JP5187042B2 - Resin composition for dielectric and dielectric antenna - Google Patents

Description

  The present invention relates to a dielectric antenna component suitable for use in a high frequency region and a dielectric resin composition suitable as a material for the dielectric antenna component.

  2. Description of the Related Art Conventionally, surface-mounted dielectric antennas used for mobile communication devices such as cellular phones and wireless LANs have been proposed that are composed of a dielectric ceramic simple substance, a resin simple substance, and a ceramic-containing resin composition. For example, a surface mount dielectric antenna whose antenna base is made of a ceramic or a resin (Patent Document 1), a styrene resin having a syndiotactic structure with good plating properties and a real part of a relative dielectric constant of about 1.8 And a method of manufacturing the same (Patent Document 2). Furthermore, a resin composition in which spherical dielectric ceramic powder is mixed with a resin material in a proportion of 40 vol% to 70 vol% (volume%) in the composition (Patent Document 3), an aspect ratio of 3 is required to enable high filling. The composite material (patent document 4) which compounded the metal titanate salt fiber adjusted to -5, this, and a thermoplastic resin etc. is disclosed. However, when a metal titanate salt fiber and a thermoplastic resin are melt-kneaded for compounding, the fiber breaks and the aspect ratio becomes small. However, Patent Document 4 discloses a metal titanate salt in a composite material after melt-kneading. The fiber aspect ratio is not described.

JP-A-9-98015 JP 10-45936 A Japanese Patent No. 3930814 Japanese Patent No. 2992667

  By the way, in recent years, with the reduction in weight and size of mobile communication devices such as mobile phones, there is an increasing demand for weight reduction and size reduction of dielectric antennas. However, conventional antennas made of dielectric ceramics and antennas made of resin alone have the following problems.

  That is, in an antenna made of a dielectric ceramic alone, not only does the antenna substrate forming process and firing process take time, but the processability and formability are inferior, making it difficult to create an antenna having a complicated shape. . In addition, the antenna can be downsized by using ceramics with a high dielectric constant, but the antenna has a size effect. There is. Therefore, it is necessary to use a material with a small specific gravity in order to reduce the weight of the antenna. However, dielectric ceramics have a large specific gravity and have a problem that they cannot cope with the weight reduction of the antenna.

Further, in the antenna base made of a single resin, the resin has a small specific gravity and is excellent in moldability and workability, but there is a problem that it cannot cope with the miniaturization of the antenna because the relative dielectric constant is small. In the case of a composite material in which a ceramic powder having a relatively small aspect ratio with a spherical shape or an aspect ratio of 3 to 5 is combined with a resin, a high dielectric constant cannot be obtained unless the addition amount of the ceramic powder is increased. As a result, there is a problem that the specific gravity is high and the antenna cannot be reduced in weight. In addition, in the case of a resin having a low electrical resistivity or a high dielectric loss tangent, the function of the dielectric antenna cannot be achieved. Therefore, the antenna material has a volume resistivity of 1 × 10 ¹² Ωcm or more and a dielectric loss tangent of 0.3. The following are required: Furthermore, strength is required as a resin for a dielectric antenna for a mobile phone.

  Accordingly, an object of the present invention is to provide a dielectric resin composition having a high real part of relative dielectric constant and a volume resistivity and a low dielectric loss tangent, excellent mechanical strength, workability and moldability, and having a low specific gravity, And it is providing the dielectric antenna component using the same.

According to the present invention, at least (a1) a polyphenylene ether containing resin and (a2) shea Nji syndiotactic styrene resins, (a1) a polyphenylene ether resin and (a2) syndiotactic polystyrene down trees syndiotactic in the total fat and a resin material proportion of tick polystyrene down resins is less than 75 wt% to 25 wt%, a resin composition obtained by melt-kneading (B) rutile type fibrous titanium oxide, are contained (B ) The average diameter of rutile fibrous titanium oxide is 0.3 to 0.7 μm, the average aspect ratio is 4 or more, and the proportion of (B) rutile fibrous titanium oxide in the resin composition is 10 volumes. The above object can be achieved by a dielectric resin composition characterized by being no less than 30% and no more than 30% by volume.

  Since the resin composition according to the present invention has a relatively small specific gravity and excellent properties as a dielectric, it also has excellent mechanical strength and workability, so that it can be used for antenna parts such as mobile phones. Suitable for material.

