JP2000143872A - Composite resin material and casing for electronic equipment obtained therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite resin material light and excellent in thin-wall moldability and capable of giving a molded article with high rigidity and high impact resistance employing a variety of thermoplastic resins and to provide a casing for electronic equipment obtained therefrom. SOLUTION: In a composite resin material 1 of a structure wherein an inorganic filler 30, at least a part of whose outer surface is covered with elastomers 31 and 32, is dispersed in a thermoplastic resin 2, the elastomers 31 and 32 are caused to contain a first functional group compatible with the inorganic filler 30 and a second functional group compatible with the thermoplastic resin 2 or the same as that contained in the thermoplastic resin 2. Preferably, the elastomers 31 and 32 are composed of a first elastomer 31 containing the first functional group and covering at least a part of the outer surface of the inorganic filler 30 and a second elastomer 32 containing the second functional group and covering at least a part of the outer surface of the first elastomer 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite resin material having a structure in which an inorganic filler is dispersed in a thermoplastic resin, and a housing for electronic devices such as a notebook personal computer and a mobile phone obtained by using the same. is there.

[0002]

2. Description of the Related Art Conventionally, polycarbonate (PC) resins and acrylonitrile-butadiene-styrene copolymers (A) have been used as molding materials for electronic equipment housings and the like.
BS) resin is used. These resins easily undergo plastic deformation when a shocking load is applied and absorb impact energy, so that the electronic device housing is less likely to break. However, with the spread of portable electronic devices in recent years, molding materials for electronic device housings have been required to excel not only in performance such as high impact strength but also in weight reduction and high rigidity.

[0003] There has been no conventional molding material for a housing that satisfies the required performance, such as generally having a high impact resistance and inferior thin-wall moldability. Therefore, in recent years, various improvements have been made to the thermoplastic resin composition as a housing molding material by making a polymer alloy, adding various fillers, and the like.

[0004] When the elastomer component is finely dispersed in a thermoplastic resin by polymer alloying, the thermoplastic resin has high impact resistance, but the kneading conditions are difficult, and not only the flowability is reduced, but also the molded product is molded. Also, the rigidity of the housing is reduced. Further, when an inorganic filler such as glass fiber or talc is added to the thermoplastic resin, the bending strength and the tensile strength are improved, but the impact resistance and the thin-wall moldability are reduced. Accordingly, various fillers and elastomer components capable of improving various properties have been devised.

[0005]

For example, Japanese Patent Laid-Open No.
No. 103657 discloses that a core-shell polymer obtained by coating rubber-like polymer particles as an elastic body with a glass-like polymer is dispersed in a thermoplastic resin. However, core-shell polymers are relatively expensive because they are made by an interfacial polymerization method, and require investment in development equipment, so in recent housing development where cost is important, Further, there is a demand for a material which is inexpensive and can be easily developed using only equipment generally owned by a resin manufacturer such as a kneading extruder and a mixer.

There is also a technique in which a maleic anhydride-modified ethylene propylene rubber and an inorganic filler are added to a thermoplastic resin (refer to "Journal of Applied Polymer Scienc").
e) ", 1996, Vol. 61, pp. 1877-1885), because it can be used only for limited resins such as polypropylene (PP), which is unsuitable as a housing material because of its strength. There is a need for a technology that can be applied to plastic resins.

The present invention has been conceived under such circumstances, and is a technique which can be applied to various thermoplastic resins, and is lightweight, has excellent thin-wall moldability, and has a high rigidity. It is an object of the present invention to provide a composite resin material having impact resistance and a housing for an electronic device obtained therefrom.

[0008]

In order to solve the above-mentioned problems, the present invention takes the following technical means.

That is, according to the first aspect of the present invention,
A composite resin material having a structure in which an inorganic filler at least a part of which is coated with an elastic material is dispersed in a thermoplastic resin, wherein the elastic material has an affinity for the inorganic filler. A composite resin having a functional first functional group and a second functional group that is compatible with the thermoplastic resin or is the same as the functional group of the thermoplastic resin. Materials are provided.

