JPH0824094B2 - Metallized film capacitors - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metallized film capacitor used in electronic devices and electric devices, and more particularly to a metallized film capacitor using a thin film.

[0002]

2. Description of the Related Art In recent years, efforts have been made to diversify and miniaturize electronic equipment and electric equipment, and electronic parts used for this are also required to be miniaturized and reduced in cost.
These demands are also strong for film capacitors.

Particularly, in a metallized film capacitor, a thin non-metallized portion (hereinafter referred to as a margin) is formed by thinning an organic film for miniaturization and a fine processing technique using a laser beam or a light beam. The electrode area is expanding.

A conventional metallized film capacitor will be described below with reference to the drawings. 4 to 6 show the structure of a conventional metallized film capacitor, in which 1 is a metallized film of 2.5 μm polyethylene terephthalate (hereinafter referred to as PET), 2 is a metallized portion, and 3 is a non-metalized film. Margin, which is a metallized portion, 4 is a boundary line,
Reference numeral 5 is a protrusion-shaped vapor-deposited metal, 6 is a vapor-deposited metal residue, and 7 is an external electrode.

As shown in FIG. 4, when a film having a thickness of several μm is used, the metallized portion 2 of the metallized film 1 is continuously irradiated with a laser beam or a light beam to form a linear margin 3. . Next, as shown in FIG. 5, a plurality of metallized films 1 were laminated, heat and pressure were applied, and external electrodes 7 were formed at both ends to obtain the metallized film capacitor shown in FIG.

[0006]

However, in the metallized film capacitor according to the above-described conventional process, when the margin 3 is formed on the metallized film 1 by the thermal energy of the laser beam or the light beam, the liquid phase is instantaneously liquefied. Due to the surface tension and the thermal stress, the deposited metal is aggregated and solidified on the boundary line 4 between the margin 3 and the metallized portion 2 to form a protrusion-shaped deposited metal (hereinafter, referred to as a working burr) 5. There has been a problem that the vapor-deposited metal residue 6 is scattered around. Therefore, when the metallized film 1 is laminated as shown in FIG. 5 and heat or pressure is applied to bond the layers to each other to form a laminated capacitor, a processing beam 5 or scattered vapor-deposited metal residue 6 may impair the film. It may cause dielectric breakdown. As a countermeasure for this, a method of limiting the size of the processing flash or removing it, as in Japanese Patent Application No. 1-216706 and Japanese Patent Application No. 1-236153, was considered, but the sufficient effect was not obtained. .

The present invention is to solve the above problems,
It is an object of the present invention to provide a metallized film capacitor having both miniaturization and high insulation.

[0008]

In order to achieve the above object, the metallized film capacitor of the present invention comprises a metallized film and a vapor-deposited metal continuously stripped by a laser beam or a light beam on the metallized film. The non-metallized processed part is removed to form a chain-shaped processed shape of 20 to 100 μm at the minimum processing width of the non-metalized processed part.

[0009]

Therefore, according to the present invention, the non-metallized portion in which the vapor-deposited metal is continuously removed in the form of a strip is formed into a chain shape, so that a machining flash that is aggregated and solidified on the boundary line between the margin and the metallized portion is formed. Since it does not form a straight line and exists along a chain-like boundary line, the processing flash becomes small, and the amount of evaporated metal dust scattered around is also small.

Normally, a film capacitor formed by using a thin film having a thickness of about several μm performs pulse irradiation when forming a non-metalized processed portion by a laser beam or a light beam. In this case, the processed shape is determined. What is done is the spot shape of one pulse, the pulse frequency, and the processing speed. By combining these three appropriately, a chain-shaped processed shape can be created. The chain-shaped processing shape reduces the area where the next pulse is again irradiated to the processing beam generated by the previous pulse, and the processing beam and the vapor-deposited metal residue are almost eliminated. As a result, the damage to the film is reduced, the withstand voltage characteristics and the productivity are improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is shown in FIG.
The same parts as those in FIG. 6 are designated by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

FIG. 1 is a plan view of a main part of a metallized film which constitutes a metallized film capacitor according to an embodiment of the present invention, FIG. 2 is a perspective view of the metallized films shown in FIG. 1 in a stacked state, and FIG. It is a principal part sectional drawing of a metallized film capacitor.

