WO2018168845A1 - Ceramic composite sheet and capacitor - Google Patents

Abstract

Provided are: a ceramic composite sheet that, while improving the withstand voltage, is capable of more reliably preventing peeling between ceramic composite sheets in which a dielectric layer is laminated on a metal foil; and a capacitor comprising said ceramic composite sheet. A ceramic composite sheet 1 is overlapped to constitute a capacitor, and is configured so as to have a dielectric layer 3 containing an organic resin and a dielectric ceramic powder laminated on a metal foil 2, and so as to have an electrically conductive layer 4 laminated on the dielectric layer 3.

Description

Ceramic composite sheet and capacitor

The present invention relates to a ceramic composite sheet in which a dielectric layer containing an organic resin and a dielectric ceramic powder is laminated on a metal foil, and a capacitor including the same.

The ceramic capacitor is formed by laminating a dielectric layer mainly composed of dielectric ceramic powder such as barium titanate particles and an internal electrode layer made of metal such as nickel. Ceramic capacitors have a high dielectric constant and high heat resistance. However, the ceramic capacitor has low toughness of the dielectric layer, and is easily broken by electrostriction deformation.

The metallized film capacitor is formed by depositing a metal such as aluminum on the surface of a dielectric film made of an organic resin such as a polyamide-imide resin. The metallized film capacitor has a high potential gradient of the dielectric layer, and is soft and tough. However, the metallized film capacitor has a low capacity density and low heat resistance.

In order to compensate for the shortcomings of ceramic capacitors and metallized film capacitors, and to draw out the advantages of each other, sheet-like ceramic composite capacitors having a dielectric layer containing dielectric ceramic powder and organic resin have been developed. For example, a dielectric layer containing a dielectric ceramic powder and an organic resin is prepared by mixing a dispersion of a dielectric ceramic powder and a dispersion of an organic resin, applying the mixture to a metal foil such as an aluminum foil, and drying the solvent by heat treatment. Is formed on the metal foil, and the metal foil is further superposed on the dielectric layer and adhered by applying heat and pressure to produce the sheet-shaped ceramic composite capacitor.

The sheet-shaped ceramic composite capacitor has a problem that the dielectric layer and the metal foil easily peel off. The reason is that a sufficient amount of organic resin does not exist on the surface of the dielectric layer, and the adhesive force is insufficient by the thermocompression bonding simply utilizing the thermoplasticity of the organic resin. To solve this problem, a dielectric layer is formed on one metal foil, an organic resin slurry is applied to the other metal foil to form an organic resin film, and the dielectric layer and the organic resin film face each other with heat and heat. A method of applying pressure has been proposed (see, for example, Patent Document 1). By interposing the slurry-like organic resin film, the organic resin comes into close contact with the metal foil, the air layer disappears inside the organic resin, and the organic resins are thermocompression-bonded, so that the adhesion is increased.

JP-A-3-236210

It is desirable that the capacitor has a high withstand voltage so as not to cause a short circuit even under severe conditions where an abnormal voltage exceeding the rated voltage is applied. Therefore, in order to increase the withstand voltage of the dielectric layer, it is desirable that the particles contained in the dielectric layer have a certain size or more. When an organic resin film is selected as the binder for closely attaching the dielectric layer and the metal foil, the organic resin film functions as a dielectric layer in the capacitor. The particles contained in the film are also regulated to a certain size or more as the dielectric layer.

That is, if a sufficient withstand voltage is desired, the surface of the organic resin film cannot be made highly smooth due to the presence of large particles in the organic resin film, and the adhesion between the organic resin film and the metal foil is reduced. End up. Therefore, a dielectric layer is formed on one metal foil, an organic resin slurry is applied to the other metal foil to form an organic resin film, and heat and pressure are applied to the dielectric layer and the organic resin film facing each other. In the method, the withstand voltage was improved, and the adhesion between the organic resin film and the metal foil could not be sufficiently increased, and the metal foil could not be reliably peeled off.