  The dielectric resin composition of the present invention is obtained by melt-kneading a resin material and a rutile fibrous titanium oxide having a high aspect ratio. In the present invention, the “resin composition” is a resin composition obtained through a step of melt-kneading at least the component (A) and the component (B). For example, pellets obtained by melt-kneading , Molded products obtained by molding the pellets, and molded products obtained by other methods.

(A) Resin material As the resin material to be the base material of the resin composition, a material having a low dielectric loss tangent is preferable. The resin may be either a thermoplastic resin or a thermosetting resin, but a thermoplastic resin capable of injection molding is preferred. For example, polyolefin resins such as low density polyethylene, ultra low density polyethylene, ultra ultra low density polyethylene, high density polyethylene, low molecular weight polyethylene, ultra high molecular weight polyethylene, ethylene-propylene copolymer, polypropylene, polyphenylene ether resin and polystyrene Alloy with resin, alloy with polyphenylene ether resin and polyamide resin, alloy with polyphenylene ether resin and polyolefin resin, polycarbonate resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polyamide 6, polyamide 66, polyamide MXD6, polyacetal Examples thereof include engineering plastics such as resins and alloys containing these. If desired, high heat-resistant super engineering plastics such as liquid crystal polymer, polyphenylene sulfide resin and polyimide resin and alloys containing these can also be used.

Particularly preferred as the resin material of the present invention is an alloy of a polyphenylene ether resin and a polystyrene resin in that it is excellent in molding processability and mechanical properties and has a low dielectric loss tangent.
The polyphenylene ether resin is a polymer having a structural unit represented by the following general formula (1) in the main chain, and may be either a homopolymer or a copolymer.

(The two R ^{1 s} may be the same or different and are each a hydrogen atom, a halogen atom, a primary or secondary alkyl group, an aryl group, an aminoalkyl group, a haloalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group. The two R ^{2 s} may be the same or different and are each a hydrogen atom, a halogen atom, a primary or secondary alkyl group, an aryl group, a haloalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group; However, the two R ^{1 s} are not both hydrogen atoms.)

R ¹ and R ² are preferably a hydrogen atom, a primary or secondary alkyl group, or an aryl group. Preferable examples of the primary alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, n-amyl group, isoamyl group, 2-methylbutyl group, 2,3-dimethylbutyl group, 2 -, 3- or 4-methylpentyl group or heptyl group may be mentioned. Preferable examples of the secondary alkyl group include isopropyl group, sec-butyl group or 1-ethylpropyl group, and aryl group includes phenyl group. Particularly preferred as R ¹ is a primary or secondary alkyl group having 1 to 4 carbon atoms or a phenyl group. R ² is preferably a hydrogen atom.

  Suitable polyphenylene ether resins include poly (2,6-dimethyl-1,4-phenylene ether), poly (2,6-diethyl-1,4-phenylene ether), poly (2,6-dipropyl-1, 2,6-dialkylphenylene ethers such as 4-phenylene ether), poly (2-ethyl-6-methyl-1,4-phenylene ether), poly (2-methyl-6-propyl-1,4-phenylene ether) These homopolymers are mentioned.

  2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer, 2,6-dimethylphenol / 2,3,6-triethylphenol copolymer, 2,6-diethylphenol / 2,3 2,6-dialkylphenol / 2,3,6-trialkylphenol copolymers such as 2,6-tripropylphenol copolymer and 2,6-dipropylphenol / 2,3,6-trimethylphenol copolymer are also preferred. . Furthermore, a graft copolymer obtained by graft-polymerizing styrene to poly (2,6-dimethyl-1,4-phenylene ether), a styrene to a 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer. Also preferred are graft copolymers obtained by graft polymerization.

  Among these polyphenylene ether resins, poly (2,6-dimethyl-1,4-phenylene ether) and 2,6-dimethylphenol / 2,3,6-trimethylphenol random copolymer are particularly preferable. In addition, polyphenylene ether resins that define the number of terminal groups and the copper content as described in JP-A-2005-344065 can also be suitably used.

