JP2012142424A - Sealing body for capacitor, and capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sealing body excellent in adhesiveness between a base plate and rubber using technology for bonding a hard base plate to rubber by chemical bond.SOLUTION: The shapes of opening part of a metal case 1 and a sealing body for sealing it are formed into non-circular shapes such as an oval, an ellipse, or a compressed circular shape. Terminal insertion holes 5,5 larger than the outer diameters of lead terminals 4, 4 are formed in the base plate 2. Insertion hole inner surface parts 3c of rubber 3 bonded to the surface of the base plate are formed on the insides of the terminal insertion holes 5, 5, and airtightness between the lead terminals 4, 4 and the insertion holes 5, 5 is secured by this insertion hole inner surface parts 3c. Producing an OH group on the surface of the hard base plate such as a metal plate or a resin plate and using a dually functional organic compound having a reactive functional group to the OH group of the hard base plate and the rubber in the same molecule, the hard base plate is bonded to the rubber by chemical bond. In this case, the OH group is formed on the surface of the base plate 2, and 3-acryloxy-propyl-trimethoxysilane is reacted to the OH group. The base plate 2 is fixed in a die and the rubber 3 is charged in it to integrate both of them.

Description

The present invention uses a bifunctional organic compound that generates an OH group on the surface of a hard substrate such as a metal plate or a resin plate, and has a reactive functional group of the OH group of the hard substrate and rubber in the same molecule. The present invention also relates to a capacitor sealing body formed by integrating rubber using a technique of bonding a hard substrate and rubber by chemical bonding, and a capacitor including the sealing body.

  A capacitor sealing body in which rubber is bonded to a hard substrate such as a metal plate or a resin plate is described in Patent Document 1, for example. FIG. 5 is a cross-sectional view of the electrolytic capacitor described in Patent Document 1.

  In this electrolytic capacitor, the opening of the metal case 101 that houses the capacitor element 100 is sealed with a sealing body in which a resin substrate 102 and a rubber 103 are bonded together. The peripheral edge of the sealing body and the metal case 101 are fixed by caulking the upper edge of the metal case 101 toward the inside of the case.

  A tab 104 is pulled out from the upper part of the capacitor element 100, and the tab 104 is connected to a lower end portion of a rivet 105 penetrating the sealing body. The upper part of the rivet 105 protrudes from the surface of the sealing body, and an external terminal 106 is connected to the protruding part.

  In addition to the sealing body in which the rubber 103 is pasted on the entire surface of the substrate 102 as shown in FIG. 5, the patent document 1 discloses a capacitor in which the rubber 103 is pasted only around the crimped portion of the metal case 101 and the rivet 105. Is also described.

JP 2000-182908 A JP 2008-050541 A

  In the technique of Patent Document 1, a substrate 102 such as a metal plate or a resin plate and a rubber 103 are attached with an adhesive. However, the rubber 103 used for the sealing body is a material having excellent characteristics such as weather resistance, temperature resistance and long life, such as butyl rubber (particularly peroxide, vulcanized rubber, etc.). However, rubbers with poor adhesive properties cannot be used. For this reason, there is a problem that the types of rubber that can be used are limited.

  In particular, in the technique of Patent Document 1, even when the adhesion between the substrate 102 and the rubber 103 is inferior, the substrate 102 and the rubber 103 are pressure-bonded by the rivet 105 penetrating the crimped portion or the sealing body of the metal case 101. The sex is secured. In this case, in the case of the metal case 101 having a true circular opening, an equal force can be applied from the entire periphery of the metal case 101. However, when the opening of the metal case 101 is a non-circular shape such as an ellipse, an ellipse, or a flat shape as shown in FIG. 6, the caulking force can be applied equally between the long side and the short side. difficult.

  As a result, when the capacitor is used for a long period of time, the adhesion of the bonding surface between the substrate 102 and the rubber 103 is lowered, and there is a possibility that liquid leakage from the bonding surface between the substrate 102 and the rubber 103 may occur.