In order to solve the above-described problems of the prior art, the present invention provides a ceramic composite that can more reliably prevent peeling between ceramic composite sheets in which a dielectric layer is laminated on a metal foil while improving withstand voltage. It is providing a capacitor | condenser provided with a body sheet and the said ceramic composite sheet.

In order to achieve the above object, a ceramic composite sheet according to the present invention comprises a metal foil, a dielectric layer laminated on the metal foil and containing an organic resin and a dielectric ceramic powder, and the dielectric layer. And a conductive layer to be laminated. The conductive layer is not subject to restrictions such as an organic resin film that requires voltage resistance, and can be designed with emphasis on adhesion to the metal foil, and can prevent the metal foil from peeling more reliably.

For example, the conductive layer may include a conductive material having a tabular grain shape. Since the flat conductive material is in surface contact with the metal foil, the contact area with the metal foil is larger than that of the spherical particles, and the conductive layer containing the flat conductive material is in close contact with the metal foil.

The conductive layer may further include a conductive material having a spherical particle shape. By interposing the conductive material having a spherical particle shape while maintaining the adhesion with the metal foil, the conductive material is interposed between the conductive materials having a flat particle shape, and the conductivity is increased.

The content of the dielectric ceramic powder in the dielectric layer may be 70 wt% or more and 97.5 wt% or less with respect to the content of the organic resin. Below this lower limit, the dielectric layer containing a large amount of voids results in a reduction in withstand voltage. On the other hand, if this upper limit is exceeded, it becomes a dielectric layer containing many cracks and voids, and instead of lowering the withstand voltage, it is difficult to use it as a dielectric layer in the worst case.

The organic resin may be a polyamide-imide resin, and the dielectric ceramic powder may be a barium titanate powder. The conductive layer may include graphite and carbon black.

A capacitor including this ceramic composite sheet is also an aspect of the present invention, and the capacitor of the present invention includes the plurality of ceramic composite sheets.

According to the present invention, since it is a ceramic composite sheet that can be laminated through a conductive layer treated as an electrode, the adhesion of the ceramic composite sheet can be increased.

The ceramic composite sheet of this embodiment is shown, (a) is a top view, (b) is sectional drawing. It is a cross-sectional schematic diagram of a capacitor | condenser provided with the ceramic composite sheet of this embodiment. It is a schematic diagram which shows the manufacturing process of the winding type capacitor of a 1st example. It is a schematic diagram which shows the manufacturing process of the winding type capacitor of a 2nd example. It is a schematic diagram which shows the manufacture process of the chip type capacitor of a 1st example. It is a schematic diagram which shows the manufacturing process of the chip type capacitor of a 2nd example. It is a photograph which shows the state of various dielectric material layers. It is a graph which shows the dielectric constant of various dielectric material layers.

Hereinafter, embodiments of the ceramic composite sheet according to the present invention and various capacitors including the ceramic composite sheet will be described in detail.

(Ceramic composite sheet)
As shown in FIG. 1, the ceramic composite sheet 1 is formed by laminating a metal foil 2, a dielectric layer 3, and a conductive layer 4. A dielectric layer 3 is formed on one side of the metal foil 2, and a conductive layer 4 is formed on the dielectric layer 3. The conductive layer 4 of the ceramic composite sheet 1 and the surface of the metal foil 2 of another ceramic composite sheet 1 or the metal foil 2 that does not form the dielectric layer 3 or the conductive layer 4 face each other. In addition, a winding type or multilayer chip type capacitor is produced.

The metal foil 2 has a thickness of 5 μm to 50 μm, for example. The metal foil 2 is mainly made of a conductive material. The conductive material is aluminum (Al), nickel (Ni), copper (Cu), silver (Ag), gold (Au), iron (Fe), palladium (Pd), platinum (Pt), zinc (Zn), One kind selected from precious metals and base metals such as tin (Sn) or chromium (Cr), or an alloy thereof. The surface of the metal foil 2 is preferably subjected to a roughening treatment such as etching in order to improve the adhesion with the dielectric layer 3 by the anchor effect.

