JP7371613B2 - Encapsulated body for electronic components - Google Patents

Description

The present invention relates to a resin composition for insert molding and a sealed body for electronic components.

2. Description of the Related Art In recent years, electronic devices such as personal computers and mobile phones use electronic component mounting boards in which electronic components such as semiconductor elements, capacitors, and coils are attached to the substrate. Since such electronic components may be adversely affected by external environmental factors such as water, humidity, and dust, electronic components have been sealed with resin to protect them from external environmental factors. Furthermore, in order to protect electronic components from the adverse effects of electromagnetic waves, electromagnetic shielding properties are sometimes imparted to the sealing material.

For example, Patent Document 1 describes a method for sealing an electronic component mounting board that includes a substrate and an electronic component mounted on one side of the substrate, and includes an insulating layer and an electronic component mounted on one side of the insulating layer. A sealing film is disclosed that includes an electromagnetic wave shielding layer laminated on a wafer and an electromagnetic shielding layer.

JP 2019-21757 Publication

In the electronic component mounting board sealed with the sealing film of Patent Document 1, the electromagnetic shielding layer is formed on the surface side of the sealing part, and there is a risk that the electromagnetic shielding layer will deteriorate due to contact with external environmental factors. there were. The present invention has been made with attention to the above-mentioned problems, and its purpose is to obtain a sealed body for electronic components whose electromagnetic shielding layer has excellent durability against external environmental factors, and to obtain the electromagnetic shielding layer thereof. An object of the present invention is to provide a resin composition.

The resin composition for insert molding and the sealed body for electronic components according to the present invention, which can solve the above problems, have the following configuration.
[1] A resin composition for insert molding containing a resin and an electromagnetic shielding filler.
[2] It has an electronic component, and the electronic component is sealed with a resin molding containing an electromagnetic shielding layer formed directly on the surface of the electronic component using the resin composition for insert molding according to [1] above. In the cross section of the resin molded article in the direction perpendicular to the surface of the electronic component, the number A of the electromagnetic shielding fillers per 200 μm square in the area closer to the surface of the electronic component (number/40 ,000 μm ² ) is larger than the number B (numbers/40,000 μm ² ) of the electromagnetic shielding filler per 200 μm square in the region near the surface of the resin molded article. .
[3] The electronic component sealed body according to [2] above, wherein the resin is at least one selected from the group consisting of thermoplastic resins and thermosetting resins.
[4] The electronic component sealed body according to [2] or [3] above, wherein the electromagnetic shielding filler is a conductive filler.
[5] The electronic component encapsulation according to any one of [2] to [4] above, wherein the electromagnetic shielding filler has an aspect ratio of 1.5 or more.
[6] The electronic component according to [3] above, wherein the thermoplastic resin is at least one selected from the group consisting of polyester resin, polyamide resin, polyolefin resin, polycarbonate resin, and polyurethane resin. sealed body.
[7] The thermosetting resin is at least one selected from the group consisting of epoxy resins, phenolic resins, unsaturated polyester resins, diallyl phthalate resins, urethane (meth)acrylate resins, and polyimide resins. The sealed body of the electronic component according to the above [3], which is a seed.

According to the present invention, with the above configuration, it is possible to provide a sealed body for an electronic component whose electromagnetic shielding layer has excellent durability against external environmental factors, and a resin composition for obtaining the electromagnetic shielding layer.

FIG. 1 is a sectional view of a sealed body of an electronic component according to a first embodiment. FIG. 2 is a sectional view of a sealed electronic component according to a second embodiment. FIG. 3 is a cross-sectional view of a sealed body of an electronic component according to a third embodiment. FIG. 4 is a sectional view of a sealed electronic component according to a fourth embodiment.

In the following, the present invention will be explained in more detail based on the following embodiments, but the present invention is not limited by the following embodiments, and may be modified as appropriate within the scope that fits the spirit of the above and below. Of course, it is also possible to implement in addition, and all of them are included in the technical scope of the present invention. In addition, in each drawing, member numbers etc. may be omitted for convenience, but in such a case, the specification and other drawings shall be referred to. Further, the dimensions of various members in the drawings are given priority to help understanding the features of the present invention, and therefore may differ from actual dimensions.