  In the technique of Patent Document 1, when the external terminal 106 is connected to the capacitor element 100, the joint surface between the substrate 102 and the rubber 103 is pressure-bonded using a rivet 105. However, the sealing of the sealing body using the rivet 105 and the external terminal 106 is troublesome to manufacture. For example, if a high degree of airtightness between the rubber 103 and the external terminal 106 can be ensured simply by inserting the external terminal 106 into the insertion hole provided in the sealing body, the capacitor can be manufactured more easily than the rivet 105. Become.

  However, in the prior art, the adhesion between the substrate 102 and the rubber 103 is low. Therefore, if the external terminal 106 is pressed into the insertion hole of the sealing body with a strong force, or the rubber 103 is pressed with a force when crimping the metal case 101 to bring the rubber 103 and the external terminal 106 into close contact with each other, There is a risk of causing peeling between the rubber 102 and the rubber 103.

The present invention has been proposed to solve the above-described problems of the prior art. An object of the present invention is to form an OH group on the surface of a hard substrate such as a metal plate or a resin plate, and to form a bifunctional organic compound having a reactive functional group of the OH group and rubber of the hard substrate in the same molecule. It is another object of the present invention to provide a capacitor and its sealing body having the following characteristics by bonding a substrate and rubber using a technique of bonding a hard substrate and rubber by chemical bonding.
(1) Liquid leakage from the interface between the hard substrate and rubber does not occur.
(2) Excellent airtightness between the metal case and the sealing body, or between the sealing body and the lead-out terminal passing through the sealing body.
(3) The structure is simple and manufacture is easy.

In order to achieve the above object, the capacitor and the sealing body of the present invention have the following technical features.
(1) An OH group is generated on the surface of a hard substrate such as a metal plate or a resin plate, and a bifunctional organic compound having a reactive functional group of the OH group and rubber of the hard substrate in the same molecule is used. Then, the sealing body is formed using a technique of bonding the hard substrate and rubber by chemical bonding.
(2) The shape of the sealing body is a non-true circle such as an ellipse, an ellipse, or a flat shape.

In the present invention, it is preferable to adopt the following configuration in addition to the above (1) and (2).
(3) A terminal insertion hole larger than the outer diameter of the extraction terminal is formed in the substrate, and a part of rubber bonded to the surface of the substrate is formed inside the terminal insertion hole. Ensure airtightness.

  In addition, after fixing the substrate in the mold, the sealing body used for the capacitor having the above configuration is filled with rubber in the mold and heated and pressurized to join the substrate and rubber. Integration is also an embodiment of the present invention.

In this case, an OH group is generated on the surface of a hard substrate such as a metal plate or a resin plate, and a bifunctional organic compound having a reactive functional group of the OH group and rubber of the hard substrate in the same molecule is used. The following can be used as a technique for bonding the hard substrate and rubber by chemical bonding.
(1) OH groups are generated on the surface of the substrate by means such as corona discharge treatment, atmospheric plasma treatment, and UV irradiation.
(2) The substrate on which the OH group is generated is brought into contact with a bifunctional organic compound having a reactive functional group, for example, a 3-acryloxypropyltrimethoxysilane solution, and an acryloxy group is generated on the surface by a chemical bond.
(3) A substrate having an acryloxy group formed on the surface by chemical bonding is washed and dried as necessary.
(4) After fixing the substrate in the mold, the mold is filled with rubber, and heated and pressurized at 80 to 250 ° C. to integrate the substrate and rubber.
(5) As the rubber, it is preferable to use ethylene propylene rubber or silicone rubber in consideration of adhesion to a hard substrate.

  The corona discharge treatment of the surface of the substrate uses various types of corona surface modification devices, for example, “Corona Master” manufactured by Shinko Electric Measurement Co., Ltd., for example, power supply: AC 100 V, output voltage: 1 to 20 kV, oscillation frequency: The treatment can be performed at 10 to 40 kHz for 0.1 second to 60 seconds and at a temperature of 0 to 60 ° C.

  Atmospheric pressure plasma treatment uses various types of atmospheric pressure plasma generators such as “Aiplasma” manufactured by Matsushita Electric Works, Ltd., for example, plasma treatment speed of 10 to 100 mm / s, power source: 200 to 220 V / AC (30 A). Compressed air: 0.5 MPa (1 NL / min), 10 kHz / 300 W to 5 GHz, power: 100 W to 400 W, irradiation time: 0.1 second to 60 seconds.

