JP3085243B2 - Manufacturing method of capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is related to method for manufacturing a capacitor used for electronic equipment, electric equipment.

[0002]

2. Description of the Related Art Hitherto, a multilayer capacitor using an organic film as a dielectric is generally known as a film capacitor, and is formed by depositing aluminum on a film made of a material such as polypropylene, polyethylene terephthalate or polyethylene sulfide. Then, the metallized film was laminated by winding it on a flat plate or a roll. The laminated metallized film was subjected to hot pressing in a state of being laminated on a flat plate, whereby the film layers were bonded to form an element laminate. However, since this heat treatment eliminates voids between film layers and mechanically bonds the film, partial adhesion is caused by the surface roughness and wrinkles of the film, and the uniformity is lacking.

A method of manufacturing a capacitor of a type in which an organic film and an electrode metal are alternately laminated on a roll by a vacuum deposition method is that a laminate removed from a cooling roll is not subjected to a heat treatment as in the present invention. Was common.

[0004]

However, the conventional method for manufacturing a capacitor has the following problems. The laminate removed from the cooling roll is curved with a shape close to the curvature of the roll, and in the subsequent assembly process of the capacitor, there are problems in handling such as breakage and cracking when processing such as subdivision. I was

[0005] Further, since the heat treatment is not performed, the degree of curing of the resin layer is low and unstable, so that the adhesive force between the electrode metal layer and the resin layer is weak, causing variations. As a result, not only delamination such as cracking and swelling occurs in the subsequent processing, but also when the completed capacitor element is placed in a high-temperature and high-humidity atmosphere, moisture penetrates between the layers and the electrodes are corroded, thereby deteriorating the capacitance. Degradation occurs. If moisture invades into the other layer and is mounted on the substrate by flow or the like while being held in the device, there is a problem that mounting failure occurs due to cracking and swelling of the device due to high temperature during mounting.

The present invention solves the above-mentioned conventional problems by heat-treating a laminate of a resin and an electrode metal.
Strengthening of planarization and interlayer adhesion of laminates shall be the objective.

[0007]

In order to achieve this object, a method of manufacturing a capacitor according to the present invention comprises alternately laminating an electrode metal serving as an internal electrode and a resin layer serving as a dielectric on a cooling roll by vacuum evaporation. Then, the laminate is subjected to a heat treatment. Specifically, the laminate is obtained by curing the resin for each layer to a residual ratio of vinyl groups of 40 to 20% and then removing the laminate from the cooling roll. heat treatment while applying pressure and heat.

According to this manufacturing method, since the laminate is not completely cured but has flexibility by setting the residual ratio of vinyl groups to 40 to 20%, the laminated laminate curved by the pressure heat treatment can be flattened. And can be cured. When this flattened laminate is used in the assembly process after this process,
Mechanical processing such as subdivision can be easily performed. That is, there is no breakage or breakage when the laminate is subdivided into unit capacitors.

Further, the residual ratio of vinyl groups is reduced to 5 by heat treatment.
% Or less, the resin is almost completely cured, and the interlayer adhesion between the resin layer and the electrode metal of the laminated plate, which has undergone semi-curing and curing variation during vapor deposition and lamination, is uniformly strengthened, and a high-temperature and high-humidity atmosphere is provided. Even in the middle, the penetration of moisture between the layers is prevented. As a result, crack swelling during the assembling process and capacitance change due to electrode corrosion of the capacitor element are suppressed.

On the other hand, when the resin has a residual vinyl group content of more than 40% when it is taken out from the cooling roll, the laminate is too soft to handle as a plate, and the residual vinyl group content is low. If it is less than 20%, the flexibility of the laminated board is so small that it is difficult to flatten it, and therefore the productivity is poor and the performance of the capacitor is reduced.

When the degree of curing is high, the degree of freedom of chemical bonding of molecules is low, and the effect of strengthening adhesion is reduced. Therefore, the adhesion between the layers is poor, and the moisture resistance and the performance of the capacitor are deteriorated.

