WO2009072641A1 - Liquid crystalline polyester, and molded article thereof - Google Patents

Abstract

Disclosed is a liquid crystalline polyester resin composition comprising a liquid crystalline polyester and a high dielectric material filler. Also disclosed is a molded article of the liquid crystalline polyester resin composition. The liquid crystalline polyester resin composition comprises: 50 to 80% by volume of a liquid crystalline polyester which contains a 2,6-naphthalenediyl group as an aromatic group in an amount of 40% by mole or more, which has a fluidization initiation temperature of 280˚C or higher, and which has a melt tension of 1 g or more as measured at a temperature higher than the fluidization initiation temperature; and 20 to 50% by volume of a high dielectric material filler. The liquid crystalline polyester resin composition can be made into a composition pellet readily and stably by a strand process or the like. A molded article produced from the liquid crystalline polyester resin composition has excellent flexural strength and dielectric properties.

Description

 Description Liquid crystalline polyester and molded body thereof Technical Field

 The present invention relates to a liquid crystal polyester resin composition containing liquid crystal polyester and a filler made of a high dielectric material, a method for producing the same, and a molded body using the liquid crystal polyester resin composition. Background branch

 With the development of wireless communications networks such as satellite communications equipment, mobile communications such as mobile phones and PHS, wireless LAN systems, highway ETC systems, and in-vehicle communications such as GPS, information communications equipment Demand for antennas used in the market is increasing rapidly. Since such an antenna is required to be smaller and lighter and cheaper, a thermoplastic resin is used for a base for antenna manufacture (hereinafter referred to as “antenna base”). A molded body is used.

 In manufacturing the antenna, it is necessary to form a conductor layer that can serve as an electrode on the antenna substrate. As a means for forming this electrode, means such as soldering or metal plating is adopted. Therefore, the antenna substrate is required to have such durability that the characteristics are not impaired by these electrode forming means. The In order to satisfy these characteristics, liquid crystal polyester has attracted attention as a thermoplastic resin used in the manufacture of antenna substrates. Liquid crystal polyester has both high heat resistance and heat resistance and low water absorption, so that the durability of the antenna is good as well as the durability of the antenna.

On the other hand, in the information communication equipment as described above, as information is further densified, suitability for information communication using electromagnetic waves in the high frequency range has been studied. An antenna substrate having excellent dielectric properties has been demanded. The dielectric characteristics required for such an antenna substrate include a high relative dielectric constant (high dielectric property) for electromagnetic waves in a high frequency region and a low dielectric loss tangent. It is important. This is because a high dielectric antenna substrate does not significantly deteriorate the antenna characteristics even with a relatively small antenna, and an antenna gain increases with a low dielectric loss tangent antenna substrate. This is because there is a tendency to do so. To obtain a high dielectric antenna substrate, a high dielectric material is used as a filler (hereinafter referred to as

And a method of obtaining an antenna substrate from a resin composition containing the high dielectric material filler and a liquid crystal polyester. For example, in Japanese Patent Application Laid-Open No. 2 00 4-1 6 1 9 5 3, a composition containing 25 to 35% by volume of liquid crystal polyester and 65 to 75% by volume of ceramic powder is melt-mixed, Thereafter, a tablet for antenna parts that has been converted into a tablet at room temperature by a tableting machine is disclosed, and it is disclosed that a tablet for antenna parts having excellent shape retention can be obtained by using a wax component together during melt mixing.

 In addition, the inventors of the present application have proposed a resin composition containing a liquid crystal polyester having a specific structural unit and ceramic powder as a resin composition from which a molded article having a high dielectric property and a low dielectric loss tangent can be obtained. (Refer to Japanese Patent Laid-Open No. 2000-062 3 3 1 1 8). Disclosure of the invention

 By the way, a resin composition containing a liquid crystal polyester and a filler is prepared by melting and kneading a liquid crystal polyester and a filler in advance before molding the resin composition to obtain a molded body (hereinafter referred to as a pellet-like composition). It is generally practiced to obtain “composition pellets”. As a method for producing a composition pellet, a liquid crystal polyester and a filler are melted and kneaded, and a molten liquid crystal polyester resin composition is extruded into a string shape to obtain a string composition (strand). A manufacturing method is generally known in which the composition is cooled and solidified and cut to obtain a composition pellets (such a manufacturing method is called a strand method).

However, in a resin composition that is highly filled with a high-dielectric material filler as proposed in Japanese Patent Application Laid-Open No. 2 0 4 -1 6 1 9 5 3 Since it is difficult to obtain the composition pellets, the composition pellets may not be stably obtained. In this document, a production method for tableting with a tableting machine is employed. Such a manufacturing method is relatively complicated and mass production. Is unsuitable and is not suitable for industrial production. The resin composition of the invention of Japanese Patent Application Laid-Open No. 2006-2331 18 is a resin composition capable of obtaining a molded article having excellent dielectric properties even though the filling amount of the high dielectric material filler is small, and the strand tends to be easily obtained. In the direction. However, the compatibility with the strand method is not necessarily sufficient in order to obtain a composition pellets with industrial stability and good productivity.

 Therefore, one of the objects of the present invention is that a resin method using a liquid crystal polyester and a high dielectric material filler can be applied with a strand method suitable for industrial production, and the composition pellets can be stably used. An object of the present invention is to provide a liquid crystal polyester resin composition that can be produced.

As a result of intensive studies, the present inventors have completed the present invention. That is, the present invention comprises a structural unit represented by the following formula (ί), a structural unit represented by the formula (ii), and a structural unit represented by the formula (iii), 2, 6-naphthalene diyl group when the total of the divalent aromatic group represented by Ar ₂ and the divalent aromatic group represented by Ar ₃ is 100 mol%. Liquid crystal polyester (A) 50 to 80% by volume with a melt starting temperature of at least 280 ° C and a melt tension measured at a temperature higher than the flow starting temperature of 1 g or more. ,

Filler made of high dielectric material (B) 20-50% by volume,

A liquid crystal polyester resin composition is provided.

