JPH08109315A - Resin composition, and electronic part and piezoelectric ceramic part coated therewith - Google Patents

Abstract

PURPOSE: To obtain a resin composition capable of forming a double layer structure made up of upper layer with high mechanical strength and lower layer with flexibility, of maintaining the electrical properties and quality of the objects, and of improving the workability for such objects, thus useful for electronic parts, piezoelectric ceramic parts, etc., comprising a flexible base resin, hollow filler and curing agent. CONSTITUTION: This composition comprises (A) a flexible base resin (pref. containing a bisphenol F-type epoxy resin and a dimer acid-modified epoxy resin), (B) a hollow filler pref. made of glass, (C) a curing agent, and pref. (D) an additive consisting of a silicone-based defoaming agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition, an electronic component coated with the resin composition, and a piezoelectric ceramic component coated with the resin composition.

[0002]

2. Description of the Related Art Conventionally, electronic parts have been treated with various resins such as potting, casting or coating in order to maintain their functions. For example,
The ceramic filter is coated with exterior resin for the purpose of protecting the piezoelectric ceramic plate from the external environment.

However, in electronic components such as hybrid integrated circuits, ceramic filters, capacitors, etc., the residual stress of the resin has a great influence on the electrical and mechanical properties.
For example, the ceramic filter has the following problems.

(1) If the external resin is tightly tightened, stress is applied to the piezoelectric ceramic plate, and the electrical characteristics of the ceramic filter deteriorate, and in severe cases cracks occur in the piezoelectric ceramic plate.

(2) When the vibration generated in the piezoelectric ceramic plate propagates to the exterior resin, if the vibration cannot be absorbed by the exterior resin, the vibration is reflected by the piezoelectric ceramic plate and the electrical characteristics are deteriorated.

Therefore, when resin is used for electronic parts,
The flexibility of the resin is an important function, and the stress reduction of the resin is also important.

However, the greater the flexibility of the resin, the lower the mechanical strength and moisture resistance of the resin. For example, when a flexible resin is used as the exterior resin, the resin strength is low only with this resin, so that there is no effect of reinforcing the internal elements in strength, and moisture resistance reliability cannot be obtained.

As a method for solving these problems, JP-A-1-165195 and JP-A-60-2744 are used.
No. 0 and the like show a two-layer structure of resin. For example, a soft resin such as a silicone resin is first coated, and then a hard resin such as an epoxy resin is coated.

Further, the method for reducing the stress of the resin is, at present, a compound of a dimer acid-modified epoxy resin, a silicone resin, a urethane resin or an acrylonitrile butadiene copolymer to lower the elastic modulus, or to add a large amount of an inorganic filler. Methods such as blending to reduce the linear expansion coefficient have been performed.

[0010]

However, the conventional resin composition as described above has the following problems. (1) In the method of forming the resin into a two-layer structure, there is a problem such as adhesion and familiarity at the interface between the resins in a combination of different materials such as a silicone resin and an epoxy resin. Must. In addition, the use of two types of resin requires management, curing, casting, coating, etc. of the resin for each resin, which complicates the production process.

(2) In the method of reducing the stress of the resin,
In the former method of lowering the elastic modulus of the resin, the heat resistance of the resin,
Humidity resistance and mechanical strength are greatly reduced, which impairs reliability of electronic parts, and in the latter method of lowering the linear expansion coefficient, the resin is highly filled with an inorganic filler, resulting in high viscosity. Workability is significantly reduced.

Further, the electronic parts and ceramic filters coated with the conventional resin composition as described above have the following problems. (3) In the method of reducing the stress of the resin, when the resin composition obtained by lowering the elastic modulus of the former resin is used, the strength of the exterior resin is remarkably reduced, and the element such as the piezoelectric ceramic plate is subjected to a physical external force. Cannot be protected from.

(4) When the resin composition obtained by the latter method of lowering the linear expansion coefficient is used, since the ratio of the resin as the matrix is small and the exterior resin becomes porous,
In chip filters, etc., the plating solution is absorbed by the resin,
External electrodes cannot be plated. Also, the humidity resistance is low.

An object of the present invention is to provide a resin composition capable of easily forming a two-layer structure of a lower layer portion having flexibility and an upper layer portion having strength.

Further, the present invention has a resin composition having mechanical strength capable of withstanding a physical external force and capable of maintaining electrical characteristics and quality, and an electronic component coated with the resin composition. The purpose is to provide.