The residual ratio of vinyl groups after heat treatment is 5%.
In the case where it exceeds, flattening is possible, but sufficient adhesive strength cannot be obtained. Therefore, the adhesion between the laminations is poor,
The moisture resistance and the performance of the capacitor are reduced.

Further, the thickness of the laminate is 0.2 to 5
Outside the range of mm, when removing from the cooling roll,
When pressure is applied to a curved laminated plate, the element plate is easily broken.

As described above, according to the present invention, it is possible to obtain a flat laminated plate having strong interlayer adhesion, and as a result, it is possible to obtain a high-performance capacitor having good moisture resistance.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1) FIG. 4 shows an apparatus for manufacturing a capacitor according to the present embodiment. Oil vapor is sprayed onto a surface of a cooling roll 41 in a vacuum tank 46 by a margin forming unit 44 in a predetermined pattern. The electrode metal is evaporated and attached by the beam-based electric evaporation source 42 to obtain an electrode-deposited portion and a non-deposited portion by an oil pattern. The resin layer of a resin evaporation source 43 evaporates deposited thereon, the ultraviolet 45 is irradiated, it adjusts the vinyl group remaining ratio of the resin layer to a predetermined hardness. Margin forming unit 4
4. Each of the electric evaporation source 42 and the resin evaporation source 43 is provided with a shutter, and the adhesion of oil, metal, and resin is adjusted by opening and closing the shutter.

First, the inside of the vacuum chamber 46 is
After the pressure was set to × 10 Torr, the oil temperature of the margin forming unit 44 was set to 190 ° C., the electrode evaporation source 42 was set to a temperature having a predetermined evaporation rate, the temperature of the resin evaporation source 42 was set to 150 ° C. , The resin is evaporated in sequence. At this time, the cooling roll is rotated at a speed of 40 m / min, and an ultraviolet lamp of 230 W is irradiated from a distance of 100 mm. Actually, after the above conditions are stabilized, the margin shutter, the electrode evaporation source shutter , and the resin evaporation source shutter are opened to start lamination. The resin layers and the electrodes are alternately laminated every one rotation of the cooling roll. When a predetermined number of layers are reached, each shutter is closed and the operation of the cooling roll is stopped.

Next, the laminate is divided and removed from the cooling roll, and the curved laminate is sandwiched between metal plates 21 as shown in FIG. 2 and pressed so that the laminate 22 is flat.
Thereafter, the laminated plate is pressure-fixed with a metal plate and heat-treated in a high-temperature furnace. Then, external electrodes are attached so as to join the electrode metals of the laminated plate to obtain a laminated capacitor. Aluminum electrode metal 11 in this embodiment, the resin layer 12 using dimethylol cyclo diacrylate, 200 layers alternately stacked on a cooling roll, 0.9 mm
Was obtained. At this time, the double bond of the vinyl group is opened by ultraviolet rays to accelerate the curing reaction, and the residual ratio of the vinyl group is reduced to 25.
%. Then, the laminated plate was divided and removed from the cooling roll, and the curved laminated plate was sandwiched between metal plates 21, pressed and fixed at 3 kg / cm 2 so that the laminated plate 22 became flat, and heat-treated in a high-temperature furnace. The heat treatment condition at this time is 150
C. for 2 hours. Then, external electrodes were attached so as to join the electrode metals of the laminated plate to obtain a laminated capacitor.

FIG. 3 shows that the laminated board after heat treatment is used as a capacitor element and mounted on a printed circuit board.
5 is a graph in which a moisture resistance test was performed in a high-temperature and high-humidity tank of Example 1 to evaluate an adhesion state between layers.