The first functional group and the second functional group are selected mainly depending on the type of the thermoplastic resin or the inorganic filler. Even if the first functional group and the second functional group are the same, However, different types are generally adopted. Of course, each may have one type of functional group as the first functional group or the second functional group,
It may have at least a plurality of types of functional groups.

The elastic body may be constituted by a single elastic body, or may be constituted by a plurality of elastic bodies. For example, when configured as a plurality of elastic bodies, the innermost elastic body has the first functional group and the outermost elastic body has the second functional group. of course,
The elastic body may be constituted by two elastic bodies of a first elastic body and a second elastic body. In this case, for example, the first elastic body has the first functional group and covers at least a part of the outer surface of the inorganic filler, and the second elastic body has the second functional group and has the outer surface of the first elastic body. Is configured to cover at least a part of. And it is desired that the second elastic body is compatible with, for example, the first elastic body.

The first functional group and the second functional group may be of any origin, and may be already in the monomer state.
It has a functional group equivalent, and may have a first functional group or a second functional group at the time of polymerization, or may be modified and introduced. of course,
Similarly for functional groups having compatibility with inorganic fillers,
Its origin does not matter.

The first functional group includes a carboxyl group and an epoxy group, and preferably at least one of them is used.

Examples of the second functional group include styrene acrylonitrile group, acryl group, polymethyl methacrylate group, styrene group, polystyrene group, carboxyl group, amino group, acrylamide group, methacrylamide group, epoxy group and acrylonitrile group. Preferably, at least one is selected from the group consisting of these functional groups.

As the thermoplastic resin, acrylonitrile-butadiene-styrene copolymer (ABS) resin, styrene acrylonitrile (AS) resin, polycarbonate (P
C) resin, polystyrene (PS) resin, aromatic polyamide (PA)
Resin, polypropylene (PP) resin, polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT)
Resin, polyether sulfone (PES) resin, polyphenylene ether (PPE) resin, liquid crystal polymer (LCP) resin, etc., and the exemplified resins may be used as a single substance. At least two selected resin alone may be used as a blended polymer alloy.

Here, the following are preferable combinations of the thermoplastic resin and the second functional group. For acrylonitrile-butadiene-styrene copolymer (ABS) resin and styrene acrylonitrile (AS) resin, for example, styrene acrylonitrile group, acrylic group, or polymethyl methacrylate group such as polycarbonate
For (PC) resin, for example, styrene acrylonitrile group, and for aromatic polyamide (PA) resin, for example, carboxyl group, amino group, acrylamide group, or methacrylamide group, polyethylene terephthalate (PET) resin and Polybutylene terephthalate (PB
T) resins, for example, epoxy groups, polyphenylene ether (PPE) resins, styrene groups,
Examples include a polystyrene group and an acrylic group.

Examples of the inorganic filler include calcium carbonate, talc, mica, glass fiber, carbon fiber, kaolin, and clay. The particle size of the inorganic filler is 0.
The range is preferably from 0.1 to 10 μm, and more preferably from 0.1 to 5 μm.
μm range.

On the other hand, according to a second aspect of the present invention, there is provided an electronic device characterized by being obtained by molding any of the composite resin materials described in the first aspect of the present invention. An enclosure is provided.

In the composite resin material having the above-described structure, the first functional group of the elastic body (including a plurality of elastic bodies) has an affinity for the inorganic filler. And the second functional group is compatible with the thermoplastic resin, so that the elastic body constitutes a dispersed phase. That is, a structure in which the inorganic filler is present in the dispersed phase in the thermoplastic resin is obtained. In this structure, the disperse phase has the second functional group having a suitable compatibility with the thermoplastic resin, and the disperse phase and thus the inorganic filler are uniformly dispersed in the thermoplastic resin. As described above, in the present invention, the first functional group or the second functional group may be appropriately selected according to the type of the thermoplastic resin or the inorganic filler, and the technical idea of the present invention is applied to various thermoplastic resins. Is applicable.

