JP2731257B2 - Manufacturing method of film capacitor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a film capacitor such as a polypropylene film capacitor used for electronic equipment and electric equipment.

[Conventional technology]

In recent years, electronic devices used in electronic devices and electrical devices
There is a demand for miniaturization, high performance, and low cost. In order to meet these demands, film capacitors are also being developed for chip formation, high reliability, and low cost.

6 and 7 show an example of a conventional method for manufacturing a film capacitor. Fused adhesive layer on both sides of organic film 21
A protective film 23 formed only by 22 is wound and laminated on a flat bobbin 24 to form a protective winding portion B, and then a double-sided metallization having a molten adhesive layer 22 on the surface of an electrode metal 25 deposited on the front and back of the organic film 21 is formed. The film 26 is wound and laminated following the protective winding portion B to form the capacitance portion C, and the above-described protective film 23 is rolled and laminated to form the protective winding portion B ', thereby obtaining the laminate 27.
FIG. 7 is an enlarged cross-sectional view of the film capacitor element plate 28 obtained by cutting the laminated body 27 wound and laminated on the flat bobbin 24 by the above-described method on one surface of the flat bobbin 24 at right angles to the winding direction. The protection portion B, the capacitance portion C, and the protection portion B 'are sequentially wound and laminated from one side of the flat bobbin 24. The one cut and divided at the position of the dashed line D in the figure becomes the film capacitor body 31, and the cut and divided surface becomes the electrode lead portion. The portions on both sides cut and divided are non-capacitance portions 29 that do not contribute to the capacity of the film capacitor to be a product.
The end of the laminated electrode metal 25 is exposed, and a gap 30 is formed in the molten adhesive layer 22 on the organic film 21 to extract the electrode. The width of the gap 30 is at least the minimum in terms of manufacturing technology.
The width is 1 mm, and the width occupied by the non-capacitance portion 29 in each film capacitor body 31 is necessarily 2 mm or more. Also, even if the division width of the film capacitor element plate 28 is reduced to reduce the size of the product, the width of the non-capacitance portion 29 occupying the film capacitor body 31 is not reduced, which is an obstacle to miniaturization of the product. . In addition, in order to form the non-capacitance portion 29 with a small width, it is essential to increase the precision of the manufacturing equipment, and the technical difficulty is high. There is a problem that the cost increases.

Therefore, the electrode lead-out part of the film capacitor body 31
There has been proposed a method of forming electrodes after chemically removing 32 organic materials. 8 to 11 show an example of a method of manufacturing the proposed film capacitor.
Electrode metal is vapor-deposited on one side of the organic film, and a single-sided metallized film 26 'having a molten adhesive layer
(FIG. 8 (a)). Next, the obtained laminated body 27 'of the single-sided metallized film 26' is heat-pressed with a hot plate, and the interlayers of the single-sided metallized film 26 'are adhered to each other by a molten adhesive layer (FIG. 8 (b)). Single-sided metallized film
The laminate 27 'of 26' is bobbin separated from the flat bobbin 24 by a cutter or the like, and the two film capacitor element plates 28 '
Is obtained (FIG. 8 (c)). Further, the obtained film capacitor element plate 28 'is slit into predetermined lengths by a knife or the like in the longitudinal direction at the time of winding to obtain a film capacitor element body 31' (FIG. 8 (d)).

Film capacitor element plate 28 'obtained by the above method
9 is an enlarged sectional view of FIG. 21 is an organic film, 25 is an electrode metal deposited on the organic film 21, 33 is an organic film
A streak-like margin extending in the length direction of 21, 22 is a fusion bonding layer, and 29 ′ is a non-capacity part. The single-sided metallized film 26 'of the lower three layers and the upper two layers of the rolled and laminated film capacitor element plate 28' has a margin 33 formed at the same position in the thickness direction, so that the capacity of the film capacitor becomes a product. Is a layer of a portion that does not contribute and becomes a reinforcing layer of the film capacitor body 31 '. The dashed-dotted line E in the figure is a slit position for dividing the film capacitor body 31 '. FIG. 9 (b)
Is an enlarged sectional view of the film capacitor body 31 'divided by this. The arrow face in the figure is the electrode lead-out portion 32 of the film capacitor body 31 '.

Next, the electrode lead-out part of the film capacitor body 31 '
FIGS. 10 (a) and 10 (b) show a method of chemically removing a dielectric film 34 composed of a 32 organic film 21 and a molten adhesive layer 22.
Shown in The film capacitor body 31 'masked by the mask 35 is disposed in a vacuum vessel 36 which can be maintained under reduced pressure and is grounded, and the vacuum vessel 36 has an electrode 37 for applying high frequency, a high frequency power supply 38, and a quartz window 39. , Gas introduction device
40, a vacuum exhaust device 41 is provided. This device chemically removes the dielectric film 34 of the electrode lead portion 32 of the film capacitor body 31 'by oxygen radicals extracted by plasma generated by applying high frequency to a gas reacting with the organic material. Processing is performed to expose the electrode metal 25 to the end face. The removal amount of the dielectric film 34 is about 50 to 100 μm
(Dimension F in the figure), the variation of the removal amount is about 20 ~ 30μm
(Dimension G in the figure), and the non-capacity part of the electrode lead-out part 32
It can be manufactured in a size sufficiently smaller than the 29 'size of 300 μm. Further, a defect such as a pinhole generated in the margin 33 or the dielectric film 34 is shielded by the mask 35 so as not to come into contact with the reactive gas during the chemical selective removal processing of the dielectric film 34.

Next, FIG. 11 shows steps from the above-described chemical selective removal processing to completion of the film capacitor element 43. A metal material is sprayed on the end face of the electrode lead portion 32 from which the dielectric film 34 has been selectively removed by the metallicon process to form an electrical connection with the vapor-deposited metal 25 exposed on the end face, thereby forming a film capacitor element. Body 31 'and external electrode 42 with sufficient adhesion
Is formed (FIG. 11 (a)). Next, if necessary, the external electrode 42 is cut and shaped in an electrode surface cutting step (FIG. 11 (b)).
In the cutting step, the film capacitor body 31 'is cut into a predetermined size to obtain the film capacitor element 43.

[Problems to be solved by the invention]

However, in the above manufacturing method, the dielectric film 34
In the step of chemically selective removal of the film capacitor element, the film capacitor element 31 'is exposed to plasma energy, or receives the reaction heat when the constituent molecules of the dielectric film 34 are ashed by oxygen radicals. There has been a problem that the temperature of the body 31 'is increased, and the organic film 21 and the molten adhesive layer 22 forming the dielectric film 34 are deteriorated by heat, and the characteristics of a film capacitor as a product are deteriorated.

An object of the present invention is to provide a method of manufacturing a film capacitor in which an organic film having low heat resistance is not thermally deteriorated in a step of selectively removing a dielectric film.

[Means for solving the problem]

The method for manufacturing a film capacitor according to the present invention is characterized in that the film capacitor element having a plurality of electrode metals and a dielectric film made of an organic material disposed between the electrode metals is cooled by heat conduction, The method is characterized in that a dielectric film of an electrode lead-out portion serving as an end face of a body is brought into contact with a gas reacting with an organic material, and an end of the dielectric film is chemically selectively removed.

According to a second aspect of the present invention, there is provided a method of manufacturing a film capacitor according to the first aspect, further comprising: masking the entire surface of the film capacitor body other than the electrode lead portions; A step of laminating one or more of the capacitor bodies with the electrode lead-out portions in the same direction and pressing and holding using a jig, and cooling the film capacitor body by heat conduction through the jig. A step of bringing the dielectric film of the electrode lead-out portion into contact with a gas reacting with an organic material to chemically remove it selectively.

According to a third aspect of the invention, there is provided a method of manufacturing a film capacitor according to the first or second aspect, wherein the film capacitor body is first heated to a certain temperature by heat conduction to obtain a predetermined temperature. After reaching the temperature, the electrode lead portion of the dielectric film is chemically removed selectively while cooling.

[Action]

According to the configuration of the present invention, when the end face of the electrode lead portion of the dielectric film is chemically selectively removed, the heat received by the film capacitor body can be cooled by heat conduction.

According to the structure of claim (2), a defect caused by a margin of the film capacitor body or a pinhole of the organic film is shielded from contact with the reactive gas, and heat received by the film capacitor body is passed through the jig. The end face of the electrode lead portion of the dielectric can be chemically selectively removed while being removed by heat conduction.

According to the configuration of claim (3), first, the film capacitor body is heated to a predetermined temperature by heat conduction at a high temperature rising rate, and then the end face of the electrode lead portion of the dielectric is chemically selected while cooling. It can be removed.