The dielectric layer 3 has a thickness of 10 to 30 μm, for example. The dielectric layer 3 contains organic resin and dielectric ceramic powder dispersed as main components. Since the dielectric ceramic powder is contained in the dielectric layer 3, the dielectric constant of the ceramic composite sheet 1 can be increased. In addition, since the dielectric layer 3 contains an organic resin, the dielectric gradient of the ceramic composite sheet 1 can be increased and the toughness can be increased. The organic resin and the dielectric ceramic powder preferably have an average particle size of more than 0.1 μm from the viewpoint of improving the withstand voltage of the capacitor.

The organic resin is one or a mixture of two or more selected from polyamideimide, polyetherimide, polyimide, polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyphenylene sulfide, polyvinylidene fluoride, and the like.

In addition to barium titanate (BaTiO ₃ ) -based ceramics, the dielectric ceramic powder includes a part of Ba substituted with Ca and Sr and a part of Ti substituted with Zr (Ba, Ca, Sr) (Ti, Zr). ) One or a mixture of two or more selected from O ₃ ceramics, for example, barium titanate (BaTiO ₃ ), strontium titanate (SrTiO ₃ ), calcium titanate (CaTiO ₃ ), titanate magnesium (MgTiO ₃₎ system, calcium zirconate (CaZrO ₃₎ system, calcium titanate zirconate (PCZT) system, barium zirconate (BaZrO ₃₎ system, and titanium oxide (TiO ₂₎ system.

The manufacturing process of this dielectric layer 3 is illustrated. For example, a mixed solution is prepared by mixing barium titanate with N-methyl-2-poloridone (NMP) as a dispersion solvent at a ratio of 1: 1 by weight. Also, a mixed solution is prepared by mixing NMP in a ratio of 1: 4 parts by weight of NMP as a dispersion solvent in polyamideimide. The dispersion solvent of both mixed liquids can be selected in consideration of the suppression of aggregation of the dielectric ceramic powder, and the same kind is desirable. These mixed liquids are mixed at a ratio of 1 part by weight to 0.1 or more and 1.0 or less.

Then, this mixed solution of barium titanate and polyamideimide is applied to a metal foil 2 such as an aluminum foil subjected to surface roughening treatment to a thickness of 10 μm to 30 μm. However, a strip-shaped uncoated portion 2 a is left on one side of the metal foil 2. As a coating method, various known methods such as gravure coating, die coating, and screen printing can be used. After the coating is completed, heat treatment is performed at 100 to 120 degrees Celsius, and the solvent is dried. Note that after the solvent is dried, a press treatment may be performed to increase the density of the dielectric layer 3.

Here, the content of the dielectric ceramic powder in the dielectric layer 3 is desirably 70 wt% or more and 97.5 wt% or less with respect to the content of the organic resin. If it is less than 70 wt%, the effect of increasing the dielectric constant by including the dielectric ceramic powder in the organic resin is reduced. In addition, the dielectric layer 3 includes many voids, and the withstand voltage is reduced due to the voids. Therefore, when it is going to produce the dielectric material layer 3 with content of dielectric ceramic powder less than 70 wt% with respect to content of organic resin, the process of removing a space | gap is added or only the part without a space | gap is used. Necessity arises and the yield deteriorates. On the other hand, if the content exceeds 97.5 wt%, the dielectric layer 3 becomes a so-called tattered state in which many cracks and voids are generated, and the dielectric strength is lowered in the worst case. It becomes difficult to use.

It is speculated and not limited to this mechanism, but it is considered that the lower limit and the upper limit existed in terms of voids and cracks in the content of the dielectric ceramic powder because of the following reasons.