The electronic component encapsulation of the present invention is a resin molded product in which the electronic component includes an electromagnetic shielding layer formed directly on the surface of the electronic component using an insert molding resin composition containing a resin and an electromagnetic shielding filler. In the cross section of the resin molded product in the direction perpendicular to the surface of the electronic component, the area close to the surface of the electronic component (hereinafter sometimes referred to as the internal area) has an electromagnetic shield of 200 μm square. Number of sexual fillers A (pieces/40,00
0 μm ² ) is the number B of electromagnetic shielding fillers per 200 μm square in the region closer to the surface of the resin molded product (hereinafter sometimes referred to as the external region) (pieces/40,000 μm).
m ² ). As a result of intensive studies by the present inventors, it has been found that in the electromagnetic shielding layer, it is the electromagnetic shielding filler in the external region that is likely to deteriorate due to the influence of external environmental factors. Therefore, it has been found that deterioration of the electromagnetic shielding layer due to external environmental factors can be easily prevented by making the number density of the electromagnetic shielding filler smaller in the outer region than in the inner region of the resin molding.

Furthermore, in the electronic component encapsulation of the present invention, an electromagnetic shielding layer is formed directly on the surface of the electronic component using a resin composition for insert molding. That is, by omitting the insulating layer between the electronic component and the electromagnetic shield layer as disclosed in Patent Document 1, the thickness and weight of the sealing portion can be easily reduced. As a result, for example, in the encapsulation of electronic components where there are many demands for the encapsulation to be lighter and more compact, a protective layer such as an electromagnetic shielding layer is provided on the outside to the extent that the thickness or weight of the encapsulation does not increase too much. be able to.

Below, with reference to FIGS. 1 to 4, sealed bodies for electronic components according to first to fourth embodiments of the present invention will be described. Note that the same reference numerals in each figure indicate the same elements, and the description thereof will be omitted as appropriate.

FIG. 1 is a cross-sectional view of a sealed body for an electronic component according to a first embodiment in a direction perpendicular to the surface of the electronic component.

As shown in FIG. 1, a sealed electronic component 10 includes an electronic component 1. As shown in FIG. The electronic component 1 is mounted on a substrate 3, and an electromagnetic shielding layer 2a is formed directly on the surface of the electronic component 1. Furthermore, a protective layer 2b is formed on the surface of the electromagnetic shield layer 2a. In this way, the electronic component 1 is sealed with the resin molding 2 including the electromagnetic shielding layer 2a and the protective layer 2b. Note that the electronic component 1 does not need to be mounted on the substrate 3 like the sealed electronic component according to the fourth embodiment described later.

Examples of the electronic component 1 include semiconductor elements such as transistors, capacitors, coils, resistors, and the like. When the conductive portion, semiconductor portion, etc. of the electronic component 1 are packaged with resin or metal, the surface of the electronic component 1 corresponds to the surface of the package.

The electromagnetic shielding layer 2a is located in a region (internal region) of the resin molded product 2 closer to the surface of the electronic component 1, and is made of a resin composition for insert molding containing a resin and an electromagnetic shielding filler. It is formed. It can also be said that the internal region is a region located closer to the surface of the electronic component 1 than a virtual plane located between the surface of the electronic component 1 and the surface of the resin molded product 2.

The protective layer 2b is located in a region (external region) of the resin molded product 2 closer to the surface of the resin molded product 2, and is made of a resin composition for insert molding containing a resin and an electromagnetic wave shielding filler. It is formed. It can also be said that the external region is a region located closer to the surface of the resin molded product 2 than a virtual plane located between the surface of the electronic component 1 and the surface of the resin molded product 2. Further, the content of the electromagnetic shielding filler in the protective layer 2b is smaller than the content of the electromagnetic shielding filler in the electromagnetic shielding layer 2a.

In other words, the number A (pieces/40,000 μm ² ) of electromagnetic shielding fillers per 200 μm square in the internal region is larger than the number B (pieces/40,000 μm ² ) of electromagnetic shielding fillers per 200 μm square in the external region. The number is increasing. Thereby, the electromagnetic wave shield layer 2a can shield electromagnetic waves, and the protective layer 2b can protect the electromagnetic wave shield layer 2a from external environmental factors. Furthermore, the electromagnetic shielding properties of the resin molded product 2 can also be improved by containing an electromagnetic shielding filler in the protective layer 2b as well. Specifically, the number A (pieces/40,000 μm ² ) is preferably 1.01 times or more, more preferably 1.03 times or more, the number B (pieces/40,000 μm ² ). , more preferably 1.05 times or more, particularly preferably 1.1 times or more. On the other hand, the number A (pieces/40,000 μm ² ) is preferably 10 times or less the number B (pieces/40,000 μm ² ). This makes it easier to reduce distortions caused by thermal expansion, for example. Therefore, the number A (numbers/40,000 μm ² ) is more preferably 5 times or less, and even more preferably 2 times or less, than the number B (numbers/40,000 μm ² ). Note that the protective layer 2b does not need to contain an electromagnetic shielding filler. The number of electromagnetic shielding fillers can be measured by a known method using an electron microscope or the like. Furthermore, when counting the number of electromagnetic shielding fillers, fillers with a major axis of less than 0.5 μm are not counted because their electromagnetic shielding properties are weak.