Further, in the present invention, the periphery of the inorganic filler is surrounded by the elastic body, and a part of the impact is absorbed by the deformation of the elastic body, but a sufficient effect can be obtained by adding a small amount. Other material properties (fluidity during melting)
Without impairing the impact strength,
A high-performance electronic equipment housing can be created.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to the embodiments. FIG. 1 is a partially enlarged cross-sectional view illustrating an example of the composite resin material of the present invention, and FIG.
FIG. 2 is a diagram illustrating an example of an electronic device housing obtained by molding the composite resin material of FIG. 1.

As shown in FIG. 1, a composite resin material 1 according to the present invention comprises a thermoplastic resin 2 serving as a matrix,
The composite filler 3 is dispersed. The composite filler 3 has a form in which the outer surface of the inorganic filler 30 is covered with the first elastic body 31 and the outer surface of the first elastic body 31 is covered with the second elastic body 32.

The inorganic filler 30 is preferably calcium carbonate, talc, mica, glass, carbon, kaolin or clay, and generally has an average particle size of 0.01 to 10%.
Those having a size of about μm, more preferably those having a size of about 0.01 to 5 μm are used. Although the weight ratio of the inorganic filler 30 in the composite resin material 1 cannot be unambiguously determined, the bending strength and the tensile strength of the composite resin material 1 can be reduced without impairing the fluidity (moldability) of the composite resin material 1. The range is set to a sufficiently secure range, for example, 1 to 30% by weight. In addition, the inorganic filler 30 includes, in addition to the spherical or substantially spherical forms generally considered as particles, those having an elongated form such as fine fibers and those having a flat form. And

The first elastic body 31 has a first functional group having an affinity for the inorganic filler 30. For example, a carboxyl group or an epoxy group as the first functional group is introduced into the elastic body. Those denatured by using are preferably used. Although the weight ratio of the first elastic body 31 in the composite resin material 1 cannot be unambiguously determined, it does not impair the fluidity (moldability) of the composite resin material 1 and other components (in particular, the inorganic filler 30). Considering the addition amount of
４０40% by weight.

The carboxyl group in this case includes an unsaturated carboxylic acid or an anhydride thereof such as acrylic acid or methacrylic acid which is a monocarboxylic acid, maleic acid, fumaric acid and itaconic acid which are dicarboxylic acids, or an anhydride of dicarboxylic acid. Anhydride, maleic anhydride, itaconic anhydride, and endo-bicyclo- [2,2,1] -5-heptene-2,3-dicarboxylic anhydride (hymic anhydride). Among them, a polymer modified with a dicarboxylic acid and its anhydride is suitably used. On the other hand, examples of the epoxy group include glycidyl methacrylate and glycidyl acrylate.

The elastic body to be modified includes copolymer rubbers of two or more α-olefins such as ethylene, propylene, 1-butene, 1-hexene and 4-methyl-pentene, or Copolymer rubbers of α-olefins and other types of monomers are exemplified. Examples include ethylene-propylene copolymer rubber (EPR), ethylene-butene copolymer rubber (EBR), and ethylene-propylene-diene copolymer rubber (EPDM). As the diene in the ethylene-propylene-diene copolymer rubber (EPDM), a non-conjugated diene such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene and methylene norbornene, or a conjugated diene such as butadiene and isoprene is used. can do. Further, as another type of monomer copolymerized with the α-olefin, vinyl acetate, acrylate, or the like can be used. Examples of the copolymer with another type of monomer include an ethylene-vinyl acetate copolymer (EVA). Further, in the present invention, hydrogenated styrene-
Butadiene block copolymer (SEBS: styrene-ethylene / butylene-styrene block copolymer) and hydrogenated styrene-isoprene block copolymer (SEPS: styrene-
In addition to elastic bodies such as ethylene-propylene-styrene block copolymer), elastic bodies such as polyisoprene, polybutadiene, polychloroprene, polyacrylonitrile-butadiene copolymer, polystyrene-butadiene copolymer, and polystyrene-isoprene copolymer can also be mentioned as modification targets.