First, the organic resin becomes an adsorbent and a binder during the mixing process of both liquid mixtures. That is, the organic resin covers the particle surface of the dielectric ceramic powder and increases the affinity with the solvent. In addition, the organic resin covering the surface of the dielectric ceramic powder particles bonds the dielectric ceramic powders together with the organic resin as a medium. In addition, when the amount of the dielectric ceramic powder is small, in other words, when the amount of the organic resin is large, a large amount of the organic resin is present between the particles of the dielectric ceramic powder due to the function as a binder. Existed and the organic resin foamed during the mixing process. Therefore, it is considered that the dielectric layer 3 having many voids has been produced after the mixed solution is dried.

On the other hand, when the amount of the dielectric ceramic powder is large in the mixing process of both the mixed liquids, in other words, when the amount of the organic resin is small, the organic resin functions as an adsorbent and the particle surface of the dielectric ceramic powder is reduced. Although the organic resin cannot cover the function as a binder sufficiently, the dielectric layer 3 after the liquid mixture is dried becomes tattered and there are many cracks and voids. It is thought that it has been.

The conductive layer 4 has a thickness of 0.5 μm to 5 μm, for example. The conductive layer 4 includes a conductive material as a main component. The conductive material is one or a mixture of two or more selected from natural or artificial graphite, carbon black, carbon nanotubes, graphene, ketjen black, and acetylene black. The average particle size of the conductive material is desirably 15 μm or less, and it is desirable that the conductive layer 4 contains a plate-shaped particle-shaped conductive material. The plate-like particle-shaped conductive material is disposed on the surface of the conductive layer 4 in a state where the flat plate surface and the surface of the metal foil 2 are parallel to each other. Therefore, since the plate-like conductive material having a particle shape is in surface contact with the metal layer 2, the contact area with the metal foil 2 is widened, and a large adhesion can be obtained. More preferably, in addition to the tabular grain-shaped conductive material, a spherical grain-shaped conductive material is included. The spherical particle-shaped conductive material is interposed between the tabular particle-shaped conductive materials, and the conductivity between the tabular particle-shaped conductive materials is increased.

The flat plate has a flat flat plate surface, the short side length of the flat plate surface is 0.5 to 10 μm, the long side length is 0.5 to 10 μm, and the thickness is 0.00. The shape of 5 or more and 2 μm or less includes a sphere, an ellipsoid, a polyhedron, or a shape formed by overlapping and connecting these.

This conductive layer 4 fixes a conductive material in the layer using an elastomer such as styrene-butadiene rubber (SBR) as a binder. For example, a slurry in which flat graphite and spherical carbon black are mixed at a weight ratio of 10: 1 using pure water as a dispersion solvent, and styrene / butadiene rubber is added at a ratio of 1 as a binder is prepared, and a dielectric is prepared. It is applied on the body layer 3 with a thickness of 0.5 to 5 μm. When the coating is finished, heat treatment is performed and the solvent is dried.

(Capacitor)
As shown in FIG. 2, the ceramic composite sheet 1 is stacked so that the conductive layer 4 and the metal foil 2 are in contact with each other, and a plurality of sheets are stacked. By applying pressure, the conductive layer 4 and the metal foil 2 are in close contact with each other, and a capacitor is manufactured.

(First winding type capacitor example)
For example, as shown in FIG. 3A, a pair of long ceramic composite sheets 1 in a strip shape are aligned with the longitudinal direction and the short direction aligned, but with the direction of the uncoated portion 2a reversed. That is, the uncoated portion 2a where the dielectric layer 3 and the conductive layer 4 are not coated is prevented from overlapping. Moreover, it superimposes so that the metal foil 2 of the other ceramic composite sheet 1 may be placed on the conductive layer 4 of one ceramic composite sheet 1.

As shown in FIG. 3B, the pair of laminated ceramic composite sheets 1 are wound so as to wind the dielectric layer 3 side. Thereby, the cylindrical capacitor | condenser element 61 by which a pair of ceramic composite sheet 1 was wound is formed.