  The molecular weight of the polyphenylene ether resin is preferably 0.2 to 0.8 dl / g, more preferably 0.3 to 0.6 dl / g in intrinsic viscosity measured at 30 ° C. in chloroform. When the intrinsic viscosity is less than 0.2 dl / g, the mechanical strength of the resulting resin composition tends to decrease. On the other hand, when a material having a value larger than 0.8 dl / g is used, the fluidity of the resin composition is deteriorated and the molding process tends to be difficult. Two or more kinds of polyphenylene ether resins may be used in combination, and in this case, those having different intrinsic viscosities may be mixed to obtain a desired intrinsic viscosity.

  As is well known, polyphenylene ether resins are industrially produced on a large scale by oxidative coupling reactions of phenol compounds. Various catalysts for the oxidative coupling reaction are known. For example, an amino compound and at least one heavy metal compound such as copper, manganese and cobalt are usually used in combination with various other substances. Yes. Examples of the catalyst for the oxidative coupling reaction include US Pat. Nos. 4,042,056, 3,306,874, 3,306,875, 3,365,422, and 3,639,656. No. 3,642,699, 3,733,299, 3,838,102, 3,661,848, 5,037,943 and the like. In the present invention, a polyphenylene ether resin produced using any catalyst can be used.

Examples of polystyrene resins used in combination with polyphenylene ether resins include styrene monomer polymers, copolymers of styrene monomers with other copolymerizable monomers, and styrene graft copolymers. Can be mentioned.
Examples of the styrenic monomer include styrene, α-methyl styrene, p-methyl styrene, etc., and styrene is preferably used. Examples of the monomer copolymerizable with the styrenic monomer include vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, methyl acrylate, ethyl acrylate, propyl acrylate, methyl methacrylate, and methacrylic acid. Examples include (meth) acrylic acid alkyl ester monomers such as ethyl, and maleimide monomers such as maleimide and N-phenylmaleimide. Among these, it is preferable to use a vinyl cyanide monomer and a (meth) acrylic acid alkyl ester monomer.

  As a polymer of polystyrene monomers, syndiotactic polystyrene has a lower dielectric loss tangent than ordinary polystyrene (GPPS), an excellent balance between dielectric constant and volume resistivity, and also excellent heat resistance. It is preferable to use GPPS in terms of price. AS copolymer etc. are mentioned as a copolymer of a styrene-type monomer and another copolymerizable monomer. Examples of the styrene-based graft copolymer include HIPS resin, ABS resin, AES resin, and AAS resin. The proportion of the styrene monomer in these copolymers is preferably 40 to 99% by weight. The molecular weight of the polystyrene resin is preferably 50,000 to 400,000 as a weight average molecular weight. The proportion of the polystyrene resin in the total of the polyphenylene ether resin and the polystyrene resin is usually 25% by weight or more and 75% by weight or less.

(B) Rutile-type fibrous titanium oxide Since rutile-type titanium oxide has a large relative dielectric constant real part compared to anatase-type titanium oxide, when it is contained in a resin material, a resin composition having a large relative dielectric constant real part is provided. In addition, rutile titanium oxide can be made into a fibrous shape, that is, a shape with a high aspect ratio, so that when it is contained in a resin, the relative permittivity real part in the fiber major axis direction can be effectively improved. Is possible.

  As a rutile type fibrous titanium oxide, a higher aspect ratio can develop a higher dielectric constant with a smaller content. This is presumably because, during molding such as injection molding, fibrous titanium oxide having a higher aspect ratio tends to be oriented in the flow direction in the fiber length direction, and the fibers are more easily aligned in one direction. In the present invention, the average aspect ratio in the resin composition (pellets, molded articles, etc.) needs to be 4 or more, preferably 4.5 or more, and more preferably 5 or more. As will be apparent from the examples described later, the larger the aspect ratio, the better the performance as a dielectric and the mechanical strength. Therefore, the average aspect ratio is preferably 5.5 or more, particularly 6 or more. However, the size of the aspect ratio and the dielectric constant are not necessarily proportional, and the rutile-type fibrous titanium oxide having a larger aspect ratio is significantly broken by melt-kneading, becomes difficult to melt-knead, and has a higher dielectric loss tangent value. There is a tendency. Therefore, it is preferable to use a rutile-type fibrous titanium oxide that is used for compounding, that is, used as a raw material before melt-kneading, having an average aspect ratio of 200 or less, particularly 100 or less. Even when such a large aspect ratio is used, it is broken by melt-kneading, so it is difficult to make the average aspect ratio in the resin composition larger than 50, and it is usually 20 or less.

