JP2006089572A - Electronic equipment package and molding material therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding material for an electronic equipment package, which is capable of molding the electronic equipment package equipped with a large mechanical strength and a good appearance. <P>SOLUTION: The molding material for the electronic equipment package contains a base resis 6, a filler and an elastomer 9, wherein the base resin 6 contains polyamide and polyphenylene ether. The filler contains a long-fiber filler 7 and a short-fiber filler 8, wherein the short-fiber filler 8 has an aspect ratio smaller than that of the long-fiber filler 7. The molding material is used to mold the package 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a molding material for an electronic device casing and an electronic device casing used for molding a casing of an electronic device such as a mobile phone or a PDA (Personal Digital Assistant).

  High injection pressure and injection speed are required at the time of molding of a thermoplastic resin because of the demand for thinning of the casing accompanying the recent thinning of electronic devices. Further, a thermoplastic resin as a molding material is required to have high fluidity during molding and to improve the mechanical strength of the molded product. Under such circumstances, in injection molding, which is a general molding method for electronic equipment casings, precise control and high-speed injection have become possible with electric servos and high-performance accumulators. On the other hand, as molding materials for electronic device casings, thermoplastic resins filled with a high proportion of fillers such as glass, carbon, ceramics, etc., have been used, and molded products as required by conventional injection molding methods It has become difficult to obtain.

  In general, since the mechanical strength of a molded product is drastically reduced during thin-wall molding, a method of improving the strength by adding a fibrous filler such as glass fiber or carbon fiber to a molding material is used (see, for example, Patent Document 1). .) Thereby, compared with the case where a filler is not added, for example, a bending elastic modulus improves 2 to 5 times. However, in the case of injection molding, as the amount of filler added increases, thin-wall molding becomes difficult or the strength of the molded product decreases due to a decrease in fluidity during molding and anisotropy in shrinkage. Problems such as warping and warping often occur.

  On the other hand, high fluidity, dimensional stability, and mechanical strength are required for a thermoplastic resin that is a base material of a molding material used for injection molding. So-called amorphous resins such as commonly used ABS resins and polycarbonates have good dimensional stability and paintability, but because of their poor fluidity, it is not possible to mix a large amount of filler with these matrix resins. Can not. For this reason, when the rigidity is particularly required, it is not a good idea to use these amorphous resins alone. For example, when a fluidity test is performed on a polycarbonate containing about 40% by weight of glass fiber, it is difficult to form a sheet with a thickness of 1 mm or less, and defects such as unfilling and burning occur, and sufficient rigidity is obtained. Cannot be obtained. Further, in addition to defects such as unfilling, sink marks in local thick portions (for example, functional parts such as bosses and ribs on the inner surface of the housing) and appearance defects due to floating of the filler on the surface of the molded product are likely to occur. For this reason, it is customary to use materials containing a large amount of filler for internal parts, and generally use materials with a filler content of less than 20% by weight for external parts.

Crystalline resins such as polyamide and polypropylene have slightly poor paintability, but they are highly fluid and can be molded to a maximum thickness of about 0.5 mm even with a material with about 50% glass fiber added. Yes, a molded product with high rigidity can be obtained. However, a decrease in strength due to water absorption or a decrease in dimensional accuracy due to variations in crystallization may adversely affect the thin molded product. For this reason, in order to improve these crystalline resins, the dimensional accuracy of the molded product is improved by a technique of using a non-crystalline resin such as polycarbonate, polyphenylene ether or ABS resin mixed with the crystalline resin, a so-called polymer alloy technique. Improvement has been proposed (see, for example, Patent Document 2 and Patent Document 3).
JP 2003-213137 A JP-A-5-255586 JP-A-7-102168

  When the polymer alloy is used, high mechanical strength can be secured even when a thin molded product is molded. However, even when the above polymer alloy is used, the problem that sink marks are generated in a locally thick portion of the molded product and the appearance of the molded product is deteriorated cannot be sufficiently solved.

  Therefore, the present invention provides a molding material for an electronic device casing that can form an electronic device casing having high mechanical strength and good appearance, and an electronic device casing formed from the molding material.