The total area A (μm 2 ) of the electromagnetic shielding filler per 200 μm square (40,000 μm ² ) in the internal region is equal to the total area A (μm ² ) of the electromagnetic shielding filler per 200 μm square (40,000 μm ² ) in the external region.
It is preferable that the area is larger than the total area B (μm ² ) of the electromagnetic shielding filler. By making the total area of the electromagnetic shielding filler in the external region smaller than that in the internal region of the resin molding, deterioration of the electromagnetic shielding layer due to external environmental factors can be easily prevented.

The total area A (μm ² ) is preferably 1.01 times or more, more preferably 1.03 times or more, and still more preferably 1.05 times or more the total area B (μm ² ). Preferably, it is particularly preferably 1.1 times or more. On the other hand, the total area A (μm ² ) is preferably 10 times or less the total area B (μm ² ). This makes it easier to reduce distortions caused by thermal expansion, for example. Therefore, the total area A (μm ² ) is more preferably 5 times or less, and even more preferably 2 times or less, the total area B (μm ² ).

The 200 μm square region in the internal region is preferably selected from within 1.0 mm from the surface of electronic component 1, and more preferably selected from within 500 μm. On the other hand, the 200 μm square region in the external region is preferably selected from within 1.0 mm from the surface of the resin molded product 2, and more preferably selected from within 500 μm.

The 200 μm square area in the internal area is selected from within 10% of the surface of the electronic component 1 with respect to the height of the cross section of the resin molded product 2 in the direction perpendicular to the surface of the electronic component 1. is preferable, and more preferably selected from within a range of 5%. On the other hand, the 200 μm square area in the external area is preferably selected from an area within 10% of the surface of the resin molded article 2, and preferably selected from an area within 5%.

The electromagnetic shielding filler included in the electromagnetic shielding layer 2a is a material that can exhibit electromagnetic shielding properties by reflecting and absorbing electromagnetic waves.

The electromagnetic shielding filler is preferably a conductive filler. When the conductive filler has conductivity, it is possible to easily increase reflection loss of electromagnetic waves and increase absorption loss of electromagnetic waves.

The electromagnetic shielding filler preferably has a volume resistivity of 1 Ω·cm or less. This makes it easier to conduct electricity, and the lower the volume resistivity, the easier it is to exhibit electromagnetic shielding properties. Therefore, the volume resistivity is more preferably at most 10 ^-3 Ω·cm, more preferably at most 10 ^-5 Ω·cm, even more preferably at most 10 ^-6 Ω·cm, and even more preferably at most 10 -6 Ω·cm. ^-7 Ω·cm or less is particularly preferable.

Examples of the electromagnetic shielding filler include metal fillers, metal compound fillers, and carbon fillers. Further, as the electromagnetic wave shielding filler, a magnetic filler having conductivity, a metal plated body in which glass beads, fibers, etc. are coated with metal or the like may be used. Further, metal fillers, metal compound fillers, carbon fillers, magnetic fillers, glass beads, fibers, etc. coated with silica or the like may be used. These may be used alone or in combination of two or more.

Examples of metal fillers include aluminum, zinc, iron, silver, copper, nickel, stainless steel, palladium, and the like. These may be used alone or in combination of two or more.

Examples of metal compound fillers include zinc oxide, barium sulfate, aluminum borate, titanium oxide, titanium black, tin oxide, indium oxide, potassium titanate, and lead zirconate titanate. . These may be used alone or in combination of two or more.

Examples of carbon-based fillers include acetylene black, Ketjen black, furnace black, carbon black, carbon fiber, carbon nanotubes, carbon microcoils, and the like. These may be used alone or in combination of two or more.

The magnetic filler is capable of becoming magnetic and can absorb and reduce electromagnetic waves. Examples of magnetic fillers include ferrite fillers such as Mn ferrite, Ni ferrite, Zn ferrite, Ba ferrite, Sr ferrite, Mn-Zn ferrite, and Ni-Zn ferrite; silicon-containing fillers such as iron-aluminum-silicon alloys; Iron-based filler; Nickel-iron alloy filler such as nickel-manganese-iron alloy, nickel-molybdenum-copper-iron alloy, nickel-molybdenum-manganese-iron alloy; Iron-cobalt alloy filler; Neodymium-iron Examples include boron alloy fillers. Among these, ferromagnetic materials exhibiting ferromagnetism or ferrimagnetism are preferred.