  The average diameter of the rutile fibrous titanium oxide is 0.2 to 2 μm. If the average diameter is too small, the bulk specific gravity becomes small, so that it becomes difficult to obtain a uniform resin composition by melt kneading. Further, in a conventional single-screw or twin-screw kneader, there is a problem that when kneading is attempted, the screw is idle and kneading cannot be performed, or the discharge rate is lowered and productivity is lowered. Further, since the specific surface area increases, the resin material may be deteriorated.

  Conversely, if the average diameter is too large, the fiber length must be increased to ensure the aspect ratio. However, if the fiber length is long, melt-kneading becomes difficult, and the fiber is easily broken during melt-kneading or injection molding, and there is a problem that the aspect ratio of the rutile-type fibrous titanium oxide in the resin composition or molded product cannot be maintained high. Furthermore, since it takes time to grow rutile fibrous titanium oxide, there is also a problem that a product having a large diameter and a large aspect ratio is expensive to manufacture. The average diameter of the rutile fibrous titanium oxide is preferably 0.3 to 0.7 μm.

  In the present specification, the average diameter and average aspect ratio of the rutile-type fibrous titanium oxide used can be determined by the following method. Observation with a scanning electron microscope at a magnification of 1,500 to 5,000 times, and after measuring the diameter and fiber length of 500 rutile-type fibrous titanium oxides, the arithmetic average of the diameter and the arithmetic average of the fiber length And the average aspect ratio was determined as the ratio.

In addition, for the purpose of improving the dispersibility during the production of rutile-type fibrous titanium oxide and the dispersibility in the resin composition, the surface of the rutile-type fibrous titanium oxide is treated with an inorganic or organic treatment agent in advance. Also good.
As the inorganic treatment agent, alumina, zirconia, silica, a mixture thereof, or the like is used. Silica has high water absorption, and when it is used as a resin composition, it is susceptible to moisture such as decomposition of resin components and defective appearance of molded products. Therefore, when inorganic treatment is performed, alumina and zirconia are preferable, and silica is used in combination. In this case, it is preferable that the amount of silica is small. Although the usage-amount of these inorganic processing agents should just be selected and determined suitably, it is 2 to 5 weight% normally with respect to a rutile type fibrous titanium oxide. If the content of the inorganic treatment agent is too much with respect to titanium oxide, the strength reduction and appearance defects of the resin molded product formed by molding the resin composition with the adsorbed water contained in the inorganic treatment layer on the surface of titanium oxide are problematic. There is a case. Conversely, if the amount is too small, the improvement effect may be insufficient, such as insufficient dispersibility.
Examples of the organic treating agent include an organosilane compound or an organosilicone compound having an alkoxy group, an epoxy group, an amino group, or a Si—H bond. Preferred is an organosilicone compound having a Si—H bond from the viewpoint of dispersibility in the resin composition, adhesion to the resin component, and the like. Of these, hydrogenpolysiloxane is particularly preferred. The amount of these organic treatment agents used is usually 0.5 to 5% by weight, preferably 1 to 3% by weight, based on titanium oxide.

  The content of (B) rutile-type fibrous titanium oxide in the resin composition (pellets, molded articles, etc.) is preferably 5% by volume to 40% by volume, particularly preferably 10% by volume to 30% by volume. If it is 5% by volume or less, the effect of improving the relative dielectric constant is small, and if it is 40% by volume or more, there is a problem that the mechanical strength of the resin composition is lowered and the productivity is also lowered.

  The resin composition of the present invention is preferably blended with a thermal stabilizer in order to improve the thermal stability in a high-temperature atmosphere during melt kneading in the production and molding process of the resin composition and when the product is used. As the heat stabilizer, hindered phenol compounds, phosphite compounds, phosphonite compounds, zinc oxide, and the like are preferable.

  As a hindered phenol type compound, what has the partial structure shown by following General formula (2) is preferable.

(However, in the formula, each R ³ independently represents a hydrocarbon group having 1 to 10 carbon atoms.)

  Specific examples of hindered phenol compounds include 2,6-di-t-butyl-4-methylphenol and -octadecyl-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl). Propionate, 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3- (3 ′, 5′-di-t -Butyl-4′-hydroxyphenyl) propionate], 3,9-bis [1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxypheny ) Propionate],

3,5-di-tert-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxy Benzyl) benzene, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], tris- (3,5-di-t-butyl-4-hydroxy Benzyl) -isocyanurate, N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamide), and the like.