 0

—— o—— Ar 厂 c — (i) o o

c—— ΑΓ ₂ — c — (ii)

o—— Ar ₃ — 0 — (iii) where Αη consists of 2, 6-naphthalene diyl group, 1, 4 1-phenylene group, and 4, 4 ′ 1-bif; ι: diene group Represents a divalent aromatic group selected from the group. Ar ₂ , A r ₃ is independently a divalent group selected from the group consisting of 2,6-naphthalenediyl group, 1,4-phenylene group, 1,3-phenylene group, and 4,4′-biphenylene group. Represents an aromatic group. In addition, in the aromatic group represented by ηη, Ar ₂ or Ar ₃ , a part of the hydrogen atoms bonded to the aromatic ring are a halogen atom, an alkyl group having 1 to 10 carbon atoms, or 6 to 6 carbon atoms. It may be substituted with 20 aryl groups.

 The liquid crystal polyester resin composition of the present invention can be used in various applications that require dielectric properties such as high dielectric properties and low dielectric loss tangents.

 The present invention further provides a molded body using the liquid crystal polyester resin composition, and an antenna having the molded body and an electrode.

 According to the liquid crystal polyester resin composition of the present invention, a composition pellet can be easily produced by a composition pellet production method such as a strand method, which is widely used in this technical field. Since this composition pellet has good operability, a molded product can be easily obtained by injection molding or the like. The molded body using the liquid crystal polyester resin composition of the present invention is used in various applications where high dielectric properties and low dielectric loss tangents are required, particularly for antennas of information communication equipment to which high frequency electromagnetic waves are applied. Since it can be used suitably, it is very useful industrially. BEST MODE FOR CARRYING OUT THE INVENTION

 The present invention provides a liquid crystal polyester resin composition containing 50 to 80% by volume of liquid crystal polyester (A) and 20 to 50% by volume of a filler (B) made of a high dielectric material.

The liquid crystalline polyester used in the present invention is a polyester that exhibits optical anisotropy when melted and can form an anisotropic melt at a temperature of 45 ° C. or lower. More specifically, the liquid crystalline polyester used in the present invention includes a structural unit represented by the following formula (i), a structural unit represented by the formula (ii), and a structural unit represented by the formula (iii). becomes a divalent aromatic group represented by Alpha eta, the total of divalent aromatic groups represented by divalent aromatic group and a r ₃ represented by a r ₂ (hereinafter, "total aromatic When the total of the group is “100 mol%”, the aromatic group contains at least 40 mol% of 2,6-naphthalenediyl group. In addition, the liquid crystal polyester used in the present invention has a flow start temperature of The melt tension measured at 280 ° C or higher and higher than the flow start temperature is 1 g or higher.

 o

—— O—— ΑΓ, —— C (j)

O O

C ~ -Ar ₂ —— C • (H)

0—— Ar ₃ — ο (iii)

Here, Αη is a divalent aromatic group selected from the group consisting of 2,6-naphthalenedyl group, 1,4-phenylene group and 4,4′-biphenylene group, Ar ₂ , A r ₃ is each independently a bivalent group selected from the group consisting of 2,6-naphthalenediyl group, 1,4-monophenylene group, 1.3-phenylene group, and 4,4'-biphenylene group. It is an aromatic group. Further, the divalent aromatic group represented by Αη, Ar ₂ and Ar ₃ may have a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms as a substituent. Good.

Such a liquid crystal polyester comprises a monomer having a 2,6-naphthalenediyl group and another monomer having an aromatic ring, in which the structural unit having a 2,6-naphthalenediyl group is 40 The raw material monomer can be selected and polymerized so as to be at least mol%. A preferable liquid crystal polyester is a liquid crystal polyester in which 2,6-naphthalene diyl group is 50 mol% or more with respect to 100 mol% of total aromatic groups, and more preferably 2,6-naphthalene diyl group is 65 mol%. It is a liquid crystal polyester having a mol% of at least 70, and particularly preferably a liquid crystal polyester having 2,6 mononaphthalenedyl groups of 70 mol% or more. Thus, the liquid crystal polyester containing more 2,6-naphthalenediyl groups as the aromatic group can be obtained by setting the melt tension to 1 g or more as will be described later. This makes it possible to produce the composition pellets stably. In addition, the liquid crystal polyester containing more 2,6-naphthalenediyl groups also has the advantage that the resulting molded article can be further reduced in dielectric loss tangent.

 On the other hand, in the liquid crystal polyester, the total aromatic group total is 100 mol%,

If the 2,6-naphthalenediyl group is less than 40 mol%, the resulting molded article tends to have a large electrostatic tangent.

 The total of the structural unit represented by the formula (i), the structural unit represented by the formula (ii) and the structural unit represented by the formula (iii) constituting the liquid crystalline polyester used in the present invention (hereinafter referred to as “the structural unit represented by the formula (i)”) The total of structural units represented by (i) (hereinafter referred to as “structural units (i)”) is 30 to 80 mol%. The total of structural units represented by (ii) (hereinafter referred to as “structural units (ii)”) is 10 to 35 mol%, and the structural units represented by (iii) (hereinafter “structural units”)

 (iii) J) is preferably 10 to 35 mol%. Liquid crystalline polyesters in which the molar ratio (copolymerization ratio) of the structural unit (i), structural unit (ii), and structural unit (iii) to the total of all structural units is in the above range should exhibit a high degree of liquid crystallinity. In addition to this, it can be melted at a practical temperature, and melt molding becomes easy, which is preferable.

 The liquid crystalline polyester is preferably a wholly aromatic liquid crystalline polyester in that a higher degree of heat resistance is obtained. The structural unit (i), the structural unit (ii) and the structural unit are preferred.

 Those having no structural unit other than (iii) are preferred. Therefore, the molar ratio of the total of structural units (ii) to the total of all structural units is substantially equal to the molar ratio of the total of structural units (iii).

 The molar ratio of the total of the structural units (i) to the total of the structural units is more preferably 40 to 70 mol%, and particularly preferably 45 to 65 mol%. On the other hand, the molar ratio of the total of structural units (ii) and the total molar ratio of structural units (iii) with respect to the total of all structural units is more preferably 15 to 30 mol%, and 17.5 to 27. 5 mol% is particularly preferable.

When the total molar ratio of the structural unit (i), the total molar ratio of the structural unit (ii), and the total molar ratio of the structural unit (iii) are within the above ranges, the liquid crystal polyester Tell has the advantage that it can exhibit a higher degree of liquid crystallinity and can be melted at a more practical temperature, facilitating melt molding.