As shown in FIG. 3 (c), an electrode metal is vapor-deposited by metallicon on the end faces of the uncoated portion 2a exposed at both ends of the cylindrical body, and on one end face of the positive electrode side electrode part 5-1, A negative electrode portion 5-2 is formed on the other element end face. Thus, each element end face is composed of different electrodes. In this case, the electrode metal may be a metal that can be soldered for ease of connection, such as soldering. For example, a metal such as zinc or a tin alloy may be used as the solderable metal. In addition, for example, an alloy of aluminum and zinc, an aluminum and tin alloy, or a zinc and tin alloy may be used as a solderable metal.

The electrode portions 5-1 and 5-2 are connected to the positive external terminal 64-1 and the negative external terminal 64-2 provided on the terminal plate 67 by lead wires 63. That is, the positive electrode part 5-1 and the positive electrode external terminal 64-1, and the negative electrode part 5-2 and the negative electrode external terminal 64-2 are connected by solder using the lead wire 63. At this time, as shown in FIG. 3D, the lead wire 63 connected to the negative external electrode 64-2 passes through the hollow portion of the capacitor element 61 and the negative external terminal 64-2 is disposed. It is pulled out to the surface and connected to the negative external terminal 64-2.

As shown in FIG. 3D, after the lead wire 63 is connected to the positive external terminal 64-1 and the negative external terminal 64-2, the capacitor element 61 is housed in the case 65 and insulated in the case 65. The winding type capacitor is manufactured by filling the functional resin 66 and performing a curing process.

(Second winding type capacitor example)
As shown in FIG. 4A, the uncoated portions 2a of the pair of long ceramic composite sheets 1 in a strip shape are cut at predetermined intervals to form tabs 2b in the longitudinal direction. The pair of ceramic composite sheets 1 are overlapped with the longitudinal direction and the lateral direction aligned, and the tabs 2b aligned. Moreover, it superimposes so that the metal foil 2 of the other ceramic composite sheet 1 may be placed on the conductive layer 4 of one ceramic composite sheet 1.

As shown in FIG. 4B, a pair of laminated ceramic composite sheets 1 are wound around the conductive layer 4 side to form a cylindrical capacitor element. At one end of the capacitor element, a positive electrode portion 5-1 protruding from the end face of the capacitor element is formed by a tab 2b-1 of one ceramic composite sheet 1, and the other ceramic composite sheet 1 is formed. The tab 2b-2 forms a negative electrode portion 5-2 protruding from the end face of the capacitor element, and the electrode portions 5-1 and 5-2 are formed to face each other.

After being connected to the electrode portions 5-1 and 5-2 of this capacitor element and the external terminals provided on the sealing plate, they are housed in a case, filled with a sealing resin and subjected to a curing treatment, and a wound capacitor Is produced.

(First chip type capacitor example)
As shown in FIG. 5 (a), a plurality of rectangular ceramic composite sheets 1 are overlaid so that the uncoated portions 2a face alternately and the dielectric layers 3 and the conductive layers 4 are stacked. . As shown in FIG. 5B, the conductive layer 4 and the metal foil 2 are in close contact with each other without sandwiching the air layer, and the upper and lower ceramic composite sheets 1 are firmly laminated.

As shown in FIG. 5C, the laminate is molded with resin so that the uncoated portion 2a protruding to one side is exposed. A metal such as copper is applied to the exposed surface of the uncoated portion 2a of the laminate to form external electrodes 68a and 68b. The external electrodes 68 a and 68 b are formed on the two opposing surfaces of the laminate of the ceramic composite sheet 1. As a result, a multilayer chip capacitor in which a plurality of ceramic composite sheets 1 are laminated is produced.