In the figure, 8 is a chain-shaped margin which is a non-metallized processed portion, A is a processing width of the minimum value portion of the chain-shaped margin 8, and B is a processing width of the maximum value portion. As shown in FIG. 1, the metallized film 1 is continuously irradiated with YAG (Nd ⁺ ) laser light at a spot shape of approximately 50 μm in a circle, a pulse frequency of 2.1 KHz, and a processing speed of 168 mm / sec. The part 2 is melted to form a chain-shaped margin 8. Minimum value A of chain-shaped margin 8
Has a width of 30 μm. Next, as shown in FIG. 2, the metallized films 1 are laminated so that chain-shaped margins 8 are alternately arranged, and heat is applied at 180 ° C. and a pressure of ² kg / cm ² is applied and pressed. After that, as shown in FIG. 3, zinc is metal sprayed from both ends to form the external electrodes 7. 100 metallized film capacitors produced in this manner were prototyped and used as samples of this example.

Similarly, as a comparative sample, the metallized film 1 was continuously irradiated with a substantially circular spot having a diameter of 35 μm, a pulse frequency of 5.6 kHz and a processing speed of 168 mm / sec to form a linear margin 3, and the same result was obtained. Through the steps, 100 metallized film capacitors were prototyped and used as a sample of the conventional example. The width of the linear margin 3 is set to be substantially the same as the width of the minimum value portion A of this embodiment, but the processed shape of the non-metallized portion is almost linear as compared with the chain of the sample of this embodiment. It looks like a strip.

Table 1 shows the results of carrying out the step-up breakdown test for each of 100 samples of the present example and the conventional example thus produced.

[0016]

[Table 1]

As can be seen from (Table 1), according to the structure of this embodiment, the yield is greatly improved as compared with the conventional example.

As described above, according to the above-described embodiment, by appropriately combining the spot shape, the pulse frequency and the processing speed to form the processed shape of the margin 8 into a chain shape, the metallization having excellent electrical characteristics and high productivity is obtained. A film capacitor can be provided.

When the minimum width A of this chain-like processed width is less than 20 μm on average, the discontinuous non-metallized processed portion is formed by the processing flash 5 and the vapor-deposited metal residue 6 and the electrical characteristics are deteriorated. I will end up. On the other hand, if the average exceeds 100 μm, the processing beam 5 and the vapor-deposited metal residue 6 become large,
Further, heat damage to the film is added, and the electrical characteristics are similarly deteriorated. Therefore, a chain-shaped margin 8 having a minimum value width A of 20 to 100 μm is most suitable.

If the ratio A / B of the minimum value point A and the maximum value point B of the chain-shaped processing width of the chain-shaped margin 8 is less than 0.2, it depends on the processing flash 5 and the vapor-deposited metal residue 6. If the discontinuous non-metallized processed portion 8 is formed and exceeds 0.8, not only the working flash becomes large, but also the amount of the vapor-deposited metal residue 6 greatly increases. Therefore, A / B is preferably 0.2 to 0.8.

[0021]

As is apparent from the above-mentioned embodiments, the present invention comprises a metallized film and a non-metallized processed portion obtained by continuously removing deposited metal in a strip shape on the metallized film by a laser beam or a light beam. It is possible to provide a metallized film capacitor having excellent electrical characteristics and high productivity by forming the non-metallized portion with a processing width of 20 to 100 μm at the minimum value in a chain shape. The effect is very large.

[Brief description of drawings]

FIG. 1 is a plan view of a metallized film according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a plurality of metallized films are laminated in one embodiment.

FIG. 3 is a cross-sectional view of a main part of a metallized film capacitor according to this example.

FIG. 4 is a plan view of a conventional metallized film.

FIG. 5 is a perspective view showing a state in which a plurality of metallized films in a conventional example are laminated.

FIG. 6 is a sectional view of a main part of a conventional metalized film capacitor.

[Explanation of symbols]

 1 metallized film 2 metallized part 8 chain-shaped margin (non-metallized part)

Claims (2)

[Claims] 1. A consists of a metallized film, a non-metallized processing unit the metallization was removed continuously strip by a laser beam or light beam over the metallized film, the non
20-100 μm at the minimum working width of the metallized part
A metallized film capacitor with a chain-like processed shape . 2. A / B = 0.2 to 0.8 where A is a minimum value portion and B is a maximum value portion of the chain-shaped processing width of the non-metallized processed portion. Metallized film capacitor.