 The structural unit (i) is a structural unit derived from an aromatic hydroxycarboxylic acid. Examples of the monomer for deriving the structural unit U) include 2-hydroxy-16-naphthoic acid, p-hydroxybenzoic acid, and 4- (4-hydroxyphenyl) benzoic acid. Further, a part of the hydrogen atoms bonded to the benzene ring or naphthalene ring of these monomers are substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms. Monomers can also be used. Among them, a monomer for deriving a structural unit having a 2,6-naphthalenediyl group is 2-hydroxy 6-naphthoic acid.

 The structural unit (i i) is a structural unit derived from an aromatic dicarboxylic acid. Examples of the monomer for deriving the structural unit (ii) include 2,6-naphthalenedicarboxylic acid, terephthalic acid, isophthalic acid, and Bif I diluo 4,4'-dicarboxylic acid. Further, a monomer in which a part of hydrogen atoms bonded to the benzene ring or naphthalene ring of these monomers is substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms. Can also be used. Among them, a monomer for deriving a structural unit having a 2,6 mononaphthalenediyl group is 2,6-naphthalenedicarboxylic acid.

 The structural unit (iii) is a structural unit derived from an aromatic diol. Examples of the monomer for deriving the structural unit (iii) include 2,6-naphthalenediol, hydrated quinone, resorcin, and 4,4′-dihydroxybiphenyl. In addition, a monomer in which a part of hydrogen atoms bonded to the benzene ring or naphthalene ring of these monomers is substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms. Can also be used. Among them, a monomer for deriving a structural unit having a 2,6-naphthalenediyl group is 2,6-naphthalenediol.

As described above, the structural unit (i), the structural unit (ii), or the structural unit (iii) may have any of the above substituents on the aromatic ring (benzene ring or naphthalene ring). . When these substituents are simply exemplified, as the halogen atom, for example, Fluorine atom, chlorine atom, bromine atom, iodine atom are mentioned. Examples of the alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group, etc. These may be linear or branched, and may be alicyclic groups. Examples of the aryl group include aryl groups having 6 to 20 carbon atoms represented by phenyl group, naphthyl group and the like.

 The monomer that derives the structural unit (i), the structural unit (ii), or the structural unit (iii) may be converted into an ester-forming derivative in order to facilitate polymerization in the process of producing the polyester. preferable. The ester-forming derivative means a compound having a group that promotes an ester formation reaction. Specifically, in a monomer having a carboxyl group, the carboxyl group is represented by an acid halide, an acid li, or the like. It is an ester-forming derivative that has been converted to water, and in the case of a monomer having a hydroxyl group, it is an ester-forming derivative in which the hydroxyl group has been converted to an ester using a lower carboxylic acid.

 A known method may be adopted as a method for producing the liquid crystal polyester. A preferred production method includes a method of producing a liquid crystal polyester using an ester-forming derivative obtained by converting a hydroxyl group in a monomer molecule into an ester using a lower carboxylic acid as the ester-forming derivative. Among these, a production method using an ester-forming derivative obtained by converting (acylating) a hydroxyl group of an aromatic hydroxycarboxylic acid and an aromatic diol into an acyl group is preferable. The acylation can usually be carried out by reacting a monomer having a hydroxyl group (aromatic hydroxycarboxylic acid and aromatic diol) with acetic anhydride. The ester-forming derivative thus obtained can be easily produced into a polyester by polycondensation with an aromatic dicarboxylic acid.

As a method for producing a liquid crystal polyester using an ester-forming derivative, for example, a production method described in Japanese Patent Application Laid-Open No. 2 00 2-1 46 0 0 3 can be exemplified. Regarding the production of the liquid crystalline polyester used in the present invention, the application of the production method described in this publication will be briefly described. The monomer that forms the structural unit (i), the structural unit (ii), and the structural unit (iii) can be derived from a monomer that can derive a structural unit having a 2,6-naphthalenediyl group. 40 mol% or less The aromatic hydroxycarboxylic acid for deriving the structural unit (i) and the aromatic diol for deriving the structural unit (iii) are converted to ester-forming derivatives after being converted to ester-forming derivatives. ii) is melt-polymerized with the aromatic dicarboxylic acid to form a relatively low molecular weight liquid crystal polyester (hereinafter sometimes referred to as “prepolymer”). Next, this prepolymer is used as a powder, and this powder is heated for solid phase polymerization. When solid-phase polymerization is used in this manner, the polymerization proceeds more rapidly, and the liquid crystal polyester can be increased in molecular weight, so that the flow start temperature of the obtained liquid crystal polyester can be increased. As will be described later, this solid phase polymerization is also effective for adjusting the melt tension of the liquid crystal polyester.

 In order to make the prepolymer obtained by melt polymerization into powder, the prepolymer may be cooled and solidified and then pulverized by various known pulverization means. The average particle size of the powder is preferably in the range of about 0.05 mm to about 3 mm, and more preferably in the range of about 0.05 mm to about 1.5 mm. If the particle diameter of the powder is in such a range, it is more preferable because the degree of polymerization of the aromatic liquid crystal polyester is promoted, and if it is in the range of about 0.1 mm to about 1 mm, the sintering between the particles is preferable. This is more preferable because it increases the degree of polymerization of the liquid crystal polyester without causing a ring.

 Suitable conditions for the heating conditions in the solid phase polymerization are exemplified below. First, the temperature is raised from room temperature to a temperature that is 20 ° C lower than the flow start temperature of the prepolymer. Although the temperature raising time at this time is not limited, it is preferably within 1 hour from the viewpoint of shortening the reaction time.

 Next, the temperature is raised from a temperature 20 ° C. or more lower than the flow start temperature of the prepolymer to a temperature of 28 ° C. or more. The temperature increase is preferably performed at a temperature increase rate of 0.3 ° C. or less, and a temperature increase rate of about 0.1 to 0.15 ° C. is more preferable. When the temperature rising rate is 0.3 ° C. or less, sintering between powder particles hardly occurs, and therefore, a liquid crystal polyester having a higher degree of polymerization can be produced relatively easily.