The second elastic body 32 has at least a second functional group compatible with the thermoplastic resin 2, and is also compatible with the first elastic body 31. Specifically, styrene acrylonitrile group, acrylic group,
Polymethyl methacrylate group, styrene group, polystyrene group, carboxyl group, amino group, acrylamide group, methacrylamide group, epoxy group and acrylonitrile group having a second functional group, preferably, styrene group, acrylonitrile group At least one selected from, an epoxy group and a carboxyl group
A polymer having two functional groups is employed.

As the second elastic body 32, an elastic body modified in the same manner as the above-described first elastic body 31 can be used. In this case, the object to be modified in the first elastic body 31 described above is used. May be modified by a functional group such as a styrene group, an acrylonitrile group, an epoxy group and a carboxyl group. However, when the elastic body to be modified is the same as the first elastic body 31,
At least one of the functional groups to be introduced is the first elastic body 3
It must be different from 1. Although the weight ratio of the second elastic body 32 in the composite resin material 1 cannot be unambiguously determined, it is, for example, 1 to 40% by weight for the same reason as the first elastic body 31.

Specific examples of the thermoplastic resin 2 include acrylonitrile-butadiene-styrene copolymer (ABS) resin, polycarbonate (PC) resin, polystyrene (PS) resin, aromatic polyamide (PA) resin, and polypropylene (PP). Resin, polybutylene terephthalate (PBT) resin, polyethersulfone (PES) resin, polyphenylene ether (PP
E) resin, liquid crystal polymer (LCP) resin and the like. In addition, a resin obtained by arbitrarily blending these resin simple substances may be used. For example, ABS / PC resin,
PA / PPE resin, PA / PP resin, PC / PS resin, PPE / PS resin, AB
Examples thereof include polymer alloys such as S / PPE resin, and those obtained by blending an LCP resin with the above resin alone or polymer alloy to improve the fluidity. Furthermore, inorganic fillers such as carbon fiber, glass fiber, boron fiber, and Tyranno fiber, Kevlar fiber, PB
It may be reinforced by adding an organic filler such as T fiber. The inorganic filler and the organic filler referred to here are added to improve the strength of the thermoplastic resin 1, and are distinguished from the inorganic filler 30 covered by the first and second elastic bodies 31 and 32. . That is,
When these fillers are added, each of the elastic bodies 31,
It is dispersed in the thermoplastic resin without being covered by 32. The weight ratio of the thermoplastic resin 2 is, for example, 50 to 97% by weight.

In FIG. 1, the entire outer surface of the inorganic filler 30 is covered with the first elastic body 31,
Although the entire outer surface of the elastic body 31 is covered with the second elastic body, the first elastic body 31 covers at least a part of the inorganic filler 30, and the second elastic body 32 is formed of the first elastic body. It suffices if at least a part of 31 is covered. Moreover, you may comprise so that the inorganic filler 30 may be covered with a single elastic body.

The above-mentioned composite resin material 1 is preliminarily mixed with a thermoplastic resin 2, an inorganic filler 30, a first elastic body 31, and a second elastic body 32 in a desired weight ratio, for example. It is obtained by melt-kneading with a twin-screw extruder or the like. When each component is melt-kneaded,
Since the first elastic body 31 has an affinity for the inorganic filler 30, the inorganic filler 30 is covered with the first elastic body. Since the second elastic body 32 has compatibility with both the first elastic body 31 and the thermoplastic resin, the first elastic body 31 is covered with the second elastic body 32,
Inorganic filler 30 covered by each elastic body 31, 32
Are uniformly dispersed in the thermoplastic resin 2.

Then, by molding the composite resin material 1 into a predetermined shape by an injection molding method or the like, an electronic device housing as shown in FIG. 2, for example, is obtained. The electronic device housing 5 shown in FIG. 1 is configured for a mobile phone. The shape is a box shape with the lower part opened as a whole, and a plurality of through holes 50 and 51 for a push button and a display part are provided on the upper surface. The vertical dimension in plan view is 10c.
m, and the width dimension is 5 cm.

