density manila paper instead of kraft paper, which greatly contributes to the improvement of tan δ characteristics, but the cost of manila paper is several times higher than kraft paper,
In addition, in order to withstand the strength after papermaking in the manufacturing process (especially the winding process) of the capacitor, the thickness of 40 μm or more must be used, which is still an obstacle to miniaturization.

In addition, since the liquid driving electrolyte is used, there is a limit to the improvement of tan δ characteristics. Further, the liquid driving electrolyte has a tendency to increase the specific resistance at low temperatures, and the low temperature characteristics are extremely deteriorated to be used in a wide temperature range. In addition to having problems to be solved in practice, such as lack of reliability, the element shape is a wound type,
Moreover, since the lead-out terminal is inserted midway, it has a problem of poor frequency characteristics.

Therefore, in recent years, for example, JP-A-58-17609, JP-A-58-191414 or JP-A-59-63.
As disclosed in Japanese Patent Publication No. 604, instead of the driving electrolyte, N-n-propyl (or N-iso-propyl) isoquinoline, N-ethylisoquinoline, N-n-butylisoquinoline, and N-position are hydrocarbon groups. Quinoline substituted with,
It has been proposed that a TCNQ complex composed of isoquinoline or pyridine is used as a solid electrolyte to improve the characteristics. In an electrolytic capacitor using such TCNQ complex, generally, these TCNQ complexes are melt-impregnated and used, but since the TCNQ complex is heated for a long time when melt-impregnated, the conductivity of the TCNQ complex easily decreases. There is a problem with tan δ characteristics, and the element shape is a type in which a lead terminal is inserted in the middle of the winding as in the past, so the characteristics at high frequencies are poor, and since a spacer is used, the positive and negative electrodes (about 40 ˜50 μ) is wide and resistance is still large.

However, the present inventor applied for a patent application No. 60-78649 for the purpose of eliminating the above-mentioned various defects. That is, according to the prior art, as shown in FIG. 4, an anodic oxide film 24 is formed on the surface of a valve action metal film 23 having one end as a blank part 22 on one surface of an insulator 21, and then the anodic oxide film 24 is formed. The TCNQ complex film 25 is formed on the surface of the blank portion 22 from the surface excluding the end surface located on the opposite side of the blank portion 22, and the end surface of the TCNQ complex film 25 located on the opposite side of the blank portion 22. As shown in FIG. 3, a required number of composite film layers 27 each having an anode electrode film 26 formed on the surface except for the above are laminated, and electrode lead-out portions 28 are formed on both end surfaces. It is a great contribution. 29 is an external terminal. However, the electrode lead-out portion 28, which is one of the anodes in the electrolytic capacitor having the above-described structure, has an area of 10 μm thick at the end portion of the valve action metal film 23, and the aluminum as the valve action metal film 23 and the electrode lead-out portion 28. As a result, the contact is largely provided due to the electrical connection by the contact with the silver adhesive as described above, and in an extreme case, contact failure occurs, and eventually the tan δ characteristic as the capacitor is impaired.

(Problems to be Solved by the Invention) By using the TCNQ complex as described above and making the element shape into a non-inductive type, it is possible to improve the characteristics as compared with the prior art. There was a problem.

The present invention has been made in view of the above points, and an object thereof is to provide an electrolytic capacitor having a novel structure by improving the contact structure between the valve action metal and the electrode lead-out portion serving as an anode, and stabilizing various characteristics. It is what

[Structure of the Invention] (Means for Solving the Problems) In the electrolytic capacitor of the present invention, a valve action metal film is formed on one surface or both surfaces of an insulator with one end surface being a blank portion, and the blank portion of the metal film is formed. An anodic oxide film is formed on the surface other than the one end face located on the opposite side to the TCNQ complex film on the oxide film, and the cathode electrode film is formed on the complex film and the blank face. An anode electrode film is formed on the surface of the metal film without contacting the oxide film, and a plurality of multiple film layers in which a resin film is formed on the surface including the anode electrode film and the cathode electrode film are laminated,
The electrode lead-out portions are formed on both end surfaces.

(Function) According to the electrolytic capacitor configured as described above, the valve action metal film serving as the anode and the electrode lead-out portion have a structure in which the anode electrode film provided on the valve action metal film is interposed, and thus the contact area between the two Can be secured to a large value, the electric resistance can be reduced, and tan δ characteristics with excellent variation can be obtained.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings.

