JPS61154120A - Capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a capacitor with improved corona resistance.

(Structure of a conventional example and its problems) A cross-sectional view of a conventional metallized film capacitor is shown in FIG. In the figure, there is a gap 4 supported by a metallicon 3 between the dielectric film 1 and the vapor deposited electrode 2, which lowers the corona generation voltage and causes the electrode to deteriorate or scatter due to corona deterioration during practical use.

There was a tendency because the capacity reduction was large. Furthermore, if an antioxidant or a voltage stabilizer is mixed in to improve the corona resistance of the film, the tan δ will deteriorate, making it difficult to use a dry method in a high voltage region.

(Objective of the Invention) The object of the present invention is to eliminate the conventional drawbacks and improve corona resistance by forming a heat-adhesive resin layer mixed with an antioxidant and a voltage stabilizer on the surface of a dielectric film. The purpose of the present invention is to provide a capacitor with a high quality.

(Structure of the Invention) The capacitor of the present invention includes a heat-adhesive resin layer formed on at least one side of a film, an antioxidant or a voltage stabilizer mixed into the heat-adhesive resin layer, and the film used as a dielectric. It is something.

(Description of Embodiment) An embodiment of the present invention will be described based on FIGS. 2 to 6.

FIGS. 2 and 3 are cross-sectional views of a dielectric film according to an embodiment of the present invention.

In FIG. 2, one side has vapor-deposited metal, and a heat-adhesive resin layer 5 containing an antioxidant and voltage stabilizer effective for preventing corona deterioration is formed on the surface other than the vapor-deposited metal surface.

As the material of the dielectric film 1, polypropylene, polyester, polycarbonate, polysulfone, etc. are used.
As the vapor deposited metal 2, aluminum or zinc is used. The thermally adhesive resin layer 5 may be made of a mixture of low molecular weight polyethylene or polypropylene and their waxes;
Further, ethylene-vinyl acetate copolymers, block copolymers or mixtures of polyethylene or polypropylene with other polymers having polar groups, etc. are used. As corona-resistant additives, phenol-based additives are effective as antioxidants, and amine-based additives are effective as voltage stabilizers.

FIG. 3 shows a laminated film 1 in which a thermoadhesive resin layer 5 is formed when it is used together with a double-sided vapor-deposited electrode film; in this case, it is more effective to form it on both sides.

FIG. 4 is a sectional view of a capacitor using a single-sided vapor deposited film method according to the present invention, and FIG. 5 is a sectional view of a capacitor using a double-sided vapor deposited film method.

As a specific example, polypropylene (thickness: 6 microns) was used as the dielectric film, metal was coated with zinc on one side, Hirodyne 7514 (trade name) was dissolved in xylene as the heat-adhesive resin layer, and an antioxidant (trade name) was dissolved in xylene. Organizer [330) mixed with 2 PHR (mixing percentage based on 100 parts of resin), and voltage stabilizer N,
N'diphenylparaphenylenediamine at 0. IPH
Two types were prepared containing R. Then, it was applied to a dielectric film to form a film thickness of about 0.3 to 0.5 microns. A capacitor with a capacitance of about 5 μF was made using the above dielectric film, and its performance was examined.

FIG. 6 shows the results of measuring the temperature characteristics of tan δ.

In the same figure, a is a polypropylene film as the dielectric film, b is a film with 2 PHR of antioxidant mixed in, and C is a film with a voltage stabilizer mixed in at 0.1 PHR.
R mixed, d and e form a heat adhesive resin layer,
and add an antioxidant and a voltage stabilizer to it (2Pl) R,0,
It was mixed with I PHR.

This result shows that mixing an antioxidant or a voltage stabilizer into the film significantly deteriorates the tan δ characteristics.

Even when the above-mentioned modifier is mixed into the heat-adhesive resin layer as in the present invention, no significant decrease in tan δ is observed, and minute voids that occur between the films also occur inside and around the heat-adhesive resin layer. It is effective as a countermeasure against corona because of its large amount.

Note that the corona starting voltage is usually 250v to 300v, but by forming a thermoadhesive resin layer.

Increases to 400v to 450v.

(Effects of the Invention) According to the present invention, the corona starting voltage is increased, the occurrence of corona is extremely small, and therefore the decrease in life is reduced. Furthermore, there is almost no decrease in tanδ due to temperature,
This has the effect of making it possible to expand the dry method to high voltage areas.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional capacitor using a metalized film on one side, FIGS. 2 and 3 are cross-sectional views of a dielectric film according to the present invention, and FIGS. 4 and 5 are cross-sectional views of a capacitor according to the present invention. 6 are comparison diagrams of tan δ temperature characteristics of a conventional capacitor and a capacitor according to the present invention. 1... Dielectric film, 2... Vapor deposited metal. 3...Metallicon, 4...Gap, 5...Thermoadhesive resin layer. Patent applicant: Matsushita Electric Industrial Co., Ltd. Figure 1 Figure 2 Figure 4 Figure 3 Port Figure 5

Claims (1)

[Claims] forming a thermoadhesive resin layer on at least one side of the film;
A capacitor characterized in that an antioxidant or a voltage stabilizer is mixed into the heat-adhesive resin layer, and the film is used as a dielectric.