  Among these, 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate, 1,6- Hexanediol-bis [3- (3 ′, 5′-t-butyl-4′-hydroxyphenyl) propionate], 3,9-bis [1,1-dimethyl-2- {β- (3-t-butyl) -4-Hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane is preferred.

  As the phosphite compound or phosphonite compound, those represented by the following general formula (3) or the following general formula (4) are preferable.

(However, in the formula, each R ⁴ independently represents a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or an aryl group having 6 to 30 carbon atoms, and at least one R ⁴ is a carbon atom. Represents an aryl group having 6 to 30 atoms.)

(In the formula, each R ⁵ independently represents a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or an aryl group having 6 to 30 carbon atoms, and at least one R ⁵ represents a carbon atom. Represents an aryl group of formula 6-30.)

  Examples of the phosphite compound represented by the general formula (3) include tris (2,4-di-t-butylphenyl) phosphite and bis (2,4-di-t-butylphenyl) pentaerythritol-di-. Phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octyl phosphite, 4 , 4'-Butylidene-bis (3-methyl-6-tert-butylphenyl-di-tridecyl) phosphite, 1,1,3-tris (2-methyl-4-ditridecyl phosphite-5-tert-butyl -Phenyl) butane, tris (mixed mono and di-nonylphenyl) phosphite, tris (nonylphenyl) phosphite, 4,4'-isopropylide Bis (phenyl - dialkyl phosphite), and the like. Among these, tris (2,4-di-t-butylphenyl) phosphite is preferable.

  Examples of the phosphonite compound represented by the general formula (4) include tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylenephosphonite, tetrakis (2,4-di-t-butyl). Phenyl) [1,1-biphenyl] -4,4′-diylbisphosphonite and the like.

  Zinc oxide preferably has an average particle size of 0.02 to 1 μm, more preferably 0.08 to 0.8 μm, from the viewpoint of dispersibility and thermal stability. As zinc oxide, products of Honjo Chemical Co., Ltd., Sakai Chemical Industry Co., Ltd., and Shodo Chemical Industry Co., Ltd. can be used. The average particle diameter is usually a notarized value (value described in Kaalog etc.) of the manufacturer.

  The compounding quantity of these heat stabilizers is 0.01-5 weight part in total with respect to 100 weight part of (A) resin materials normally. When the blending amount of the heat stabilizer is less than 0.01 parts by weight, the effect of improving the heat stability is small. Moreover, even if it mix | blends in the quantity exceeding 5 weight part, not only the improvement effect of thermal stability will not become large, but in the case of a phosphite type compound and a phosphonite type compound, since a mold deposit occurs, it is not preferable.

  It is also preferable to add a flame retardant to the resin composition of the present invention. As the flame retardant, a phosphate flame retardant is preferable. Some examples are phenyl resorcin polyphosphate, cresyl resorcin polyphosphate, phenyl cresyl resorcin polyphosphate, xylyl resorcin polyphosphate, phenyl-pt-butylphenyl resorcin polyphosphate And condensed phosphate ester compounds such as phenyl, isopropylphenyl, resorcinol, polyphosphate, cresyl, xyler, resorcinol, polyphosphate, phenyl, isopropylphenyl, diisopropylphenyl, resorcinol, polyphosphate, bisphenol A-bis (diphenyl phosphate) It is done.

  Phosphorus such as triphenyl phosphate, tricresyl phosphate, diphenyl-2-ethyl cresyl phosphate, tri (isopropylphenyl) phosphate, methyl phosphonic acid diphenyl ester, phenylphosphonic acid diethyl ester, diphenyl cresyl phosphate, tributyl phosphate, etc. Acid esters are also mentioned. Two or more of these compounds may be used in combination.

  The compounding quantity of a phosphate flame retardant is 1-30 weight part with respect to 100 weight part of (A) resin materials, Preferably it is 5-25 weight part. If the blending amount of the phosphate flame retardant is less than 1 part by weight, the flame retardant effect is small, and if it exceeds 30 parts by weight, the load deflection temperature may be lowered or mold contamination may occur.