The line 31 indicates a change in the capacitance of the element that has not been subjected to the heat treatment. Since the penetration of moisture between the layers is remarkable, the aluminum of the electrode is corroded and the capacitance is reduced at an early stage. The line 32 is an element subjected to the heat treatment in this embodiment, and has a strong adhesion between the layers, so that moisture hardly penetrates and the electrode is less corroded. Therefore, a high-performance capacitor having a low capacitance lowering time and good moisture resistance can be obtained.

FIG. 5 shows the structure of the capacitor.
2 and an electrode metal 51 having a margin 53 are alternately laminated, and an external electrode 54 is provided so as to connect the electrode metal.

Example 2 Dimethylol tricyclodecane diacrylate and 1.9-nonanediol diacrylate were mixed in the resin layer 12 at a ratio of 50% each, and were simultaneously deposited by vapor deposition. Aluminum was used for the electrode metal 11. Further, a 230 W ultraviolet lamp was irradiated from a distance of 150 mm for curing after the resin layer was adhered, and the residual ratio of vinyl groups was 3%.
0%. At this time, the number of laminations was set to 4500 and 2.0
mm of the laminate.

Thereafter, the treatment was performed in the same manner as in Example 1, as shown in FIG. 2, and the heat treatment conditions were 200 ° C. and 12 hours.

The state of adhesion between the layers was checked under the same conditions as in Example 1. As a result, as shown by the line 33 in FIG.

Similarly, dimethylol tricyclodecane diacrylate, 1,9-nonanediol diacrylate,
The heat treatment temperature was 150 ° C. for a laminate prepared using cyclohexane dimethylol divinyl ether alone or in combination with residual ratio of vinyl groups of 40% and 20%.
Similar results were obtained with capacitors that were run for 40 to 40 hours. Further, similar effects were obtained when the heat treatment temperature was in the range of 150 ° C. to 240 ° C.

Regarding the curing of the resin during the formation of the laminated film, not only the above-mentioned method but also the same effect was obtained by using an electron beam and an ultraviolet ray together. Similar effects were obtained when the pressure during the heat treatment was between 1.0 kg / cm @ 2 and 5.0 kg / cm @ 2.

[0027]

By the present onset bright as above, according to the present invention lever, it is possible to obtain a strong laminate planarity and interlayer adhesion, can realize excellent capacitor element thermal shock at the time of the humidity resistance and implementation.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a laminated board according to Embodiments 1 and 2 of the present invention.

FIG. 2 is a view showing a heat treatment method for a laminated board in Examples 1 and 2 of the present invention.

FIG. 3 is a diagram showing the moisture resistance characteristics of the capacitors obtained in Examples 1 and 2 of the present invention.

FIG. 4 is a view showing an apparatus for manufacturing a capacitor according to the first and second embodiments of the present invention.

FIG. 5 is a structural diagram of a capacitor according to the first and second embodiments of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 electrode metal 12 resin layer 21 pressurized metal plate 22 laminated plate of resin and electrode metal

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hisayoshi Watanabe 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-2-43042 (JP, A) JP-A-8- 115849 (JP, A) JP-A-62-245617 (JP, A) JP-B-46-1945 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01G 4/00-4 / 40 H01G 13/00-13/06

Claims (4)

(57) [Claims] 1. A resin layer serving as a dielectric and an electrode metal are alternately laminated on a cooling roll in a vacuum, and cured such that the residual ratio of vinyl groups in the resin layer is 40% to 20% for each layer. And forming a laminated plate, removing the laminated plate from the cooling roll, and heat-treating the laminated plate under pressure in the atmosphere. 2. A process according to claim 1 Symbol mounting capacitor resin dielectric is characterized by having at least a thermosetting. About wherein the temperature and time of the heat treatment, characterized in that it is a temperature and heat treatment time as the residual ratio of the vinyl groups of the resin is 5% or less, any one of claims 1-2 A method for manufacturing the capacitor as described in the above. The thickness of 4. A laminate characterized in that it is in the range of 0.2 mm and 5 mm, one of the claims 1-3 1
The method for producing a capacitor according to any one of the preceding claims.