〔Example〕

A first embodiment of the present invention will be described with reference to FIGS. Winding, laminating and slitting are performed in the same manner as in the proposed method for manufacturing a film capacitor, and FIG.
After obtaining the film capacitor body 1 shown in FIG. 1, the dielectric film 5 composed of the organic film of the electrode lead-out portion 2 and the fusion bonding layer on the two surfaces of the film capacitor body 1 indicated by arrows.
The film capacitor body 1 is pressed and held on a jig 4 in order to chemically selectively remove the organic material. FIG. 1 (c) shows a jig holding the film capacitor body 1 under pressure.
FIG. 14 is an enlarged view of an AA ′ part of a side view of FIG. 14 (FIG. 1B). With the electrode lead portions 2 of the film capacitor body 1 in the same direction, three layers are laminated between the respective film capacitor bodies 1 via a mask 17 to form a laminate 6.
The five layers of the laminated body 6 are stacked with two parallel flat plates 18 interposed between the laminated bodies 6, and are held under pressure by a jig 14. The jig 14, the flat plate 18, and the mask 17 are made of stainless steel in this embodiment. However, they are made of metal or inorganic material, and are stable to the reaction of chemical selective removal and have heat conduction. Any material can be used if it is good. In FIG. 2, reference numeral 11 denotes a vacuum vessel grounded to ground, in which electrodes 12 for applying a high frequency and a high frequency power supply 13 are arranged at two upper and lower locations inside. The jig 14 is fixed by a holder 15, and a coolant channel 16 is provided inside the holder 15.
During the step of chemical selective removal of water, the jig 14 and the holder 15 are cooled by heat conduction by circulating the refrigerant through the refrigerant flow path 16 so that the heat received by the film capacitor The heat is exhausted by an external heat exchanger (not shown). Also, the flat plate 18 and the mask 17 can be used alternately.
Alternatively, a jig 14 'shown in FIG. 3 may be used in which the refrigerant is circulated directly to increase the cooling capacity.

As described above, the film capacitor body 1 in which the dielectric film 5 of the electrode lead-out portion 2 of the film capacitor body 1 has been chemically selectively removed is subjected to a metallikon process and an electrode surface cutting process as in the proposed example shown in FIG. Steps and cutting steps are performed to obtain a film capacitor element.

Next, a second embodiment of the present invention will be described. First
In the embodiment of the present invention, the refrigerant supplied to the refrigerant passage 16 is refined oil, and the temperature of the refined oil can be variably controlled from 8 ° C. to 150 ° C., so that the temperature of the refined oil can be controlled from 20 ° C. The refined oil of 150 ° C. is flowed through the coolant channel 16 for a minute, the jig 14 is heated, and the film capacitor element 1 is thermally conductive.
Then, the temperature of the refined oil was lowered to 8 ° C. over about 10 minutes to cool the jig 14, and the dielectric film 5 of the electrode lead portion 2 was selectively removed chemically.

In this embodiment, the refined oil is used as the medium for setting the temperature. However, another medium having good fluidity may be used, and the temperature control from heating to cooling may be performed by switching the medium between the low temperature and the high temperature. .

FIG. 4 is a graph showing the relationship between the temperature of the jig 14 incorporating the film capacitor body 1 of the first embodiment in which only the cooling is performed during the chemical selective removal process and the removal amount of the dielectric film 5. It is. The temperature of the jig 14 relatively indicates the temperature of the film capacitor body 1. As is apparent from this figure, when the temperature of the jig 14 exceeds about 150 ° C., the removal amount of the dielectric film 5 sharply increases.

FIG. 5 shows the temperature change with the processing time of the jig 14 incorporating the film capacitor element body 1 of the first embodiment in which only the jig 14 was cooled during the chemical selective removal processing, First, remove the film capacitor body during the removal process
Supply refined oil at 150 ° C to the refrigerant channel 16 for 20 minutes and heat it.
The temperature change over time of the jig 14 incorporating the film capacitor body 1 of the second embodiment, in which the temperature of the refined oil was cooled down to 8 ° C. over about 10 minutes, is plotted with a black circle. As in FIG. 4, the temperature of the jig 14 indicates the temperature of the film capacitor body 1 relatively. As is clear from this figure, when the jig 14 of the first embodiment is only cooled, the jig temperature reaches about 180 ° C. in about 60 minutes. When the jig 14 is heated, the jig temperature reaches 180 ° C. in about 45 minutes. The removal amount of the dielectric film 5 after elapse of 60 minutes in the first embodiment is substantially equal to the removal amount of the dielectric film 5 after elapse of 45 minutes in the second embodiment. In the embodiment, the removal processing of the dielectric film 5 can be performed in a shorter time, and the productivity can be improved.