Further, the present invention protects the piezoelectric ceramic plate from physical external force and tightening of the exterior resin, and
An object of the present invention is to provide a piezoelectric ceramic component capable of absorbing reflection of vibration on the piezoelectric ceramic plate and ensuring plating of external electrodes.

[0017]

The resin composition of the present invention comprises:
It was made to solve the above problems,
It is characterized by containing a flexible base resin, a hollow filler, and a curing agent.

Further, the resin composition of the present invention is characterized in that the flexible base resin contains a bisphenol F type epoxy resin and a dimer acid-modified epoxy resin.

Further, the resin composition of the present invention is characterized in that the hollow filler is made of glass.

Further, the resin composition of the present invention is characterized by containing an additive comprising a silicone type defoaming agent.

The electronic component coated with the resin composition of the present invention includes an electronic component substrate, and an electronic resin provided so as to cover at least a part of the electronic component substrate. A component, wherein the exterior resin is composed of the resin composition according to any one of claims 1 to 4, and is composed of a lower layer portion composed of at least a base resin, and at least a hollow filler and a base resin. It is characterized in that it forms a layered structure with the upper layer portion.

Further, the piezoelectric ceramic component coated with the resin composition of the present invention includes a piezoelectric ceramic plate, a piezoelectric resonance electrode provided on an opposing plane of the piezoelectric ceramic plate, and an upper and lower surface so as to cover the piezoelectric ceramic plate. And an external electrode that is electrically connected to the piezoelectric resonance electrode. The exterior resin is made of the resin composition according to any one of claims 1 to 4, and at least a base. It is characterized in that a layered structure is formed of a lower layer portion made of a resin and an upper layer portion made of at least a hollow filler and a base resin.

[0023]

In the resin composition of the present invention, due to the difference in specific gravity between the base resin and the hollow filler, a flexible lower layer portion composed of at least the base resin with one type of resin composition,
It is possible to form a two-layer structure including at least a hollow filler and an upper layer portion having strength which is composed of a base resin.

When the base resin contains a bisphenol F type epoxy resin and a dimer acid-modified epoxy resin, both the bisphenol F type epoxy resin and the dimer acid modified epoxy resin have low viscosities. It is possible to prevent an increase in viscosity.

When the filler is made of glass,
Since glass has a low coefficient of linear expansion, the expansion of the upper layer portion containing glass can be reduced.

Further, when an additive made of a silicone type defoaming agent is included, the air entrapped when the base resin is cured can be removed.

In the electronic component coated with the resin composition of the present invention, the electronic component substrate is composed of at least a flexible lower layer portion made of a base resin, at least a hollow filler and a base resin. By covering with an exterior resin that forms a two-layer structure with an upper layer that has the following strength, the upper layer protects the electronic component substrate from physical external force, and the lower layer reduces the tightening by the exterior resin, and the electronic component It is possible to reduce the stress on the substrate.

Further, in the piezoelectric ceramic component coated with the resin composition of the present invention, the piezoelectric ceramic plate is protected from physical external force by the upper layer portion having strength, which is composed of at least the hollow filler and the base resin, Moreover, absorption of the plating solution can be prevented. Further, the flexible lower layer portion made of at least the base resin can reduce tightening by the exterior resin and can absorb unnecessary vibration of the piezoelectric ceramic plate.

[0029]

EXAMPLES Examples of the resin composition of the present invention, electronic parts coated with the resin composition, and piezoelectric ceramic parts coated with the resin composition will be described below. (Example 1) Table 1 shows the compositions of Examples 1-1 to 1-3 which are the resin compositions of the present invention. Example 1-1
Is 100 parts by weight of a bisphenol F type epoxy resin (epoxy equivalent 180) which is a base resin, and 100 parts by weight of a dimer acid-modified epoxy resin (epoxy equivalent 430) which is a base resin and a flexibility-imparting agent. The composition comprises 0.02 part by weight of a silicone-based defoaming agent which is an agent, 13 parts by weight of a hollow glass (specific gravity of 0.24) which is a filler, and 30 parts by weight of a modified aliphatic polyamine which is a curing agent.

In Example 1-2, 100 parts by weight of bisphenol F type epoxy resin, 100 parts by weight of dimer acid-modified epoxy resin, 0.02 part by weight of silicone defoamer, 26 parts by weight of hollow glass and modified 30 parts by weight of aliphatic polyamine.

