Resin member for electronic device, resin composition and electronic device

Abstract

To provide a resin member for electronic device which is excellent in electric characteristics.SOLUTION: A resin member for an electronic device contains a matrix resin 1, and dielectric particles dispersed in the matrix resin 1, wherein the dielectric particles are aggregate particles 3 which are aggregates of ferroelectric particles 2, the particle size of the ferroelectric particles 2 is 10 nm or more and 1,000 nm or less, and the particle size of the aggregate particles 3 is 1 μm or more and 100 μm or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a resin member for electronic devices, a resin composition, and an electronic device.

Background Art

[0002] For the resin composition used for resin members for electronic devices, high dielectric constant and moldability are required. Patent Document 1 discloses a resin composition in which barium titanate, which is a ferroelectric with a particle size of about several μm and a high sphericity, is contained in a polycarbonate resin.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a dielectric with a high dielectric constant such as a ferroelectric and a normal dielectric with a relative dielectric constant of 10 or more is dispersed in a matrix resin, the dielectric particles near the surface are polarized by friction or the like, resulting in the surface of the resin member for electronic devices being charged and dust being likely to adhere. In particular, when relatively large particles with a particle diameter of 1 μm or more are used, the charge amount on the surface tends to increase, and when used for a resin member for electronic devices, there is a problem that dust is likely to adhere. An object of the present invention is to provide a resin member for electronic devices having excellent electrical characteristics.

Means for Solving the Problems

[0005] The resin member of the present invention is a resin member for electronic devices, including a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of ferroelectric particles The particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less. Another resin member of the present invention is a resin member for electronic equipment, including a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of normal dielectric particles having a relative permittivity of 10 or more, the particle diameter of the normal dielectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less. The resin composition of the present invention is a resin composition, including a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of ferroelectric particles, the particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less. The matrix resin is characterized by containing polyester and carbodiimide. Another resin composition of the present invention is a resin composition, including a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of normal dielectric particles having a relative permittivity of 10 or more, the particle diameter of the normal dielectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less. The matrix resin is characterized by containing polyester and carbodiimide.

Advantages of the Invention

[0006] According to the present invention, a resin member for an electronic device excellent in electrical characteristics can be provided.

Brief Description of Drawings

[0007]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments for carrying out the present invention will be described in detail. The following embodiments for carrying out the present invention are examples for explaining the present invention, and the present invention is not limited to the following contents.

[0009] ≪Resin Member for Electronic Device≫ The resin member for a first electronic device according to the present embodiment is a resin member including a matrix resin and dielectric particles dispersed in the matrix resin. And the dielectric particles are aggregate particles which are aggregates of ferroelectric particles. The particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less. The particle diameter of the aggregate particles is 1 μm or more and 100 μm or less.

[0010] Also, the resin member for a second electronic device according to the present embodiment is a resin member including a matrix resin and dielectric particles dispersed in the matrix resin. And the dielectric particles are aggregate particles which are aggregates of normal dielectric particles having a relative permittivity of 10 or more. The particle diameter of the normal dielectric particles is 10 nm or more and 1,000 nm or less. The particle diameter of the aggregate particles is 1 μm or more and 100 μm or less.

[0011] When there is friction between a resin member for an electronic device and another member, electron exchange occurs between them. The side that transfers electrons becomes positively charged, and the side that receives electrons becomes negatively charged, resulting in a so-called charged state. Ferroelectrics and normal dielectrics with a relative permittivity of 10 or more (hereinafter, both may be collectively referred to as "dielectrics" in some cases). In particular, ferroelectrics have a strong property of polarizing and retaining charges inside them. Therefore, when a dielectric is included in the material of the resin member for an electronic device, the amount of charge becomes large, and dust is likely to adhere.

[0012] FIG. 1 is a conceptual diagram showing a state in which dielectric particles are dispersed in a matrix resin. FIG. 1(a) shows a state in which primary particles of a dielectric with a relatively large particle diameter are dispersed, and FIG. 1(b) shows a state in which primary particles of a dielectric with a relatively small particle diameter are aggregated and dispersed as aggregate particles (secondary particles) with approximately the same particle diameter as the particles in FIG. 1(a). In FIG. 1, 1 is a matrix resin, 2 is a primary particle of a dielectric, and 3 is an aggregate particle.

[0013] FIG. 2 is a conceptual diagram showing a state in which the primary particles 2 of the dielectric are polarized in FIG. 1. FIG. 2(a) shows a state in which the primary particles 2 of the dielectric are polarized in FIG. 1(a), and FIG. 2(b) shows a state in which the primary particles 2 of the dielectric are polarized in FIG. 1(b). In FIG. 2, the charged state of the primary particles 2 of the dielectric is shown by shading.

[0014] When the particle diameter of the primary particles 2 of the dielectric is relatively large as shown in FIG. 1(a), the charge amount per particle increases in proportion to the volume of the particles. And because these primary particles 2 of the dielectric are dispersed in the matrix resin 1 and are near the surface of the resin member for an electronic device, the charge amount on the surface of the resin member for an electronic device increases, and the amount of dust adhesion increases.

[0015] In contrast, in the present embodiment, the dielectric particles in the resin member for an electronic device are such that the primary particles 2 of the dielectric having a relatively small particle diameter aggregate as shown in FIG. 1(b) to form aggregate particles 3. In this case, compared with the primary particles 2 of the dielectric having a particle diameter approximately the same as that of the aggregate particles 3, the amount of charge on the surface of the resin member for an electronic device becomes smaller, and the amount of dust adhesion is suppressed.

[0016] This can be considered as follows. That is, in the case of the primary particles having a relatively large particle diameter as shown in FIG. 1(a), as shown in FIG. 2(a), polarization occurs throughout the entire particle, resulting in a large amount of charge. On the other hand, when the primary particles having a relatively small particle diameter aggregate as shown in FIG. 1(b) to form aggregate particles having a large particle diameter, as shown in FIG. 2(b), it becomes an aggregate of polarized particles within individual primary particles. Therefore, only the primary particles exposed on the surface of the resin member for an electronic device affect the amount of charge on the surface. As a result, in the present embodiment, it is considered that the amount of dust adhesion is suppressed. Chargeability is one of the electrical characteristics of the resin member and can be controlled by the form of the dielectric particles.

[0017] Further, since the dielectric particles are in an aggregated state and the aggregate particles have a particle diameter of a certain size or more, the area of the interface between the matrix resin and the dielectric particles does not become excessively large, and the increase in viscosity is kept low, so that the moldability is also kept in a good state.

[0018] Furthermore, the aggregate particles are more advantageous for electromagnetic shielding properties. There is a parameter called dielectric tangent as an index related to electromagnetic shielding properties. In the case of FIG. 1(b), compared with the case of FIG. 1(a), the dielectric tangent becomes higher. The dielectric tangent is a parameter representing the amount of heat converted and lost when radio waves resonate with the dielectric. The larger this value is, the better the electromagnetic shielding properties. Electromagnetic shielding properties are one of the electrical characteristics of the resin member and can be controlled by the form of the dielectric particles.

[0019] ≪Method for manufacturing a resin member for an electronic device≫ <Resin composition> First, a resin composition that can be used for manufacturing a resin member for an electronic device according to this embodiment will be described. The resin composition according to this embodiment includes a matrix resin and dielectric particles. The resin composition according to this embodiment may further include an elastomer and may include filler particles mainly composed of an inorganic material other than the dielectric particles.

[0020] [Matrix Resin] The matrix resin may be a polymer having a repeating structure, and examples of the matrix resin include thermoplastic resins and thermosetting resins. Among them, thermoplastic resins are preferred as the matrix resin.

[0021] Examples of the thermoplastic resin include polyethylene, polystyrene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethersulfone, acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene resin, acrylic resin, polycarbonate, polyetherimide, polyetheretherketone, polyacetal, polyphenylene oxide, polyphenylene sulfide, and the like.

[0022] Examples of the thermosetting resin include epoxy resin, unsaturated polyester resin, vinyl ester resin, and the like.

[0023] The matrix resin is preferably a polar polymer. A polar polymer is a resin having polarization within the molecule, which can be oriented in the direction opposite to the polarization of the dielectric particles and can relax the charging.