Other examples of electromagnetic shielding fillers include magnetic fillers that do not have electrical conductivity.

The shape of the electromagnetic shielding filler is not particularly limited, but at least one type selected from the group consisting of spherical fillers, needle-shaped fillers, rod-shaped fillers, fibrous fillers, flat fillers, scale-shaped fillers, and plate-shaped fillers is preferable. . Among these, at least one type selected from the group consisting of needle fillers, rod fillers, fibrous fillers, flat fillers, scale fillers, and plate fillers is more preferable because it tends to improve conductivity. Furthermore, when a spherical filler is used, uneven distribution of stress concentration can be reduced, and distortion during thermal expansion can also be easily reduced. Therefore, the combination of a spherical filler and at least one selected from the group consisting of needle-shaped fillers, rod-shaped fillers, fibrous fillers, flat fillers, scale-shaped fillers, and plate-shaped fillers has not only good electromagnetic shielding properties but also Effective when heat resistance etc. are required.

The electromagnetic shielding filler preferably has an aspect ratio of 1.5 or more. When the aspect ratio of the electromagnetic shielding filler is 1.5 or more, the electromagnetic shielding property is easily improved. Therefore, the aspect ratio of the electromagnetic shielding filler is more preferably 3 or more, still more preferably 5 or more, and even more preferably 10 or more. On the other hand, when the aspect ratio is 60 or less, uneven distribution of stress concentration and distortion during thermal expansion are easily reduced. Therefore, the aspect ratio is preferably 60 or less, more preferably 40 or less, and even more preferably 30 or less.

The electromagnetic shielding layer 2a may include an electromagnetic shielding filler having an aspect ratio of 1.5 or more and an electromagnetic shielding filler having an aspect ratio of less than 1.5. In this case, the ratio of the number of electromagnetic wave shielding fillers having an aspect ratio of 1.5 or more to the electromagnetic wave shielding fillers having an aspect ratio of less than 1.5 is preferably 10% or more and 90% or less. When the number ratio is 10% or more, the conductivity is easily improved. Therefore, it is more preferably 30% or more, and still more preferably 40% or more. On the other hand, when the number ratio is 90% or less, uneven distribution of stress concentration and distortion during thermal expansion are easily reduced. Therefore, it is more preferably 70% or less, still more preferably 60% or less.

The electromagnetic shielding filler preferably has a major axis of 0.5 μm or more. When the major axis is 0.5 μm or more, electromagnetic shielding properties are easily improved. Therefore, the long axis of the electromagnetic shielding filler is more preferably 1.0 μm or more, still more preferably 2.0 μm or more, and still more preferably 5.0 μm or more. On the other hand, the upper limit of the major axis of the electromagnetic wave shielding filler is not particularly limited, but may be, for example, 500 μm or less, 300 μm or less, 100 μm or less, 50 μm or less, It may be 30 μm or less.

The electromagnetic shielding layer 2a may include an electromagnetic shielding filler having a major axis of 0.5 μm or more and an electromagnetic shielding filler having a major axis of less than 0.5 μm. In this case, the ratio of the number of electromagnetic shielding fillers having a major axis of 0.5 μm or more to the electromagnetic shielding fillers having a major axis of less than 0.5 μm is preferably 10% or more and 90% or less. When the number ratio is 10% or more, the conductivity is easily improved. Therefore, it is more preferably 30% or more, and still more preferably 40% or more. On the other hand, when the number ratio is 90% or less, uneven distribution of stress concentration and distortion during thermal expansion are easily reduced. Therefore, it is more preferably 70% or less, still more preferably 60% or less.

In the electromagnetic shielding layer 2a, the content of the electromagnetic shielding filler is preferably 3 parts by mass or more and 1000 parts by mass or less based on 100 parts by mass of the resin. When the proportion of the electromagnetic shielding filler is 3 parts by mass or more, the electromagnetic shielding property is easily improved. Therefore, the amount is more preferably 5 parts by mass or more, still more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more. On the other hand, when the proportion of the electromagnetic shielding filler is 1000 parts by mass or less, the adhesiveness of the electromagnetic shielding layer 2a is easily improved. Therefore, it is more preferably 800 parts by mass or less, still more preferably 300 parts by mass or less, even more preferably 100 parts by mass or less.

For the resin contained in the electromagnetic shielding layer 2a, refer to the description of the resin contained in the resin composition for insert molding of the present invention, which will be described later.

For the material, shape, aspect ratio, major axis, etc. of the electromagnetic shielding filler included in the protective layer 2b, reference can be made to the electromagnetic shielding filler included in the electromagnetic shielding layer 2a.

In the protective layer 2b, the content of the electromagnetic shielding filler is preferably 1 part by mass or more and 950 parts by mass or less based on 100 parts by mass of the resin. When the proportion of the electromagnetic shielding filler is 1 part by mass or more, the electromagnetic shielding properties of the protective layer 2b are easily improved. Therefore, it is more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, even more preferably 10 parts by mass or more. On the other hand, when the proportion of the electromagnetic shielding filler is 950 parts by mass or less, the adhesiveness of the protective layer 2b is easily improved. Therefore, it is more preferably 750 parts by mass or less, still more preferably 250 parts by mass or less, even more preferably 90 parts by mass or less. Note that the protective layer 2b does not need to contain an electromagnetic wave shielding filler.

For the resin contained in the protective layer 2b, refer to the resin described in the description section of the resin composition for insert molding of the present invention, which will be described later. Note that it is preferable that the resin is the same as the resin contained in the electromagnetic shielding layer 2a.

The outer shape of the resin molded article 2 is not particularly limited, and a concave portion or a convex portion may be provided as necessary. The number of electromagnetic shielding layers 2a in the resin molded product 2 is not limited to one layer, but may be two or more layers. Further, the protective layer 2b in the resin molded product 2 is not limited to one layer, but may be two or more layers.

The electronic component 1 can be sealed with the resin molded product 2 by, for example, the following method. First, the electromagnetic shielding layer 2a is formed on the electronic component 1 attached to the substrate 3 by insert molding using a molding resin composition containing a resin and an electromagnetic shielding filler. Furthermore, the protective layer 2b is formed by insert molding using a molding resin composition with a low content of electromagnetic shielding filler. In this way, the electronic component 1 can be sealed with the resin molded product 2.

Examples of the substrate 3 include a resin substrate, a glass epoxy substrate, a tin-plated copper substrate, a nickel-plated copper substrate, an SUS substrate, and an aluminum substrate. The resin substrate is preferably a substrate made of insulating resin.

Next, with reference to FIG. 2, a sealed body for an electronic component according to a second embodiment of the present invention will be described. FIG. 2 is a cross-sectional view of a sealed body for an electronic component according to a second embodiment in a direction perpendicular to the surface of the electronic component.

As shown in FIG. 2, the electronic component 1 in the electronic component sealed body 20 has an electromagnetic shielding layer 2a formed directly on the surface of the electronic component 1. As shown in FIG. Further, a protective layer 2b is provided on the surface of the electromagnetic shielding layer 2a on the side opposite to the mounting portion 4 of the electronic component 1 (hereinafter sometimes referred to as the upper surface). In this way, the protective layer 2b may be formed on a part of the surface of the electromagnetic shielding layer 2a. Since the upper surface of the electromagnetic shielding layer 2a is particularly susceptible to external environmental factors, it is preferable that at least the upper surface of the electromagnetic shielding layer 2a is protected by the protective layer 2b.

Next, with reference to FIG. 3, a sealed body for an electronic component according to a third embodiment of the present invention will be described. FIG. 3 is a cross-sectional view of a sealed body for an electronic component according to a third embodiment in a direction perpendicular to the surface of the electronic component.

As shown in FIG. 3, the electronic component 1 in the electronic component sealing body 30 has an electromagnetic shielding layer 2a formed directly on the surface of the electronic component 1.

In the electromagnetic shielding layer 2a, a region (internal region) located closer to the surface of the electronic component 1 than a virtual plane located between the surface of the electronic component 1 and the surface of the resin molded product 2 (electromagnetic shielding layer 2a). The content of the electromagnetic shielding filler is larger in the outer region located closer to the surface of the resin molded article 2 (electromagnetic shielding layer 2a) than the virtual surface. Specifically, a concentration gradient structure is formed in the electromagnetic shielding layer 2a such that the content of the electromagnetic shielding filler increases toward the inside. As a result, the electromagnetic shielding property is high on the inside of the electromagnetic shielding layer 2a, and the content of the electromagnetic shielding filler is small on the outside of the electromagnetic shielding layer 2a, making it easier to prevent deterioration due to contact with external environmental factors.

The concentration gradient structure can be formed, for example, in insert molding by allowing the material to stand in a plasticized state (molten state) for a long time in an injection molding machine, and then injection molding in that state. The above-mentioned standing time is, for example, 5 hours or more.

Next, with reference to FIG. 4, a sealed body for an electronic component according to a fourth embodiment of the present invention will be described. FIG. 4 is a cross-sectional view of a sealed body for an electronic component according to a fourth embodiment in a direction perpendicular to the surface of the electronic component.

As shown in FIG. 4, the electronic component 1 in the electronic component sealing body 40 has an electromagnetic shielding layer 2a formed directly on the surface of the electronic component 1. As shown in FIG. Furthermore, a protective layer 2b is formed on the surface of the electromagnetic shield layer 2a. In this way, the electronic component 1 is sealed with the resin molding 2 including the electromagnetic shielding layer 2a and the protective layer 2b. Like the electronic component sealing body 40, the electronic component 1 does not need to be mounted on a substrate.

The present invention also includes a resin composition for obtaining an electromagnetic shielding layer for a sealed body of these electronic components. Specifically, the resin composition of the present invention is a resin composition for insert molding containing a resin and an electromagnetic wave shielding filler.

As the electromagnetic wave shielding filler contained in the resin composition for insert molding, reference can be made to the electromagnetic wave shielding filler contained in the electromagnetic wave shielding layer 2a of the sealed body of the electronic component according to the first embodiment.

The resin contained in the resin composition for insert molding is preferably at least one selected from the group consisting of thermoplastic resins and thermosetting resins.

The thermoplastic resin is preferably at least one selected from the group consisting of polyester resins, polyamide resins, polyolefin resins, polycarbonate resins, and polyurethane resins. Among these, polyester resins are more preferred.

Examples of the polyester resin include those formed by reacting a carboxylic acid component and a hydroxyl group component. As carboxylic acid components, terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1, Examples include 2-cyclohexanedicarboxylic acid, dimer acid, hydrogenated dimer acid, naphthalene dicarboxylic acid, and the like. As a hydroxyl group component, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2-methyl-1,3- Propanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, dipropylene glycol, diethylene glycol, neopentyl glycol, 2,2,4-trimethyl-1,3- Pentanediol, tricyclodecane dimethanol, neopentyl glycol hydroxypivalate, 1,9-nonanediol, 2-methyloctanediol, 1,10-dodecanediol, 2-butyl-2-ethyl-1,3-propane Examples include diol, polytetramethylene glycol, polyoxymethylene glycol, cyclohexanedimethanol, and the like. These may be used alone or in combination of two or more. Commercially available products include, for example, crystalline polyester resins GM-950, GM-955, and GM-960 manufactured by Toyobo Co., Ltd.

As the polyester resin, polyester containing a polyalkylene glycol component is preferred. Specifically, a hard segment mainly containing a polyester segment and a soft segment mainly containing a polyalkylene glycol component are preferably ester bonded.

The hard segment is preferably contained in an amount of 20% by weight or more and 80% by weight or less, more preferably 30% by weight or more and 70% by weight or less, based on the entire polyester resin.

The main component of the polyester segment in the hard segment is preferably a polyester formed by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol and/or an alicyclic glycol. The main component means that it is contained in the polyester segment in an amount of 80% by weight or more, more preferably 90% by weight or more.

Aromatic dicarboxylic acids having 8 to 14 carbon atoms are preferred because they can improve heat resistance, and terephthalic acid and/or naphthalene dicarboxylic acids are more preferred because they easily react with glycol.

The aliphatic glycol and/or alicyclic glycol is preferably an alkylene glycol having 2 to 10 carbon atoms, more preferably an alkylene glycol having 2 to 8 carbon atoms. The aliphatic glycol and/or alicyclic glycol is preferably contained in an amount of 50 mol% or more, more preferably 70 mol% or more of the total glycol components. As the glycol component, ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, etc. are preferable, and 1,4-butanediol, 1,4 - Cyclohexane dimethanol is more preferred because it tends to improve the heat resistance of polyester.

The soft segment is preferably contained in an amount of 20% by weight or more and 80% by weight or less, more preferably 30% by weight or more and 70% by weight or less, based on the entire polyester resin.

The polyalkylene glycol component in the soft segment is preferably polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, etc., and polytetramethylene glycol is more preferable in terms of improving flexibility and reducing melt viscosity. .

It is preferable that the soft segment mainly consists of a polyalkylene glycol component. The copolymerization ratio of the soft segment is preferably 1 mol% or more, more preferably 5 mol% or more, and 10 mol% or more when the entire glycol component constituting the polyester resin is 100 mol%. It is more preferable that the amount is 20 mol% or more, and particularly preferably 20 mol% or more. This increases the melt viscosity, making it easier to seal at low pressure. On the other hand, it is preferably 90 mol% or less, more preferably 55 mol% or less, even more preferably 50 mol% or less, and particularly preferably 45 mol% or less. This makes it easier to improve heat resistance.

The number average molecular weight of the soft segment is preferably 400 or more, more preferably 800 or more. This makes it easier to impart flexibility. On the other hand, the number average molecular weight of the soft segment is preferably 5,000 or less, more preferably 3,000 or less. This can facilitate copolymerization with other copolymerization components.

The number average molecular weight of the polyester resin is preferably 3,000 or more, more preferably 5,000 or more, still more preferably 7,000 or more. Thereby, the hydrolysis resistance of the resin composition and the strength and elongation under high temperature and high humidity can be easily improved. On the other hand, the upper limit is preferably 60,000 or less, more preferably 50,000 or less, even more preferably 40,000 or less. It becomes easier to reduce melt viscosity and molding pressure can be reduced.

The melting point of the polyester resin is preferably 70°C or higher and 210°C or lower, more preferably 100°C or higher and 190°C or lower.

Examples of the polyamide resin include resins having an amide bond in the molecule. Specifically, the polyamide resin is preferably a reaction product of dimer acid, aliphatic dicarboxylic acid, aliphatic, alicyclic and/or polyether diamine. Specifically, 50 to 98 mol% of dimer fatty acids, 2 to 50 mol% of C ₆ to C ₂₄ aliphatic dicarboxylic acids, 0 to 10 mol% of C ₁₄ to C ₂₂ monocarboxylic acids, and 0 to 40 mol%. More preferably, it contains polyether diamine and 60 to 100 mol% aliphatic diamine. Examples of commercially available products include THERMELT 866, 867, 869, and 858 manufactured by Bostick.

As polyolefin resins, monopolymers or copolymers of olefins such as ethylene, propylene, butene; copolymers of monomer components copolymerizable with these olefins; or maleic anhydride-modified products thereof etc. Specifically, polyolefin resins include polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methyl methacrylate copolymer, and ethylene-vinyl acetate copolymer. Examples include α-olefin copolymers, ethylene-propylene copolymers, ethylene-butene copolymers, propylene-butene copolymers, and the like. These may be used alone or in combination of two or more.

Examples of the polycarbonate resin include those obtained by the reaction of a polyfunctional hydroxy compound and a carbonate-forming compound. Examples of the polyfunctional hydroxy compound include 4,4'-dihydroxybiphenyls which may have a substituent, bis(hydroxyphenyl)alkanes which may have a substituent, and the like. Examples of the carbonate-forming compound include various carbonyl dihalides such as phosgene, haloformates such as chloroformate, and carbonate compounds such as bisaryl carbonate.

Examples of polyurethane resins include those formed by reacting a hydroxyl component (prepolymer) with an isocyanate compound (curing agent). Examples of the hydroxyl group component include at least one selected from the group consisting of polyester polyols, polycaprolactone polyols, polyether polyols, and polyalkylene polyols. The isocyanate compound includes at least one diisocyanate selected from the group consisting of trimethylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), and xylylene diisocyanate (XDI). Can be mentioned.

The thermosetting resin is at least one selected from the group consisting of epoxy resins, phenolic resins, unsaturated polyester resins, diallyl phthalate resins, urethane (meth)acrylate resins, and polyimide resins. is preferred. Among these, urethane (meth)acrylate resins or epoxy resins are more preferred.

Examples of epoxy resins include bisphenol-type epoxy resins made from bisphenol A, bisphenol F, bisphenol S, etc., or derivatives thereof, bixylenol-type epoxy resins made from bixylenol and its derivatives, and biphenol-type epoxy resins made from biphenol and its derivatives. Examples include epoxy resins such as naphthalene-type epoxy resins from naphthalene and its derivatives, and novolak-type epoxy resins. The epoxy equivalent, which is a guideline for the molecular weight of the epoxy resin, is preferably 174 to 16,000 g/eq. These may be used alone or in combination of two or more. Epoxy (meth)acrylate is preferred as the epoxy resin. Epoxy (meth)acrylate is obtained by adding acrylic acid or methacrylic acid to an epoxy resin having two or more glycidyl ether groups in one molecule. ) acrylates. Alternatively, it may be an epoxy (meth)acrylate resin in which epoxy (meth)acrylate is dissolved in a radically polymerizable monomer and/or a radically polymerizable polymer.

As the phenolic resin, various resins having phenol residue as a constituent unit can be used, such as phenol, cresol, xylenol, p-alkylphenol, chlorophenol, bisphenol A, phenol sulfonic acid, resorcin, various modified phenols, etc. Examples include resins formed by reacting phenols having a hydroxyl group with aldehydes such as formalin and furfural.

The unsaturated polyester resin is formed by reacting an acid component and an alcohol component. Examples of the acid component include unsaturated polybasic acids or their anhydrides such as maleic acid, fumaric acid, and itaconic acid, and aromatic carboxylic acids and their anhydrides such as phthalic acid, isophthalic acid, and terephthalic acid. Examples of the alcohol component include alkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol, and aromatic diols such as bisphenol A and bisphenol AC _2-4 alkylene oxide.

Examples of the diallyl phthalate resin include resins obtained from diallyl phthalate monomers such as diallyl phthalate, diallyl isophthalate, diallyl terephthalate, and diallyl orthophthalate.

The urethane (meth)acrylate resin is obtained, for example, by reacting a diisocyanate with at least one member selected from the group consisting of polyalcohols, polyester polyols, and polyether polyols having two or more hydroxyl groups in one molecule. It can be obtained by reacting the isocyanate at the molecular terminal of a compound and/or the isocyanate group of a compound having an isocyanate group in one molecule with a compound having an alcoholic hydroxyl group and a (meth)acrylate group. In addition, a compound having an alcoholic hydroxyl group and a (meth)acrylate group is reacted with a diisocyanate so that the isocyanate group remains, and the remaining isocyanate group is used to produce polyalcohols and polyester polyols having two or more hydroxyl groups in one molecule. A compound having a double bond of a (meth)acrylate group at the molecular end obtained by reacting with at least one selected from the group consisting of , and polyether polyol can be used as a urethane (meth)acrylate resin. .

Polyimide resin is a resin having an imide bond in its molecular main chain, and is, for example, a condensation polymer of aromatic diamine or aromatic diisocyanate and aromatic tetracarboxylic acid, or a condensation polymer of aromatic diamine or aromatic diisocyanate and bismaleimide. bismaleimide resin which is an addition polymer of aminobenzoic acid hydrazide and bismaleimide, and bismaleimide triazine resin which consists of a dicyanate compound and bismaleimide resin. One type is mentioned.

In addition to the resin and the electromagnetic wave shielding filler, the resin composition for insert molding can contain various additives commonly used in injection molding, etc., within a range that does not impair the characteristics of the resin molded product. Examples of additives include flame retardants, plasticizers, mold release agents, hydrolysis inhibitors, fillers, antioxidants, heat aging inhibitors, copper damage inhibitors, antistatic agents, light stabilizers, ultraviolet absorbers, etc. It will be done. These additives may be used alone or in combination of two or more.

1 Electronic component 2 Resin molding 2a Electromagnetic shielding layer 2b Protective layer 3 Substrate 4 Attachment portion 10 Encapsulated electronic component according to the first embodiment 20 Encapsulated electronic component according to the second embodiment 30 Third embodiment Encapsulated body of electronic component according to 40 Encapsulated body of electronic component according to fourth embodiment

Claims (6)

Contains electronic components,
The electronic component is sealed with a resin molding including an electromagnetic shielding layer formed on the surface of the electronic component using a resin composition for insert molding containing a resin and an electromagnetic shielding filler,
In the cross section of the resin molded article in the direction perpendicular to the surface of the electronic component, the number A (pieces/40,000 μm ² ) of the electromagnetic shielding filler per 200 μm square in the area closer to the surface of the electronic component is: , is 1.05 times or more the number B (pieces/40,000 μm ² ) of the electromagnetic shielding filler per 200 μm square in the region closer to the surface of the resin molded article ,
The surface of the electromagnetic wave shielding filler is not coated with an insulating material,
At least a portion of the electromagnetic wave shielding filler is a sealed body of an electronic component, in which at least a portion of the electromagnetic wave shielding filler is in contact with the electronic component. 2. The sealed electronic component according to claim 1, wherein the resin is at least one selected from the group consisting of thermoplastic resins and thermosetting resins. The sealed electronic component according to claim 1 or 2, wherein the electromagnetic shielding filler is a conductive filler. 4. The sealed electronic component according to claim 1, wherein the electromagnetic shielding filler has an aspect ratio of 1.5 or more. The electronic component sealed body according to claim 2, wherein the thermoplastic resin is at least one selected from the group consisting of polyester resin, polyamide resin, polyolefin resin, polycarbonate resin, and polyurethane resin. . The thermosetting resin is at least one selected from the group consisting of epoxy resins, phenolic resins, unsaturated polyester resins, diallyl phthalate resins, urethane (meth)acrylate resins, and polyimide resins. The electronic component sealed body according to claim 2.

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