In Examples 1-3, 100 parts by weight of bisphenol F type epoxy resin, 100 parts by weight of dimer acid-modified epoxy resin, 0.02 part by weight of silicone defoamer, 40 parts by weight of hollow glass, and modified 30 parts by weight of aliphatic polyamine.

For comparison, 100 parts by weight of bisphenol F type epoxy resin, 100 parts by weight of dimer acid-modified epoxy resin, 0.02 part by weight of silicone defoamer, and 30 parts by weight of modified aliphatic polyamine. Table 1 also shows Comparative Example 1-1 which is composed of the above and does not include the hollow glass as the filler.

[0033]

[Table 1]

A resin cured product is prepared using the resin composition of Example 1-1 to Comparative Example 1-1 described above. The resin cured product was produced by casting the resin in a mold having a depth of 4 mm and a length and width of 100 mm and heating at 150 ° C. for 1 hour.
This cured resin product was cut into a desired size to obtain a sample for physical property evaluation. A cross-sectional view of this resin cured product is shown in FIG.

In FIG. 1, 1 is an upper layer portion and 3 is a lower layer portion. Due to the difference in specific gravity between the resin and the hollow glass, the upper layer portion 1 contains the resin component and the hollow glass, and the lower layer portion 3 contains only the resin component.

Furthermore, Example 1-1 to Comparative Example 1-1
Table 2 shows the bending strength (MPa) and hardness (Shore D) characteristics of the resin cured product prepared from this resin cured product.

[0037]

[Table 2]

In Table 2, the hardness glass side is the upper layer portion of FIG. 1 and is formed of resin and hollow glass, and the hardness resin side is the lower layer portion of FIG. It is formed only of a resin not containing. Furthermore, the bending strength is measured according to JIS K6911.

From the results shown in Table 2, the resin cured products of Examples 1-1 to 1-3 using the resin composition of the present invention have a higher hardness while maintaining a lower hardness as compared with Comparative Example 1-1. It can be seen that it has bending strength.

By the way, although the bisphenol F type epoxy resin and the dimer acid-modified epoxy resin were used as the base resin in the above-mentioned examples, the present invention is not limited to this, and urethane resin other than epoxy resin, acrylic resin Alternatively, an ester resin, a silicone resin or the like may be used. Even if a solid resin is dissolved in a solvent to form a liquid, the present invention is not hindered.

Further, the modified aliphatic polyamine was used as the curing agent in the above-mentioned examples, but this is because it can be cured with a smaller addition amount than that of the acid anhydride curing agent. The curing agent is not particularly limited as long as it cures the main agent.

Further, although hollow glass having a specific gravity of 0.24 and an average particle size of 65 μm was used as the filler in the above-mentioned examples,
The specific gravity is smaller than the liquid resin of the present invention, and as long as it has a strength equal to or higher than the intended resin strength, it is not particularly limited to inorganic materials, organic materials, metallic materials, etc., but its specific gravity is hollow. Since the glass floats in the upper layer portion 1 of FIG. 1 and is completely contained, it is 5 relative to the specific gravity of the liquid resin.
0% or less is desirable.

(Example 2) Table 3 shows the composition of Example 2-1 which is the resin composition of the present invention. In Example 2-1, 50 parts by weight of bisphenol F type epoxy resin, 50 parts by weight of dimer acid-modified epoxy resin, 1 part by weight of surface treatment agent, 0.03 part by weight of silicone antifoaming agent, hollow glass ( Specific gravity: 0.24) is 13.3 parts by weight, and modified aliphatic polyamine is 29.7 parts by weight.

For comparison, 50 parts by weight of bisphenol F type epoxy resin, 50 parts by weight of dimer acid-modified epoxy resin, 1 part by weight of surface treatment agent, 0.03 parts by weight of silicone antifoaming agent, Silica (specific gravity: 2.2) is 1
Comparative Example 2-1 consisting of 22.9 parts by weight, modified aliphatic polyamine 29.7 parts by weight, bisphenol F type epoxy resin 50 parts by weight, dimer acid modified epoxy resin 5
Table 3 also shows 0 parts by weight, 1 part by weight of the surface treatment agent, 0.03 parts by weight of the silicone antifoaming agent and 29.7 parts by weight of the modified aliphatic polyamine. Comparative Example 2-1 does not contain hollow glass but contains silica.
Comparative Example 2-2 contains neither hollow glass nor silica.