In order to further increase the polymerization degree of the liquid crystalline polyester, the reaction may be carried out at a temperature of 28 ° C. or higher, preferably 30 ° C. to 400 ° C. for 30 minutes or longer. preferable. In particular, from the viewpoint of improving the thermal stability of liquid crystal polyester, The reaction is preferably performed at a reaction temperature of 280 to 350 ° C for 30 minutes to 30 hours, and more preferably at a reaction temperature of 285 to 340 ° C for 30 minutes to 20 hours. Such heating conditions can be optimized as appropriate depending on the type of monomer used in the production of the liquid crystalline polyester.

If solid-state polymerization is used as described above, the flow start temperature of the liquid crystal polyester can be set to 280 ° C. or higher in a relatively short time. A liquid crystal polyester having such a flow start temperature is obtained according to the present invention. When applied to the liquid crystal polyester resin composition, the obtained molded product has a high heat resistance. The flow start temperature is a capillary rheometer equipped with a die with an inner diameter of 1 mm and a length of 1 Omm, and a heating rate of 4 ° CZ under a load of 9.8 MPa (100 kg / cm ² ). Means the temperature at which the melt viscosity shows 4800 Pa s (48000 boise) when the liquid crystal polyester is extruded from the nozzle in minutes, and the flow start temperature represents the molecular weight of a liquid crystal polyester known in the art Index (see Naoyuki Koide, “Liquid Crystalline Polymer Synthesis / Molding-Application 1”, pages 95-105, CMC, published on June 5, 987. In the present invention, the flow start temperature is As a device to measure, a flow characteristic evaluation device “Flow Tester CFT-500DJ” manufactured by Shimadzu Corporation is used.) When the liquid crystal polyester resin composition of the present invention is used for manufacturing an antenna substrate, an electrode forming process is used. Better heat resistance against In order to achieve this, the flow starting temperature of the liquid crystalline polyester is more preferably 290 ° C. or higher, and further preferably 295 ° C. or higher, while the antenna substrate is molded in a practical temperature range. From this point of view, the flow start temperature is preferably 380 ° C or lower, more preferably 350 ° C or lower.

 Further, in the measurement of the flow start temperature, the shape of the liquid crystal polyester used as the sample to be measured is not limited to powder, but the liquid crystal polyester may be formed into a pellet shape by a known method.

As described before, the liquid crystal polyester may be made into a pellet as a sample to be measured for the flow start temperature measurement. However, the liquid crystal polyester having such a pellet shape can also be used for the melt tension measurement described later. The production method will be briefly described. Examples of the extruder to be used include, for example, a single-screw or multi-screw extruder, and a twin-screw extruder, a Banbury type kneader, and a roll-type kneader are preferable. Pellets are obtained by melting liquid crystal polyester in the temperature range from 10 ° C lower than T p to 1 oo ° c higher than T p, starting from its flow start temperature T p [° C]. be able to. From the viewpoint of sufficiently preventing thermal deterioration of the liquid crystalline polyester, it is preferable to melt in a temperature range from 10 ° C lower than Tp to 70 ° C higher than Tp. It is more preferable to melt in the temperature range from 0 ° C lower to 50 ° C higher than Tp.

 The liquid crystalline polyester used in the present invention has a melt tension of 1 g or more measured at a temperature higher than the flow start temperature. A preferred liquid crystal polyester is a liquid crystal polyester having a melt melt of 1.5 g or more, more preferably 2 g or more of a liquid crystal polyester. In particular, a liquid crystal polyester having a melt tension of 1 g or more measured at a temperature about 25 ° C. higher than the flow start temperature is a liquid crystal polyester resin composition using a relatively large amount of a highly-inductive material filler as described later. However, the composition pellets tend to be manufactured stably. The melt tension here refers to a capillograph filled with liquid crystal polyester (pelletized liquid crystal polyester), a cylinder barrel diameter of 1 mm 0, a piston extrusion speed of 5. O mm, and a variable speed winder. It means the tension (g) when the sample is taken up in a filament shape while automatically accelerating and breaks, and several points of melt tension are measured at a temperature higher than the flow start temperature of the liquid crystalline polyester used for measurement. If the melt tension is 1 g or more at one point, it is defined as “liquid crystalline polyester having a melt tension of 1 g or more measured at a temperature higher than the flow start temperature” in the present invention. To do.

 Here, an example is given and demonstrated about the method of manufacturing liquid crystalline polyester whose melt tension measured at the temperature higher than a flow start temperature is 1 g or more.

In order to obtain a liquid crystal polyester having a high melt tension, it is effective to increase the molecular weight of the liquid crystal polyester and to introduce a structural unit having a smaller molecular volume. In the former case, as described above, from the viewpoint of obtaining a molded article with higher heat resistance, The liquid crystal polyester may be manufactured by combining the flow start temperatures of 280 ° C or higher.

 In order to introduce the latter structural unit having a small molecular volume, introduction of a monocyclic aromatic group is effective. From this point of view, as structural unit (i), structural unit derived from p-hydroxybenzoic acid, as structural unit (ii), structural unit derived from terephthalic acid and Z or isophthalic acid, structural unit (iii) As an example, a method for improving the amount of introduction of a structural unit derived from an aromatic diol selected from hydride quinone and resorcin is cited. In addition, from the viewpoint of obtaining a liquid crystal polyester having a higher flow starting temperature, the amount of structural units having low flexibility is preferred, so that as structural unit (ii), structural units derived from terephthalic acid, The structural unit (iii) is preferably a structural unit derived from hydroquinone. In addition, it has been described that the aromatic ring in these structural units may have a substituent, but in terms of introducing a structural unit having a small molecular volume, the structural unit having no substituent is introduced. Input is preferred.

 On the other hand, the liquid crystalline polyester used in the present invention needs to contain 2,6-naphthalenediyl groups in an amount of 40 mol% or more based on the total aromatic groups, and has a structure having 2,6-naphthalenediyl groups. It is necessary to control the unit and the structural unit having a monocyclic aromatic group.