  The molding material for an electronic device casing of the present invention is an electronic device casing molding material containing a base material resin, a filler, and a thermoplastic elastomer, and the base material resin includes polyamide, polyphenylene ether, and The filler includes a first fibrous filler and a second fibrous filler, and the aspect ratio of the second fibrous filler is that of the first fibrous filler. It is characterized by being smaller than the aspect ratio.

  The electronic device casing of the present invention is obtained by molding the molding material for the electronic device casing.

  By using the molding material for an electronic device casing of the present invention, an electronic device casing having high mechanical strength and good appearance can be provided.

  First, an embodiment of the molding material for an electronic device casing of the present invention will be described. An example of the molding material for an electronic device casing of the present invention is an electronic device casing molding material containing a base resin containing polyamide and polyphenylene ether, a filler, and a thermoplastic elastomer. The filler includes a first fibrous filler and a second fibrous filler, and the aspect ratio of the second fibrous filler is an aspect ratio of the first fibrous filler. Less than the ratio.

  Adds heat resistance, flexibility and dimensional stability to the molded product while maintaining the fluidity of the molding material by mixing polyphenylene ether with the most fluid polyamide among injection-moldable thermoplastic resin materials be able to. Moreover, the mechanical strength of a molded article can be raised by using a filler. Furthermore, by using a thermoplastic elastomer, it is possible to prevent a decrease in toughness of the molded product due to the addition of a filler.

  In addition, by using two types of fibrous fillers having different aspect ratios as the filler, the orientation of the fibrous filler having a large aspect ratio is disturbed by the fibrous filler having a small aspect ratio, and molding is performed. Shrinkage in the thickness direction of the product is suppressed, and the occurrence of sink marks in the locally thick part of the molded product can be prevented.

  Examples of the polyamide include polyamide 4, polyamide 6, polyamide 6,6, polyamide 11, polyamide 12, polyamide 6,3, polyamide 6,4, polyamide 4,6, polyamide 6/10, polyamide 12, and terephthalic acid. And / or polyamides made from isophthalic acid and trimethylhexamethylenediamine, polyamides made from adipic acid and m-xylylenediamine, adipic acid, azelaic acid and 2,2-bis- (p-aminocyclohexyl) propane Polyamides produced from terephthalic acid and polyamides produced from 4,4-diaminodicyclohexylmethane can be suitably used.

  Further, the content of the polyamide is preferably 50% by weight or more and 70% by weight or less, and more preferably 60% by weight or more and 70% by weight or less in terms of the weight ratio of the whole base resin. This is because, within this range, the flowability of the molding material can be maintained high, so that the occurrence of burrs and warpage can be reduced and the mechanical strength of the molded product can be prevented from being lowered.

  Examples of the polyphenylene ether include poly (2,6-dimethyl-1,4-phenylene) ether, 2,6-dimethyl-1,4-phenol / 2,3,6-trimethyl-1,4-phenol, and the like. Polymer, poly (2,6-diethyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4-phenylene) ) Ether, poly (2-methyl-6-propyl-1,4-phenylene) ether, poly (2,6-diallyl-1,4-phenylene) ether, poly (2-methyl-6-allyl-1,4) -Phenylene) ether, poly (2,6-dibromo-1,4-phenylene) ether, poly (2,6-dichloro-1,4-phenylene) ether, poly (2-chloro-6-butyl) Mo-1,4-phenylene) ether, poly (2,6-difluoro-1,4-phenylene) ether, poly (2,3,6-trimethyl-1,4-phenylene) ether, poly (2,3,3) 5,6-tetrabromo-1,4-phenylene) ether or the like can be preferably used.

  The content of the polyphenylene ether is preferably 30% by weight or more and 50% by weight or less, and more preferably 30% by weight or more and 40% by weight or less, based on the weight ratio of the whole base resin. This is because within this range, heat resistance, flexibility and dimensional stability can be sufficiently added to the molded product without lowering the fluidity of the molding material. Moreover, since the heat resistant temperature of polyphenylene ether is twice or more that of polyamide, it is possible to suppress deformation of the molded product due to high heat during molding.