In the present embodiment, the inorganic filler 30 is covered with a first elastic body 31 having an affinity for the inorganic filler 30, and the first elastic body 31 is further covered by a second elastic body 32 having compatibility with the thermoplastic resin 2. A coated structure is employed. That is, the first elastic body 31 is required to have an affinity for the inorganic filler 30, and the second elastic body 32 is required to have compatibility with at least the thermoplastic resin 2. Is required to have compatibility with the first elastic body 31. First elastic body 31
It is needless to say that the condition of having an affinity for the inorganic filler 30 required for the above can be satisfied relatively easily. On the other hand, since both the first elastic body 31 and the thermoplastic resin 2 are polymers, it is not so difficult to satisfy the conditions required for the second elastic body 32, such as being compatible with both. As described above, the conditions individually required for each of the elastic bodies 31 and 32 can be relatively easily satisfied, and even if it is required to satisfy each of the conditions at the same time, a single elastic body is required. Compared to the case where similar conditions are required, it is much easier to satisfy. Therefore, there are many combinations of the first elastic body 31, the second elastic body 32, and the thermoplastic resin 2 to which the present invention can be applied, and as a result, the present invention can be widely applied to a general thermoplastic resin 2. become.

In the composite resin material having the above-described structure,
The first elastic body 31 and the second elastic body 3 in the thermoplastic resin 2
2 is formed, and a structure in which the inorganic filler 30 is present in the dispersed phase is obtained. In this structure, since the outer surface of the dispersed phase is constituted by the second elastic body 32 having an appropriate compatibility with the thermoplastic resin 2, the dispersed phase and thus the inorganic filler 30 are uniformly dispersed in the thermoplastic resin 2. It will be distributed.

[0035]

Next, examples of the present invention will be described together with comparative examples.

[0036]

Example 1 The average particle size of the inorganic filler was 1.5 μm
5 parts by weight of calcium carbonate (trade name: Nanox # 30, manufactured by Maruo Calcium Co., Ltd.), maleic anhydride-modified ethylene-propylene-diene copolymer (trade name: Royal Tough 490, Shiraishi calcium) as a first elastic body (stock)
5 parts by weight), 2 parts by weight of a styrene acrylonitrile-modified ethylene-propylene-diene copolymer (trade name: Royal Tough 372P20, manufactured by Shiraishi Calcium Co., Ltd.) as a second elastic body, and polycarbonate (a thermoplastic resin) PC) 88 parts by weight of a resin (trade name: H4000, manufactured by Mitsubishi Engineering-Plastics Co., Ltd.) are preliminarily mixed, and the mixture is heated at about 270 ° C. using a twin-screw extruder (trade name: 30C150, manufactured by Toyo Seiki Co., Ltd.). After performing melt kneading,
Injection molding machine (product name: 100 ton, Niigata Iron and Steel Co., Ltd.)
) Was used to form an electronic device housing as shown in FIG. The performance of this electronic device housing was evaluated by a drop weight test and a one-point load test described below. together,
The fluidity of the composite resin material during injection molding was also evaluated.

[Dropping Weight Test] A plurality of electronic device housings for evaluation are formed, and a hard ball (100 g) is dropped on the electronic device housing according to JIS-K7211, and 50% of the number of housings is broken. The height at that time (50% breaking height) was determined, and the impact strength of the housing was evaluated based on the height.

[Single-point load test] The electronic device housing for evaluation is supported, a load is intensively applied to the center portion of the housing, and this load is gradually increased to obtain a load when the housing is broken. The rigidity of the housing was evaluated from [kgf / cm ² ].

[Fluidity during molding] The fluidity when the composite resin material was poured from the injection molding machine into the molding die was visually evaluated.

[0040]

Embodiment 2 In this embodiment, an acrylonitrile-butadiene-styrene copolymer (A) was used as a thermoplastic resin.
BS) Resin (trade name: Stylac 191F, Asahi Kasei Corporation)
Ex.) Was used to form an electronic device housing in the same manner as in Example 1, and each evaluation was performed.