  For UV irradiation, various types of UV-LED irradiation devices, for example, “UV-LED irradiation device ZUV-C30H” manufactured by OMRON Corporation, for example, wavelength: 200 to 400 nm, power source: 100 V / AC, light source peak illuminance : 400 to 3000 mW / cm2, irradiation time: 1 to 60 seconds.

  As a means for adhering the substrate and the bifunctional organic compound having a reactive functional group, the substrate is immersed in a solution of the bifunctional organic compound having a reactive functional group, and spraying, brushing, or roll coating is performed. Can be used.

  In addition, as a solution of a bifunctional organic compound having a reactive functional group, a bifunctional organic compound having a reactive functional group is mixed with alcohols such as water, methanol, ethanol, isopropanol, ethylene glycol or diethylene glycol, Ketones such as acetone or methyl ethyl ketone, esters such as ethyl acetate, halides such as methylene chloride, olefins such as butane or hexane, ethers such as tetrahydrofuran or butyl ether, aromatics such as benzene or toluene, dimethylformamide or Amides such as methyl pyrrolidone or the like, or those dissolved in a mixed solvent thereof can be used.

  After the contact treatment between the substrate and the bifunctional organic compound having a reactive functional group, it is usually desirable to heat dry the resin surface at 40 to 200 ° C. for 1 to 30 minutes or to wash with the above solvent. In this case, the substrate surface to which the bifunctional organic compound having a reactive functional group is attached is heated and dried by, for example, an oven, a dryer, or high-frequency heating. Heat drying is normally performed for 1 to 60 minutes in the temperature range of 50 degreeC-200 degreeC. Below 50 ° C., it takes too long for the OH groups to react with the polymer material formed on the surface. If it exceeds 200 ° C., the substrate surface is deformed or decomposed, which is not preferable. Moreover, it is good also as reduced pressure drying instead of heat drying. Drying under reduced pressure is suitable for a substrate having poor heat resistance.

  According to the present invention, an OH group is generated on the surface of a hard substrate such as a metal plate or a resin plate, and the bifunctional organic compound has a reactive functional group of the OH group and rubber of the hard substrate in the same molecule. Since a sealing body was formed by bonding a hard substrate and rubber using chemical bonding technology using a molecular adhesive, the adhesive strength between the substrate and rubber was much higher than that of the conventional technology. To improve. As a result, there is no risk of peeling of the substrate and the rubber even when a strong force is applied to the rubber when the metal case is crimped or when the extraction terminal is press-fitted. As a result, liquid leakage due to peeling between the substrate and the rubber is eliminated, and the life and / or stabilization of the capacitor can be increased.

  In addition, when rubber is placed on the inner surface of the insertion hole provided on the board, the rubber on the inner surface of the insertion hole is pulled out by using the force applied to the rubber on the board surface when the metal case is crimped or when the extraction terminal is press-fitted. The terminals can be firmly adhered, and the airtightness of the lead-out terminal portion can be ensured by simple press-fitting without using rivets as in the prior art.

Sectional drawing of the metal case upper edge part and sealing body part in 1st Embodiment. Sectional drawing of the sealing body in 2nd Embodiment. Sectional drawing of the metal case upper edge part and sealing body part in 3rd Embodiment. Sectional drawing of the metal case upper edge part and sealing body part in 4th Embodiment. Sectional drawing of the capacitor | condenser described in patent document 1. FIG. The perspective view of the capacitor | condenser which has a non-round metal case and a sealing body.

(1) 1st Embodiment FIG. 1: is sectional drawing of the metal case upper edge part and sealing body part in 1st Embodiment. The capacitor of this embodiment includes a capacitor such as an electrolytic capacitor or an electric double layer capacitor. The capacitor is a non-true circle (oval) as shown in FIG. 6, and FIG. 1 is a cross-sectional view taken from a direction parallel to the long side. Other non-true circles include an oval, an ellipse, a substantially rectangular shape with curved corners, and other oval shapes.