  As the first fibrous filler, for example, glass fiber, carbon fiber, metal fiber, organic fiber, and the like can be used. From the viewpoint of improving the impact resistance of the molded product and material cost, glass fiber is used. Preferably, carbon fiber is preferable from the viewpoint of improving the rigidity of the molded product. Further, the aspect ratio of the first fibrous filler is preferably 250 to 1000, and more preferably 300 to 650. This is because within this range, the mechanical strength of the molded product can be improved, and fibrous fillers having these aspect ratios can be easily obtained. In this specification, the aspect ratio refers to the ratio (L / D) of the diameter (D) and the length (L) of the fibrous filler. The content of the first fibrous filler is preferably 10% by weight or more and 50% by weight or less, more preferably 20% by weight or more and 50% by weight or less, based on the weight ratio of the whole molding material for electronic device casing. preferable. This is because within this range, the bending elastic modulus of the molded product can be improved while maintaining the fluidity of the molding material.

  As the second fibrous filler, a mineral-based fibrous filler can be suitably used. For example, a fibrous filler made of calcium silicate, potassium titanate, aluminum borate, or the like can be used. In addition, the aspect ratio of the second fibrous filler is preferably 10 to 200, and more preferably 50 to 150. This is because within this range, the mechanical strength of the molded product can be improved, and fibrous fillers having these aspect ratios can be easily obtained. The content of the second fibrous filler is preferably 5% by weight or more and 10% by weight or less, more preferably 7% by weight or more and 10% by weight or less, based on the weight ratio of the whole molding material for electronic device casing. preferable. This is because the molding shrinkage of the molded product can be reduced within this range.

  As said thermoplastic elastomer, a styrene-type elastomer, an olefin-type elastomer, etc. are preferable. These elastomers can be finely dispersed in the polyamide by adding maleic anhydride having high reactivity with the polyamide. In particular, the styrene elastomer has high compatibility with polyphenylene ether, and can impart flexibility to the entire alloy system. Further, the content of the thermoplastic elastomer is preferably 1% by weight or more and 10% by weight or less, and more preferably 5% by weight or more and 10% by weight or less in terms of the weight ratio of the whole molding material for electronic device casing. This is because within this range, the impact resistance can be improved while maintaining the heat resistance of the molded product.

  Next, an embodiment of the electronic device casing of the present invention will be described. The electronic device casing of the present invention is a casing used for electronic devices such as mobile phones, PDAs, and personal computers, particularly small electronic devices, and the molding material for electronic device casings described in the above embodiment is used. It was molded using. By molding the casing using the molding material for the electronic apparatus casing, it is possible to provide an electronic apparatus casing having high mechanical strength and good appearance with suppressed occurrence of sink marks. In addition, the electronic device casing of the present embodiment can maintain high mechanical strength and good appearance even when the thickness is 0.5 mm or more and 2 mm or less.

  An injection molding method is used as a method of molding the electronic device casing of the present embodiment, but a transfer molding method (compression molding method) or the like can also be used.

  Subsequently, shrinkage in the thickness direction is suppressed in the electronic device casing molded using the molding material for the electronic device casing of the present embodiment based on the drawings, and the occurrence of sink marks in the locally thick part of the molded product The reason why is suppressed will be specifically described.

  FIG. 1 is a sectional view (A) of a main part showing an example of a casing molded using a conventional molding material, and a sectional view of a major part showing an example of a casing molded using the molding material of the present embodiment (A). B). In FIG. 1A, a conventional case 3 is formed by injection molding using a base material resin 1 made of polyamide to which a fibrous filler 2 made of glass fiber is added as a conventional molding material. 1A, the housing 3 includes a thin portion 3a and a thick portion 3b such as a rib, and the thick portion 3b has a hollow portion 3c therein. As shown in FIG. 1A, when a conventional molding material is used, the fibrous filler 2 is oriented along the flow of the base resin 1 at the time of injection molding. Therefore, when contraction of the base resin 1 occurs in the contraction directions 4a and 4b in the thick portion 3b, the fibrous filler 2 does not become resistant to the contraction, and sink marks 5a and 5b are formed in the housing 3. Will occur.

  On the other hand, in FIG. 1B, as a molding material of the present embodiment, a base fiber resin 6 made of polyamide and polyphenylene ether, a long fiber filler 7 made of glass fiber, and a short fiber filler 8 made of calcium silicate fiber. And the case 10 of this embodiment was shape | molded by injection molding using what added the elastomer 9 which consists of a styrene elastomer. In FIG. 1B, the housing 10 includes a thin portion 10a and a thick portion 10b such as a rib, and the thick portion 10b has a hollow portion 10c therein. As shown in FIG. 1B, even when the molding material of this embodiment is used, the long fibrous filler 7 is oriented along the flow of the base resin 6 during the injection molding. However, unlike FIG. 1A, short fiber filler 8 and elastomer 9 exist around the long fiber filler 7. Therefore, even if shrinkage of the base resin 6 occurs in the shrinkage directions 11a and 11b in the thick wall portion 10b, the short fiber filler 8 and the elastomer 9 generate resistance forces 12a and 12b against the shrinkage. The occurrence of sink marks on the body 10 can be suppressed.

(Example)
Hereinafter, the present invention will be specifically described based on examples.

  A mixture of 60 parts by weight of polyamide “Novamid” (trade name) manufactured by Mitsubishi Engineering Plastics Glass Co., Ltd. and 40 parts by weight of polyphenylene ether “Zylon” (trade name) manufactured by Asahi Kasei Chemicals was prepared as a base resin. . To 45 parts by weight of the base resin, 40 parts by weight of glass fiber (average diameter 10 μm, average length 3 mm, average aspect ratio 300) manufactured by Nippon Sheet Glass Co., Ltd., calcium silicate fiber (average diameter 1 μm, average length) manufactured by Kawatetsu Mining Co., Ltd. The molding material of Example 1 was produced by mixing 10 parts by weight with a thickness of 100 μm and an average aspect ratio of 100) and 5 parts by weight of a styrene elastomer “NOFALOY” (trade name) manufactured by NOF Corporation.

  Next, the housing of the folded cellular phone 13 shown in FIG. 2 was molded by injection molding (injection temperature 250 ° C., injection pressure 180 MPa) using the molding material. Among them, a casing (10 cm in length, 5 cm in width, 1 mm in thickness) on the button arrangement surface side of the main body 14 of the mobile phone 13 was used as a casing sample of this example.

(Comparative Example 1)
A mixture of 60 parts by weight of polyamide “Novamid” (trade name) manufactured by Mitsubishi Engineering Plastics Glass Co., Ltd. and 40 parts by weight of polyphenylene ether “Zylon” (trade name) manufactured by Asahi Kasei Chemicals was prepared as a base resin. . A molding material of Comparative Example 1 was prepared by mixing 50 parts by weight of the base resin with 50 parts by weight of glass fiber (average diameter 10 μm, average length 3 mm, average aspect ratio 300) manufactured by Nippon Sheet Glass. A housing sample was produced in the same manner as in Example 1 using the molding material of Comparative Example 1.

(Comparative Example 2)
A mixture of 60 parts by weight of polyamide “Novamid” (trade name) manufactured by Mitsubishi Engineering Plastics Glass Co., Ltd. and 40 parts by weight of polyphenylene ether “Zylon” (trade name) manufactured by Asahi Kasei Chemicals was prepared as a base resin. . To 50 parts by weight of the base resin, 40 parts by weight of glass fiber (average diameter 10 μm, average length 3 mm, average aspect ratio 300) manufactured by Nippon Sheet Glass Co., Ltd. and styrene elastomer “NOFALOY” (trade name) 10 manufactured by Nippon Oil & Fats The molding material of Comparative Example 2 was produced by mixing parts by weight. Using the molding material of Comparative Example 2, a housing sample was produced in the same manner as in Example 1.

(Comparative Example 3)
A mixture of 60 parts by weight of polyamide “Novamid” (trade name) manufactured by Mitsubishi Engineering Plastics Glass Co., Ltd. and 40 parts by weight of polyphenylene ether “Zylon” (trade name) manufactured by Asahi Kasei Chemicals was prepared as a base resin. . To 50 parts by weight of the base resin, 40 parts by weight of glass fiber (average diameter 10 μm, average length 3 mm, average aspect ratio 300) manufactured by Nippon Sheet Glass Co., Ltd. and calcium silicate fiber (average diameter 1 μm, average length) manufactured by Kawatetsu Mining Co., Ltd. The molding material of Comparative Example 3 was produced by mixing 10 parts by weight with a thickness of 100 μm and an average aspect ratio of 100). Using the molding material of Comparative Example 3, a housing sample was produced in the same manner as in Example 1.

  Here, the component ratios of the molding materials of Example 1 and Comparative Examples 1 to 3 are shown in Table 1. In Table 1, the component ratio is shown as a weight ratio (% by weight) with respect to the entire molding material. However, the ratio (PA / PPE) of polyamide (PA) and polyphenylene ether (PPE) in the base resin is indicated by the respective weight ratio (wt%) with respect to the entire base resin.

  Subsequently, rigidity, impact resistance, and appearance were measured using the case samples of Example 1 and Comparative Examples 1 to 3. The rigidity was measured by measuring the amount of displacement when both ends in the longitudinal direction of the housing sample were placed on a table and a concentrated load of 10 kgf was applied to the central portion of the housing sample. The impact resistance was measured by measuring the scale of destruction (maximum crack length) when a weight of about 100 g was dropped from a height of 30 cm onto the center of the housing sample. Appearance was measured by measuring the amount of sink marks in the height direction on a rib having a height of 1 mm, a width of 1 mm, and a length of 3 mm provided on the back surface of the housing sample. The results are shown in Table 2.

  From Table 2, it can be seen that Example 1 has higher impact resistance (mechanical strength) and better appearance than Comparative Examples 1 to 3.

  Next, the optimum amount of each component of the molding material used in Example 1 was examined. Specifically, a housing sample was molded in the same manner as in Example 1 while changing the weight ratio of each component of the molding material, and the bending elastic modulus, molding shrinkage rate, and Izod impact value of the housing sample were measured. The results are shown in FIGS.

  FIG. 3 is a graph showing the relationship between the amount of glass fiber added and the flexural modulus. In FIG. 3, the weight ratio of the glass fiber to the whole molding material is changed. However, the weight ratio of the base material resin was increased or decreased according to the change in the weight ratio of the glass fiber, and the weight ratio of the other components excluding the base material resin was kept constant. In addition, the flexural modulus was tested for each case sample in accordance with JIS K 7055 using a universal testing machine “Instron 5581” (trade name) manufactured by Instron Japan. It was measured. FIG. 3 shows that the amount of glass fiber added is preferably 10% by weight or more. However, if it exceeds 50% by weight, the fluidity of the molding material may be lowered, so 50% by weight or less is preferable.

  FIG. 4 is a diagram showing the relationship between the amount of calcium silicate fiber added and the molding shrinkage. In FIG. 4, the weight ratio of the calcium silicate fiber with respect to the whole molding material is changed. However, the weight ratio of the base material resin was increased or decreased according to the change in the weight ratio of the calcium silicate fiber, and the weight ratio of the other components excluding the base material resin was made constant. Further, the molding shrinkage rate was determined according to the following formula from the vertical / horizontal / thickness dimensions of the housing sample and the mold dimensions corresponding to these dimensions.

Mold Shrinkage Ratio = (Mold Size−Mold Product Size) / Mold Size FIG. 4 shows that the amount of calcium silicate fiber added is preferably 5% by weight or more. However, if it exceeds 10% by weight, the fluidity of the molding material may be lowered, so 10% by weight or less is preferable.

  FIG. 5 is a graph showing the relationship between the amount of elastomer added and the Izod impact value. In FIG. 5, the weight ratio of the elastomer to the whole molding material is changed. However, the weight ratio of the base material resin was increased or decreased according to the change in the weight ratio of the elastomer, and the weight ratio of the other components excluding the base material resin was kept constant. Further, the Izod impact value is measured by performing an Izod impact test on each case sample in accordance with JIS K 7110 using an Izod impact tester “B-121202403” (trade name) manufactured by Toyo Seiki Co., Ltd. did. FIG. 5 shows that the amount of elastomer added is preferably 1% by weight or more. However, if it exceeds 10% by weight, the heat resistance of the molding material may be lowered, so 10% by weight or less is preferable.

  The following additional notes are further disclosed with respect to the embodiments of the present invention including Examples 1 and 2 above.

(Supplementary note 1) A molding material for an electronic device casing containing a base material resin, a filler, and a thermoplastic elastomer,
The base material resin includes polyamide and polyphenylene ether,
The filler includes a first fibrous filler and a second fibrous filler,
The molding material for an electronic device casing, wherein the aspect ratio of the second fibrous filler is smaller than the aspect ratio of the first fibrous filler.