(Second chip type capacitor example)
As shown in FIGS. 6A and 6B, a metal foil 6 such as an aluminum foil is superposed on the conductive layer 4 side of the ceramic composite sheet 1. In the metal foil 6, the dielectric layer 3 and the conductive layer 4 are not formed like the ceramic composite sheet 1. The ceramic composite sheet 1 and the metal foil 6 are overlapped so that the metal foil 6 protrudes on the opposite side of the ceramic composite sheet 1 from the uncoated portion 2a. Then, when heat and pressure are applied to the laminate of the ceramic composite sheet 1 and the metal foil 6, the conductive layer 4 and the metal foil 6 are laminated without sandwiching the air layer.

6 (c), the laminate is molded with resin so that one end of the metal foil 6 protruding to one side and the uncoated portion 2a are exposed. A metal such as copper is applied to the exposed surface of the uncoated portion 2a of the laminate to form external electrodes 68a and 68b. It is formed on the two opposing surfaces of the laminate of the ceramic composite sheet 1. Thereby, a chip-type capacitor formed by connecting one ceramic composite sheet 1 and one metal foil 6 is produced.

(Function and effect)
As described above, in this ceramic composite sheet 1, the dielectric layer 3 containing the organic resin and the dielectric ceramic powder is laminated on the metal foil 2, and the conductive layer 4 is laminated on the dielectric layer 3. I made it.

Since the conductive layer 4 is handled as an electrode in the capacitor, it is not necessary to restrict the contained particles of the conductive layer 4 in consideration of the withstand voltage unlike the dielectric layer 3. Therefore, the adhesiveness between the conductive layer 4 and the metal foils 2 and 6 can be enhanced, and both high withstand voltage and suppression of peeling can be achieved.

In particular, a conductive material having a tabular grain shape may be included in the conductive layer 4. Since the flat conductive material is in surface contact with the metal foils 2 and 6, the contact area with the metal foils 2 and 6 is larger than that of the spherical particles, and the conductive layer 4 containing the flat conductive material is made of metal. Strongly adheres to the foils 2 and 6.

The conductive layer 4 may further include a conductive material having a spherical particle shape. The conductivity between the conductive materials having a flat particle shape is increased by interposing the conductive material having a spherical particle shape while maintaining the adhesion to the metal foil, and the metal foils 2 and 6 and the conductive layer are increased. The conductivity with 4 is increased.

Also, since the dielectric layer contains dielectric ceramic powder, a capacitor having a high dielectric constant can be produced. Furthermore, since the dielectric layer contains an organic resin, a capacitor having a high dielectric gradient and high toughness can be manufactured.

In this embodiment, the organic resin is a polyamide-imide resin, the dielectric ceramic powder is a barium titanate powder, and the conductive layer 4 contains graphite and carbon black. I can't.

Further, in this embodiment, the pair of ceramic composite sheets 1 is created by superimposing the aluminum foil 2 of the other ceramic composite sheet 1 on the conductive layer 4 of the ceramic composite sheet 1. In order to further increase the thickness, a pair of ceramic composite sheets 1 may be integrated by applying heat and pressure, or a silver paste may be interposed between the ceramic composite sheets 1. .

Further, various dielectric layers 3 in which the weight ratio of the dielectric ceramic powder and the organic resin was changed were actually produced, the dielectric constant of the dielectric layer 3 was measured, and the state of the dielectric layer 3 was observed. In the production of the dielectric layer 3, barium titanate is used as the dielectric ceramic powder, and N-methyl-2-poloridone (NMP) is mixed in a ratio of 1: 1 by weight with barium titanate as a dispersion solvent. Was prepared. Moreover, the liquid mixture which mixed many NMP in the ratio of the weight part 1: 4 by weight of NMP as a dispersion | distribution solvent was used for polyamideimide as organic resin.

And these both liquid mixtures were mixed so that it might become the following weight ratio, and various liquid mixture was obtained. That is, the first mixed liquid in which barium titanate is 65 wt% with respect to polyamideimide, the second mixed liquid in which barium titanate is 70 wt% with respect to polyamideimide, and the barium titanate is 80 wt% with respect to polyamideimide. A third mixed solution with a percentage of barium titanate of 90 wt% with respect to the polyamideimide, a fifth mixed liquid with a barium titanate of 97.5 wt% with respect to the polyamideimide, and A sixth mixed solution in which barium titanate was 98.0 wt% with respect to polyamideimide was obtained.