[0045]

[Table 3]

The hollow glass compounded in Example 2-1 and the silica compounded in Comparative Example 2-1 have the same volume. Further, the surface treatment agents blended in Examples 2-1 to Comparative Example 2-2 are for improving the familiarity between the resin component and the hollow glass, and can improve the moisture resistance and the strength.

A resin cured product is prepared using the resin composition of Example 2-1 or Comparative Example 2-2 described above. The resin cured product was produced by casting the resin in a mold having a depth of 4 mm and a length and width of 100 mm and heating at 150 ° C. for 1 hour.
This cured resin product was cut into a desired size to obtain a sample for physical property evaluation.

Here, Example 2-1 to Comparative Example 2-2
Using this resin cured product prepared with the above composition, the flexural modulus was measured as the physical properties of the resin cured product, and the glass transition point and the linear expansion coefficient were measured as the thermal properties. Further, the heat shock resistance (H / S resistance) evaluated as a finished product was evaluated. These are shown in Table 4.

[0049]

[Table 4]

The heat shock resistance in Table 4 was evaluated by repeating a cooling / heating cycle of -55 [deg.] C./30 minutes and 85 [deg.] C./30 minutes 25 times, and cracking even one of 10 tests. When it occurred, it was judged as NG.

From the results shown in Table 4, in Example 2-1 using the resin composition of the present invention, the residual stress was higher than that of Comparative Examples 2-1 and 2-2 because the hollow glass was blended. It is possible to form an exterior resin having less heat shock resistance.

By the way, although the bisphenol F type epoxy resin and the dimer acid-modified epoxy resin were used as the base resin in the above-mentioned examples, the base resin is not particularly limited thereto, and urethane resin, acrylic resin, ester other than epoxy resin may be used. Resin, silicone resin or the like may be used. Also,
Even in the case of a solid resin, the present invention is not hindered if the hollow filler is kneaded without being damaged.

Further, although the modified aliphatic polyamine was used as the curing agent in the above examples, the present invention is not limited to this, and the curing agent is not particularly limited as long as it cures the main agent.

Further, although hollow glass was used as the filler in the above-mentioned examples, the material is not particularly limited as long as it is a hollow material, such as carbon, alumina, zirconia, phenol, vinylidene chloride, etc. You may mix and use.

The hollow filler is 5 v in the resin.
Although the effects of the invention can be obtained if the amount is blended in an amount of ol% or more, it is preferably in the range of 10 to 60 vol%. If the compounding amount of the hollow filler is less than 5 vol%, the residual stress cannot be sufficiently reduced, and if it is 80 vol% or more, the viscosity of the resin is greatly increased and the workability is significantly reduced.

(Example 3) Table 5 shows the composition of Example 3-1 which is the resin composition of the present invention. Example 3-1 is 100 parts by weight of bisphenol F type epoxy resin, 100 parts by weight of dimer acid-modified epoxy resin, 0.04 parts by weight of silicone antifoaming agent, 26 parts by weight of hollow glass, modified aliphatic polyamine. Is 30 parts by weight.

For comparison, 100 parts by weight of bisphenol F type epoxy resin, 100 parts by weight of dimer acid-modified epoxy resin, 0.04 part by weight of silicone-based defoaming agent, and 30 parts by weight of modified aliphatic polyamine. Comparative Example 3-1 consisting of is also shown in Table 5. Comparative Example 3-1 does not contain hollow glass.

[0058]

[Table 5]

Next, FIG. 2 shows a sectional view of a ceramic filter formed using the resin composition of Example 3-1. This ceramic filter has a piezoelectric ceramic plate 5 in the vicinity of the center of its cross section, and a piezoelectric resonance electrode 7 is provided on the opposing plane of the piezoelectric ceramic plate 5. A cavity 6 for a vibrating space is formed near the center of the piezoelectric ceramic plate 5, and the upper and lower portions of the piezoelectric ceramic plate 5 are made of the resin composition of Example 3-1 via the piezoelectric resonance electrode 7. It is covered with the exterior resin 8. An external electrode 9 electrically connected to the piezoelectric resonance electrode 7 is provided on at least one of the upper and lower surfaces formed by the piezoelectric ceramic plate 5 and the exterior resin 8 or the side surface.