  In the present embodiment, an opening of a metal case 1 containing a capacitor element (not shown) is formed by using an aluminum substrate 2 and ethylene propylene rubber (EPDM) 3 on the surface of a hard substrate such as a metal plate or a resin plate. And is sealed with an integrated sealing body by a technique in which a bifunctional organic compound having a reactive functional group of OH group and rubber of a hard substrate is bonded in the same molecule by chemical bonding. The peripheral edge of the sealing body and the metal case 1 are fixed by caulking the upper edge of the metal case 1 toward the inside of the case.

  A pair of lead terminals 4 and 4 with one end connected to the capacitor element and the other end protruding outside the capacitor are mounted on the sealing body. A pair of insertion holes 5 and 5 are provided in the substrate 2 for mounting the lead terminals 4 and 4. The insertion holes 5 and 5 are set to be slightly larger than the outer diameter of the lead terminals 4 and 4.

  The ethylene propylene rubber 3 is inserted from the upper surface 3a covering the entire upper surface of the substrate 2, the lower surface 3b covering the entire lower surface, the insertion hole inner surface 3c covering the entire inner surface of the insertion holes 5 and 5, and the surface of the upper surface 3a. Cylindrical portions 3d and 3d rising continuously from the hole inner surface portions 3c and 3c are provided. The cylindrical portion is for insulating and isolating the metal case from the lead terminal. The inner diameters of the insertion hole inner surface portions 3c, 3c are set to be the same as or slightly smaller than the outer diameter of the extraction terminals 4, 4 inserted into the insertion hole inner surface portions 3c, 3c. The dimensions are press-fit.

  The upper surface portion 3a of the ethylene propylene rubber 3 has substantially the same thickness as that of the substrate 2 and is made of ethylene by pressure applied to the end surface of the upper surface portion 3a (the contact surface with the inner surface of the metal case 1) and the surface peripheral portion of the upper surface portion 3a. The propylene rubber 3 is deformed and sealed.

  A positioning groove 1 a for locking the sealing body is formed at the mounting position of the sealing body in the opening of the metal case 1. The positioning groove 1a is formed by pressing the wall surface of the metal case 1 inward by pressurizing the outer periphery of the metal case 1 by caulking. The sealing body is positioned on the metal case 1 by engaging the peripheral edge portion of the lower surface portion 3b of the ethylene propylene rubber 3 constituting the sealing body with the positioning groove 1a.

Note that in a thin capacitor such as an oval shape as in the first embodiment or a flat shape corresponding thereto, as shown in FIG. 6, a portion (short side) having a large curvature at both ends in the opening of the metal case 1. Protrusion 1c may be provided on the side. Since the strength of the exterior case 1 is high at the portion with a large curvature (short side portion), the protruding portion 1c can be provided stably.

  The upper edge portion 1b of the metal case 1 is curved downward by caulking, and the tip portion (lower end portion in the figure) is in contact with the peripheral portion of the upper surface portion 3a of the ethylene propylene rubber 3. In this case, the upper edge portion 1b is pressed with a strong force against the upper surface portion 3a by the caulking force, thereby deforming the upper surface portion 3a. Thereby, the upper edge part 1b of the metal case 1 and the upper surface part 3a of the ethylene propylene rubber 3 are in close contact with each other, and the airtightness between the peripheral part of the sealing body and the metal case 1 is also ensured.

  In the sealing body of this embodiment having such a configuration, the substrate 2 and the ethylene propylene rubber 3 are made to generate OH groups on the surface of a hard substrate such as a metal plate or a resin plate as described above, and hard within the same molecule. Using a bifunctional organic compound having a reactive functional group between the OH group and rubber of the substrate, the hard substrate and rubber are integrated by a technique of bonding by chemical bonding. That is, the substrate 2 on which OH groups are generated on the surface is brought into contact with a 3-acryloxypropyltrimethoxysilane solution to generate acryloxy groups on the surface by chemical bonding. The substrate 2 is mounted in a mold, the ethylene propylene rubber 3 is filled in the mold, and heated and pressurized, whereby the substrate 2 and the ethylene propylene rubber 3 are integrally molded.

  Thus, in this embodiment, OH groups are generated on the surface of a hard substrate such as a metal plate or a resin plate with respect to the aluminum substrate 2, and the reactivity between the OH groups of the hard substrate and rubber in the same molecule. Since the ethylene propylene rubber 3 is bonded by a technique in which a hard substrate and rubber are bonded by chemical bonding using a bifunctional organic compound having a functional group, the adhesive force between the substrate 2 and the ethylene propylene rubber 3 is increased. Compared with the case where the conventional adhesive is used, it is much higher. For example, in the case of a conventional industrial epoxy adhesive, the tensile shear strength is 3 to 4 MPa, but in this embodiment, it can be 7 MPa or more (evaluation based on JIS standard K6850). As a result, liquid leakage from the interface between the substrate 2 and the ethylene propylene rubber 3 can be prevented, and the life of the capacitor can be extended.

  In addition, since the adhesive force between the substrate 2 and the ethylene propylene rubber 3 has been improved, even the non-circular capacitor for which it is difficult to apply the caulking force evenly can be applied to the metal case 1 with a caulking force stronger than that of the prior art. By pressing the upper edge portion 1b against the ethylene propylene rubber 3, it is possible to secure the sealability of the portion where it is difficult to apply force with the prior art.

  As a result of using an aluminum plate having a higher strength than the resin substrate as the substrate 2, in the non-true circular capacitor as in this embodiment, even when an external force is applied from the central portion of the long side, which is weak in strength. The aluminum substrate 2 receives the force. As a result, there is no deformation of the metal case 1, and a capacitor excellent in strength can be obtained.

(2) Second Embodiment FIG. 2 is a cross-sectional view of a sealing body in a capacitor according to a second embodiment. This embodiment is different from the first embodiment in the following points, but other configurations generate OH groups on the surface of a hard substrate such as a metal plate or a resin plate, and the OH of the hard substrate in the same molecule. Including the adhesion between the substrate 2 and the ethylene propylene rubber 3 by a bifunctional organic compound having a reactive functional group of a group and rubber, the same as in the first embodiment.
(1) The ethylene propylene rubber 3 is not laminated on the lower surface of the substrate 2.
(2) The upper surface portion 3a of the ethylene propylene rubber 3 is not provided with the cylindrical portions 3d and 3d for insulating and isolating the metal case and the lead terminal.
(3) The thickness of the substrate 2 is thinner than that of the ethylene propylene rubber 3.

  Also in the present embodiment, the sealing body is fixed to the metal case 1 by the same means as in the first embodiment. In that case, due to the caulking force of the upper edge 1 b of the metal case 1, the adhesion between the metal case 1 and the peripheral edge of the sealing body, and the inner surface portions 3 c and 3 c of the ethylene propylene rubber 3 and the lead terminals 4 and 4. Is secured.

(3) 3rd Embodiment FIG. 3: is sectional drawing of the metal case upper edge part and sealing body part in 3rd Embodiment. In this embodiment, a stepped portion 2a is formed on the upper surface side of the outer peripheral portion of the substrate 2, and a portion of the ethylene propylene rubber 3 is filled in the stepped portion 2a to form the outer peripheral surface portion 3e.

  In the present embodiment, the upper edge portion 1b of the metal case 1 is curved and pressed against the peripheral edge portion of the upper surface portion 3a of the ethylene propylene rubber 3, and the lateral crimping groove 1c is formed in parallel with the positioning groove 1a. By caulking the lateral caulking groove 1c toward the outer peripheral surface portion 3e of the ethylene propylene rubber 3, the upper edge portion of the metal case 1 and the peripheral edge portion of the sealing body are sealed.

  In this case, the peripheral edge of the aluminum substrate 2 abuts against the inner surface of the metal case 1 and receives the caulking force from the outside of the metal case. That is, the peripheral edge portion of the substrate 2 acts as an inner mold during the horizontal caulking operation. As a result, the positioning and shape accuracy of the lateral caulking groove 1c can be ensured, and the dimensional accuracy of the groove is improved.

(4) 4th Embodiment FIG. 4: is sectional drawing of the metal case upper edge part and sealing body part in 4th Embodiment. In the present embodiment, ethylene propylene rubber 3 is generated on the surface of a hard substrate such as a metal plate or a resin plate at the insertion hole 5 partial extraction terminal portion provided in the substrate 2, and the OH group of the hard substrate is formed in the same molecule. Using a bifunctional organic compound having a reactive functional group of a rubber and rubber, using a sealing body integrated by a technique of bonding a hard substrate and rubber by chemical bonding, the sealing body and the metal case 1 are The laser welding part 6 is connected. In this case, an aluminum member capable of laser welding to the metal case 1 is used as the substrate 2.

  According to 4th Embodiment which has such a structure, the crimping operation | work with the metal case 1 and a sealing body becomes unnecessary, and manufacture of a capacitor | condenser becomes easy. In particular, when using a non-circular metal case as shown in FIG. 6, the laser welded part is fixed equally in either direction without being affected by the size of the diameter as in the caulking operation. Therefore, the sealing property between the metal case 1 and the sealing body is excellent. Further, as a modification of the fourth embodiment, sealing between the metal case 1 and the sealing body by caulking as described above and fixing means by a laser welded portion as shown in FIG. 4 can be used in combination.

(5) Other Embodiments The present invention is not limited to the embodiment as described above, and includes other embodiments as described below.
(a) Make the metal case or sealing body into a perfect circle.
(b) In addition to the ethylene propylene rubber 3, other rubber materials such as isobutylene isoprene rubber and styrene butadiene rubber, regular butyl rubber, partially crosslinked butyl rubber, and silicone rubber can be used as the rubber. Of these, ethylene propylene rubber and silicone rubber are preferred in view of adhesion to a hard substrate.

(c) Use a metal plate other than aluminum or a resin plate such as bakelite, phenol, or epoxy as the substrate.
(d) A rivet as shown in FIG. 5 can also be used as a lead-out terminal.
(e) Capacitors can be applied to electrolytic capacitors and electric double layer capacitors.

  Next, an OH group is generated on the surface of a hard substrate such as a metal plate or a resin plate, and the bifunctional organic compound having a reactive functional group of the OH group and rubber of the hard substrate in the same molecule is used. A technique for bonding the substrate 2 and the ethylene propylene rubber 3 will be described according to an embodiment.

Example 1
A capacitor was produced using the sealing body shown in the first embodiment (FIG. 1).
An aluminum substrate (2 mm) was used as the substrate, and ethylene propylene rubber (2 mm) was used as the rubber.
An aluminum substrate (2 mm) was washed with ultrasonic waves in acetone at 20 ° C. for 10 minutes and dried with a dryer as a sample.
The ethylene propylene rubber (2 mm) compound is EP inch 100 parts, HAF carbon black 50 parts, stearic acid 1 part, zinc oxide 5 parts, dicumyl peroxide (DCP, crosslinker) 3 parts 8 inch roll And mixed to adjust.
The aluminum substrate (2 mm) was washed for 10 minutes at 20 ° C. under ultrasonic irradiation in acetone, and then in an alkaline degreasing solution (SK-144, 50 g / L aqueous solution manufactured by Ebara Eugene Corporation) at 70 ° C. for 5 minutes. Washing and finally washing in distilled water under ultrasonic irradiation at 25 ° C. for 10 minutes and drying with a dryer were used. Subsequently, using a corona discharge surface treatment apparatus (Corona Master, manufactured by Shinko Electric Measurement Co., Ltd.), 25 ° C., gap length 20 mm, moving speed 1 m / min, discharge voltage 10 kV, atmospheric atmosphere (relative humidity: 60%) The aluminum substrate (2 mm) was processed under the conditions described above.

A corona discharge-treated aluminum substrate (2 mm) was immersed in a 3-acryloxypropyltrimethoxysilane (1 mol / L-ethanol) solution for 10 minutes, heated at 100 ° C. for 10 minutes, and then ethanol and distilled water on the surface. Was ultrasonically washed for 10 minutes each and sufficiently dried to obtain a 3-acryloxypropyltrimethoxysilane-bonded aluminum substrate (2 mm).
After fixing this 3-acryloxypropyltrimethoxysilane bonded aluminum substrate (2 mm) in the mold, filling the mold with rubber, heating at 160 ° C. and pressurizing at 10 MPa, the substrate and rubber Were integrated to create the sealing body shown in the first embodiment (FIG. 1).
The capacitor element was impregnated with an electrolyte solution of solvent: ethylene glycol, solute: ammonium adipate, and the capacitor element was housed in an aluminum case, and the open end of the aluminum case was crimped and sealed with a sealing body.

(Comparative Example 1)
Instead of the bifunctional organic compound having the reactive functional group of the first embodiment, a capacitor was produced using a normal rubber vulcanizing adhesive. The vulcanized adhesive for rubber consists of two layers, a top coat and a base coat. The top coat uses Toyo Chemical Research Laboratories (product name Metalock: F-16), the film thickness is 10 to 20 μm, and the base coat is Toyo Chemical. Using a laboratory (product name Metallock: PH-50), the film thickness was 5 to 15 μm. Other configurations were the same as in Example 1 except that the adhesive was brushed.

Ten capacitors of Example 1 and Comparative Example 1 were prepared, and the mass change (g) of the capacitor after elapse of 1000 hours and 2000 hours under 105 ° C. no-load condition was measured and compared with the initial mass. In addition, the capacitances of the capacitors of Example 1 and Comparative Example were compared with the initial capacitance. Moreover, the surface state of the capacitor | condenser of Example 1 and a comparative example was observed, and the presence or absence of the liquid leakage of the electrolyte solution from the site | part of a sealing body was confirmed. In addition, about mass change and CAP change rate, the average value of the capacitor | condenser of Example 1 and the comparative example 1 is shown.

  As shown in Table 1, it can be seen that the capacitor of Example 1 has less change in mass of the capacitor after 1000 hours and after 2000 hours than the capacitor of Comparative Example 1. Further, in Comparative Example 1, the electrolyte solution adhered to the surface of the sealing body (near the interface between the sealing body and the extraction terminal) after 2000 hours, and liquid leakage occurred, whereas in Example 1, It can be seen that there is no liquid leakage in the capacitor, and the sealed state of the capacitor is good.

  DESCRIPTION OF SYMBOLS 1 ... Metal case, 1a ... Positioning groove, 1b ... Upper edge part, 1c ... Lateral caulking groove, 2 ... Board | substrate, 2a ... Step part, 3 ... Rubber, 3a ... Upper surface part, 3b ... Lower surface part, 3c ... Insertion hole inner surface Part, 3d ... cylindrical part, 3e ... outer peripheral surface part, 4 ... extraction terminal, 5 ... insertion hole, 6 ... laser welded part

Claims (8)

  OH group is generated on the surface of the hard substrate, and the hard substrate and rubber are bonded by chemical bond using a bifunctional organic compound having a reactive functional group of OH group and rubber of the hard substrate in the same molecule. Capacitor sealing body.   2. The capacitor sealing body according to claim 1, wherein the shape of the sealing body is a non-circular shape such as an ellipse, an ellipse, or a flat shape.   A bifunctional organic compound having the reactive functional group is interface-bonded to the substrate on which the OH group is generated on the surface by a silane coupling reaction to generate an acryloxy group on the surface of the substrate. 3. The capacitor seal according to claim 1, wherein the substrate and the rubber are integrated by heating and pressurizing after filling the mold with rubber after being fixed in the mold. body.   The encapsulant for a capacitor according to claim 3, wherein the bifunctional organic compound having a reactive functional group is 3-acryloxypropyltrimethoxysilane.   5. The substrate having the OH group formed on the surface is formed by treating the substrate surface by any one of corona discharge treatment, atmospheric plasma treatment, and UV irradiation. Capacitors for capacitors described in 1.   The capacitor sealing body according to any one of claims 1 to 5, wherein ethylene rubber or silicone rubber is used as the rubber.   A capacitor in which an opening of an outer case containing a capacitor element is sealed by the capacitor sealing body according to claim 1. A terminal insertion hole larger than the outer diameter of the extraction terminal is formed in the hard substrate, and a part of the rubber bonded to the surface of the substrate is formed inside the terminal insertion hole. With this rubber, the airtightness between the extraction terminal and the insertion hole is formed. The capacitor according to claim 7, wherein: