JPS596498B2 - Manufacturing method of multilayer capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a multilayer capacitor in which protrusions projecting in the thickness direction of the film are formed on the edges of the film to be thermally sprayed with metal.

A method for producing a multilayer capacitor includes, for example, a method in which a double-sided metallized film and a non-metalized film are slit into a single capacitor configuration width, wound and laminated on a drum, subjected to metal spraying, and then cut with a saw. A wide composite film with a dielectric layer formed on one or both sides of a double-sided metallized film is rolled and laminated and pressed to form a flat plate, and then the non-metalized part (deposition margin part) of the double-sided metalized film is cut with a knife. There is a method of slitting the material, applying metal spraying to the slit surface, and then cutting it with a saw.

Multilayer capacitors do not consist of continuous long electrodes like conventional wound capacitors, but instead have a structure in which short electrodes corresponding to the cutting width are independently stacked as many as the number of laminated layers.

Therefore, metal spraying for drawing out lead wires is most important. If the contact between the vapor deposited electrode and the sprayed metal is incomplete, the electrode will separate from the sprayed metal, resulting in a decrease in capacitance and tan δ
causes an increase in

In order to solve this problem, the present inventor has already proposed a capacitor with a structure in which protrusions are formed on the edge of the film in the direction of its thickness to create a gap between the films, making it easier for the sprayed metal to enter. (Japanese Patent Application No. 53-5410 (Japanese Unexamined Patent Publication No. 54-98955)).

The present invention proposes a manufacturing method thereof.

As a method for forming the above-mentioned protrusions, for example, a method as shown in FIG. 1 is used.

In the figure, 1 is a composite film in which a dielectric layer is formed on both sides of a double-sided metallized film having a plurality of capacitor electrodes, 2 is a protrusion forming roller having regular protrusions on the outer periphery,
3 is a rubber roller, 4 is a delivery body for the composite film 1, 5
is a winding body of a flat bobbin.

FIG. 2 is a cross-sectional view showing the position of the protrusion forming portion of the composite film 1. FIG.

The composite film 1 is composed of a substrate film 6, a metallized portion 7 made of a vapor-deposited metal, a non-metalized portion (deposition margin) 8, a dielectric layer 9, and a dielectric layer margin 10, and the protrusions are formed on the vapor deposition margin as shown in the figure. It is formed in the center of 8.

To form the protrusions, as shown in FIG. The rollers 2 and 3 are continuously rotated in synchronization with each other in the direction of arrow B.

Thereafter, they are wound up on a flat bobbin winding body 5 and laminated.

FIG. 3 shows a cross section of the entire composite film wound and laminated on the roll 5 in this manner.

11 force button - a protrusion formed by 2, the protrusion 11
The overall growth is shown by the formation of .

After winding and laminating, heat pressing is performed to facilitate subsequent processing and to stabilize capacitor characteristics.

The object of the present invention is this pressing method.

Conventionally, a hydraulic press device is used as a pressing method, and in this case, the press plate has a groove to prevent pressing a metal flat plate as shown in Figure 4A, or a protruding part as shown in Figure 4A. Grooved metal plates have been used.

However, when a flat metal plate is used, the raised portions caused by the protrusions shown in FIG. 3 are crushed, and the effect of forming the protrusions is halved.

On the other hand, when a grooved metal plate is used, the raised protrusion remains almost unchanged and the desired effect appears, but it is difficult to align the protrusion forming part with the groove of the grooved metal plate, resulting in poor workability. It was extremely bad.

For this reason, the development of a new pressing method has been desired.

The pressing conditions according to the present invention include: [1] the electrode-facing portion can be pressed without crushing the protrusion-forming portion;

il) There is no need for alignment and the workability is good.

The present invention proposes a pressing method that can solve the above conditions, and is characterized by using an elastic body filled with gas.

This will be explained below with reference to the drawings.

FIG. 5 is a cross-sectional front view of an apparatus capable of carrying out the pressing method of the present invention, in which 1 is a composite film wound and laminated on a roll 5, 12 is an elastic body that encloses gas 13, and 14 is a heater. It is a heating plate with 15 built-in.

The elastic body 12 is mounted on the hot platen 14 with its surroundings sealed, and a gas injection port 16 is also provided in the hot platen 14.

The heating platen 14.degree. 14 is fixed to a fixed base 17 and a movable base 18 that is movable by hydraulic pressure.

The rolled body 5 in which the composite film 1 is wound and laminated is first placed on a support stand 19.

Thereafter, the base 18 equipped with the push-up jig 20 is pushed up in the direction of arrow C by the hydraulic device, and the rolled body 5 is moved onto the upper and lower heating platen 1.
Fix it approximately at the center of 4°14.

At this time, the elastic body 12 is in the position shown by the dashed line because the gas 13 is not enclosed.

Subsequently, when gas is fed through the sealing port 16 and raised to a predetermined pressure, the elastic body 12 expands and assumes the shape shown by the solid line along the shape of the laminated composite film 1.

If the hot platen 14, 14 is heated in this state and held for a certain period of time, an ideal pressed state can be obtained in which the electrode facing part is pressed while maintaining the raised part of the protrusion forming part 11.

In this way, the present invention presses the laminated composite films using gas pressure through an elastic body, without crushing the pre-formed protrusions, and also allows for alignment with the laminated composite films. The present invention provides a pressing method that is extremely easy to work with and does not require any process.

A rubber sheet with a thickness of 0.3 to 1.5 mm is suitable for the elastic body 12, and among them, silicone rubber is most suitable since it is used at high temperatures.

Next, specific examples of the present invention will be described.

Using a composite film in which a 1 μm thick polycarbonate layer was formed by lacquering on both sides of a double-sided metallized polycarbonate film with a thickness of 4 μm and a width of 5' 00 mm, the method was as shown in FIGS. 1 and 2. , average 7
500 mm on a flat bobbin (600 mm x 30 (h++ m
One tan-wound layer was laminated.

Subsequently, heat pressing was performed using the method of the present invention shown in FIG.

A 0.5 mm silicone rubber sheet was used as the elastic body, and compressed air from a compressor was used as the gas.

The temperature of the hot platen was maintained at 110° C.±2° C., the air pressure within the rubber sheet was maintained at 2 kg/criY, and the sheet was pressed for 30 minutes.

For comparison, heat pressing was also carried out using the conventional method shown in FIG.

The conditions at this time were 1100C±2℃, press pressure 2kg/
C11t, the time was 30 minutes.

After pressing, the plate-shaped laminated film is cut off from the flat bobbin, and then, as shown in FIG.
A plate-shaped capacitor body similar to the opening in the figure was formed.

The slit surface of each capacitor body was sprayed with Zn metal, and then cut in a direction perpendicular to the slit direction using a milling blade to make a new capacitor.

The capacitance of a single capacitor was 0.27 μF.

Next, lead wire welding was performed, and after epoxy exterior treatment, the characteristics of the three were compared.

The test was a charging/discharging test at a DC voltage of 100 Ω and a charging/discharging resistance of 2Ω, and the evaluation was performed based on the number of charging/discharging times until the capacitance reached the initial value of 97.

The results are shown in the table below. As described above, the multilayer capacitor manufactured by the method of the present invention has characteristics comparable to those using the grooved press plate shown in Figure 4, and considering that no alignment is required at all, this method is suitable. The pressing method according to the invention can be said to be the most excellent method.

As is clear from the above explanation, the manufacturing method according to the present invention
In the manufacturing of multilayer capacitors, which are laminated with protrusions formed on the edges to be metal sprayed, from the viewpoint of capacitor characteristics,
This is an extremely useful method from the viewpoint of workability, and has great effects both technically and economically.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing the method for forming protrusions on a composite film, Figure 2
The figure is a cross-sectional front view of the main part, FIG. 3 is a cross-sectional view after the composite film is wound and laminated, and FIG. 4 A. The openings are a cross-sectional view of a conventional heat press plate, FIG. 5 is a cross-sectional front view of the apparatus showing the pressing method in the manufacturing method of the present invention, and FIG. FIG. 3 is a perspective view before and after cutting. DESCRIPTION OF SYMBOLS 1... Composite film, 2... Protrusion forming roller, 5... Winding body, 6... Tip plate film, 7... Metal Metalized part, 8... Non-metalized part, 9... Dielectric layer, 11...
Protrusion, 12...Elastic body, 13...Gas, 14...Heating plate, 15...Heater.

Claims (1)

[Claims] 1. A wide composite comprising a dielectric layer formed on at least one side of a wide metalized film in which metalized parts and non-metallized parts are alternately formed on the surface of a substrate film to form a plurality of capacitor electrode arrays. After forming protrusions protruding in the thickness direction of the film in each of the non-metalized parts of the film, the film is wound up with a wide width, hot pressed, and the non-metalized parts are slit to form a plate-shaped capacitor body. A method for manufacturing a multilayer capacitor in which the cross section of the slit is then subjected to metal spraying, and then cut into single capacitors, the method of manufacturing a multilayer capacitor is characterized in that the multilayer capacitor is pressed with an elastic body filled with gas in the pressing step. Production method.