The exterior resin 8 has a layered structure composed of an upper layer portion 1 and a lower layer portion 3. The upper layer portion 1 is the same as that in Example 3-
When the resin composition of No. 1 is heat-cured, the hollow glass having a smaller specific gravity than the resin floats and hardens, so that the resin composition and the hollow glass are contained. Further, the lower layer portion 3 contains only the resin component. The casting of the exterior resin 8 is performed by holding the element in the center of the mold frame and casting on each side.

Further, external electrodes 9 are provided on both ends of the piezoelectric ceramic plate 5. In FIG. 2, the external electrode 9
Is also provided in the center, and has the same structure on the left and right.

Furthermore, Example 3-1 and Comparative Example 3-1
Table 6 shows the evaluation of the electrical characteristics, the flexural strength, and the strength of the exterior resin of the ceramic filter formed by the above composition.

[0063]

[Table 6]

The flexural strength in Table 6 is 45 mm ×
Solder a ceramic filter to the center of 100 mm x 0.8 mm glass epoxy substrate, and the distance between fulcrums is 900 m
It was judged whether the glass epoxy substrate had a function as a filter when it was bent by 3 mm and flexed by applying a load from the back side on which the ceramic filter was mounted at a bending speed of 3 mm / min. The resin strength is a relative judgment between Example 3-1 and Comparative Example 3-1, and the electrical characteristics are a judgment when compared with the conventional one.

From the results of Table 6, it was found that the ceramic filter using the resin composition of Example 3-1 had better resin strength and flexural strength than Comparative Example 3-1.

By the way, although the ceramic filter has been described in the above embodiment, the present invention is not limited to this, and a piezoelectric ceramic component such as a ceramic resonator may be used.

(Example 4) Table 7 shows the compositions of Examples 4-1 and 4-2 which are the resin compositions of the present invention.
In Example 4-1, the bisphenol F type epoxy resin is 3
0 parts by weight, 70 parts by weight of dimer acid-modified epoxy resin,
Silicone defoamer 0.02 parts by weight, hollow glass 3
4 parts by weight and 22 parts by weight of modified aliphatic polyamine.

In Example 4-2, 30 parts by weight of bisphenol F type epoxy resin, 70 parts by weight of dimer acid-modified epoxy resin, 0.02 part by weight of silicone defoamer, 54 parts by weight of hollow glass and modified 20 parts by weight of aliphatic polyamine.

[0069]

[Table 7]

For comparison, 100 parts by weight of bisphenol A type epoxy resin, 78 parts by weight of phenol resin as a curing agent, 500 parts by weight of silica, 21 parts by weight of titanium oxide, and xylene as an organic solvent were used. Table 8 shows Comparative Example 4-1 consisting of 67 parts by weight.

[0071]

[Table 8]

Next, the resin compositions of Examples 4-1 to Comparative Examples 4-1 shown in Tables 7 and 8 were put into a planetary mixer and kneaded for 60 minutes to obtain exterior resins. However, since the hollow glass may be broken by the shearing force at the time of kneading, the hollow glass was kneaded for 60 minutes and then kneaded for 5 minutes.

The exterior resin obtained with the composition of Example 4-1 to Comparative example 4-1 was mounted on a ceramic filter, and the electrical characteristics were evaluated.

As a result, the hollow glass exhibits the same effect as the bubbles of the solvent type exterior resin as in Comparative Example 4-1, and Example 4-1 and Example 4-2 are the same as Comparative Example 4-1. The electrical characteristics similar to those of the solvent type exterior resin were obtained.

By the way, when a large amount of a filler such as silica is filled in the solvent type exterior resin as in Comparative Example 4-1, a large number of bubbles are relatively easily formed in the cured product. It In the piezoelectric ceramic component such as a ceramic filter, the air bubble has a function of absorbing unnecessary vibration of the piezoelectric ceramic plate, thereby improving the electrical characteristics of the piezoelectric ceramic component. In Example 4-1 and Example 4-2, it is possible to obtain the same effect as that of forming a large number of bubbles by filling the hollow resin, which is a hollow filler, in the exterior resin. The electrical characteristics of the piezoelectric ceramic component can be improved.

However, the exterior resin using an organic solvent as in Comparative Example 4-1, the viscosity is changed by volatilization of the organic solvent and the workability is not stable, and there is a danger in fire fighting or safety and hygiene. The hazard to the above workers is a problem. Furthermore, in recent years, it has been desired not to use an organic solvent for the exterior resin due to environmental problems, and thus it is effective to use Examples 4-1 and 4-2.

Here, in the above examples, hollow glass (made by Grace Japan Co., Ltd., trade name: FTD) is used as a filler.
However, the present invention is not limited to this, and commercially available carbon balloons, acrylic balloons and the like may be used. The compounding amount of the hollow filler is not particularly limited, but if the content is 5 vol% or less, the effect of the invention cannot be expected, and if it exceeds 85 vol%, the viscosity of the exterior resin becomes too high and the workability deteriorates. % ~ 6
0 vol% is desirable.

Also, in the above-mentioned examples, the cracking of the element was prevented by mixing the dimer acid-modified epoxy resin, which is a flexibility-imparting agent, as the base resin and lowering the elastic modulus. As described above, cracking of the element may be prevented by means of blending a large amount of filler such as silica.

Further, although the ceramic filter has been described in the above embodiments, the present invention is not limited to this, and a piezoelectric ceramic device such as a ceramic resonator may be used.

[0080]

INDUSTRIAL APPLICABILITY The resin composition of the present invention can be easily manufactured because one type of resin composition can form a two-layer structure of an upper layer portion having strength and a lower layer portion having flexibility. It is possible. Moreover, since the upper layer portion has strength,
Since the lower layer has flexibility while having mechanical strength capable of withstanding a physical external force, it is possible to maintain electrical characteristics and quality.

When the base resin contains a bisphenol F type epoxy resin and a dimer acid-modified epoxy resin, both the bisphenol F type epoxy resin and the dimer acid modified epoxy resin have low viscosities. Since it is possible to prevent an increase in viscosity, it is possible to improve workability.

When the filler is made of glass,
Since glass has a low coefficient of linear expansion, it is possible to reduce the expansion of the upper layer portion including the glass, and thus the stress to the lower layer portion can be reduced.

When the resin composition contains a silicone antifoaming agent, the air entrapped when the resin is cured can be removed, so that the resin composition can be formed more reliably. is there.

In the electronic component coated with the resin composition of the present invention, the electronic component substrate is covered with the resin composition forming the two-layer structure of the upper layer portion having strength and the lower layer portion having plasticity. As a result, the upper layer protects the electronic component substrate from physical external force, and the lower layer portion reduces the tightening by the exterior resin and weakens the stress on the electronic component substrate, thus increasing the mechanical strength against the physical external force. In addition, it is possible to maintain the electrical characteristics and quality.

Further, in the piezoelectric ceramic component coated with the resin composition of the present invention, the upper layer portion can protect the piezoelectric ceramic plate from physical external force and prevent absorption of the plating solution, so that the plating of the external electrode is prevented. It is possible to ensure. Further, since the lower layer portion can reduce tightening by the exterior resin and can absorb unnecessary vibration of the piezoelectric ceramic plate, it is possible to prevent the vibration from being reflected by the piezoelectric ceramic plate.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 1 Upper Layer Part 3 Lower Layer Part 5 Piezoelectric Ceramic Plate 6 Cavity Part 7 Piezoelectric Resonance Electrode 8 Exterior Resin 9 External Electrode

Claims (6)

[Claims] 1. A resin composition comprising a flexible base resin, a hollow filler, and a curing agent. 2. The resin composition according to claim 1, wherein the flexible base resin contains a bisphenol F type epoxy resin and a dimer acid-modified epoxy resin. 3. The resin composition according to claim 1 or 2, wherein the hollow filler is made of glass. 4. The resin composition according to claim 1, further comprising an additive comprising a silicone-based defoaming agent. 5. An electronic component comprising: an electronic component substrate; and an exterior resin provided so as to cover at least a part of the electronic component substrate, wherein the exterior resin comprises: 5. A layer structure comprising the resin composition according to claim 4 and having a lower layer portion made of at least a base resin and an upper layer portion made of at least a hollow filler and a base resin. And electronic components. 6. A piezoelectric ceramic plate, a piezoelectric resonance electrode provided on an opposing plane of the piezoelectric ceramic plate, an exterior resin provided above and below so as to cover the piezoelectric ceramic plate, and the piezoelectric resonance electrode are electrically connected to each other. An outer electrode is provided, and the exterior resin is made of the resin composition according to any one of claims 1 to 4, a lower layer portion made of at least a base resin, and at least a hollow filler and a base. A piezoelectric ceramic component having a layered structure including an upper layer portion made of a resin.