These first to sixth mixed liquids are applied to an aluminum foil by a doctor blade method, subjected to heat treatment at 90 degrees Celsius for 30 minutes to dry the solvent, obtain each dielectric layer 3, and photograph the state. In addition, the relative dielectric constant was measured. The results are shown in FIGS. FIG. 7 is a photograph of the dielectric layer 3 obtained with the first and sixth mixed liquids. FIG. 8 is a graph showing the relative dielectric constant of the dielectric layer 3 obtained with each liquid mixture.

As shown in FIG. 7A, the dielectric layer 3 derived from the first mixed liquid in which barium titanate is 65 wt% with respect to the polyamideimide has many voids V. In addition, foaming was seen in the mixing process of this 1st liquid mixture. As shown in FIG. 7B, the dielectric layer 3 derived from the sixth mixed liquid in which barium titanate is 98.0 wt% with respect to the polyamideimide has cracks C, which are in a so-called tattered state. there were. On the other hand, no void was found in the dielectric layer 3 derived from the second to fifth mixed liquids in which barium titanate was within 70 to 97.5 wt% with respect to the polyamideimide.

From the result of this state observation, it is desirable that the content of the dielectric ceramic powder in the dielectric layer 3 is 70 wt% or more and 97.5 wt% or less with respect to the content of the organic resin. Can be obtained.

Further, as shown in FIG. 8, the relative dielectric constant is 70 wt% when the content of the dielectric ceramic powder in the dielectric layer 3 is 70 wt% or more and 97.5 wt% or less with respect to the content of the organic resin. % Relative permittivity (ε _s ) averaged 34.5, 80 wt% relative dielectric constant 43.1 on average, 90 wt% relative dielectric constant 52.2 on average, 97. The relative dielectric constant at 5 wt% is 60.3 on average and increases in proportion to the increase in dielectric ceramic powder. On the other hand, if it deviates from the range of 70 wt% or more and 97.5 wt% or less, the relative dielectric constant is rapidly decreased.

As a result, it is desirable that the content of the dielectric ceramic powder in the dielectric layer 3 is 70 wt% or more and 97.5 wt% or less with respect to the content of the organic resin. can get.

DESCRIPTION OF SYMBOLS 1 Ceramic composite sheet 2 Metal foil 2a Uncoated part 2b Tab 3 Dielectric layer 4 Conductive layer 5-1 Positive electrode part 5-2 Negative electrode part 6 Metal foil 61 Capacitor element 63 Lead wire 64-1 Positive electrode Side external terminal 64-2 negative side external terminal 65 case 66 sealing resin 67 terminal board 68a external electrode 68b external electrode

Claims (7)

Metal foil,
A dielectric layer laminated on the metal foil and comprising an organic resin and a dielectric ceramic powder;
A conductive layer laminated on the dielectric layer;
Providing
A ceramic composite sheet characterized by The conductive layer includes a conductive material having a tabular particle shape,
The ceramic composite sheet according to claim 1. The conductive layer further includes a conductive material having a spherical particle shape;
The ceramic composite sheet according to claim 2. The dielectric ceramic powder content in the dielectric layer is:
70 wt% or more and 97.5 wt% or less with respect to the content of the organic resin,
The ceramic composite sheet according to any one of claims 1 to 3. The organic resin is a polyamideimide resin,
The dielectric ceramic powder is a barium titanate powder;
The ceramic composite sheet according to any one of claims 1 to 4, wherein: The conductive layer includes graphite having a flat particle shape and carbon black having a spherical particle shape;
The ceramic composite sheet according to claim 3. Comprising a plurality of ceramic composite sheets according to any one of claims 1 to 6,
Capacitor characterized by.

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