That is, as shown in FIG. 2, for example, a plastic film sheet or a ceramic sheet made of polyester, triacetate, tetrafluoroethylene, polycarbonate, polyamide, polyimide or the like is provided on one surface of an insulator 1 with one end as a blank portion 2 made of aluminum metal. Is deposited or laminated to form a valve action metal film 3, and then the surface of the valve action metal film 3 excluding one end face opposite to the blank portion 2 is anodized to form an anodized film 4. Then, on the surface of the anodic oxide film 4, for example, 2,
2'-bipyridinium (TCNQ) ₂ , 4-hydroxy-N-benzylanillium (TCNQ) ₂ , 4-amino-2,3,5,6-tetramethylanilinium (T
CNQ) ₂ , pyridinium (TCNQ) ₂ , 4-cyano-N-methyl-pyridinium (TCNQ) ₂ , N-ethylquinolinium (TCNQ) ₂ , N- (2-phenethyl).
A TCNQ complex made of quinolinium (TCNQ) ₂ or the like is vacuum-deposited to form a TCNQ complex film 5. Then the T
A valve action in which a metal such as silver or copper is formed on the CNQ complex film 5 surface and the blank 2 surface by a means such as screen printing, vapor deposition or sputtering, and the anodic oxide film 4 is not formed. An anode electrode film 7 is formed on the surface of the metal film 3 by the same means as the means for forming the cathode electrode film 6 without contacting the anodized film 4, and on the surface including the anode electrode film 7 and the cathode film 6, for example, An epoxy resin is screen-printed to obtain a multiple film layer 9 having a resin film 8 formed thereon. Then, as shown in FIG. 1, a required number of the multi-layered baths 9 are laminated, and metal such as aluminum or solder is applied to both end faces by metallikon or coating to form an electrode lead-out portion 10. The terminal 11 is attached and housed in a case or covered with a resin or the like to form an exterior (not shown).

The electrolytic capacitor configured as described above has a structure in which the anode electrode film 7 formed on the surface of the valve action metal film 3 serving as an anode serves as a connecting portion with the electrode lead-out portion 10, and the contact between the both at the connecting portion. Since the area is large and can be ensured reliably, the electrical resistance of the connection portion is small and the factor that hinders the tan δ characteristic is eliminated,
In addition to being able to obtain excellent tan δ characteristics with no variations, the element characteristics are spacerless, no driving electrolyte solution is used, and since it is a non-dielectric type, temperature characteristics,
The high-frequency characteristics also have an excellent effect that is significantly improved as compared with the conventional example.

Next, an example of comparison between the embodiment of the present invention and the reference example will be described.

Example Using a laminated aluminum film having a thickness of 10 μm laminated on one surface of a polyester film, 2,2′-bipyridinium (TCNQ) ₂ was vacuum-deposited as a TCNQ complex. Both the cathode electrode film and the anode electrode film were screen-printed with Ag paste and screen-printed with epoxy resin. A plurality of multi-layered films having the structure shown in FIG. 2 were laminated, and metallikon electrodes were provided on both end faces, and epoxy resin was used as the exterior structure. Rating of 25 WV
1 μF electrolytic capacitor (A). Reference Example Using an aluminum laminate film obtained by laminating aluminum having a thickness of 10 μm on one surface of a polyester film, 2,2′-bipyridinium (TCNQ) ₂ was vacuum-deposited as a TCNQ complex. Ag as cathode electrode film
Screen-printing the paste, screen-printing the epoxy resin, screen-printing the epoxy resin, and laminating a plurality of multi-layers having the structure shown in FIG. 4, applying metallikon electrodes on both end faces, and coating the epoxy resin as the exterior structure. 25WV 1μF electrolytic capacitor (B).

However, as a result of examining various characteristics in the example (A) according to the present invention and the conventional reference example (B), the results are shown in the following table. There are 20 samples (A) and (B).

As is clear from the above table, the example (A) is the reference example (B).
Compared with the above, the variation of the contact resistance between the anode and the metallikon electrode is extremely small, and the variation of tan δ is also small.
Therefore, the tan δ characteristic is excellent, demonstrating the excellent effect of the present invention.

Although the valve metal film provided on one surface of the insulator has been described as an example in the above embodiments, it is needless to say that the invention can be applied to both surfaces, and in the above embodiment, aluminum metal is used as the anode electrode film. However, the same effect can be obtained by using a valve-action metal such as tantalum, titanium, or niobium.

[Effects of the Invention] As described above, according to the configuration of the present invention, by providing the anode electrode film on the valve action metal film surface as the anode extraction structure, the tan δ characteristic is improved and TCNQ without a spacer is provided.
It is possible to obtain an electrolytic capacitor of high practical value as a non-induction type using a complex.

[Brief description of drawings]

1 and 2 relate to an embodiment of the present invention. FIG. 1 is a front sectional view showing an electrolytic capacitor, FIG. 2 is a perspective view showing a multilayer film constituting FIG. 1, FIG. FIG. 4 relates to a reference example, FIG. 3 is a front sectional view showing an electrolytic capacitor, and FIG. 4 is a perspective view showing a multi-layer film constituting FIG. 1 ... Insulator, 2 ... Blank space 3 ... Valve action metal film, 4 ... Anodic oxide film 5 ... TCNQ complex film, 6 ... Cathode electrode film 7 ... Anode electrode film, 8 ... Resin film 9 ... Composite film layer, 10 ... Electrode extraction part

Claims (1)

[Claims] 1. A valve action metal film having one end surface formed as a blank portion on one surface or both surfaces of an insulator, and anodization formed on a surface of the metal film excluding the one end surface opposite to the blank portion. A film, a TCNQ complex film formed on the oxide film, a cathode electrode film formed on the complex film and the blank surface, and formed on the valve action metal film surface without contacting the oxide film An anode electrode film, a composite film layer comprising a resin film formed on the surface including the anode electrode film and the cathode electrode film, and electrode lead-out portions formed by stacking a plurality of the composite film layers on both end faces. An electrolytic capacitor characterized in that