JPH0257331B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a non-polar electrolytic capacitor having a novel structure that can meet market demands for smaller and thinner capacitors. [Technical background of the invention and its problems] In recent years, with the trend toward unitization of electronic components in various electronic devices, the market demand for smaller and thinner electronic components has become stronger. This is not an exception. An example of an electrolytic capacitor that can meet such market demands and whose demand will continue to increase in the future is, for example, a film package type electrolytic capacitor. Conventionally, the general structure of a film package type electrolytic capacitor is, for example, a three-layer laminate of a polyester film, an aluminum foil, and an ionomer sheet, or a four-layer laminate of a polyester film, an aluminum foil, an insulating layer, and an ionomer sheet, as shown in Figure 16. Using any of the laminated materials 21, the surfaces of the ionomer sheets of the laminated materials 21 are faced to each other, and an anode foil, a capacitor paper, and a cathode foil are stacked and rolled between them, and then flattened and electrolyzed for driving. A liquid-impregnated capacitor element 22 is sandwiched, lead terminals 23 and 24 led out from the capacitor element 22 are drawn out, and the periphery of the laminate material 21 is sealed by heat compression bonding or ultrasonic welding. . The aluminum foil is interposed in the laminate 21 to prevent the driving electrolyte from permeating from the polyester film surface, which is the outermost surface of the laminate 21, and to form a recess to accommodate the capacitor element 22. The purpose is to maintain the However, the electrolytic capacitor with the above configuration is
There was a problem with the sealing part of the lead terminals 23 and 24 to the outside. In other words, when thermocompression bonding is used as a sealing method, it is very difficult to control the degree of pressure and temperature, and if the temperature of the pressure is too high, the ionomer sheet may be melted during the process of being placed in a molten state. Terminal 23, 2
4 moves, the aluminum foil comes into contact with the lead terminals 23 and 24, and the space between the lead terminals 23 and 24 is shot, and if the pressurizing temperature is insufficient, the seal is incomplete and the electrolyte leaks. In the case of ultrasonic welding, it is difficult to bond the ionomer sheet and the lead terminals 23, 24, and there is a risk of electrolyte leakage, which in any case has a problem that causes a fatal drawback as an electrolytic capacitor. . Furthermore, even if these problems could be solved by carefully examining the control of pressure and temperature, the capacitor element 22 constituting the electrolytic capacitor having the above structure is wound and flattened, and the product dimensions, especially the thickness. For example, in order to achieve an extremely small capacitance, the anode foil size can theoretically be small, but when making a wound element, there is a limit on the winding machine, and the chemical composition of the electrode foil is limited. It should be possible to make it smaller by increasing the voltage or lowering the etching roughness, but with a CV (capacitance x voltage) value of 35, the product size is 7 x 7 mm and the thickness is 2.5 mm.
This was the limit, and it was impossible to further reduce the size and thickness of the film package type electrolytic capacitor constructed as described above. Furthermore, in order to obtain a non-polar film package type electrolytic capacitor, the volume of the wound element must be approximately doubled, and the product size must eventually become proportionally larger. [Object of the invention] The present invention has been made in view of the above points, and
The object of the present invention is to provide a non-polar electrolytic capacitor having a novel structure that contributes to significant reduction in size and thickness and has stable electrical characteristics. [Summary of the Invention] The electrolytic capacitor of the present invention uses a pair of electrode laminate materials in which a solderable metal foil and an etched and chemically treated valve action metal foil are bonded together, and a bond between the valve action metal foils of the pair of electrode laminate materials is provided. It is characterized in that an organic semiconductor layer is sandwiched between the valve metal foil surfaces and the valve metal foil surfaces are sealed together by heat compression bonding, ultrasonic welding, or the like via a heat-fusible resin. [Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. That is, FIGS. 4 and 5 show an electrode laminate material 1 constituting the present invention, which is etched with two solderable metal foils made of copper, nickel, iron, etc., for example. The valve metal foil 3 is made of, for example, aluminum, tantalum, titanium, niobium, etc., which has been cleaned, chemically treated at a voltage suitable for the product's rated voltage to form an oxide film, and then bonded with a conductive adhesive. ing. FIG. 6 shows a heat-fusible resin sheet 4 made of polyethylene, polypropylene, ionomer (polyethylene methacrylate ester), or a mixture of polyethylene and ionomer, etc., and has a rectangular punched part 5 of the required size on the inside. It is formed by forming. FIG. 7 shows the quinolinium-TCNQ complex salt, dimethylfericinium-TCNQ complex salt, and cobalticinium complex salt constituting the present invention.
TCNQ complex salt, N-normal propyl xinoline-TCNQ complex salt, methylquinoline-TCNQ complex salt,
Ethylquinoline-TCNQ complex salt, TTF-TCNQ
This is an organic semiconductor sheet 6 made into a sheet by heating a complex salt or the like using a mold. Thus, a nonpolar electrolytic capacitor is constructed using the electrode laminate material 1, heat-fusible resin sheet 4, and organic semiconductor sheet 6, and the combined construction thereof will be explained with reference to FIG. That is, first, cut the electrode laminate material 1 into a size that is twice the effective area calculated based on the desired capacitance, plus the amount to be cut after assembly, so that the two sides of the valve metal foil face each other. The valve action metal foil 2 is bent in two, and a heat-fusible resin sheet 4 having a square punching part 5 inside is placed between both sides of the valve metal foil 2, and an organic semiconductor sheet is placed inside the square punching part 5. 6, the bent portions of the electrode laminate material 1 are bent all the way, and the contact surfaces of the opposing valve metal foil 2 and heat-fusible resin sheet 4 are heated by heat compression bonding or ultrasonic welding. The fusible resin sheet 4 is melted to adhere and seal the peripheral parts of the two valve metal foils, and at the same time, the organic semiconductor sheet 6 is sandwiched between the valve metal foils 2 of the electrode laminate material 1, and then bent. The electrode laminate material 1 is separated by cutting out the electrode laminate material 1 to obtain a finished product as shown in FIGS. 1 and 2. According to the non-polar electrolytic capacitor constructed as described above, the electrode itself that determines the capacitance is the valve metal foil 2 of the electrode laminate material 1 that constitutes the exterior.
Therefore, the size of the electrode laminate material 1 is determined by the required capacitance, and the capacitance and the size of the electrode laminate material 1 have a comparative relationship. In electrolytic capacitors, the product size is relatively small, which greatly contributes to miniaturization and thinning, and is extremely effective in achieving maximum component mounting density when used on wiring boards. In addition, the solderable metal foil 3 that makes up the electrode laminate material 1 functions as an external terminal as it is, and can be easily mounted and used as a chip-type electrolytic capacitor. It is possible to easily connect a lead-out terminal of any configuration to any location of the device, making it suitable for arbitrary incorporation into various devices. Furthermore, unlike conventional film package type electrolytic capacitors, there is no need to lead out external terminals from the seal portion, so it has excellent electrical properties such as not only preventing electrical short circuits but also ensuring excellent sealing performance. Next, the actual state of miniaturization and thinning according to the present invention will be described based on specific examples shown below. That is, the first
Design value 50WV constructed using the materials shown in the table.
Tables 2 and 3 show the initial electrical characteristics, product dimensions, and weight of non-polar electrolytic capacitors for the 0.1μF example (A) and the design value 50WV-0.47μF example (B). It became as shown in .

【table】

【table】

【table】

[Table] The sealing method for electrolytic capacitors is 160 to 170℃.
By heat adhesion for 2 to 3 seconds. In addition, W, H, t indicating product dimensions in Table 3 are W, H, t shown in Fig. 1.
shows. Next, the capacitance change rate with respect to time at 85° C., tan δ and leakage current characteristics of Example (A) and Example (B) are shown in FIGS. 8 to 13. Furthermore, the 8th
(C) in Figures to Figure 13 is a non-polar electrolytic capacitor of a conventional reference example of 3 mmφ x 5 mmL with a rubber stopper and an aluminum case with the same design values as those of the above embodiments (A) and (B). shows the curve according to As is clear from Table 2, the non-polar electrolytic capacitor according to the present invention can be made smaller and thinner in proportion to the desired capacitance, and can also be made lighter in weight. This contributes to maximum miniaturization and thinness, for example, it is possible to easily obtain extremely small capacitors of 7 mm x 7 mm or less, which was impossible with film package type electrolytic capacitors, and it also reduces capacitance, tan δ, and leakage current. Its initial properties are also very good. Furthermore, as is clear from Figs. 8 to 13, these characteristics have little change over time, and compared to the conventional reference example (C), it is more reliable and extremely effective in practice. . In the above embodiment, the case where unit capacitors are made individually has been explained, but as shown in FIG. The valve metal foil 11 is folded in two as shown in FIG.
A heat-fusible resin sheet 13 having a plurality of rectangular punched parts 12 is arranged between both surfaces, an organic semiconductor sheet 14 is arranged in each of the punched parts 12, and a bent part of the electrode laminate material 10 is formed. After the valve action metal foil 11 and the heat-fusible resin sheet 13 are bent all the way, the contact surfaces of the valve action metal foil 11 and the heat-fusible resin sheet 13 are bonded and sealed by heat pressure bonding or ultrasonic welding, and then the bent portion is included. By cutting off the seal, a large amount of product can be obtained at one time, which greatly contributes to improving work efficiency. In the figure, 15 is a metal foil that can be soldered. Furthermore, in the above embodiments, a sheet-like organic semiconductor layer was used as an example, but a structure in which the above-mentioned material is made into a paste form and printed on, for example, an electrode laminate material, or a large electrode laminate material as shown in FIG. The heat-fusible resin sheet 17 is placed on the heat-fusible resin sheet 16, and the punched portion 1 is provided on the heat-fusible resin sheet 17.
The same effect can also be obtained by placing the powdered organic semiconductor powder 19 on the electrode laminate material 16, bending the bent portions of the electrode laminate material 16 as much as possible, and sealing the organic semiconductor layer. Furthermore, although the above embodiments have been described with reference to square shapes, it goes without saying that other shapes can be applied depending on the purpose. [Effects of the Invention] According to the present invention, a novel product which has good electrical characteristics, can be downsized proportionally according to the capacitance value, and can obtain maximum component mounting density when used in a wiring board. A non-polar electrolytic capacitor with this structure can be obtained.

[Brief explanation of the drawing]

Figures 1 to 7 relate to one embodiment of the present invention, and Figures 1 and 2 show non-polar electrolytic capacitors, with Figure 1 being a perspective view and Figure 2 being the same as Figure 1. X
A sectional view, FIG. 3 is a perspective view explaining the structure during assembly, FIGS. 4 and 5 show the electrode laminate material, FIG. 4 is a perspective view, and FIG. 5 is an enlarged front view of part A in FIG. FIG. 6 is a perspective view showing a heat-fusible resin sheet;
Fig. 7 is a perspective view of the separator, Fig. 8 is a time-capacitance change rate characteristic curve, Fig. 9 is a time-tanδ characteristic curve, Fig. 10 is a time-leakage current characteristic curve, and Fig. 11 is a time-leakage current characteristic curve. Fig. 12 is a time-tanδ characteristic curve diagram, Fig. 13 is a time-leakage current characteristic curve diagram, and Fig. 14 is an explanation of the configuration during assembly according to another embodiment of the present invention. Perspective view, No. 15
16 is a perspective view illustrating the structure of an electrolytic capacitor in the middle of assembly according to another embodiment of the present invention, and FIG. 16 is a perspective view illustrating the structure of an electrolytic capacitor according to a conventional reference example. 1, 10, 16... Electrode laminate material, 2, 1
1... Valve metal foil, 3, 15... Solderable metal foil, 4, 13, 17... Heat-fusible resin sheet, 6, 14... Organic semiconductor sheet, 19...
Organic semiconductor powder.

Claims (1)

[Scope of Claims] 1. A pair of electrode laminate materials consisting of a solderable metal foil and an etched and chemically treated valve metal foil, and an organic semiconductor sandwiched between the valve metal foil surfaces of the pair of electrode laminate materials. What is claimed is: 1. An electrolytic capacitor comprising: a layer; and a heat-fusible resin disposed around the organic semiconductor layer and bonding between surfaces of the valve metal foil. 2. The electrolytic capacitor according to claim 1, wherein the solderable metal foil is made of copper, nickel, iron, or the like. 3 The organic semiconductor layer is quinolinium-TCNQ complex salt,
Dimethyl felicinium-TCNQ complex salt, cobalticinium-TCNQ complex salt, N-normal propyl xinoline-TCNQ complex salt, methylquinoline-TCNQ complex salt, ethylquinoline-TCNQ complex salt,
The electrolytic capacitor according to claim 1 or 2, characterized in that it is made of a TTF-TCNQ complex salt. 4. The electrolytic capacitor according to claims 1 to 3, wherein the heat-fusible resin is made of polyethylene, polypropylene, an ionomer, a mixture of polyethylene and an ionomer, or the like.