Other components can be added to the resin composition of the present invention as necessary. Examples of such additives include fillers, reinforcing materials, weather resistance improvers, foaming agents, lubricants, fluidity improvers, impact resistance improvers, dyes, pigments, and dispersants.
For example, as a filler or a reinforcing agent, both organic and inorganic can be used. Usually, glass fiber, mica (white mica, black mica, gold mica, etc.), alumina, talc, wollastonite, potassium titanate, It is preferable to use inorganic substances such as calcium carbonate and silica. These are preferably blended so as to be 1 to 100 parts by weight, more preferably 5 to 80 parts by weight, and further preferably 5 to 60 parts by weight with respect to 100 parts by weight of the resin material (A). When these are blended, generally rigidity, heat resistance, dimensional accuracy, etc. can be improved. Among these, white mica and alumina are more preferable because they have an effect of reducing the dielectric loss tangent. The amount of white mica or alumina is preferably 5 to 100 parts by weight, more preferably 10 to 50 parts by weight, based on 100 parts by weight of the resin material (A).

The resin composition of the present invention is produced through a step of melt-kneading at least (A) a resin material and (B) rutile-type fibrous titanium oxide. For example, pellets obtained by melt-kneading, the pellets A molded product obtained by molding a molded product, and a molded product obtained by other methods.
The pellets obtained by melt-kneading include, for example, (A) resin material, (B) rutile-type fibrous titanium oxide, and further, if necessary, additives as described above, Henschel mixer, ribbon blender, V-type After uniformly mixing with a blender or the like, it can be produced by kneading with a single-screw or multi-screw kneading extruder, roll, Banbury mixer, Laboplast mill (Brabender) or the like. Instead of mixing and kneading all the components at once, some components can be mixed in advance or supplied in the middle of kneading without mixing in advance. In kneading, it is inevitable that rutile-type fibrous titanium oxide is usually broken to some extent. Therefore, rutile-type fibrous titanium oxide having an aspect ratio larger than the desired aspect ratio is used as the resin composition. Used as a raw material. When there is a high risk of breakage, for example, when a twin-screw kneading extruder is used, it is preferable to perform so-called side feed, in which the rutile fibrous titanium oxide is supplied from the middle of the extruder.

  The kneading temperature and kneading time vary depending on the intended resin composition and the type of the kneader, but usually the kneading temperature is 200 to 350 ° C., preferably 220 to 320 ° C., and the kneading time is preferably 20 minutes or less. When the temperature exceeds 350 ° C. or 20 minutes, the resin material has a problem of thermal deterioration, which may cause deterioration of physical properties and appearance defects of the molded product.

  The resin composition pellets thus obtained use molding methods generally used for thermoplastic resins, such as injection molding methods, extrusion molding methods, hollow molding methods, thermoforming methods, press molding methods, etc. Can be made into a molded product. Among them, the injection molding method is preferable from the viewpoint of productivity and product performance.

The dielectric resin composition of the present invention is suitable for dielectric antenna components. For use in a derivative antenna component, the real part of relative permittivity is preferably 5 or more, and more preferably 6 or more. The dielectric loss tangent is preferably 0.3 or less, and more preferably 0.2 or less. Further, the volume resistivity is preferably 1 × 10 ¹² Ωcm or more, and more preferably 1 × 10 ¹⁴ Ωcm or more.

The derivative antenna using the molded article of the present invention includes, for example, a parallel plate antenna in which a metal conductor is sandwiched between the dielectric resin composition molded articles of the present invention, or a microstrip line type antenna. In addition, there is a surface-mounted antenna in which an electrode bent in a U-shape is disposed on the surface of the dielectric resin composition molded product of the present invention.
As a molded article used for the above-described derivative antenna, for example, a flat plate shape (having a rib may have a long side of 3 to 5 cm, a short side of 0.1 to 1 cm, and a thickness of 2 mm or less). ), And box-shaped ones. The relative permittivity real part, which is one of the performances required for dielectric materials, is related to the degree of orientation of the fibrous titanium oxide in the resin composition, and the relative permittivity real part improves as the degree of orientation increases. . Therefore, when the thickness of the molded product is thinner, specifically, when the thickness is 1 mm or less, the fibrous titanium oxide is more easily oriented, and the effects of the present invention are more exhibited.
In order to further align the fibrous titanium oxide, it is preferable to use an injection molding method. In the case of injection molding, the molding conditions such as the injection speed are adjusted in consideration of the shape of the molded product so that the resin flow rate in the mold is preferably 50 mm / s or less, more preferably 20 mm / s. It is preferable. Moreover, it is preferable to arrange | position the gate arrange | positioned at a metal mold | die at the edge part of a molded article so that fibrous titanium oxide may orientate in one direction.

The resin composition molded article for a dielectric according to the present invention can be suitably used in the GHz band, and can have a high real part of dielectric constant and a dielectric loss tangent when the frequency band is 2.45 GHz. In addition, it can have an electrical resistivity of 1 × 10 ¹² Ωcm or more while maintaining such high dielectric properties.
Therefore, the resin composition molded article for dielectrics according to the present invention is suitable for dielectric antenna parts used for mobile communication devices such as mobile phones and notebook personal computers and wireless LANs, and particularly for surface mount type derivative antenna parts. .

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.
In the following examples, the following components were used.

(A) Resin material (a1-1) Polyphenylene ether resin:
Poly (2,6-dimethyl-1,4-phenylene) ether (hereinafter abbreviated as “PPE”);
Mitsubishi Engineering Plastics Co., Ltd., “trade name: PX100L”, intrinsic viscosity of 0.47 dl / g at 30 ° C. measured in chloroform.

(A2) Polystyrene resin:
(A2-1) polystyrene resin (hereinafter abbreviated as “GPPS”);
“Product name: HF-77” manufactured by Nippon Polystyrene Co., Ltd., weight average molecular weight 220,000.
(A2-2) Syndiotactic polystyrene resin (hereinafter abbreviated as “SPS”);
Idemitsu Kosan Co., Ltd. product, “Zarek 300ZC”, MFR 30 g / 10 min (however, measured at 300 ° C. × 1.2 kg).
(A2-3) High impact polystyrene resin (hereinafter abbreviated as “HIPS”);
“Product name: HT478”, weight average molecular weight 200,000, MFR 3.0 g / 10 min (however, measured at 200 ° C. × 5 kg).

Titanium compound (B-1) rutile-type fibrous titanium oxide;
“Product name: FTL-300” manufactured by Ishihara Sangyo Co., Ltd., average diameter 0.4 μm, average fiber length 5 μm, average aspect ratio 12.5.
(B-2) rutile-type fibrous titanium oxide;
Ishihara Sangyo Co., Ltd., “trade name: FTL-400”, average diameter 0.5 μm, average fiber length 10 μm, average aspect ratio 20.
(B-3) rutile-type fibrous titanium oxide;
“Product name: PFR-404”, average diameter 0.4 μm, average fiber length 3 μm, average aspect ratio 7.5, manufactured by Ishihara Sangyo Co., Ltd.

(B-4) Rutile fibrous titanium oxide;
“Product name: ST-485SA15” manufactured by Titanium Industry Co., Ltd., average diameter 0.01 μm, average fiber length 0.07 μm, average aspect ratio 7.
(B-5) particulate titanium oxide;
Ishihara Sangyo Co., Ltd. “trade name: PC-3”, average diameter 0.18 μm, average aspect ratio 1.
(B-6) particulate barium titanate;
“Product name: HPBT-1” manufactured by Fuji Titanium Industry Co., Ltd., average diameter 0.18 μm, average aspect ratio 1.

(C) heat stabilizer (C-1) 2,6-di-t-butyl-4-methylphenol;
"Product name: Sumilyzer BHT" manufactured by Sumitomo Chemical Co., Ltd.
(C-2) tetrakis (2,4-di-t-butylphenyl) [1,1-biphenyl] -4,4′-diylbisphosphonite;
“Product name: IRGAFAS P-EPQ” manufactured by Ciba Specialty Chemicals

(D) Release agent (D-1) low molecular weight polyethylene;
“Product name: Sunwax 151-P” manufactured by Sanyo Chemical Industries, Ltd., average molecular weight of about 2,000

[Examples 1-6, Comparative Examples 1-4]
Polyphenylene ether resin, polystyrene resin, titanium compound, heat stabilizer and release agent were blended in the ratio shown in Table 1, and mixed uniformly with a tumbler mixer. This is put into the upstream part of a twin screw extruder (Ikegai Co., Ltd., “PCM30”, screw diameter 30 mm, L / D = 42) and melt kneaded at a cylinder temperature of 270 ° C. and a screw rotation speed of 150 rpm to obtain a resin composition Pellets were produced. After the obtained resin composition was dried at 80 ° C. for 4 hours, the following evaluations (2) to (5) were performed. The evaluation results are shown in Table 1.