Specifically, when a combination of structural units constituting a more preferable liquid crystal polyester is described, the structural unit (i-a) derived from 2-hydroxy-16-naphthoic acid is 40 to 75 as the structural unit (i). The total of the structural unit derived from 2,6-naphthalenedicarboxylic acid (ii-a) and the structural unit derived from terephthalic acid (ii 1 b) is 12.5. ~ 30 mol%, as structural unit (iii), has 12.5 to 30 mol ⁰ 6 structural unit (iii-a) derived from hydroquinone [where structural unit (i-a), (ii a), (ii-1b) and (iii-1a) are 100 mol%], and in structural unit (ii), the molar ratio of (ii-1a) to (ii-1b) is , (Ii—a) / [(ii—a) + (ii-b)} ≥0.5. More preferred liquid crystalline polyesters are those in which (ί — a) is 40 to 60 mol% with respect to the sum of the structural units (i 1 a), (i ia), (i i- b) and (i ii— a), (Ii-a) force << 1 4.5-29. 5 mol%, the sum of (ii-a) and (ii-b) is 15-30 mol%, (iii-a) is 15-5 And (ii) in the structural unit, the molar ratio of the structural unit between (ii—a) and (ii-1b) is (ii—a) /

{(i ia) + (ii-b)} A liquid crystalline polyester satisfying the relationship of ≥0.6, and particularly preferably (i — a) is 50 to 60 mol%, and (ii—a) is 15 ˜24.5 mol%, the sum of (ii—a) and (ii—b) is 20-25 mol%, (iii-a) is 20-25 mol%, and the structure of (ii) In the unit, the copolymerization ratio of the structural units (ii-1a) and (ii-1b) satisfies the relationship (ii—a) / {(i ia) + (ii—b)} ≥0.6 Liquid crystal polyester.

 Then, by using each monomer capable of deriving such a combination of structural units, melt polymerization and solid phase polymerization are performed, and the flow start temperature is set to 280 ° C or higher, preferably 295 ° C or higher. This makes it possible to produce liquid crystal polyester that can achieve a tension of 1 g or more.

 The filler (B) made of a high dielectric material used in the present invention (hereinafter sometimes referred to as “high dielectric filler (B)”) is a known filler applied to a high dielectric composition. Can be used. Specifically, a filler as exemplified in JP-A-2004-307607 (paragraph [0030]), that is, a titanium dioxide system, a barium titanate system, a barium titanate zirconate system, a titanate stopper Nitium, calcium titanate, bismuth titanate, magnesium titanate, barium neodymium titanate, barium tin titanate, magnesium barium titanate, barium magnesium tantalate, lead titanate , Lead zirconate, lead zirconate titanate, lead niobate, lead magnesium niobate, lead nickel niobate, lead tungstate, calcium tungstate and lead magnesium tungstate Fillers made of high dielectric materials are applicable.

Among the high dielectric material fillers exemplified above, a titanium ceramic filler is preferable from the viewpoint of obtaining a molded body having a high dielectric constant. "Titanium ceramics The “filler” is a filler made of ceramics having titanium as a constituent element component, and specific examples of the ceramics include titanium oxides and metal titanates. Here, the metal titanate refers to a metal titanate selected from a group consisting of barium, strontium, bismuth, lanthanum, neodymium, samarium, aluminum, calcium and magnesium, or a plurality of metals selected from such a group. There may be mentioned titanates formed by solid solution.

Further, from the viewpoint of obtaining a molded body having a lower dielectric loss tangent, among the titanium-based ceramic fillers, T i 0 ₂ , B a T i 0 ₃ , S r T i 0 ₃ , C a T i 0 ₃ , M g T i 0 ₃ , B a S r T i ₂ 0 ₆ , B a N d ₂ T i ₄ 0 ₁₂ , B a N d ₂ T i ₅ 0 ₁₄ , B a B i ₂ N d ₂ T i 0 _A filler consisting of ₉ etc. is preferred, T i 0 ₂ , B a T i 0 ₃ , S r T i 0 ₃ , B a S r T i ₂ 0 ₆ , B a N d ₂ T i ₄ 0 ₁₂ and B group force consisting of _{a N d 2 T i 5 0} 14, filler made of titanium based ceramics selected et more preferably. The titanium-based ceramic filler used in the present invention mainly contains such titanium-based ceramics, and does not exclude unintentionally contained impurities, and has been subjected to a surface treatment as described later. May be.

 These high dielectric material fillers may be used in combination of two or more. These high dielectric material fillers may be surface-treated with a surface treatment agent such as a titanate coupling agent, an aluminum coupling agent, or a silane coupling agent.

 Next, a suitable titanium-based ceramic filler will be described in detail.

 The titanium-based ceramics exemplified above can be produced by known means. For example, a metal carbonate selected from the group consisting of barium, strontium, bismuth, lanthanum, neodymium, aluminum, calcium and magnesium, and titanium oxide are mixed and baked, then crushed and crushed as necessary Alternatively, a titanium-based ceramic filler can be manufactured by performing operations such as classification.

Further, a titanium-based ceramic filler that can be easily obtained from the market may be used. From the viewpoint of availability and economy, a filler made of T i 0 ₂ or Ba T i 0 ₃ is preferable. As a specific example of a commercially available product, a filler made of B a T i 0 ₃ is Γ Γ Ρ Β Τ-1 ”manufactured by Fuji Titanium Industry Co., Ltd. wear. In addition, as a filler consisting of T i 0 ₂ , “CR— 6” manufactured by Ishihara Sangyo Co., Ltd.

OJ, “CR-58”, “CR-97”, “Taipeke PF R404J” and “SR-1 J” manufactured by Sakai Chemical Industry Co., Ltd. The titanium-based ceramics may be either single crystal or polycrystalline, and the crystal form is not limited.

 The shape of the high dielectric material filler is not limited, and may be any of fine powder, fiber, and plate. In the method for preparing a liquid crystal polyester resin composition described later, It is preferable to select a filler having a shape that can be well dispersed. Thus, the liquid crystal polyester resin composition using the filler that can be well dispersed in the heated melt has a high dielectric material filler in the molded product when the molded product is obtained by molding this resin composition. It exists almost uniformly and tends to exhibit good properties related to the filler. From the viewpoint of operability, the titanium ceramic filler is preferably finely powdered. The fine powdery filler is more preferably an average particle size of 0.01 to 100 μm, and further preferably 0.1 to 20 / m. Such an average particle diameter is obtained by external observation with an electron microscope when the average particle diameter is 2 O im or less, and when the average particle diameter exceeds 20 m, a laser single diffraction light scattering method is used. Is required.

In the case of a fine powder titanium-based ceramic filler with an average particle size of 20 βm or less, a method for obtaining the average particle size will be briefly described. First, the external appearance of a titanium ceramic filler was measured using a scanning electron microscope (SEM) and SEM photographs were measured. The obtained SEM photographs were then analyzed using an image analyzer (eg, “Luzex IIIUJ” manufactured by Nireco Corporation). Then, by plotting the particle amount (%) in each particle size section of the primary particles, a distribution curve is obtained, and from the accumulated distribution curve, the particle size having a cumulative degree of 50% is taken as the average particle size. From the viewpoint of improving mechanical strength such as impact strength, it is preferable that the average particle size of the titanium ceramic filler is 0.23 to 5 jum, and a fine particle size of 0.25 to 1.5 m. More preferably, it is in the form of powder, and more preferably in the form of fine powder of 0.26 to 0.30 jUm. From the viewpoint of improving the mechanical strength such as bending strength, it is preferable to use a fibrous titanium ceramic filler. In such a fibrous titanium-based ceramic filler, the number average fiber length is preferably more than 0.5 jum and not more than 1 O im, and the number average fiber diameter is not less than 0.1 / m and not more than 1 jum, Aspect ratio (Number average fiber length Z Number average fiber diameter) More preferably, it is in the form of 2 or more, the number average fiber length is 1 jum or more and 10 m or less, and the number average fiber diameter is 0.1. It is more preferably 0.5 / m or less and a fibrous form with an aspect ratio of 3 or more. Such number-average fiber length and number-average fiber diameter are determined by appearance observation with a scanning electron microscope (SEM).

 The titanium-based ceramic fillers that can be easily obtained from the above-exemplified market are classified according to their shapes. The fine powdered titanium-based ceramic fillers are “HP BT-1 J”, “CR-60”, “ “CR-58”, “CR-97J”, “SR-1 J” are exemplified, and “Taipaque PF R404” is exemplified as the fibrous titanium ceramic filler.

 The liquid crystal polyester resin composition of the present invention may contain an additive such as a reinforcing agent depending on necessary properties as long as the object of the present invention is not significantly impaired.

 Here, examples of additives include fibrous reinforcing agents such as glass fiber, silica alumina fiber, alumina fiber, and carbon fiber; acicular reinforcing agents such as aluminum borate whisker and titanic acid re-wiss whisker; glass Inorganic fillers such as beads, talc, my strength, graph eye candy, wollastonite, dolomite candy; mold release improvers such as fluororesins and metal stones; colorants such as dyes and pigments; antioxidants; thermal stability Agents; ultraviolet absorbers; antistatic agents; surfactants and the like. Two or more of these additives may be used in combination.

It is also possible to use additives having an external lubricant effect, such as higher fatty acids, higher fatty acid esters, higher fatty acid metal salts, and fluorocarbon surfactants. In addition, if the amount is small, thermoplastic resins other than liquid crystal polyester (for example, polyamide, crystalline polyester, polyethylene sulfide, polyether ketone, polycarbonate, polyphenylene ether and its modified products, polysulfone, Ethersulfone, polyetherimide, etc.) and thermosetting resins (for example, phenol) Resin, epoxy resin, etc.). When using a thermoplastic resin or thermosetting resin other than liquid crystal polyester, it is necessary to select the type and amount of addition so as not to impair the liquid crystal polyester's liquid crystal properties and moldability. is there.

 The liquid crystal polyester resin composition used in the present invention is obtained by mixing the liquid crystal polyester (A), the high dielectric material filler (B), and other components such as additives used as necessary.

 In the liquid crystal polyester resin composition of the present invention, the content ratio of the liquid crystal polyester (A) and the high dielectric material filler (B) is such that the dielectric properties of the high dielectric material filler used are sufficiently expressed, and the melt processability is good. It is determined in consideration of such balance. Specifically, the high dielectric material filler is preferably 20 to 50% by volume with respect to 100% by volume of the total amount of liquid crystal polyester and high dielectric material filler to be blended. More preferably, the content ratio is 2 2 to 4 5% by volume. Next, a method for producing a composition pellets according to the above-mentioned Sland method will be described.

 In the preparation method for obtaining the liquid crystal polyester resin composition of the present invention, the blending means is not particularly limited as long as each raw material component can be melt-kneaded. Specifically, liquid crystal polyester (A) and high dielectric material filler (B), a method of supplying other components separately added to the melt mixer as needed, these raw material components in a mortar, Henschel mixer And a method of premixing using a ball mill, a ribbon blender, etc., and then feeding to a melt mixer. By such melt kneading (thermal melting), the liquid crystal polyester resin composition forms a heated melt.

The temperature condition in the melt-kneading can be appropriately optimized based on the flow start temperature T p [° C] of the liquid crystal polyester (A) used. Preferably, the temperature range is from 10 ° C below T p to 100 ° C above T p, more preferably from 10 ° C below T p to 70 ° C below T p The temperature range is a high temperature, and more preferably, the temperature range is 10 ° C lower than Tp to 50 ° C higher than Tp. If two or more types of liquid crystalline polyester (A) are used, For the mixture of two or more liquid crystal polyesters, the flow start temperature is obtained by the method described above, and the flow start temperature may be used as a base point.

 The heated melt of the liquid crystalline polyester resin composition obtained by melt-kneading is extruded into a string shape by, for example, a single-screw or multi-screw extruder, preferably a twin-screw extruder, a Banbury set kneader, a roll kneader or the like. After forming the string-like composition, the string-like composition (strand) is cooled and solidified, and when it is cut, it can be added to the composition pellets by a series of operations. Further, it is also possible to use a hot force method in which the strand is cut and processed into a pellet by a die cutter immediately after being discharged from the die of the extruder without being cooled and solidified. However, when the strand method and the hot-cut method are compared from the viewpoint of productivity, the Strand method is advantageous in terms of better productivity. As described above, the method for preparing the composition pellets using a single screw or twin screw extruder facilitates operability because it can continuously perform from melt-kneading to pelletizing.

 In the liquid crystal polyester resin composition of the present invention, even if the high dielectric material filler is relatively high filled, the pellet method is a known pellet manufacturing means represented by the hot cut method. Can be manufactured stably and with high productivity.

 The shape of the composition pellets obtained as described above may be cylindrical or prismatic. The cross-sectional shape may be any of a circle, a substantially circle, an ellipse, and a star. In general, it is better to use a columnar composition, Perez®. This cross-sectional shape can be appropriately optimized depending on the shape of the extrusion port of the extruder.