[0024] The polar polymer is, for example, a polymer containing polar groups such as an amide group, an imide group, a carbonyl group (ketone group), and an ester bond in the main chain. Polar polymers are generally resins referred to as general-purpose engineering plastics and super engineering plastics, and are used in applications that require higher physical properties such as heat resistance and strength than general-purpose resins such as polyethylene and polypropylene. Also, if it is possible to improve the mechanical property values, it becomes possible to reduce the thickness and weight of the molded product, so further improvement of the physical properties of the polar polymer is expected.

[0025] Specific examples of the polar polymer include polymers having an amide group, such as polyamide and polyamideimide. Examples of the polymer having an imide group include polyimide, polyamideimide, and polyetherimide. Examples of the polymer having a carbonyl group (ketone group) include polyether ketone and polyether ether ketone. Examples of the polymer having an ester bond include polyarylate, polycarbonate, and polyester. Examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate.

[0026] As the matrix resin, it is preferable to use a crystalline polymer among thermoplastic resins. Since the molecules of the crystalline polymer are oriented in a specific direction, the polarization within the molecules is larger than that in the amorphous state, so that the polarization of the dielectric particles can be relaxed. In addition, the crystalline polymer is advantageous in that it is superior in hardness, elasticity, and rigidity compared to the amorphous polymer. Among the above-described polar polymers, examples of the crystalline polymer include polyamide, polyether ketone, polyether ether ketone, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate. Among the polyesters, polyarylate and polycarbonate are amorphous polymers. As the polar polymer, polyester is preferable, and polyethylene terephthalate is more preferable. Polyethylene terephthalate is both a polar polymer and a crystalline polymer, and since the orientation of the molecules easily occurs, the polarization of the dielectric particles can be more effectively relaxed. In addition, since the CO2 emission amount during the production of polyethylene terephthalate is smaller than that during the production of polycarbonate, the use of polyethylene terephthalate can contribute to the reduction of CO2 emissions. The crystallinity of the crystalline polymer is, for example, 1 to 50%, preferably 1 to 40%. The crystallinity can be controlled by the molding conditions (temperature and pressure).

[0027] Further, the matrix resin may be a polar polymer crosslinked using a crosslinking agent. Examples of the crosslinking agent include compounds that undergo a crosslinking reaction by heat, such as carbodiimide crosslinking agents, oxazoline crosslinking agents, epoxy-based crosslinking agents, and isocyanate crosslinking agents. The polar polymer may be, for example, a recycled polymer in which a used polymer with a reduced molecular weight is recovered and the used polymer is re-crosslinked with a crosslinking agent to increase the molecular weight. As the used polymer and the recycled polymer, polyethylene terephthalate, which has a large production volume and usage amount, is preferable.

[0028] The carbodiimide crosslinking agent in the present embodiment is a compound having at least one carbodiimide group in the molecule, and can be produced, for example, by heating an organic isocyanate in the presence of a suitable catalyst and performing a decarboxylation reaction. The carbodiimide group is represented by (-N=C=N-). In the matrix resin using the carbodiimide crosslinking agent, the carbodiimide group derived from the carbodiimide crosslinking agent exists as a part of the polymer.

[0029] Examples of carbodiimide crosslinking agents include, for example, diphenylcarbodiimide, dicyclohexylcarbodiimide, di-2,6-dimethylphenylcarbodiimide, diisopropylcarbodiimide, dioctyldecylcarbodiimide, di-o-tolylcarbodiimide, di-p-tolylcarbodiimide, di-p-nitrophenylcarbodiimide, di-p-aminophenylcarbodiimide, di-p-hydroxyphenylcarbodiimide, di-p-chlorophenylcarbodiimide, di-o-chlorophenylcarbodiimide, di-3,4-dichlorophenylcarbodiimide, di-2,5-dichlorophenylcarbodiimide, p-phenylene-bis-o-tolylcarbodiimide, p-phenylene-bis-dicyclohexylcarbodiimide, p-phenylene-bis-di-p-chlorophenylcarbodiimide, 2,6,2’,6’-tetraisopropyldiphenylcarbodiimide, hexamethylene-bis-cyclohexylcarbodiimide, ethylene-bis-diphenylcarbodiimide, ethylene-bis-dicyclohexylcarbodiimide, N,N’-di-o-tolylcarbodiimide, N,N’-diphenylcarbodiimide, N,N’-dioctyldecylcarbodiimide, N,N’-di-2,6-dimethylphenylcarbodiimide, N-tolyl-N’-cyclohexylcarbodiimide, N,N’-di-2,6-diisopropylphenylcarbodiimide, N,N’-di-2,6-di-tert-butylphenylcarbodiimide, N-tolyl-N’-phenylcarbodiimide, N,N’-di-p-nitrophenylcarbodiimide, N,N’-di-p-aminophenylcarbodiimide, N,N’-di-p-hydroxyphenylcarbodiimide, N,N’-dicyclohexylcarbodiimide, N,N’-di-p-tolylcarbodiimide, N,N’-benzylcarbodiimide, N-octadecyl-N’-phenylcarbodiimide, N-benzyl-N’-phenylcarbodiimide, N-octadecyl-N’-tolylcarbodiimide, N-cyclohexyl-N’-tolylcarbodiimide, N-phenyl-N’-tolylcarbodiimide, N-benzyl-N’-tolylcarbodiimide, N,N’-di-o-ethylphenylcarbodiimide, N,N’-di-p-ethylphenylcarbodiimide, N,Mono- or dicarbodiimide compounds such as N'-di-o-isopropylphenylcarbodiimide, N,N'-di-p-isopropylphenylcarbodiimide, N,N'-di-o-isobutylphenylcarbodiimide, N,N'-di-p-isobutylphenylcarbodiimide, N,N'-di-2,6-diethylphenylcarbodiimide, N,N'-di-2-ethyl-6-isopropylphenylcarbodiimide, N,N'-di-2-isobutyl-6-isopropylphenylcarbodiimide, N,N'-di-2,4,6-trimethylphenylcarbodiimide, N,N'-di-2,4,6-triisopropylphenylcarbodiimide, N,N'-di-2,4,6-triisobutylphenylcarbodiimide; polycarbodiimides such as poly(1,6-hexamethylene carbodiimide), poly(4,4'-methylenebiscyclohexyl carbodiimide), poly(1,3-cyclohexylene carbodiimide), poly(1,4-cyclohexylene carbodiimide), poly(4,4'-diphenylmethane carbodiimide), poly(3,3'-dimethyl-4,4'-diphenylmethane carbodiimide), poly(naphthylene carbodiimide), poly(p-phenylene carbodiimide), poly(m-phenylene carbodiimide), poly(tolyl carbodiimide), poly(diisopropyl carbodiimide), poly(methyl-diisopropylphenylene carbodiimide), poly(triethylphenylene carbodiimide), poly(triisopropylphenylene carbodiimide), etc. are mentioned.,

[0030] The oxazoline crosslinking agent in this embodiment is a compound having an oxazoline group in the molecule. In particular, a polymer synthesized using a monomer containing an oxazoline compound as at least one of its raw material monomers is preferred. Examples of the oxazoline compound include 2-oxazoline, 3-oxazoline, and 4-oxazoline compounds, and any of them may be used. In particular, the 2-oxazoline compound is rich in reactivity and has been put into practical use industrially. Examples of the oxazoline compound include 2-vinyl-2-oxazoline, 5-methyl-2-vinyl-2-oxazoline, 4,4-oxazoline, 4,4-dimethyl-2-vinyl-5,6-dihydro-4H-1,3-oxazine, 4,4,6-trimethyl-2-vinyl-5,6-dihydro-4H-1,3-oxazine, 2-isopropenyl-2-oxazoline, 4,4-dimethyl-2-isopropenyl-2-oxazoline, 4-acryloyl-oxymethyl-2,4-dimethyl-2-oxazoline, 4-methacryloyl-oxymethyl-2,4-dimethyl-2-oxazoline, 4-methacryloyl-oxysimethyl-2-phenyl-4-methyl-2-oxazoline, 2-(4-vinylphenyl)-4,4-dimethyl-2-oxazoline, 4-ethyl-4-hydroxymethyl-2-isopropenyl-2-oxazoline, 4-ethyl-4-carboethoxymethyl-2-isopropenyl-2-oxazoline, etc., but are not limited thereto.

[0031] In the epoxy-based crosslinking agent in this embodiment, for example, glycidyl ether compounds, glycidyl ester compounds, glycidyl amine compounds, glycidyl imide compounds, alicyclic epoxy compounds, etc. can be preferably used.