In this way, first, the jig 14 is supplied with the refined oil of 150 ° C. to the refrigerant flow path 16 and heated by heat conduction, and then the temperature of the refined oil flowing through the refrigerant flow path 16 is reduced to 8 ° C. and cooled by the heat conduction. While performing the chemical selective removal processing while shortening the removal processing time and improving the productivity,
It is possible to prevent the dielectric film 5 from being deteriorated due to excessive heat.

〔The invention's effect〕

The method for manufacturing a film capacitor according to the present invention is characterized in that the dielectric film of the electrode lead-out portion is chemically and selectively removed while cooling the film capacitor body by heat conduction, so that the dielectric film is not thermally degraded and has a high performance. A film capacitor can be obtained.

According to a second aspect of the present invention, there is provided a method of manufacturing a film capacitor, wherein a defect caused by a margin or a pinhole is shielded from contact with a reactive gas, and a dielectric film of an electrode lead portion is cooled while cooling the film capacitor body by heat conduction. No chemical degradation by heat treatment of the dielectric film,
It is possible to obtain a high-performance and highly reliable film capacitor in which the electrode metal of the defective portion is not exposed.

According to a third aspect of the present invention, there is provided a method for manufacturing a film capacitor, wherein a film capacitor body is first heated to a predetermined temperature by heat conduction, and after the temperature reaches the temperature, the dielectric film of the electrode lead portion is chemically cooled while cooling by heat conduction. By performing the selective removal process, a high-performance and highly reliable film capacitor without thermal degradation of the dielectric film can be manufactured with a shortened chemical selective removal process time and improved productivity.

[Brief description of the drawings]

FIG. 1 (a) is a front view of a film capacitor body held by a jig according to an embodiment of the method for manufacturing a film capacitor of the present invention, FIG. 1 (b) is a side view thereof, and FIG. )
FIG. 2 is an enlarged view of the AA 'part, FIG. 2 is a longitudinal sectional view of the chemical selective removal processing apparatus, FIG. 3 is a perspective view of another jig having increased cooling capacity, and FIG. FIG. 5 is a graph showing the relationship between the jig temperature and the dielectric film removal amount in the embodiment, FIG. 5 is a graph showing the relationship between the processing time and the jig temperature in the first and second embodiments, and FIG. 7 is an enlarged cross-sectional view of the film capacitor element plate, FIG. 8 is a process explanatory diagram of the method of manufacturing the film capacitor of the proposed example, and FIG. FIG. 9 (b) is an enlarged sectional view of the film capacitor element body, FIG. 10 (a) is a longitudinal sectional view of the chemical selective removal processing apparatus, FIG. 10 (b) )
Is a longitudinal sectional view of the chemically treated film capacitor body, FIG. 11 (a) is an explanatory view of the metallikon process, and FIG.
FIG. 11 (b) is an explanatory view of the electrode surface cutting step, and FIG. 11 (c) is an explanatory view of the cutting step. DESCRIPTION OF SYMBOLS 1 ... Film capacitor body, 2 ... Electrode lead-out part, 5 ... Dielectric film, 6 ... Laminated body, 14, 14 '... Jig

Claims (3)

(57) [Claims] 1. An end face of a film capacitor body while cooling by heat conduction a film capacitor body having a plurality of electrode metals and a dielectric film made of an organic material disposed between the electrode metals. A method of manufacturing a film capacitor, comprising: bringing a dielectric film of an electrode lead-out portion into contact with a gas that reacts with an organic material to chemically selectively remove an end of the dielectric film. 2. A step of masking the entire surface of the film capacitor body other than the electrode lead-out part, and laminating one or more of the masked film capacitor bodies with the electrode lead-out part in the same direction and a jig. And pressurizing and holding the film capacitor element through the jig while cooling the film capacitor body by heat conduction to bring the dielectric film of the electrode lead-out portion into contact with a gas reacting with an organic material and chemically selecting the film. Removing the film capacitor. 3. The method according to claim 1, wherein the film capacitor body is first heated to a certain temperature by heat conduction, and after reaching the predetermined temperature, the electrode lead portion of the dielectric film is chemically selectively removed while cooling. The method for producing a film capacitor according to claim 1 or 2, wherein