 The length of the composition pellets is appropriately selected according to the molding method to be described later, but it is preferably 0.1 to 1 O mm on average, and 1 to 5 mm long. More preferable. The ratio of the diameter Z length of the pellets is preferably in the range of 0.1 to 10, more preferably in the range of 0.2 to 3, and particularly preferably in the range of 0.3 to 1.

The pellet-like liquid crystal polyester resin composition thus obtained can be applied to various conventional molding methods. As the molding method, for example, melt molding such as injection molding or press molding is preferable, and injection molding is particularly preferable. As injection molding, Specific examples include general injection molding, injection compression molding, two-color molding, and sandwich molding. Among these, general injection molding and injection compression molding are preferable. In any of these forming methods, the liquid crystal polyester resin composition of the present invention can be obtained as a composition pellets having excellent operability, so that it can be easily supplied continuously to a molding machine. It is also good in terms of storage.

 The molded product obtained by using the liquid crystalline polyester resin composition of the present invention is a test method of ASTM D790, although it is relatively filled with a high dielectric material filler.

According to (Method 1 three-point bending method), the measured bending strength is 1 OOMPa or more, and it becomes possible to obtain a molded article with extremely high mechanical strength.

 The molded product obtained using the liquid crystalline polyester resin composition of the present invention has a measured impact strength according to the test method of ASTM D256 (no notch) even though the high dielectric material filler is filled relatively high. However, it is possible to obtain a molded article having an extremely high impact strength.

 As described above, the liquid crystalline polyester (A) used in the present invention contains a specific amount of 2.6-naphthalenediyl group and has a flow start temperature of 280 ° C. or higher and a temperature higher than the flow start temperature.卜 The tension is 1 g or more, so it has excellent heat resistance and mechanical strength. The liquid crystal polyester resin composition of the present invention comprises a high dielectric material filler by molding a molded body as a composition pellets

Even when (B) is filled relatively high, the dispersibility of the high dielectric material filler (B) is improved, and the high dielectric material filler (B) is well suppressed from agglomerating in the molded body. Can do. Such a molded product can be obtained by maintaining the excellent mechanical strength of the liquid crystalline polyester itself and having an extremely excellent mechanical strength.

In addition, the molded product obtained using the resin composition of the present invention exhibits a sufficient dielectric effect, which is related to a high dielectric material filler, particularly a titanium ceramic filler, and has a measurement temperature of 23 ° C. and a frequency of 1 it is also possible to dielectric constant in GH _Z expresses six or more. In addition, in the molded body that has been molded in advance with the composition pellets, the high-dielectric material filler is substantially uniformly present in the molded body, and the dielectric characteristics partially vary in the molded body. Such inconvenience can be avoided very well. By such a molding method, a mold having a desired shape and size can be obtained by appropriately optimizing the mold and the like. As described above, the molded body has excellent dielectric properties and high mechanical strength, and further retains the high degree of heat resistance of liquid crystalline polyester, so it is a member for manufacturing antennas, especially for antennas. »Used suitably for the body.

 The antenna substrate can be manufactured by etching or the like as necessary to form electrodes (radiation electrode, ground electrode). As a means for forming a conductive layer that can serve as an electrode, known methods such as metal plating, sputtering, ion plating, vacuum evaporation, and soldering are employed. Alternatively, the metal foil processed into the desired electrode shape may be bonded or pressure-bonded with an adhesive or the like. After the metal foil is bonded or pressure-bonded to the surface of the molded body in advance, the desired shape is obtained. A metal foil bonded or pressed may be patterned.

 Since the antenna substrate thus obtained has extremely excellent dielectric characteristics and mechanical strength, the antenna substrate is easier to miniaturize than conventional ones. For example, for wireless LAN such as Bluetooth, mobile phone's PHS or mopile equipment, It is particularly suitable for use as an antenna for GPS (Global Positioning System), ETC (Electric Rick! ^ One Collection System), and satellite communications. As described above, the antenna obtained using the liquid crystal polyester resin composition of the present invention is excellent in durability against the external environment due to high mechanical strength, high heat resistance, etc., and thus can be suitably used as an antenna for outdoor installation. It is. In addition, due to the effect of miniaturization due to its excellent dielectric properties, it is extremely excellent as an antenna for automobiles or antennas for portable devices.

 Example

 EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

 In the present invention, the following measurements were performed.

 (Flow start temperature measurement method)

Using a flow tester (manufactured by Shimadzu Corporation, “CFT-500 type”), fill a capillary rheometer with a sample size of about 2 g and a die with an inner diameter of 1 mm and a length of 10 mm. To fill. 9. Temperature at which melt viscosity is 4800 Pa-s (48000 boise) when liquid crystalline polyester is extruded from the nozzle at a heating rate of 4 ° C under a load of 8 MPa (100 kg / cm ² ) Was defined as the flow start temperature.

 (Melt tension measurement)

 Using Capillograph 1 B type (manufactured by Toyo Seiki Seisakusho), about 1 O g of sample was charged, cylinder barrel diameter 1 mm0, piston extrusion speed was 5. OmmZ, variable speed The sample was taken up into a thread and the tension (g) when it was broken was measured.

 (Bending strength)

 After granulating the liquid crystal polyester resin composition and drying the resulting composition pellets at 120 ° C for 3 hours, the cylinder temperature was 350 using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., PS40E5AS E type). A test piece (sample) having a length of 1 2 7 mm, a width of 1 2.7 mm, and a thickness of 6.4 mm was formed at a mold temperature of 1 ° C. and a mold temperature of 30 ° C. Then, according to the test method of ASTMD790, the bending strength of these samples was measured.

(Solder foam test)

 After granulating the liquid crystal polyester resin composition and drying the resulting pellets for 3 hours at 120 ° C, using an injection molding machine (PS40E5ASE, manufactured by Nissei Plastic Industry Co., Ltd.), cylinder temperature 350 ° C, mold temperature 1 30 ° C, JISK 71 1 31

Samples of (1/1) dumbbell (thickness 1.2 mm) were molded. The obtained sample was immersed in 260 ° C H 60 A solder (60% tin, 40% lead) for 60 seconds. The sample was then pulled up and checked for foaming and swelling.

