JPS6363728A - Highly dielectric resin - Google Patents

Abstract

PURPOSE:To obtain the title injection-moldable resin which has a high dielectric constant and can give a small high-performance capacitor, by kneading an injection-moldable resin with a specified ceramics dielectric member. CONSTITUTION:A highly dielectric resin 13 is obtained by kneading an injection- moldable resin 11 (e.g., a mixture of polybutylene terephthalate with a glass fiber) with at least one powdery or fibrous ceramics dielectric member 12 selected from among BaTiO3, BaSnO3, BaZrO3, CaZrO3, CaSnO3, SrTiO3, PbTiO3, La2O3.2TiO2, CeO2, CaTiO3, MgTiO3, Bi2(SnO3)3, Bi2(TiO3)3, NiSnO3, MgZrO3 and MgSnO3. A capacitor 20 is obtained by embedding electrodes 15 and 16 fitted with lead wires 17 and 18 in the resin 13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a high dielectric resin suitable for ceramic capacitors, filters, and the like.

(Prior art) Ceramic dielectric members are mainly used for capacitors, filters, etc. For example, barium titanate (BaTi)
In the case of Os), generally, as shown in Fig. 5, metal is plated or vapor-deposited on the facing surface (2), t3) of a ceramic element (1) made of a ceramic dielectric member formed into a plate shape. deposited with an electrode (4);
(5) is provided to form a capacitor. Such a capacitor is made into a product through a very large number of steps as shown in FIG. Briefly, titanium oxide powder and barium carbonate powder, which are raw materials, are mixed and ground, calcined and finely pulverized to produce a calcined raw material made of barium titanate, and a binder is added to this.

Additives are mixed, crushed, formed into a predetermined shape, and fired to create a ceramic element (1). Electrodes (4) (<5) are applied to both sides of this by coating and baking, and then After soldering the terminals (7) and C8), a resin coating is applied to complete the ceramic capacitor. Since this process involves a large number of steps, the cost is high, and there is a demand for simplification. On the other hand, as shown in Figure 6, the manufacturing process is greatly simplified for the type encapsulated with thermoplastic resin (9) by injection molding, but the dielectric strength of the resin itself is about 4. Therefore, the capacitance C is small. In order to solve this problem, the surface area must be increased or the electrode gap must be decreased, but increasing the surface area causes problems in terms of space. Furthermore, if the gap between the electrodes is made small, it becomes difficult for the resin (9) to be filled between them, and when used at a high withstand voltage, a narrow gap between the electrodes makes it easier for leaks to occur. If a more expensive method is used, there are disadvantages in that there are restrictions on miniaturization and performance improvement.

(Problems to be solved by the invention) As mentioned above, capacitors sealed with resin can be made smaller and
There was an inconvenience in that there were restrictions on sexual confinement.

The present invention has been made in order to eliminate the above-mentioned disadvantages, and aims to provide a high dielectric resin that simplifies the process by injection molding and allows the production of a compact capacitor with improved performance.

[Structure of the invention]

(Means for Solving the Problems) The present invention is a high dielectric resin in which a powdery or fibrous ceramic dielectric member is kneaded into an injection moldable resin.

(Function) By kneading the ceramic dielectric material into the base injection moldable resin, we have made the dielectric constant significantly higher than that of the resin alone, which increases the productivity of injection molding and also increases the dielectric constant. Since it is expensive, a small and high-performance capacitor can be obtained even if the gap between the electrodes is maintained so that resin can be filled.

(Example) Hereinafter, details of the present invention will be described by way of an example with reference to FIGS. 1, 2, and 3.

PBT with a weight ratio of polybutylene terephthalate and glass fiber of 70:30 as injection moldable resin I
GF30% was used. Ceramic dielectric member C
As Lz, barium titanate (BaTiO8) powder is used as PBTGF30% and barium titanate in volume ratio.
As an example of 90:10. 80 as a second example
:20. As a third example, three types of high dielectric resin Q3 were obtained as an example of the present invention by mixing at a ratio of 70:30. Using this high dielectric resin ← Q, we can create an encapsulated capacitor as shown in Figure 1, that is, electrodes (to) the high dielectric resin αj.
, αe, and conductive wires αη, C are enclosed in these electric fences αs, qe.
A capacitor field with 1υ attached to each was obtained.