[0041]

Example 3 In this example, a styrene acrylonitrile-modified ethylene-propylene-diene copolymer (trade name:
An organic peroxide (trade name: 94 parts by weight of Royal Tough 372P20, manufactured by Shiraishi Calcium Co., Ltd.) and 5 parts by weight of maleic anhydride (trade name: Crystal MAN, manufactured by NOF CORPORATION)
In the presence of 1 part by weight of Parchable P (manufactured by Nippon Oil & Fats Co., Ltd.), melt kneading was performed at about 200 ° C. with a twin screw extruder to form an elastic body. Calcium carbonate (trade name: Nanox # 30, manufactured by Maruo Calcium Co., Ltd.) and acrylonitrile-butadiene-styrene copolymer (ABS) resin (trade name: Sebian 680SF, manufactured by Daicel Chemical Industries, Ltd.) At a weight ratio of 5:90,
After melt-kneading at about 220 ° C. using a twin-screw extruder, an electronic device housing as shown in FIG. 2 was molded using an injection molding machine. The performance of the electronic device housing was evaluated by the drop weight test and the one-point load test described above, and the fluidity of the composite resin material during injection molding was also evaluated.

[0042]

Embodiment 4 In this embodiment, a polycarbonate (PC) resin (trade name: H4000,
An electronic device housing was molded in the same manner as in Example 3 except that Mitsubishi Engineer Plastics Co., Ltd.) was used, and each evaluation was performed.

[0043]

Embodiment 5 In this embodiment, styrene acrylonitrile (AS) resin (trade name: Sebian) was used as the thermoplastic resin.
-N050, manufactured by Daicel Chemical Industries, Ltd.) was used to form electronic device housings in the same manner as in Example 3, and each evaluation was performed.

[0044]

Comparative Example 1 In this comparative example, an electronic device was prepared in the same manner as in Example 3 except that the inorganic filler (calcium carbonate) was not added and the weight ratio between the elastic body and the ABS resin was 10:90. The housing was molded and each evaluation was performed.

[0045]

Comparative Example 2 In this comparative example, no elastic body was added.
An electronic device housing was molded in the same manner as in Example 3 except that the weight ratio between the inorganic filler (calcium carbonate) and the ABS resin was 5:90, and each evaluation was performed.

[0046]

COMPARATIVE EXAMPLE 3 In this comparative example, an electronic device housing was formed of an ABS resin alone without adding an elastic body and an inorganic filler (calcium carbonate), and each evaluation was performed.

[0047]

Comparative Example 4 In this comparative example, an electronic device was prepared in the same manner as in Example 4 except that the inorganic filler (calcium carbonate) was not added and the weight ratio between the elastic body and the PC resin was 10:90. The housing was molded and each evaluation was performed.

[0048]

Comparative Example 5 In this comparative example, no elastic body was added.
An electronic device housing was molded in the same manner as in Example 4 except that the weight ratio between the inorganic filler (calcium carbonate) and the PC resin was 5:90, and each evaluation was performed.

[0049]

COMPARATIVE EXAMPLE 6 In this comparative example, an electronic device housing was formed of a PC resin alone without adding an elastic body and an inorganic filler (calcium carbonate), and each evaluation was performed.

[0050]

Comparative Example 7 In this comparative example, an electronic device was manufactured in the same manner as in Example 5 except that the inorganic filler (calcium carbonate) was not added and the weight ratio between the elastic body and the AS resin was 10:90. The housing was molded and each evaluation was performed.

[0051]

Comparative Example 8 In this comparative example, no elastic body was added.
An electronic device housing was molded in the same manner as in Example 5 except that the weight ratio between the inorganic filler (calcium carbonate) and the AS resin was 5:90, and each evaluation was performed.

[0052]

COMPARATIVE EXAMPLE 9 In this comparative example, an electronic device housing was formed of an AS resin alone without adding an elastic body and an inorganic filler (calcium carbonate), and each evaluation was performed.