  (Additional remark 2) The molding material for electronic device housing | casings of Additional remark 1 whose aspect ratio of a said 1st fibrous filler is 250-1000.

  (Additional remark 3) The molding material for electronic device housing | casing of Additional remark 1 whose aspect ratio of a said 2nd fibrous filler is 10-200.

  (Additional remark 4) The said 1st fibrous filler is a molding material for electronic device housing | casing of Additional remark 1 or 2 which is at least 1 chosen from glass fiber and carbon fiber.

  (Additional remark 5) The said 2nd fibrous filler is a molding material for electronic device housing | casing of Additional remark 1 or 3 which is at least 1 chosen from calcium silicate, potassium titanate, and aluminum borate.

  (Additional remark 6) Content of the said 1st fibrous filler is either 10 weight% or more and 50 weight% or less in the weight ratio of the said whole molding material for electronic device housings in any one of Additional remark 1, 2 or 4 The molding material for electronic device housings as described.

  (Additional remark 7) Content of the said 2nd fibrous filler is 5 weight% or more and 10 weight% or less in the weight ratio of the said whole molding material for electronic device housings in any one of Additional remark 1,3 or 5 The molding material for electronic device housings as described.

  (Additional remark 8) Content of the said polyamide is the molding material for electronic device housing | casing of Additional remark 1 which is 50 to 70 weight% in the weight ratio of the said whole base resin.

  (Additional remark 9) Content of the said polyphenylene ether is a molding material for electronic device housing | casing of Additional remark 1 which is 30 to 50 weight% in the weight ratio of the said whole base resin.

  (Additional remark 10) The said thermoplastic elastomer is a molding material for electronic device housing | casing of Additional remark 1 which is at least 1 chosen from a styrene-type elastomer and an olefin-type elastomer.

  (Additional remark 11) The content of the said thermoplastic elastomer is 1 weight% or more and 10 weight% or less in the weight ratio of the said whole molding material for electronic device casings, The molding material for electronic device cases of Additional remark 1 or 10 .

  (Additional remark 12) The electronic device housing | casing which shape | molded the molding material for electronic device housings in any one of Additional remarks 1-11.

(Appendix 13)
The electronic device housing according to appendix 12, wherein the thickness of the electronic device housing is 0.5 mm or more and 2 mm or less.

Sectional view (A) of relevant parts showing an example of a case molded using a conventional molding material, and sectional view (B) of relevant parts showing an example of a casing molded using the molding material of the embodiment of the present invention. It is. 1 is a front view showing a casing of a mobile phone molded using the molding material of Example 1. FIG. It is the figure which showed the relationship between the addition amount of glass fiber, and a bending elastic modulus. It is the figure which showed the relationship between the addition amount of a calcium silicate fiber, and a mold shrinkage rate. It is the figure which showed the relationship between the addition amount of an elastomer, and an Izod impact value.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material resin 2 Fibrous filler 3 Housing | casing 3a Thin part 3b Thick part 3c Cavity part 4a, 4b Shrinkage direction 5a, 5b Sink 6 Base material resin 7 Long fibrous filler 8 Short fibrous filler 9 Elastomer 10 Case 10a Thin portion 10b Thick portion 10c Hollow portions 11a, 11b Shrinkage directions 12a, 12b Resistance 13 Mobile phone 14 Case sample

Claims (5)

A molding material for an electronic device casing containing a base material resin, a filler, and a thermoplastic elastomer,
The base material resin includes polyamide and polyphenylene ether,
The filler includes a first fibrous filler and a second fibrous filler,
The molding material for an electronic device casing, wherein the aspect ratio of the second fibrous filler is smaller than the aspect ratio of the first fibrous filler.   2. The molding material for an electronic device casing according to claim 1, wherein the first fibrous filler is at least one selected from glass fibers and carbon fibers.   2. The molding material for an electronic device casing according to claim 1, wherein the second fibrous filler is at least one selected from calcium silicate, potassium titanate, and aluminum borate.   The molding material for an electronic device casing according to claim 1, wherein the thermoplastic elastomer is at least one selected from a styrene elastomer and an olefin elastomer. The electronic device housing which shape | molded the molding material for electronic device housings in any one of Claims 1-4.

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