JPH0334520A - Manufacture of film capacitor - Google Patents

Abstract

PURPOSE:To obtain a sufficient bonding strength between an electrode and a contact layer even when the time to come into contact with a gas is shortened by a method wherein an external electrode extraction face of a capacitor raw-body which has wound or laminated two or more kinds of organic materials via the electrode is brought into contact with a gas containing a component reactive to the organic materials and is removed selectively and, after that, an end-face electrode is formed. CONSTITUTION:A capacitor element is obtained by cutting a film-capacitor raw-body which has wound or laminated alternately, via an electrode 4, polyethylene terephthalate films 1 and polyphenylene oxide coating films 2 as two or more kinds of organic materials of different molecular structures. A gas which has ionized oxygen by a high-frequency electric field and whose reactivity is high is reacted with an electrode extraction end-face of this element to remove the films and the coating films at the electrode extraction end-face part. Since there is a difference between a removal amount of the films and a removal amount of the coating films, the electrode extraction end-face part becomes a recessed and protruding shape. After that, zinc is sprayed on the electrode extraction end-face by a metal spraying method to form the end-face electrode 4; a capacitor element is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing film capacitors widely used in electronic and electrical equipment.

BACKGROUND OF THE INVENTION In recent years, as electronic and electrical equipment has become lighter, thinner, smaller, and more sophisticated, efforts have been made to make film capacitors used in these devices lighter, thinner, smaller, and more efficient.

An example of a conventional method for manufacturing a multilayer film capacitor will be described below with reference to the drawings.

FIG. 5 shows the structure of a conventional multilayer film capacitor element.

In the figure, 51 is a metalized film on one side, 51a is a metal film serving as an electrode, 52 is a gap between the films, and 53 is a margin portion that is a non-metalized portion.

Conventionally, in order to form a film gap 52 on the end face where the end face electrode of a capacitor element is to be formed, a single-sided metallized film 51 is wound up with alternating shifts in the film width direction. As a result, when forming a metallicon as an end electrode, the contact layer is sufficiently penetrated, and a good electrical connection is achieved between the contact layer and the electrode 51a of the single-sided metallized film 51, and sufficient adhesion of the end electrode is achieved. Provides strength.

However, in the above method, a wide single-sided metallized film having a plurality of capacitor elements is cut and divided into unit capacitors, and then the single-sided metalized film is wound, resulting in a problem of low productivity.

Therefore, in recent years, the base material of a film capacitor obtained by winding a wide single-sided metallized film having multiple capacitor elements is cut and slit to form a film capacitor element with uniform end faces, and the end face of the electrode lead-out is A method has been developed in which a film gap is formed by selectively chemically removing the electrode lead end side portion of an organic film by bringing it into contact with a gas containing at least a component that is reactive with the material.

Problems to be Solved by the Invention However, in the method described above, in order to obtain sufficient adhesion strength between the electrode 51a of the single-sided metallized film 51 and the contact layer, at least a component reactive with the organic material must be added. This has the disadvantage that the contact time with the gas contained therein must be extended.

The present invention solves the above-mentioned conventional problems, and is capable of obtaining sufficient adhesion strength between the electrode 51a and the contact layer even if the time period during which the electrode lead-out end face is brought into contact with a gas containing a reactive component is shortened. The purpose of the present invention is to provide a method for manufacturing a film capacitor that enables the following.

Means for Solving the Problems In order to achieve this object, the method for manufacturing a film capacitor of the present invention uses a film capacitor element body in which at least two or more types of organic materials having different molecular structures are alternately wound or laminated with electrodes interposed therebetween. The end surface electrode is formed after the external electrode extraction surface of the organic material is brought into contact with a gas containing at least a component reactive with the organic material to chemically and selectively remove the component.

Effect: With this method, organic materials with different molecular structures have different reactivity when brought into contact with a gas containing a reactive component, resulting in a difference in the amount removed. For this reason, a step is formed on the external electrode extraction surface of the film capacitor body. Thereafter, a contact layer is formed using metallicon on the external drawing surface of the capacitor body, so that sufficient adhesion strength can be obtained between the electrode of the single-sided metallized film and the contact layer due to the step difference.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of a film capacitor in an embodiment of the present invention.

In the figure, 1 is a polyethylene terephthalate film, 2 is a polyphenylene oxide coating film, 3 is an aluminum vapor deposited film that becomes an electrode, and 4 is an end face electrode formed by metal spraying.

In this example, first, a polyphenylene oxide coating film 2 is formed on both sides of a metallized film in which IFF grooves are provided in the length direction of the film on both sides of a polyethylene terephthalate film 1, and a metallized film having a plurality of capacitor elements is formed. Obtained. This metallized film was wound onto a flat bobbin, pressed while heating, separated from the bobbin, and cut to obtain a laminate as shown in FIG. 2. This laminate was cut at the electrode lead-out end face position of each capacitor element to obtain the capacitor element shown in FIG.

A highly reactive gas obtained by ionizing oxygen by a high-frequency electric field was reacted with the electrode lead-out end face of the capacitor element thus obtained to remove the film and coating on the electrode lead-out end face side. At this time, since there was a difference between the amount of film removed and the amount of coated film removed, the electrode lead-out end surface became uneven as shown in FIG. Thereafter, zinc was sprayed onto the end face of the electrode lead-out using a metal spraying method to form an end face electrode 4 to obtain a capacitor element.

As a comparative example, a single-sided metalized polyethylene terephthalate film was laminated, and a capacitor element as shown in FIG. 5 was obtained using the same conditions and construction method as in this example.

The adhesion between the end face electrodes of the capacitor of the present invention obtained as described above and the capacitor of the comparative example was subjected to a tensile test, and the adhesion was evaluated based on the breaking strength. The results are shown in Figure 4.

As shown in FIG. 4, the film capacitor of the present invention is
It can be seen that the adhesion force of the end face electrode is very strong and its variation is small.

Effects of the Invention As described above, the present invention provides a film capacitor body in which organic materials with different molecular structures are alternately wound or laminated via electrodes, and the external electrode lead surface of the film capacitor body is brought into contact with a gas containing a reactive component. By forming a chemically removed rear end face electrode, the adhesion strength between the end face electrode layer and the electrode of the metallized film can be made stronger.

[Brief explanation of drawings]

Figure 1 is a diagram showing the structure of a film capacitor obtained by the manufacturing method of the present invention, Figures 2 and 3 are diagrams for explaining this example, and Figure 4 is a diagram showing the structure of a film capacitor obtained by the manufacturing method of the present invention. FIG. 5, which is a diagram showing a comparison of characteristics, is a diagram showing the structure of a conventional product.

Claims (3)

[Claims] (1) The external electrode extraction surface of a film capacitor body, which is made by alternately winding or laminating at least two types of organic materials with different molecular structures through electrodes, is heated to a gas containing a component reactive with the organic materials. 1. A method for manufacturing a film capacitor, which comprises forming an end electrode after contacting and chemically selectively removing the capacitor. (2) Polyethylene terephthalate as an organic material,
2. The method for manufacturing a film capacitor according to claim 1, wherein at least two or more of polypropylene, polyethylene naphthalate polyphenylene sulfide, polyether ether ketone, polyphenylene oxide, and polycarbonate are used. (3) The method for manufacturing a film capacitor according to claim 1, wherein the reactive gas is oxygen radicals extracted from oxygen-containing plasma.