[0032] Examples of glycidyl ether compounds include, for example, butyl glycidyl ether, stearyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, o-phenylphenyl glycidyl ether, ethylene oxide lauryl alcohol glycidyl ether, ethylene oxide phenol glycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol polyglycidyl ether, bisphenol A diglycidyl ether type epoxy resins, bisphenol F diglycidyl ether type epoxy resins, bisphenol S diglycidyl ether type epoxy resins, etc. obtained from the condensation reaction of bisphenols such as 2,2-bis-(4-hydroxyphenyl)propane, 2,2-bis-(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)sulfone and epichlorohydrin. Among them, bisphenol A diglycidyl ether type epoxy resins are preferred.

[0033] Examples of glycidyl ester compounds include, for example, glycidyl benzoate, glycidyl p-toluate, glycidyl cyclohexanecarboxylate, glycidyl stearate, glycidyl laurate, glycidyl palmitate, glycidyl versatate, glycidyl oleate, glycidyl linoleate, glycidyl linolenate, diglycidyl terephthalate, diglycidyl isophthalate, diglycidyl phthalate, diglycidyl naphthalenedicarboxylate, diglycidyl bibenzoate, diglycidyl methylterephthalate, diglycidyl hexahydrophthalate, diglycidyl tetrahydrophthalate, diglycidyl cyclohexanedicarboxylate, diglycidyl adipate, diglycidyl succinate, diglycidyl sebacate, diglycidyl dodecanedioate, diglycidyl octadecanedicarboxylate, triglycidyl trimellitate, tetraglycidyl pyromellitate and the like. Among them, glycidyl benzoate and glycidyl versatate are preferred.

[0034] Examples of glycidylamine compounds include, for example, tetraglycidylaminodiphenylmethane, triglycidyl - para - aminophenol, triglycidyl - meta - aminophenol, diglycidylaniline, diglycidyltoluidine, tetraglycidylmetaxylenediamine, diglycidyltribromoaniline, tetraglycidylbisaminomethylcyclohexane, triglycidyl cyanurate, triglycidyl isocyanurate, and the like. Examples of glycidylimide compounds include N - glycidylphthalimide, N - glycidyl - 4 - methylphthalimide, N - glycidyl - 4,5 - dimethylphthalimide, N - glycidyl - 3 - methylphthalimide, N - glycidyl - 3,6 - dimethylphthalimide, N - glycidyl - 4 - ethoxyphthalimide, N - glycidyl - 4 - chlorophthalimide, N - glycidyl - 4,5 - dichlorophthalimide, N - glycidyl - 3,4,5,6 - tetrabromophthalimide, N - glycidyl - 4 - n - butyl - 5 - bromophthalimide, N - glycidylsuccinimide, N - glycidylhexahydrophthalimide, N - glycidyl - 1,2,3,6 - tetrahydrophthalimide, N - glycidylmaleimide, N - glycidyl - α,β - dimethylsuccinimide, N - glycidyl - α - ethylsuccinimide, N - glycidyl - α - propylsuccinimide, N - glycidylbenzamide, N - glycidyl - p - methylbenzamide, N - glycidylnaphthamide, N - glycidylstearamide, and the like. Among them, N - glycidylphthalimide is preferred.

[0035] Examples of alicyclic epoxy compounds include, for example, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexyl carboxylate, bis(3,4-epoxycyclohexylmethyl) adipate, vinylcyclohexene diepoxide, N-methyl-4,5-epoxycyclohexane-1,2-dicarboximide, N-ethyl-4,5-epoxycyclohexane-1,2-dicarboximide, N-phenyl-4,5-epoxycyclohexane-1,2-dicarboximide, N-naphthyl-4,5-epoxycyclohexane-1,2-dicarboximide, N-tolyl-3-methyl-4,5-epoxycyclohexane-1,2-dicarboximide, and the like.

[0036] In addition, as other epoxy compounds, epoxy-modified fatty acid glycerides such as epoxidized soybean oil, epoxidized linseed oil, and epoxidized whale oil, phenol novolac type epoxy resins, cresol novolac type epoxy resins, and the like can be used.

[0037] Regarding the isocyanate crosslinking agent used in this embodiment, it is not particularly limited as long as the compound has an isocyanate group as a functional group, and a known polyisocyanate crosslinking agent can be used. Specifically, a generally used water-dispersible polyisocyanate-based crosslinking agent can be used. The water-dispersible polyisocyanate-based crosslinking agent is obtained by introducing a hydrophilic group into a polyisocyanate polymer, and when added to and stirred in water, it can be dispersed in water as fine particles.

[0038] Examples of the polyisocyanate constituting the water-dispersible polyisocyanate include aliphatic isocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, lysine diisocyanate, and dimer acid diisocyanate; aromatic polyisocyanates such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, 1,4-naphthalene diisocyanate, 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether isocyanate, (m- or p-) phenylene diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-biphenylene diisocyanate, bis(4-isocyanatophenyl) sulfone, and isopropylidene bis(4-phenyl isocyanate); and alicyclic diisocyanate compounds such as hydrogenated xylylene diisocyanate, isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), methylcyclohexane-2,4-(or -2,6-) diisocyanate, 1,3-(or 1,4-) di(isocyanatomethyl) cyclohexane, 1,4-cyclohexane diisocyanate, 1,3-cyclopentane diisocyanate, and 1,2-cyclohexane diisocyanate. As such polyisocyanate compounds, polyisocyanate compounds having an isocyanurate structure, a urethane structure, a biuret structure, an allophanate structure, a uretdione structure, a trimer structure, etc. can also be used. A so-called blocked isocyanate in which an isocyanate group is blocked with an active hydrogen group may also be used.

[0039] The matrix resin is preferably formed from one of these polar polymers or a mixture thereof.

[0040] [Dielectric (ferroelectric and normal dielectric with a relative permittivity of 10 or more)] The ferroelectric material is not particularly limited as long as it exhibits ferroelectricity. Ferroelectric materials typically have a perovskite structure, but may also be tetragonal or rhombohedral (rhombohedral). Examples of ferroelectric materials include titanate compounds such as barium titanate, bismuth titanate, lead titanate, lead zirconate titanate, and lead lanthanum zirconate titanate; bismuth ferrite (bismuth ferrite); strontium bismuth tantalate; and strontium bismuth niobate. Also, those in which titanium in the titanate compound is substituted with group IV elements such as Hf and Zr, or those in which Ba in barium titanate is substituted with group II elements such as Ca and Sr may be used. It is also known that orthorhombic hafnium oxide exhibits ferroelectricity. Among these, titanate compounds are preferred because of their high relative permittivity, and barium titanate is even more preferred. The ferroelectric material may be used alone or in an appropriate mixture of two or more types.

[0041] In addition, the ferroelectric particles may have a core-shell structure having two phases: a core portion composed of a crystal with a high dielectric constant and a shell portion with a relatively low dielectric constant surrounding the core portion. For example, the ferroelectric particles may have a core-shell structure having a core portion composed of barium titanate crystals and a shell portion containing rare earth elements such as dysprosium (Dy) and holmium (Ho).

[0042] Examples of normal dielectrics having a relative permittivity of 10 or more include titanium oxide (titania), zirconium oxide (zirconia), hafnium oxide (hafnia), yttrium oxide (yttria), lanthanum oxide, cerium oxide (ceria), tantalum oxide, niobium oxide, zinc titanate, magnesium titanate, strontium titanate, calcium titanate, and calcium zirconate. The relative permittivity of the normal dielectric is preferably 50 or more, more preferably 100 or more, still more preferably 500 or more, and even more preferably 1,000 or more.

[0043] The particle diameter (primary particle diameter) of the ferroelectric particles (primary particles) and the paraelectric particles (primary particles) with a relative permittivity of 10 or more is preferably 10 nm or more and 1,000 nm or less. When the particle diameter of the primary particles of the dielectric is larger than 1,000 nm, the amount of charge inside the particles increases, and the amount of charge on the surface of the resin member for electronic devices increases. Therefore, the particle diameter of the primary particles of the dielectric is preferably 1,000 nm or less. When the particle diameter of the primary particles of the dielectric is 300 nm or less, the amount of charge decreases, so the adhesion of dust is further suppressed, which is more preferable. Also, when the particle diameter of the primary particles of the dielectric is smaller than 10 nm, the cohesive force between the particles increases. When forming aggregate particles, charge exchange occurs between the particles, and the amount of charge of the entire aggregate particles increases, resulting in an increase in the amount of charge on the surface of the resin member for electronic devices. Therefore, the particle diameter of the primary particles of the dielectric is preferably 10 nm or more. When the particle diameter of the primary particles of the dielectric is 50 nm or more, the cohesive force between the particles decreases, and the controllability of the particle size increases, which is more preferable.

[0044] The dielectric is preferably in an aggregated state. Further, the particle diameter (secondary particle diameter) of the aggregate particles (secondary particles) is preferably 1 μm or more and 100 μm or less. When the particle diameter of the aggregate particles is less than 1 μm, the surface area of the aggregate particles increases, the area of the interface with the matrix resin increases, the melt viscosity increases, and good moldability cannot be obtained. Therefore, the particle diameter of the aggregate particles is preferably 1 μm or more. When the particle diameter of the aggregate particles is 5 μm or more, better fluidity can be obtained, which is more preferable. Also, when the particle diameter of the aggregate particles is 5 μm or more, the charges interfere with each other complicatedly between the dielectric particles in the aggregate particles, so the dielectric loss tangent increases and the electromagnetic shielding property becomes even better, which is more preferable. On the other hand, when the particle diameter of the aggregate particles is larger than 100 μm, the surface property deteriorates due to the influence of the aggregate particles, and good moldability cannot be obtained. For this reason, the particle diameter of the aggregate particles is preferably 100 μm or less. When the particle diameter of the aggregate particles is 50 μm or less, the surface property becomes even better, which is more preferable.

[0045] The shape of the aggregate particles is not particularly limited, but it is preferably flaky. When the shape of the aggregate particles is flaky, the aggregate particles function as a nucleating agent or a crystallization accelerator, and the crystallization of the matrix resin is promoted around the aggregate particles. As a result, in the resin member for electronic devices, there are portions where crystallization is promoted and portions where crystallization is not promoted. Since the elastic modulus of the portion where crystallization is promoted and the portion where crystallization is not promoted is different, when a small amount of aggregate particles are unevenly present, when vibration occurs, it deforms unevenly, and energy loss due to shear friction occurs, improving the vibration damping property.

[0046] The aspect ratio of the aggregate particles is preferably 3 or more and 20 or less. If the aspect ratio of the aggregate particles is less than 3, the aggregate particles may be likely to be exposed on the surface during molding, so the surface charge amount may increase. Furthermore, since the surface charge amount decreases, the aspect ratio of the aggregate particles is preferably 5 or more. On the other hand, if the aspect ratio of the aggregate particles exceeds 20, the surface property may deteriorate due to the influence of the aggregate particles, so it may not be possible to obtain good moldability. Furthermore, since the surface property improves, the aspect ratio of the aggregate particles is preferably 10 or less.

[0047] The number of aggregate particles per unit area is 1 particle / mm 2 or more and 100 particles / mm 2 or less is preferred. If the number of aggregate particles per unit area is less than 1 particle / mm 2 , the dielectric loss tangent may decrease. On the other hand, if the number of aggregate particles per unit area exceeds 100 particles / mm 2 , there may be more dielectric particles near the surface and the surface charge may increase, so the adsorption of dust may increase.

[0048] Examples of the measurement methods for the particle diameter of the primary particles of the dielectric, the particle diameter of the aggregate particles, the aspect ratio of the aggregate particles, and the number of aggregate particles include the following methods.

[0049] That is, for the resin member for an electronic device of the present embodiment, a transverse cross-section sample is produced by pretreatment such as cross-section polishing, microtome, ion milling, etc. Ion milling is suitable because it has high cross-section smoothness and can suppress particle dropout. When the temperature of the sample rises due to processing, cooling such as cryogenic treatment may be performed.

[0050] Thereafter, observation is performed by a scanning electron microscope (SEM) under the conditions shown below, and an SEM image of the cross-section is obtained. Note that it is preferable to properly select the observation magnification according to the particle diameter. For example, when the particle diameter is 100 nm or less, observation is performed at a magnification of 50,000 times, when the particle diameter exceeds 100 nm, observation is performed at a magnification of 10,000 times, and when the particle diameter further exceeds 10 μm, it is preferable to perform observation at a magnification of 1,000 times.

[0051] From the obtained SEM image, the median diameter of the dielectric particles in an arbitrary range of the cross-section of the resin member for an electronic device is taken as the particle diameter of the dielectric particles by binarization and image analysis under the conditions shown below. An arbitrary range of the cross-section of the resin member for an electronic device can be, for example, a quadrilateral region where the lengths of two adjacent sides are length L and length M. The length L and the length M are, for example, 5 μm or more, preferably 10 μm or more, for example 500 μm or less, and for example 100 μm or less. The length L and the length M may be the same or different, and the ratio of the length L to the length M may be 0.5 or more and 2 or less. Note that binarization and image analysis of the SEM image use the image processing software ImageJ (available from https: / / imagej.nih.gov / ij / ) of the National Institutes of Health, USA.

[0052] [Conditions] {Device name} Schottky field emission type scanning electron microscope JSM-F100 (manufactured by JEOL Ltd.) {Acceleration voltage} 3 kV {Magnification} 10,000 times or 1,000 times {Measurement range} 12.8 μm × 9.6 μm (10,000 times) or 128 μm × 96 μm (1,000 times) {Number of evaluations} 10 areas / sample {Binarization and image analysis} ImageJ {Binarization method} MaxEntropy (The threshold value should be appropriately adjusted so that the dielectric particles can be separated by binarization. If binarization cannot be performed by image processing software, prepare an image in which only the dielectric particles are filled in visually using a separate painting software etc.) {Calculation method of particle size} The length at the position where the particle size of the aggregate particles is the maximum is defined as the major axis, and the length at the position where the length is the maximum in the direction orthogonal to this major axis is defined as the minor axis. The particle size of each particle was (major axis + minor axis) / 2. As the representative value (statistical value) of the particle size, the median (median diameter; 50% particle size) was used. In addition, as the representative value of the particle size, the average value (average particle size) or the mode value (mode diameter) can also be used. {Calculation method of aspect ratio} Major axis / minor axis (mass average value) {Calculation method of the number of aggregate particles per unit area} From the binarized image, a group of primary particles of the contacted dielectric was judged as one aggregate particle, the number of aggregate particles was measured from the observation image, and the value obtained by dividing by the observation area was defined as the number of aggregate particles per unit area.

[0053] The content of the dielectric particles is preferably 0.1 mass% or more and 30 mass% or less. If the content of the dielectric particles is less than 0.1 mass%, the dielectric tangent is low and it may be difficult to exhibit electromagnetic shielding properties. If the content of the dielectric particles is 1 mass% or more, the dielectric tangent increases and better electromagnetic shielding properties are exhibited, which is more preferable. On the other hand, if the content of the dielectric particles is more than 30 mass%, there may be an increase in the number of dielectric particles near the surface, resulting in an increase in surface charge and a possible increase in dust adsorption. If the content of the dielectric particles is 10 mass% or less, the amount of dust adsorption decreases, which is more preferable.

[0054] [Elastomer Material] It is known that the addition of an elastomer material to a resin improves the impact strength. Therefore, in this embodiment, an elastomer material may be contained for further improvement of the impact strength. The content of the elastomer material is preferably 30% by mass or less. The elastomer material is a copolymer composed of a hard segment that serves as a crosslinking point and a soft segment that exhibits rubber elasticity, and a thermoplastic elastomer having both the properties of plastic and rubber is preferred.

[0055] Examples of the elastomer material include urethane-based elastomers, ester-based elastomers, amide-based elastomers, acrylic-based elastomers, olefin-based elastomers, styrene-based elastomers, etc. The elastomer material is preferably an acrylic-based elastomer or an ester-based elastomer.

[0056] Examples of the urethane-based elastomer include an elastomer in which the hard segment is a polyurethane containing a urethane group and the soft segment is a polyester containing an ester bond or a polyether containing an ether bond. Note that the urethane group and the ester bond have polarity.

[0057] Examples of the ester-based elastomer include an elastomer in which the hard segment is a polyester containing an ester bond and the soft segment is a polyester containing an ester bond or a polyether containing an ether bond. Note that the ester bond has polarity.

[0058] Examples of the amide-based elastomer include an elastomer in which the hard segment is a polyamide containing an amide group and the soft segment is a polyester containing an ester bond or a polyether containing an ether bond. Note that the amide group and the ester bond have polarity.

[0059] Examples of acrylic elastomers include those in which the hard segment is polymethyl methacrylate which is a polymer of methyl methacrylate and has an ester bond, and the soft segment is an elastomer which is a copolymer of butyl acrylate, 2-ethylhexyl acrylate, etc. having an ester bond. Further, examples include elastomers in which the hard segment is a polyolefin such as polyethylene and the soft segment is polymethyl methacrylate which is a polymer of methyl methacrylate and has an ester bond. Note that the ester bond has polarity.

[0060] Examples of olefin-based elastomers include those in which the hard segment is a polyolefin such as polypropylene or polyethylene, and the soft segment is an elastomer such as ethylene propylene rubber or ethylene propylene diene rubber.

[0061] Examples of styrene-based elastomers include those in which the hard segment is polystyrene and the soft segment is butadiene, isoprene, ethylene, etc.

[0062] When the matrix resin is a polar polymer, from the viewpoint of affinity with the matrix resin, the elastomer material preferably has a polar group. The polar group possessed by the elastomer material is, for example, a urethane group, an amide group, an ester bond, etc. In particular, it is preferable that the elastomer material has an ester bond in either or both of the hard segment and the soft segment.

[0063] Since the elastomer material has a polar group such as an ester bond, the elastomer material has heat resistance and can be melt-kneaded with a polar polymer, particularly a polar polymer having high heat resistance. Further, the elastomer material having an ester bond has relatively high mechanical properties and contributes to the improvement of physical properties.

[0064] Since the glass transition point (glass transition temperature) of the elastomer material is lower than room temperature, it acts as an elastomer at room temperature. The glass transition point of the elastomer material is preferably lower than 0 °C, and more preferably -20 °C or lower.

[0065] By melt-kneading the elastomer material with a matrix resin that is a thermoplastic resin in a molten state and finely dispersing it as elastomer particles in the matrix resin, the impact strength is improved. Therefore, the melting point of the elastomer material is preferably lower than the heating temperature (molding temperature) of the resin composition so that it can be melt-kneaded with the matrix resin. The heating temperature of the resin composition is the temperature at which the matrix resin, which is a thermoplastic polymer, melts, and is preferably higher than the glass transition point of the matrix resin. If the matrix resin is a crystalline polymer, it is preferably higher than the melting point of the matrix resin. Therefore, the melting point of the elastomer material is preferably lower than the melting point of the matrix resin. Although the melting point of the elastomer material may be higher than the melting point of the matrix resin, this can cause thermal degradation such as a decrease in the molecular weight of the matrix resin due to heating of the matrix resin to melt the elastomer material. When the matrix resin is a crystalline polymer, the melting point of the elastomer material may be higher than the glass transition point of the matrix resin. When the matrix resin is an amorphous polymer, since the melting point of the matrix resin is not defined, the melting point of the elastomer material is preferably lower than the glass transition point of the matrix resin.

[0066] The glass transition point of the matrix resin is preferably 50 °C or higher to ensure strength during use, and also preferably 200 °C or lower in consideration of processability. The melting point of the matrix resin is preferably 100 °C or higher, preferably 200 °C or higher, and preferably 300 °C or lower in consideration of heat resistance and processability. The melting point of the elastomer material is preferably 50 °C or higher to ensure strength during use, preferably 300 °C or lower, and preferably 200 °C or lower in consideration of processability.

[0067] Since the elastomer material has rubber elasticity, i.e., flexibility, it contributes to improving the impact strength of the matrix resin. When an impact is applied to a molded article obtained by molding a resin composition containing an elastomer, the matrix resin is oriented around the elastomer particles, and crazes are formed, so that the impact can be more efficiently mitigated. Therefore, it is preferable that a large number of fine elastomer particles are dispersed. For this reason, the particle diameter of the elastomer particles is preferably 10 μm or less, more preferably 5 μm or less. In order for the elastomer particles to function mechanically efficiently, the particle diameter of the elastomer particles is preferably 0.1 μm or more, more preferably 0.5 μm or more. Elastomer particles are typically particles formed by dispersion mixing through melt kneading, and the particle diameter of such elastomer particles can be referred to as the dispersion particle diameter or the dispersion grain size. The particle diameter can be measured, for example, in the same manner as the particle diameter of dielectric particles.

[0068] [Filler particles] It is known that the addition of filler particles to a resin improves mechanical properties such as the flexural modulus. Therefore, in the present embodiment, in order to further improve the flexural modulus and impact strength, filler particles mainly composed of an inorganic material other than dielectric particles may be contained. The relative dielectric constant of the inorganic material is preferably less than 10. The content of the filler particles is preferably 40% by mass or less. The shape of the filler particles is spherical such as a true sphere or an oblate sphere, polyhedral, irregular, plate-like, scaly, needle-like or fibrous. The length of the needle-like or fibrous filler particles is, for example, 100 μm or less, preferably 30 μm or less, more preferably 10 μm or less.

[0069] The filler particles mainly composed of inorganic materials are not particularly limited. For example, there are particles such as mica, glass fiber, glass sphere, zinc oxide, calcium carbonate, clays, talc, silicon oxide (silica), wollastonite, forsterite, zeolite, diatomaceous earth, silica sand, fly ash, pumice powder, slate powder, aluminum oxide (alumina), alumina white, aluminum sulfate, carbon fiber, carbon nanotube, metal fiber, barium sulfate, calcium sulfate, molybdenum disulfide, shirasu balloon, fly ash balloon, etc.

[0070] The filler particles may have a substrate of an inorganic material that is the main component of the filler particles and a surface layer of an organic material or an inorganic material covering the substrate. The thickness of the surface layer is, for example, 100 nm or less, and preferably 10 nm or less. In the filler particles mainly composed of an inorganic material, the volume occupied by the inorganic material is preferably larger than the volume occupied by the organic material and is 90% by volume or more.

[0071] When an impact is applied to a molded body containing elastomer particles, the matrix resin is oriented around the elastomer particles and crazes are formed, so that the impact can be more efficiently mitigated. At this time, in order to avoid a decrease in impact strength due to the filler particles becoming material defects, the filler particles preferably have a small particle size. When the filler particles are coarse particles with a large particle size, the filler particles act as stress concentration points, so the impact strength decreases and cracks may propagate. On the other hand, in the resin composition manufacturing process, in order to sufficiently crush and disperse the particles, it is preferable to avoid poor dispersion due to particle aggregation caused by the small particle size. When the filler particles are fine particles with a small particle size, it may be difficult to disperse the filler particles due to particle aggregation in the resin composition manufacturing process. As a result, material defects due to particle aggregation may occur, leading to a decrease in impact strength and the possibility of crack propagation.

[0072] Therefore, the particle size of the independently dispersed filler particles is, for example, 10 μm or less, preferably 5 μm or less, and more preferably 2 μm or less. If the particle size of the filler particles is 10 μm or less, a decrease in impact strength due to the addition of the filler particles can be satisfactorily suppressed. Also, if the particle size is 0.2 μm or more, the filler particles can be satisfactorily finely dispersed in the matrix resin, and a decrease in impact strength can be suppressed. For this reason, it is preferable that the particle size of the filler particles is 0.2 μm or more and 10 μm or less, more preferably 0.2 μm or more and 5 μm or less, and even more preferably 0.2 μm or more and 2 μm or less. The resin composition may contain filler particles having a particle size exceeding 10 μm. The particle size of the filler particles exceeding 10 μm is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 30 μm or less. The particle size can be measured, for example, in the same manner as the particle size of the dielectric particles.

[0073] It is preferable that the surface of the filler particles is surface-treated with a surface treatment agent such as a coupling agent or a fatty acid. For the surface-treated filler particles, commercially available products that have been surface-treated in advance may be used, or a separate surface treatment step may be provided during the production of the resin composition. The amount of the surface treatment agent used can be calculated from the specific surface area of the filler particles to be treated and the minimum covering area of the surface treatment agent. When using filler particles with a small particle size, since the specific surface area of the filler particles increases, the amount of the surface treatment agent used inevitably increases. For this reason, there is a range in the addition amount of the surface treatment agent used, and it is common to add about 0.5% by mass to 5% by mass based on the filler particles. As the treatment method, known methods such as a dry treatment method such as an integral blend method or a wet treatment method using an aqueous solution of the surface treatment agent can be used. The surface layer formed by the surface treatment constitutes a part of the filler particles.

[0074] Examples of the surface treatment agent include silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, and 3-trimethoxysilylpropyl succinic anhydride. Also, titanate-based or aluminate-based coupling agents may be used. Examples of the fatty acid include lauric acid, stearic acid, and oleic acid. Among these, silane coupling agents are preferred. These surface treatment agents may be used alone or in combination of two or more.

[0075] [Other Components] In the resin composition of this embodiment, various other additives may be blended as necessary. The type of the additive is not particularly limited as long as it is generally used in the blending of thermoplastic resins and thermoplastic elastomer materials. As various additives for improving functionality, there are flame retardants, waxes, various fatty acids, fatty acid amides, fatty acid esters, lubricants and mold release agents such as metal salts of fatty acids, various antistatic agents, fatty acid esters, sliding property improvers such as polyolefins, olefin copolymer elastomers, and polysiloxanes, polymerizations of polyamide resins and acrylamide, amide compounds, amino-substituted triazine compounds and their derivatives, urea and its derivatives, hydrazine derivatives, imidazole compounds, imide compounds, epoxy compounds and other decomposition inhibitors, formic acid scavengers such as melamine, hydroxides and carbonates of alkali metals, and flame retardants such as organophosphorus compounds. Also, as various additives for improving long-term stability, there are ultraviolet absorbers such as benzotriazole-based compounds, benzophenone-based compounds, and phenyl salicylate compounds, hindered amine-based light stabilizers, hindered phenol-based antioxidants, and the like. The above additives may be used in combination of one or more.

[0076] The resin composition of the present embodiment may contain at least one of a metal material containing a transition metal element, a compound material containing a transition metal element, a metal material containing a typical metal element, and a compound material containing a typical metal element, other than dielectric particles.

[0077] Examples of the transition metal element include titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium (Nb), molybdenum (Mo), hafnium (Hf), tantalum (Ta), tungsten (W), palladium (Pd), platinum (Pt), silver (Ag), gold (Au), etc. Examples of the typical metal element include sodium (Na), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), zinc (Zn), aluminum (Al), gallium (Ga), germanium (Ge), indium (In), tin (Sn), antimony (Sb), etc. Note that silicon (Si) and arsenic (As) can be classified as semi-metals together with germanium (Ge) and antimony (Sb), but here, silicon (Si) and arsenic (As) are treated as non-metal elements. The metal material is a simple metal or an alloy, and the metal compound, which is a compound containing a metal element, is, for example, an oxide, nitride, carbide, inorganic acid salt, or organic acid salt of the metal element. The metal compound may be a composite compound containing a plurality of transition metal elements, a plurality of typical metal elements, or a transition metal element and a typical metal element. Compounds are classified into inorganic compounds and organic compounds, and the organic compound that is a metal compound, that is, an organometallic compound, is assumed to be a compound having a bond between carbon and a metal element.

[0078] The materials containing the transition metal elements and typical metal elements listed herein may be filler particles having a particle diameter of 0.1 μm or more dispersed in the matrix resin, or may be particles having a particle diameter of less than 0.1 μm. Further, when elastomer particles are included, the materials containing the transition metal elements and typical metal elements listed herein may be particles smaller than the elastomer particles, or may be particles in which the elastomer particles are dispersed. Alternatively, the materials containing the transition metal elements and typical metal elements listed herein may be dissolved in the matrix resin or the elastomer particles.

[0079] The content of the materials containing the transition metal elements and typical metal elements listed herein is preferably 0.01% by mass or more and 5% by mass or less, and less than the content of the matrix resin and the dielectric particles. Within this range, ferroelectric interaction may occur and the dielectric tangent may increase.

[0080] When the content of a specific metal element differs between the matrix resin and the elastomer material, by obtaining a distribution image (mapping image) of the metal element, the distinction between the matrix resin and the elastomer material in the observation image can be easily made. For example, aluminum (Al), germanium (Ge), antimony (Sb), or titanium (Ti) is contained in a compound as a polymerization catalyst when polymerizing a polar polymer and can be dissolved or dispersed in the matrix resin. Alternatively, the materials containing the transition metal elements and typical metal elements may be contained in a compound as a pigment for coloring the resin composition and can be dispersed in the matrix resin. Alternatively, a plurality of filler particles may include, for example, filler particles mainly composed of calcium carbonate and filler particles mainly composed of titanium oxide, and both of them may be independently dispersed.

[0081] <Manufacturing method of resin composition> The method for manufacturing the resin composition is not particularly limited, but it is preferable to aggregate the primary particles of the dielectric in advance to form aggregate particles. Specifically, for example, polyvinyl butyral, dioctyl phthalate, toluene, ethanol, etc. are added to the primary particles of the dielectric, and they are mixed and dispersed by a ball mill to prepare a dielectric slurry. Then, using an applicator or the like, the dielectric slurry is applied to a polyethylene terephthalate film or the like and dried to form a dielectric layer. The dielectric layer is peeled off using a squeegee or the like, and the peeled dielectric layer is pulverized using a ball mill or the like to obtain aggregate particles of the dielectric. At this time, for example, the particle diameter and aspect ratio of the aggregate particles can be adjusted by adjusting the pulverization time.

[0082] As means for mixing the matrix resin and the dielectric particles, for example, there is a method of melting the resin composition and applying shear using a screw or blades such as a twin-screw extruder or a kneader. Also, there is a method of melting and applying shear by passing the resin composition over a plurality of adjacent rolls like a roll mill. Further, the resin composition to which shear has been applied can be pelletized by finely cutting the continuously discharged strand, or can be taken out as a resin mass and pulverized by a pulverizer to be made finer. The method for manufacturing the resin composition of the present embodiment may include a step of melt-kneading the matrix resin and the dielectric particles. Examples of the kneading device include a twin-screw extruder, a two-roll mill, etc. Specifically, a TEM type extruder (manufactured by Toshiba Machine Co., Ltd.), a TEX twin-screw kneader (manufactured by Japan Steel Works, Ltd.), a PCM kneader (manufactured by Ikegai Iron Works Co., Ltd.), a Neodeck (manufactured by Nippon Coke Co., Ltd.), etc. can be mentioned.

[0083] <Forming method> The forming method is not particularly limited. For example, there are injection molding, extrusion molding, press molding, transfer molding, etc. Injection molding may be performed using pellets manufactured by extrusion molding from a mold. Among these, injection molding in which the resin composition is melted and injected into a mold is preferable. This is because injection molding can manufacture with a short molding cycle time and high efficiency. The resin composition molded by injection molding can be referred to as an injection molded body. Further, the molded body formed by injection molding may be further processed by blow molding or the like.

[0084] <<Electronic device>> As shown in FIG. 3, the electronic device 100 of the present embodiment has resin members 10a and 10b for the electronic device of the present embodiment. Examples of the electronic device 100 include office equipment such as printers and copiers, medical equipment such as CTs, and video equipment such as projectors and displays. These various electronic devices have at least one of electrical components 13, optical components 12, and metal components 11 in addition to the resin members 10a and 10b for the electronic device of the present embodiment. These electrical components 13, optical components 12, or metal components 11 realize the functions of the electronic device 100. The metal component 11 can also be used for a housing for ensuring the mechanical strength of the electronic device 100. The volume of the resin members 10a and 10b can be 10 3 mm 3 or more. The volume of the resin members 10a and 10b is preferably 10 4 mm 3 or more, and may be 10 8 mm 3 or less, and may be 10 6 mm 3 or less. The larger the volume, the more preferably the thickness of the resin member is 0.5 mm or more, may be 1 mm or more, and may be 5 mm or less.

[0085] The resin members 10a and 10b for electronic devices can be used as members for ensuring the mechanical strength of the electronic device 100 or mechanically protecting the electronic device 100. The resin member 10a for electronic devices may be an exterior body of the electronic device 100, for example, an exterior cover. This exterior body may be fixed to a metal housing (metal part 11). The resin member 10b for electronic devices in the present embodiment may be an interior body of the device 100, for example, a mechanism part. This interior body may be fixed to a metal housing (metal part 11). It is preferable that the resin members 10a and 10b for electronic devices have radio wave shielding properties from the viewpoints of the stable operation of the electronic device 100 and suppression of radio wave radiation from the electronic device 100.

Example

[0086] The present invention will be further described below with reference to examples. The materials used in this example (including the comparative example) are as follows.

[0087] (A) Matrix resin

Table 1

[0088] (B) Ferroelectric particles

Table 2

[0089] (C) Other components

Table 3

[0090] ≪Example 1≫ (1) Production of aggregate particles 50 parts by mass of ferroelectric particles B-1, 5 parts by mass of polyvinyl butyral (Sekisui Chemical Co., Ltd. "Esrec B·KBM-2"), 2 parts by mass of dioctyl phthalate (Kanto Chemical Co., Inc. "Dioctyl Phthalate Tokubetsu Kyu"), 69 parts by mass of toluene and 46 parts by mass of ethanol were added and mixed and dispersed with a ball mill to prepare a ferroelectric slurry.

[0091] Using an applicator, this ferroelectric slurry was uniformly coated on a polyethylene terephthalate film. Then, it was dried at 80 °C for 10 minutes to obtain a ferroelectric layer. The ferroelectric layer was peeled off using a squeegee. The peeled ferroelectric layer was pulverized using a ball mill to obtain aggregated particles of the ferroelectric.

[0092] (2) Production of pellets 95 parts by mass of matrix resin A-1 and 5 parts by mass of the obtained aggregated particles were kneaded using a twin-screw extruder to obtain pellets. The melt viscosity of these pellets was measured and evaluated by the following method. The results are shown in Table 4.

[0093] <Melt viscosity> Melt viscosity: In accordance with JIS-K-7199:1999, specifically, using an Inesco fully automatic capillary rheometer (Inesco Co., Ltd.), with a capillary of d = 1 mm and L / D = 30, the melt viscosity at a shear rate of 1,000 / sec was measured. Evaluation was carried out according to the following criteria, with evaluations from A to D being high evaluations and evaluation E being a low evaluation. A: 150 Pa·s or less. B: Exceeding 150 Pa·s and 250 Pa·s or less. C: Exceeding 250 Pa·s and 400 Pa·s or less. D: Exceeding 400 Pa·s and 1,000 Pa·s or less. E: Exceeding 1,000 Pa·s.

[0094] (3) Production of molded bodies (resin members and test pieces for electronic devices) (3-1) Production of resin members for electronic devices The obtained pellets were injected into a mold simulating a resin member for electronic devices with a size of 120 mm in length, 120 mm in width, and 5 mm in thickness and a surface roughness Ra of 1.0 μm to injection-mold the resin member for electronic devices. An electron microscope observation of the ferroelectric contained in this resin member for electronic devices was performed to determine the particle diameter, aspect ratio, and number of aggregate particles. The results are shown in Table 4.

[0095] Also, for this resin member for electronic devices, the surface charge amount, dust adhesion amount, and surface roughness were measured and evaluated by the following methods. The results are shown in Table 4.

[0096] <Surface charge amount> The molded resin member for electronic devices was rubbed 100 times with a low-dust wiper (Asahi Kasei Corporation's "Bencot·S-2") and left for 10 minutes. Then, the upper part of the resin member for electronic devices was measured using a digital electrostatic potential measuring instrument (Kasuga Electric Co., Ltd.'s "KSD-0103"). It was measured 3 times, and the average was taken as the measured value.

[0097] <Dust adhesion amount> After attaching cellulose powder (Fuji Film Wako Pure Chemical Industries, Ltd.'s "Cellulose Powder Passing 38 μm") to the surface of the molded resin member for electronic devices, air was blown vigorously to remove the cellulose powder on the surface. It was evaluated according to the following criteria, with evaluations from A to D being high evaluations and evaluation E being a low evaluation. A: The cellulose powder is not attached in a non-removed state. B: After removal, the cellulose powder is not attached. C: After removal, a small amount of cellulose powder is attached. D: After removal, a large amount of cellulose powder is attached. E: After removal, the cellulose powder is attached to the entire surface.

[0098] <Surface roughness (evaluation of moldability)> The surface roughness of the molded resin member for electronic devices was measured, and the moldability was evaluated. Specifically, for the molded resin member for electronic devices, the arithmetic mean roughness (Ra) measured using a surface roughness measuring instrument in accordance with JIS-B0601 was determined, and the moldability was evaluated according to the following criteria. Ratings from A to D were considered high evaluations, and rating E was considered a low evaluation. A: 0.3 μm or less. B: Exceeding 0.3 μm and 0.5 μm or less. C: Exceeding 0.5 μm and 0.7 μm or less. D: Exceeding 0.7 μm and 1.0 μm or less. E: Exceeding 1.0 μm.

[0099] (3-2) Production of test pieces The obtained pellets were injected into a mold for cylindrical test pieces with a height of 30 mm and a diameter of 8 mm, and the test pieces were injection molded. For this test piece, the dielectric tangent was measured and evaluated by the following method. The results are shown in Table 4.

[0100] <Dielectric tangent (evaluation of electromagnetic shielding property)> The dielectric tangent of the test piece was measured, and the electromagnetic shielding property was evaluated. Specifically, for the test piece, using a perturbation method cavity resonator type DPS18 manufactured by Keycom Co., Ltd., the dielectric constant and dielectric tangent at 3 GHz were measured, and the electromagnetic shielding property was evaluated according to the following criteria. A: 0.01 or more. B: Less than 0.01 and 0.001 or more. C: Less than 0.001 and 0.0005 or more. D: Less than 0.0005 and 0.0002 or more. E: Less than 0.0002.

[0101] ≪Comparative Example 1≫ Pellets and molded bodies were produced and evaluated in the same manner as in Example 1, except that agglomerated particles were not produced and the ferroelectric powder B-5 was used as it was. The results are shown in Table 4. The surface charge amount was -4.1 kV, the dust adhesion amount was rated E, and a deterioration in the dust adhesion property was confirmed. It is considered that the large particle size of the ferroelectric particles resulted in a large surface charge amount and a deterioration in the dust adhesion property.

[0102] <<Comparative Example 2>> Pellets and compacts were produced and evaluated in the same manner as in Example 1, except that agglomerated particles were not produced and the ferroelectric powder B-2 was used as it was. The results are shown in Table 4. The melt viscosity was 2,356 Pa·s, with an E evaluation, and a deterioration in fluidity was confirmed. It is considered that the viscosity increased because the ferroelectric particles with a small particle size were dispersed in the matrix resin without agglomerating.

[0103] <<Comparative Example 3>> Agglomerated particles, pellets, and compacts were produced and evaluated in the same manner as in Example 1, except that ferroelectric particles B-3 were used. The results are shown in Table 4. The surface roughness was Ra1.61 μm, with an E evaluation, and a deterioration in surface properties was confirmed. It is considered that the surface properties deteriorated because the particle size of the agglomerated particles was large.

[0104] <<Example 2>> Agglomerated particles, pellets, and compacts were produced and evaluated in the same manner as in Example 1, except that ferroelectric particles B-2 were used. The results are shown in Table 4.

[0105] <<Example 3>> In the production of agglomerated particles, the time for grinding using a ball mill was changed to adjust the particle size and aspect ratio of the agglomerated particles. Agglomerated particles, pellets, and compacts were produced and evaluated in the same manner as in Example 2. The results are shown in Table 4.

[0106] <<Examples 4 to 7>> In the production of agglomerated particles, the time for grinding using a ball mill was changed to adjust the particle size and aspect ratio of the agglomerated particles. Agglomerated particles, pellets, and compacts were produced and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[0107] <<Example 8>> Agglomerated particles, pellets, and compacts were produced and evaluated in the same manner as in Example 1, except that ferroelectric particles B-4 were used. The results are shown in Table 4.

[0108] <<Examples 9 and 10>> Aggregate particles, pellets, and molded articles were produced and evaluated in the same manner as in Example 2, except that matrix resins A-2 and A-3 were used respectively. The results are shown in Table 5.

[0109] <<Examples 11 to 14>> Aggregate particles, pellets, and molded articles were produced and evaluated in the same manner as in Example 1, except that the blending amount of the ferroelectric particles was changed as shown in Table 5. The results are shown in Table 5.

[0110] <<Examples 15 to 21>> In the production of the pellets, aggregate particles, pellets, and molded articles were produced and evaluated in the same manner as in Example 1, except that the other components C-1 to C-7 were kneaded with the matrix resin and the aggregate particles in the amounts shown in Table 5 respectively. The results are shown in Table 5.

[0111] [Table 4]

[0112] [Table 5]

[0113] The present invention is not limited to the embodiments and examples described above, and many modifications are possible within the technical idea of the present invention. Also, the effects described in the embodiments and examples of the present invention are merely a list of the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments and examples.

[0114] In addition, new matters can be added to at least one embodiment. The disclosure of this specification includes not only what is explicitly described in this specification, but also all matters that can be grasped from this specification and the drawings attached to this specification.

[0115] Regarding the specific numerical ranges exemplified in this specification, the description "e to f" (where e and f are numbers) means "e or more" and / or "f or less". Also, regarding the exemplified specific numerical ranges, when the ranges "i to j" and "m to n" are listed together (where i, j, m, and n are numbers), the combination of the lower and upper limits is not limited to the combination of i and j or the combination of m and n. For example, it is also possible to consider combinations of the lower and upper limits of multiple sets. That is, when the ranges "i to j" and "m to n" are listed together, within a non - conflicting range, it is possible to conduct investigations in the range "i to n" or in the range "m to j". Also, being "e or more" means being "e" or greater than "e" (exceeding "e"), and it is possible to adopt a value greater than "e" without adopting "e". Also, being "f or less" means being "f" or less than "f" (less than "f"), and it is possible to adopt a value less than "f" without adopting "f".

[0116] In addition, the disclosure of this specification includes the complement sets of the individual concepts described in this specification. That is, for example, if there is a description in this specification to the effect that "A is B", even if the description to the effect that "A is not B" is omitted, it can be said that this specification discloses the fact that "A is not B". This is because when a description to the effect that "A is B" is made, it is premised that the case where "A is not B" has been considered.

[0117] ≪Constituents Included≫ The disclosure of this embodiment includes the following configurations. (Configuration 1) A resin member for an electronic device, including a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of ferroelectric particles, the particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less. A resin member characterized by this. (Configuration 2) A resin member for an electronic device, It contains a matrix resin and dielectric particles dispersed in the matrix resin. The dielectric particles are aggregate particles that are aggregates of normal dielectric particles having a relative permittivity of 10 or more. The particle diameter of the normal dielectric particles is 10 nm or more and 1,000 nm or less. A resin member, wherein the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less.

[0118] (Configuration 3) The resin member according to Configuration 1 or 2, wherein the shape of the aggregate particles is scaly. (Configuration 4) The resin member according to any one of Configurations 1 to 3, wherein the aspect ratio of the aggregate particles is 3 or more and 20 or less. (Configuration 5) The number of the aggregate particles per unit area is 1 piece / mm 2 or more and 100 pieces / mm 2 or less. The resin member according to any one of Configurations 1 to 4. (Configuration 6) The resin member according to any one of Configurations 1 to 5, wherein the particle diameter of the aggregate particles is 5 μm or more. (Configuration 7) The resin member according to any one of Configurations 1 to 6, wherein the dielectric particles contain a titanate compound. (Configuration 8) The resin member according to any one of Configurations 1 to 7, wherein the dielectric particles contain barium titanate. (Configuration 9) The resin member according to any one of Configurations 1 to 8, wherein the content of the dielectric particles is 0.1% by mass or more and 10% by mass. (Configuration 10) The resin member according to any one of Configurations 1 to 9, wherein the matrix resin is a thermoplastic resin.

[0119] (Configuration 11) The matrix resin is the resin member according to any one of Configurations 1 to 10, characterized by containing a polar polymer. (Configuration 12) The matrix resin is the resin member according to any one of Configurations 1 to 11, characterized by containing a crystalline polymer. (Configuration 13) The matrix resin is the resin member according to any one of Configurations 1 to 12, characterized by containing a polyester. (Configuration 14) The matrix resin is the resin member according to any one of Configurations 1 to 13, characterized by containing polyethylene terephthalate. (Configuration 15) The matrix resin is the resin member according to any one of Configurations 1 to 14, characterized by containing a polyester and a carbodiimide. (Configuration 16) Furthermore, the resin member according to any one of Configurations 1 to 15, characterized by containing an elastomer. (Configuration 17) Furthermore, the resin member according to any one of Configurations 1 to 16, characterized by containing filler particles mainly composed of an inorganic material other than the dielectric particles. (Configuration 18) The resin member according to Configuration 17, characterized in that the relative permittivity of the inorganic material is less than 10. (Configuration 19) Furthermore, the resin member according to any one of Configurations 1 to 18, characterized by containing at least one of a metal material containing a transition metal element, a compound material containing a transition metal element, a metal material containing a typical metal element, and a compound material containing a typical metal element, other than the dielectric particles. (Configuration 20) The volume of the resin member is 1,000 mm 3 or more, and is the resin member according to any one of Configurations 1 to 19.

[0120] (Configuration 21) A resin composition, A resin composition comprising a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of ferroelectric particles, the particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less, the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less, and the matrix resin contains polyester and carbodiimide. (Configuration 22) A resin composition comprising a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of paraelectric particles having a relative permittivity of 10 or more, the particle diameter of the paraelectric particles is 10 nm or more and 1,000 nm or less, the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less, and the matrix resin contains polyester and carbodiimide. (Configuration 23) A method for manufacturing a resin member, comprising melting the resin composition according to Configuration 21 or 22 and injecting the melted resin composition into a mold.

[0121] (Configuration 24) An electronic device comprising the resin member according to any one of Configurations 1 to 20 and at least one of an electrical component, a metal component, and an optical component. (Configuration 25) The electronic device according to Configuration 24, wherein the resin member is an exterior body.

Explanation of Reference Numerals

[0122] 1: Matrix resin, 2: Primary particles of dielectric, 3: Aggregate particles

Claims

1. A resin member for an electronic device, comprising a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of ferroelectric particles, the particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less.

2. A resin member for an electronic device, comprising a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles that are aggregates of paraelectric particles having a relative permittivity of 10 or more, the particle diameter of the paraelectric particles is 10 nm or more and 1,000 nm or less, and the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less.

3. The resin member according to claim 1 or 2, wherein the shape of the aggregate particles is scaly.

4. The resin member according to claim 1 or 2, wherein the aspect ratio of the aggregate particles is 3 or more and 20 or less.

5. The number of the aggregate particles per unit area is 1 piece / mm 2 or more and 100 pieces / mm 2 or less. The resin member according to claim 1 or 2, characterized by this.

6. The resin member according to claim 1 or 2, wherein the particle diameter of the aggregate particles is 5 μm or more.

7. The resin member according to claim 1 or 2, wherein the dielectric particles contain a titanium compound.

8. The resin member according to claim 1 or 2, wherein the dielectric particles contain barium titanate.

9. The resin member according to claim 1 or 2, wherein the content of the dielectric particles is 0.1% by mass or more and 10% by mass.

10. The resin member according to claim 1 or 2, wherein the matrix resin is a thermoplastic resin.

11. The resin member according to claim 1 or 2, wherein the matrix resin contains a polar polymer.

12. The resin member according to claim 1 or 2, wherein the matrix resin contains a crystalline polymer.

13. The resin member according to claim 1 or 2, wherein the matrix resin contains a polyester.

14. The resin member according to claim 1 or 2, wherein the matrix resin contains polyethylene terephthalate.

15. The resin member according to claim 1 or 2, wherein the matrix resin contains a polyester and a carbodiimide.

16. The resin member according to claim 1 or 2, further comprising an elastomer.

17. The resin member according to claim 1 or 2, further comprising filler particles mainly composed of an inorganic material other than the dielectric particles.

18. The resin member according to claim 17, wherein the relative dielectric constant of the inorganic material is less than 10.

19. The resin member according to claim 1 or 2, further containing at least one of a metal material containing a transition metal element, a compound material containing a transition metal element, a metal material containing a typical metal element, and a compound material containing a typical metal element, other than the dielectric particles.

20. The volume of the resin member is 1,000 mm ３ The resin member according to claim 1 or 2, characterized in that the volume is 1,000 mm or more.

21. A resin composition, comprising a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles which are aggregates of ferroelectric particles, the particle diameter of the ferroelectric particles is 10 nm or more and 1,000 nm or less, the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less, and the matrix resin contains a polyester and a carbodiimide, characterized resin composition.

22. A resin composition, comprising a matrix resin and dielectric particles dispersed in the matrix resin, wherein the dielectric particles are aggregate particles which are aggregates of paraelectric particles having a relative dielectric constant of 10 or more, the particle diameter of the paraelectric particles is 10 nm or more and 1,000 nm or less, the particle diameter of the aggregate particles is 1 μm or more and 100 μm or less, and the matrix resin contains a polyester and a carbodiimide, characterized resin composition.

23. A method for manufacturing a resin member, characterized by melting the resin composition according to claim 21 or 22 and injecting it into a mold.

24. An electronic device, characterized by having the resin member according to claim 1 or 2 and at least one of an electrical component, a metal component, and an optical component.

25. The electronic device according to claim 24, wherein the resin member is an exterior body.

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