The manufacturing process of this capacitor will be briefly described with reference to FIG. The left side of Fig. 2 shows the process for obtaining the ceramic dielectric member α powder described in the conventional example, that is, the powder (average particle size 1 μm) of titanate)ZIJium (BaTi03), which is exactly the same as the conventional example, so the explanation will not be given. Omitted. Next, as shown on the right side of Fig. 2, the powder of this ceramic dielectric member (13) is kneaded into the above-mentioned PBTGF 30% at fat α9. As mentioned above.

A capacitor 1j shown in FIG. 1 is obtained by injection molding using this kneaded high dielectric resin α3.

The dielectric constant ε of a mixture is generally calculated as follows.

toy g = X1Lay f, 4-X2Lay
g2・・・・・・・・・ (1) In formula (1), al, @,
is the dielectric constant of the component material, Xl is the volume fraction of the component material.

Now, as shown in FIG. 4, barium titanate has a dielectric constant ε of 2000 at room temperature and a high value of 10000 at 120° C., and the dielectric constant of PBTGF30 resin is 4 at room temperature. If the electrode area of the capacitor (a) shown in FIG. 1 is 5=lOd and the electrode gap d=1 cyN, the dielectric constant and capacitance at room temperature for each example are calculated as shown in Table 1.

Table 1 As shown in this table, the high dielectric resin of this example (13) was made of polybutylene terephthalate glass fiber 30.
The capacitance is larger than that of a single resin (Ll) consisting of

In the above embodiment, barium titanate (BaTiO,) was used as the ceramic dielectric member, but barium stannate (BaSnO,) may also be used.

Barium zirconate (BaZrOl), calcium zirconate (CaZrOs), calcium stannate (C
aSnO3), strontium titanate (S r T
103 ) + Lead titanate (pb'rio, ) * Titanate7a57Ta7 (La, O,,2TiO3), Cesium oxide (CeO2), Calcium titanate (CaT
iO3), magnesium titanate (MpTiO,)
, bismuth stannate<Bit (8nOi)s) + bix titanate (Bi, (Ti 03)3).

Nickel sulfate (NiSnO,), Magnesium zirconate (M7ZrO,), Tin powder (MP SnO3) You can select one or more types of suds and mix them in.Also, resin αυ as a paste. Any material that can be injection-molded, such as heat, thermosetting property, etc., may be used, and the ceramic 8-electroelectric member may be in the form of a fiber. Furthermore, although this embodiment has been described with reference to a capacitor, it is of course possible to apply the present invention to a filter.

〔Effect of the invention〕

As detailed above, the high dielectric resin of the present invention is made by kneading a ceramic dielectric member into an injection moldable resin, so the dielectric constant is uniform and injection molding is possible, so the manufacturing process is simple. This is extremely beneficial in reducing costs and improving productivity.

In addition, since the dielectric constant is higher than that of conventional resins, the area of one capacitor, t! Since both the electrode gap can be made small, a compact and high-performance capacitor can be obtained.

In addition, if the electrode gap is set sufficiently, a large withstand voltage and capacity can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a capacitor manufactured using each embodiment of the present invention, FIG. 2 is a chart showing the manufacturing process of a capacitor using each embodiment, and FIG. Figure 4 is a perspective view of a conventional capacitor, Figure 5 is a chart showing the capacitor manufacturing process, and Figure 6 is a longitudinal cross-section of the same capacitor. It is a diagram. I...Jiyuji, (L3...Ceramic dielectric member. αj...High dielectric resin. Agent Patent attorney Noriyuki Chika Yudo Kikuo Takehana Figure 2 da 11L (°Cn 3rd) Figure ■ Grounder Figure 6 Circle] Mouth 4 Figure Figure 5

Claims (2)

[Claims] (1) A high dielectric resin characterized by kneading a powdery or fibrous ceramic dielectric member into an injection moldable resin. (2) The ceramic dielectric member is barium titanate (B
aTiO_3), barium stannate (BaSnO_3),
Barium zirconate (BaZrO_3), calcium zirconate (CaZrO_3), calcium stannate (Ca
SnO_3), strontium titanate (SrTiO_
3), lead titanate (PbTiO_3), lanthanum titanate (La_2O_3・2TiO_2), cesium oxide (
CeO_2), calcium titanate (CaTiO_3)
, magnesium titanate (MgTiO_3), bismuth stannate (Bi_2(SnO_3)_3), bismuth titanate (Bi_2(TiO_3)_3), nickel stannate (NiSnO_3), magnesium zirconate (MgZ
The high dielectric resin according to claim 1, characterized in that the resin is made of one or more of the following: rO_3) and magnesium stannate (MgSnO_3).