[Evaluation method]
(1) Average aspect ratio About 2 g of the resin composition pellets obtained by the above method were weighed and ashed in an electric furnace at 600 ° C. (“Electric Muffle Furnace KM-28” manufactured by Toyo Seisakusho Co., Ltd.) for 2 hours. After burning only the components, the remaining rutile-type fibrous titanium oxide was enlarged to 1,500 to 5,000 times using a scanning electron microscope (manufactured by Hitachi, Ltd., “S-4100”). The diameter and fiber length of 500 rutile-type fibrous titanium oxides were measured. The average aspect ratio was determined from the arithmetic average of the obtained diameters and the arithmetic average of the fiber lengths.

(2) Density Using the resin composition pellets obtained by the method described above, using an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., “SH100”, mold clamping force 100 t), a cylinder temperature of 290 ° C. to 310 ° C., gold A plate-shaped molded article having a mold temperature of 100 ° C. and having a size of 100 mm × 100 mm × thickness 2 mm was produced. About 2 g was cut out from the obtained plate-shaped molded article, and the density was measured by A method (underwater substitution method) of ISO 1183 standard.

(3) Dielectric constant Using the resin composition pellets obtained by the above method, the cylinder temperature was 290 ° C. to 310 ° C. with an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., “SH100”, clamping force 100 t), A plate-shaped molded article having a mold temperature of 100 ° C. and having a size of 100 mm × 100 mm × thickness 2 mm was produced. The plate-shaped molded product was machine-cut to a width of 0.5 mm so that the flow direction was the longitudinal direction, and processed into a rod-shaped molded product of 100 mm × 0.5 mm × thickness 2 mm. Using this rod-shaped molded product, a dielectric constant measuring device combining “Network Analyzer N5230A” manufactured by Agilent Technologies and “Cylinder Cavity Resonator CP481 for 2.45 GHz” manufactured by Kanto Electronics Application Development Co., Ltd. The real part of dielectric constant and the dielectric loss tangent were measured.

(4) Volume resistivity Using the resin composition pellets obtained by the above method, the cylinder temperature was 290 ° C to 310 ° C with an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., "SH100", mold clamping force 100t). A plate-shaped molded product having a size of 100 mm × 100 mm × thickness 2 mm was manufactured under the conditions of a mold temperature of 100 ° C. About the obtained plate-shaped molded article, the volume resistivity was measured using a digital ultrahigh resistance / micro-ammeter “ADVANTEST Co., Ltd.,“ R8340 ”).

(5) Bending strength Using the resin composition pellets obtained by the above method, the cylinder temperature 260 was measured with an injection molding machine (Sumitomo Heavy Industries, Ltd., “SG75 Cycap M-2”, clamping force 100 t). ISO test pieces were produced under the conditions of 280 ° C to 280 ° C and a mold temperature of 80 ° C. Using the obtained ISO test piece, the flexural modulus and the bending strength were measured in accordance with the ISO178 standard.

Claims (4)

Comprises at least (a1) a polyphenylene ether resin and (a2) shea Nji syndiotactic styrene resins, (a1) and polyphenylene ether resin (a2) syndiotactic polystyrene emissions resins total accounts syndiotactic polystyrene down trees fat A resin composition obtained by melt-kneading a resin material having a ratio of 25% by weight or more and 75% by weight or less and (B) rutile-type fibrous titanium oxide, containing (B) rutile-type fibrous oxidation The average diameter of titanium is 0.3 to 0.7 μm, the average aspect ratio is 4 or more, and the proportion of (B) rutile-type fibrous titanium oxide in the resin composition is 10% by volume to 30% by volume. A dielectric resin composition, comprising:   2. The dielectric resin composition according to claim 1, wherein an average aspect ratio of (B) rutile-type fibrous titanium oxide in the resin composition is 5 or more.   A dielectric antenna component obtained by injection molding the dielectric resin composition according to claim 1.   A dielectric antenna comprising the dielectric antenna component according to claim 3.