[0053]

[Table 1]

As shown in Table 1, a composite resin in which a composite inorganic filler in which an inorganic filler is covered by a single elastic body or two elastic bodies is dispersed in a PC resin or an ABS resin. The electronic device housing obtained from the material (Examples 1 to 4) has a lower weight test than the electronic device housing (Comparative Example 3 or Comparative Example 6) obtained from PC resin or ABS resin alone. 50% determined by
The fracture height is excellent, and the strength and fluidity determined by the one-point load test are almost the same. In addition, compared to the electronic device housings (Comparative Examples 1 and 2, and Comparative Examples 4 and 5) obtained from a composite resin material obtained by adding only an inorganic filler or only an elastic body to a resin alone, the present invention is also applicable. The electronic device housings of Examples 1 to 4 are excellent in 50% breaking height and strength.

Even when the AS resin is used as the thermoplastic resin (Example 5, Comparative Examples 7 to 9), PC
The same results as those of the resin and the ABS resin are obtained.

[0056]

As described above, the present invention can be applied not only to various thermoplastic resins, but also to a composite resin material, in which the fluidity of the resin at the time of molding is ensured and the electronic properties as desired. The device housing can be formed, and the effect of improving the impact resistance of the formed electronic device housing and ensuring high strength can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially enlarged sectional view showing an example of a composite resin material of the present invention.

FIG. 2 is a view showing an example of an electronic device housing obtained from the composite resin material of the present invention.

[Explanation of symbols]

 Reference Signs List 1 composite resin material 2 thermoplastic resin 3 composite filler 30 inorganic filler 31 first elastic body 32 second elastic body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenshin Ishizuka 4-1-1 Kamikadanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Takayuki Fujiwara 4-1-1 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture No. 1 Fujitsu Limited F term (reference) 4J002 BB121 BC031 BC061 BN151 CF061 CF071 CF181 CG001 CL061 CN011 CN031 DA016 DE236 DJ036 DJ046 DJ056 DL006 FA046 FB266 GQ00 5K023 AA07 BB03 BB27 LL06 QQ05

Claims (9)

[Claims] 1. A composite resin material having a structure in which an inorganic filler at least a part of an outer surface of which is coated with an elastic material is dispersed in a thermoplastic resin, wherein the elastic material is A composite resin material comprising: a first functional group having an affinity for a material; and a second functional group having a compatibility with the thermoplastic resin. 2. The method according to claim 1, wherein the first functional group and the second functional group are
The composite resin material according to claim 1, which is a different type of functional group. 3. The elastic body comprises two elastic bodies, a first elastic body and a second elastic body, wherein the first elastic body has the first functional group and an outer surface of the inorganic filler. And the second elastic body has the second functional group,
The composite resin material according to claim 1, wherein the composite resin material covers at least a part of an outer surface of the first elastic body. 4. The method according to claim 1, wherein the first functional group or the second functional group is obtained by modifying and introducing a polymer.
4. The composite resin material according to any one of items 1 to 3. 5. The composite resin material according to claim 1, wherein said first functional group is at least one of a carboxyl group and an epoxy group. 6. The second functional group is selected from styrene acrylonitrile group, acryl group, polymethyl methacrylate group, styrene group, polystyrene group, carboxyl group, amino group, acrylamide group, methacrylamide group, epoxy group and acrylonitrile group. The composite resin material according to any one of claims 1 to 5, wherein the composite resin material is at least one selected from the group consisting of: 7. The thermoplastic resin is an acrylonitrile-butadiene-styrene copolymer resin, styrene acrylonitrile resin, polycarbonate resin, polystyrene resin, aromatic polyamide resin, polypropylene resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyether The composite resin material according to any one of claims 1 to 6, wherein the composite resin material is a sulfone resin, a polyphenylene ether resin, a liquid crystal polymer resin, or a polymer alloy obtained by blending at least two resins selected from the group consisting of these resins. . 8. The inorganic filler has a particle size of 0.01-1.
The composite resin material according to any one of claims 1 to 7, which is 0 µm of calcium carbonate, talc, mica, glass fiber, carbon fiber, kaolin, or clay. 9. An electronic device housing obtained by molding the composite resin material according to claim 1. Description: