JPH04236411A - Capacitor fiber - Google Patents

Abstract

PURPOSE:To obtain a capacitor wherein the thickness of dielectric is thin, the size is very small, the weight is light, and the cost is low, by constituting a fiber of at least two electrode layer parts and a dielectric layer part interposing between the electrode layer parts, and completing-electrical connection by using external electrodes or lead wires. CONSTITUTION:A fiber type member constituted of two electrode layer parts 1, 3 and a dielectric part 2 interposing between them is connected with external electrodes or leads, thereby realizing capacitor function. Troubles that a thin film is apt to be broken, its dealing is difficult, and pin holes are apt to be generated can be avoided. In the title fiber, the dielectric layer can precisely, easily, and stably very thin, so that a very small-sized capacitor can be constituted.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates to capacitor fibers. More specifically, the present invention relates to a fiber having a capacitor function suitable for ultra-small capacitors used in integrated circuits and the like.

0002

BACKGROUND OF THE INVENTION In recent years, with the trend toward smaller and lighter electronic devices and higher density packaging, there has been an increasing demand for smaller electronic components. Various attempts have been made to consider and develop smaller film capacitors, but the capacitance of a capacitor increases as the permittivity of the dielectric increases and as the thickness of the dielectric decreases. For miniaturization, research and development have been focused on increasing the dielectric constant of the dielectric film and reducing the thickness of the dielectric film.

Conventionally, films made of polyethylene terephthalate, polypropylene, polystyrene, polycarbonate, polyphenylene sulfide, etc. have been mainly used as such dielectric films.
The thickness of these films is generally around 5 μm. A polyethylene terephthalate film with a thickness of around 1 μm has also been developed. However, films with a thickness of around 1 μm or even submicrons are extremely easy to tear and difficult to handle. In order to produce this film stably and at low cost on an industrial scale, many techniques must be solved. It is considered to be an extremely difficult task.

[0004] In addition, such a film capacitor is manufactured by winding at least two single-sided metallized films and pressing the wound body under heat so that the films are in close contact with each other. However, there were problems in that the capacitance and withstand voltage were unstable, and tan δ was likely to increase.

On the other hand, there is a method of using a coating thin film made of polycarbonate or the like as a dielectric material of a capacitor, or a method using vapor deposition, sputtering, plasma CVD, etc.
Proposals have been made to obtain thin film dielectric capacitors using solvent-free film forming methods such as D, but as the thickness of the coating thin film becomes thinner, there are problems such as a significant drop in voltage resistance due to pinholes. However, the solvent-free film forming method requires excessive equipment and is quite expensive, and there are many problems that remain in producing it stably and at low cost on an industrial scale. Ta.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems. That is, the present invention aims to provide an unprecedented ultra-small, lightweight, and low-cost capacitor by reducing the thickness of the dielectric material as much as possible based on a new idea.

[0007]

[Means for Solving the Problems] In order to achieve the above-mentioned object, as a result of intensive studies, the present invention has been arrived at.

In other words, the capacitor of the present invention has a different concept from conventional film capacitors, and skillfully utilizes special fiber technology (ultra-multilayer structure spinning technology) to create new ideas that have not been thought of before. It was discovered that the thickness of the dielectric material could be made ultra-thin, resulting in the fiber of the present invention.

That is, the fiber of the present invention has at least 2
The capacitor fiber is composed of two electrode layer portions and a dielectric layer portion interposed between the electrode layer portions, and has a capacitor function by being electrically connected with external electrodes or lead wires.

[0010] Further, in the condenser fiber of the present invention, a more effective and specifically preferred embodiment is as follows:
It has a multilayer composite structure in which dielectric layers and electrode layers are alternately arranged in a cross section perpendicular to the fiber axis direction.

Another preferred embodiment is one having a spiral composite structure in which dielectric layers and electrode layers are alternately arranged in a cross section perpendicular to the fiber axis.

[0012] Preferably, the electrode layer portion is composed of a low melting point metal or alloy or a spinnable polymer containing conductive fine particles.

Preferably, the electrode layer portion and the dielectric layer portion each have a thickness of 1 micron or less.

[0014]

[Operation] The present invention will be explained in more detail below. The capacitor fiber of the present invention is basically a fibrous material composed of at least two electrode layer portions and a dielectric layer portion interposed between them, and is electrically connected with external electrodes or lead wires. This is a fibrous material characterized by having a capacitor function. In the present invention, such fibrous materials are newly referred to as capacitor fibers.

[0015] By adopting such a configuration, it is possible to achieve ultra-miniaturization of the capacitor by reducing the thickness of the dielectric material, which was extremely difficult to achieve by extending the conventional technology.
Films are thin and easy to tear, difficult to handle,
In addition, the thickness of the dielectric layer can be made extremely thin in a dense, easy and stable manner without causing problems such as easy formation of pinholes, and the effects of the present invention have been achieved. The concept is completely different from the previous film capacitors.

The material constituting the electrode layer portion of the capacitor fiber of the present invention may be a low melting point metal such as zinc, tin, lead, bismuth, etc., or a lead-zinc alloy or a small amount thereof. It may be an alloy containing bismuth or the like, or it may be a spinnable polymer containing conductive fine particles.

[0017] Here, such conductive fine particles include conductive carbon, metal fine particles, conductive metal oxide fine particles,
Examples include conductive metal compound fine particles. Examples of conductive carbon include channel black, furnace black, acetylene black, etc., and examples of metal fine particles include fine particles of gold, platinum, silver, aluminum, copper, iron, zinc, nickel, chromium, and alloys thereof. be able to. Examples of metal oxide fine particles include fine particles of zinc oxide, tin oxide, copper oxide, cuprous oxide, indium oxide, tungsten oxide, and zurconium oxide, and examples of conductive metal compound fine particles include primary iodide.
Examples include fine particles of copper, zinc iodide, copper sulfate, cadmium sulfide, and the like.

The spinnable polymer may be any of various known spinnable polymers, including polyester, polyamide, polypropylene, polystyrene, polyphenylene sulfide, copolymer modified products thereof, and other components. Mixtures are preferred. The amount of the conductive fine particles contained in the spinnable polymer varies depending on the type of conductive fine particles used and is not particularly limited, but in the case of conductive carbon, it is in the range of 1 to 50% by weight. preferable.

The component constituting the dielectric portion interposed between the electrode portions of the capacitor fiber of the present invention is preferably a spinnable polymer, and such polymers include polyester typified by polyethylene terephthalate,
Examples include polypropylene, polystyrene, polyphenylene sulfide, polycarbonate, and fully aromatic polyesters synthesized by, for example, condensation of parahydroxybenzoic acid and naphthoic acid.

Rochelle salt, potassium dihydrogen phosphate, barium thiourea titanate, strontium titanate, magnesium titanate, lead titanate, and zirconium titanate are contained in the spinnable polymer as components constituting the dielectric portion. It is preferable to include fine particles having a high dielectric constant, such as acid lead, because this increases the dielectric constant of the dielectric layer.

The capacitor fiber of the present invention is composed of at least the above-mentioned two electrode layer portions and a dielectric layer portion interposed between the electrode layer portions, and the basic structure thereof is shown as a model in FIG. It was shown to. In the figure, 1 and 3 are opposite 2
2 represents an electrode layer portion, and 2 represents a dielectric layer portion, respectively.

In this basic configuration, it is preferable that the outer side of the fiber is formed so that a portion of the electrode layer is exposed on the surface of the fiber, as shown in FIG. 2, and the basic component is protectively surrounded. Such a surrounding configuration of the outer peripheral portion can also be preferably applied to the composite structure shown below. In the figure, 4 is a covering layer portion.

FIG. 3 shows a specifically preferred embodiment of the present invention in which this basic configuration is further developed in order to increase the capacitance, and in a fiber cross section perpendicular to the fiber axis direction, an electrode layer portion and a dielectric layer portion are This is a model of a multilayer composite structure in which layers are arranged alternately. In such a multilayer composite structure, the number of layers is not particularly limited, but is 10 to 1000.
It is preferable that the number of layers is zero.

Further, FIG. 4 shows a spiral composite structure in which electrode layer portions and dielectric layer portions are alternately arranged in a fiber cross section perpendicular to the fiber axis direction.

In these figures, the components constituting the electrode layer portions 1 and 3 and the dielectric layer portions 2 and 2' may be the same or may be composed of different types of components. Needless to say, it's a good thing.

[0026] By creating the composite structure shown in the model form in FIGS. 3 and 4, the effective dielectric layer area per unit fiber length can be expanded, and when viewed from the same fiber cross-sectional area, the dielectric layer It is more preferable because the thickness can be reduced and the capacitance can be increased.

[0027] The method for producing a capacitor fiber of the present invention has, for example, a plurality of channels, and one of the plurality of channels is
There is a method of directly melt-spinning multiple components simultaneously using a composite spinneret composed of tapered collecting parts that collect together, and a method that incorporates a static mixer as shown in Japanese Patent Publication No. 1048/1983. It may be manufactured using any other equipment, or may be manufactured by the method described below, without any particular limitation. For example, after at least two sets of dielectric layers and electrode layers are alternately arranged and wound to form a base capacitor structure, Heat at a temperature of
It can be obtained by winding the structure and discharging it in the axial direction from a cap having a tapered pore without substantially disturbing the base capacitor structure, cooling and solidifying it into a fibrous form. can. In this method, it is easy to form a very thin dielectric layer that is stretched in the fiber axis direction by spinning without using an extremely thin film-like material that is extremely difficult to handle as a dielectric layer. It becomes possible.

[0028] In this method, the electrode layer portion may be integrally formed in advance on the surface of the film-like material constituting the dielectric layer by a method such as vapor deposition, sputtering, or ion plating.

The capacitor fiber of the present invention can be obtained by cutting the fibrous material obtained by the method described above to an appropriate length, and further providing external electrodes, electrode extraction members, lead wires, etc. as necessary. By connecting , it can be used as an ultra-small capacitor.

[0030]

EXAMPLES The present invention will be explained in more detail with reference to examples below, but the validity and scope of the rights of the present invention are not limited or restricted by these examples. Rather, it brings about the next application and development. In addition, in the examples, all "proportions" are based on weight.

Example 1 Barium titanate was added and mixed with a copolymerized polyethylene terephthalate obtained by copolymerizing a part of 5-sodium sulfonate isophthalic acid as an acid component as a dielectric layer partial component. As shown in Fig. 2, nylon-6 mixed with 35% conductive carbon was used as the electrode layer component, and polyethylene terephthalate was used as the component constituting the outer periphery of the fiber as a protective layer. A monofilament was spun at a spinning temperature of 285° C. using a three-component composite spinneret with a fiber cross-sectional configuration as shown.

When the obtained fibrous material was cut into a length of 10 mm, the cross section of the fiber had a structure in which the electrode layer was partially exposed on the surface of the fiber, as shown in FIG.
When lead wires were connected to both electrode layer portions and a voltage was applied through the lead wires, it was confirmed that the capacitor functioned as a capacitor.

Example 2 A fluid mixer in which six fluid alternating array elements of the same type as those described in Japanese Patent Publication No. 1048/1988 were connected in the vertical direction, and a fluid discharged from two discharge holes of the fluid mixer was placed at the bottom of the fluid mixer. Copolymerization was carried out as a partial component of the dielectric layer in the same manner as in Example 1 using a spinning pack (the discharge hole shape is □ type) that was basically configured with a collection plate having a tapered shape that combined the Polyethylene terephthalate mixed with barium titanate was used, and the electrode layer component was nylon-6 mixed with 35% conductive carbon for melt spinning.

When the cross section of the obtained fiber was observed, it was found that each layer was uniform, the dielectric layer portion and the electrode layer portion were arranged alternately, and the fiber had a super multilayer composite structure with a cross-sectional shape similar to that shown in FIG. Ta. The total number of layers was 128 layers.

[0035] When the fibers with this ultra-multilayered composite structure were cut into a length of 10 mm and connected to external electrodes whose electrode parts could be connected alternately, and a voltage was applied, it was found that the fiber had an extremely excellent capacitor function. Met.

Example 3 A capacitor structure as a base body was created by laminating and winding two laminated composite film-like materials consisting of a dielectric layer made of polyethylene terephthalate and a conductive layer containing conductive fine particles. did.

Using the condenser structure as a matrix, a candle-like material was prepared under vacuum degassing, and then spun using a tapered monohole spinneret.

When the cross section of the obtained fibrous material was examined, it was found that
The spiral structure of the matrix was not substantially disturbed, and a fiber was obtained in which the conductive layer serving as the electrode layer portion and the polyethylene terephthalate layer serving as the dielectric layer were arranged alternately and had a spiral structure.

When the fibrous material was cut to a certain length and the electrode layer portion was connected to an external electrode, it was confirmed that it had a capacitor function.

[0040]

[Effects of the Invention] As is clear from the above, the capacitor fiber of the present invention is based on an unprecedented new idea by skillfully using spinning technology to make capacitors ultra-small and lightweight. This makes it possible to reduce costs and reduce costs, which has great industrial significance.

[Brief explanation of the drawing]

FIG. 1 is an external perspective model diagram schematically showing the basic structure of a capacitor fiber of the present invention.

FIG. 2 shows an example of the capacitor fiber of the present invention provided with a coating layer.

FIG. 3 is a model showing a multilayer composite structure of a preferred embodiment of the capacitor fiber of the present invention.

FIG. 4 is a model showing a spiral composite structure of a preferred embodiment of the capacitor fiber of the present invention.

[Explanation of symbols]

1, 3: Electrode layer part 2, 2': Dielectric layer part 4: Covering layer

Claims (5)

[Claims] Claim 1: A device comprising at least two electrode layer portions and a dielectric layer portion interposed between the electrode layer portions, and having a capacitor function by being electrically connected with external electrodes or lead wires. Characteristic capacitor fiber. 2. The capacitor fiber according to claim 1, which has a multilayer composite structure in which dielectric layers and electrode layers are alternately arranged in a cross section perpendicular to the fiber axis direction. 3. The capacitor fiber according to claim 1, which has a spiral composite structure in which dielectric layers and electrode layers are alternately arranged in a cross section perpendicular to the fiber axis direction. 4. The capacitor fiber according to claim 1, wherein the electrode layer portion is composed of a low melting point metal or alloy or a spinnable polymer containing conductive fine particles. 5. Claims 1 and 2, characterized in that each layer thickness of the electrode layer portion and the dielectric layer portion is 1 micron or less.
, 3 or 4.