 (Impact strength)

After granulating the liquid crystal polyester resin composition and drying the resulting pellet at 120 ° C for 3 hours, the cylinder temperature is 350 ° C using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., PS40E5ASE type). C. Molded at a mold temperature of 1 30 ° C to produce a compact with a length of 1 2 7 mm, a width of 1 2.7 mm, and a thickness of 6.4 mm. This molded body was cut to a length of 64 mm, a width of 12.7 mm, and a thickness of 6.4 mm. Sample). The impact strength of these samples was measured according to the test method of AS TMD 256 (no notch).

Synthesis example 1

 In a reactor equipped with a stirrer, torque meter, nitrogen gas inlet tube, thermometer and reflux condenser, 2-hydroxymono-6-naphthoic acid 1 034. 99 g (5.5 mol), bidroquinone 272. 52 g (2.475 mol, 0.225 mol excess charge), 2,6-Naphthalenedicarboxylic acid 378.33 g (1.75 mol), terephthalic acid 83.07 g (0.5 mol), acetic anhydride 1 226. 87 g (12.0 mol) and 0.17 g of 1-methylimidazole as a catalyst were added, and the mixture was stirred at room temperature for 15 minutes, and then heated with stirring. When the internal temperature reached 145 ° C, the mixture was stirred for 1 hour while maintaining the same temperature.

 Next, the temperature was raised from 145 ° C. to 3 10 ° C. over 3 hours and 30 minutes while distilling off distilling by-product acetic acid and unreacted acetic anhydride. A liquid crystal polyester was obtained by incubating at the same temperature for 3 hours. The obtained liquid crystal polyester was cooled to room temperature and pulverized by a pulverizer to obtain a liquid crystal polyester powder (prepolymer 1) having a particle diameter of about 0.1 to 1 mm. The flow initiation temperature of this prepolymer 1 was measured using a flow tester and found to be 267 ° C.

Synthesis example 2

 Prepolymer 1 obtained in Synthesis Example 1 was heated from 25 ° C to 250 ° C over 1 hour, then heated from the same temperature to 293 ° C over 5 hours, and then at the same temperature for 5 hours The mixture was kept warm and subjected to solid phase polymerization. After solid phase polymerization, the liquid crystal polyester was obtained in the form of powder when cooled. This liquid crystal polyester is designated as L C P 1. The flow initiation temperature of L CP 1 was measured using a flow tester and found to be 317 ° C. Synthesis example 3

The prepolymer 1 obtained in Synthesis Example 1 was heated from 25 ° C to 250 ° C over 1 hour, then heated from the same temperature to 310 ° C over 10 hours, and then at the same temperature for 5 hours. The mixture was kept warm and subjected to solid phase polymerization. Upon cooling after solid phase polymerization, liquid crystal polyester was obtained in powder form. This liquid crystal polyester is designated as LCP 2. LC obtained When the flow start temperature was measured for P 2 using a flow tester, 33

3 ° C.

LCP 1 and LCP 2 obtained in Synthesis Examples 1 to 3 were obtained by calculating the copolymerization mole fraction from the molar ratio of the monomer used. Structural unit (i): Structural unit (ii): Structural unit The ratio of (iii) is 55. mol%: 22.5 mol%: 22.5 mol ⁰ / o. This can be expressed as the content ratio of 2,6-naphthalenediyl group to the total aromatic group total.

2. 5 mol%.

Synthesis example 4

 In the same reactor as in Synthesis Example 1, 2-hydroxy-6-naphthoic acid 987.95 g (5.25 mol), 4,4′-dihydroxybiphenyl 486.47 g (2.6 1 2 mol, 0. 237 molar excess charge), 2,6-Naphthalenedicarboxylic acid 51

3. 45 g (2.375 mol), acetic anhydride 1 1 74.04 g (1 1.5 mol) and 1-methylimidazole 0.194 g as catalyst were added and stirred at room temperature for 15 minutes Then, the temperature was raised while stirring. When the internal temperature reached 145 ° C, the mixture was stirred for 1 hour while maintaining the same temperature, and 5.83 g of 1-methylimidazole as a catalyst was further added.

 Next, the temperature was raised from 145 ° C. to 3 10 ° C. over 3 hours and 30 minutes while distilling off distilling by-product acetic acid and unreacted acetic anhydride. A liquid crystalline polyester was obtained by incubating at the same temperature for 2 hours. The obtained liquid crystalline polyester is cooled to room temperature and pulverized by a pulverizer to obtain a liquid crystalline polyester powder (prebolimer 2) having a particle size of about 0.1 to 1 mm using a flow tester. The flow starting temperature was measured and found to be 273 ° C.

 The resulting prepolymer 2 was heated from 25 ° C to 250 ° C over 1 hour, then heated from the same temperature to 300 ° C over 10 hours, and then maintained at the same temperature for 12 hours. Solid state polymerization was carried out by heating. When cooled after solid phase polymerization, liquid crystalline polyester was obtained in powder form. This liquid crystal polyester is designated as LCP 3. The flow initiation temperature of L CP 3 measured using a flow tester was 324 ° C.

Synthesis example 5 The temperature of Prevolima 1 obtained in the same manner as in Synthesis Example 4 was raised from 25 ° C to 250 ° C over 1 hour, then from 325 ° C to 325 ° C over 10 hours, and then Solid-state polymerization was carried out at the same temperature for 12 hours. Upon cooling after solid phase polymerization, liquid crystal polyester was obtained in powder form. This liquid crystal polyester is designated as LCP 4. The flow initiation temperature of LCP4 was measured using a flow tester and found to be 34 9 ° C.

LCP 3 and LCP4 obtained in Synthesis Examples 4 to 5 are based on the molar ratio of the monomers used, and the copolymerization mole fraction is structural unit (i) _: structural unit (ii): structural unit

 The ratio of (iii) is 52.5 mol%: 23.75 mol%: 23.75 mol% This is expressed in terms of the content ratio of 2,6-naphthalenediyl group to the total of all aromatic groups. 3 mol%.

Synthesis example 6

 In the same reactor as in Synthesis Example 1, 91 g (6.6 mol) of p-hydroxybenzoic acid, 409 g (2.2 mol) of 4,4′-dihydroxybiphenyl, and 91 of isophthalic acid were mixed. The mixture was stirred using 1 g (0.55 mol), 274 g (1.65 mol) of terephthalic acid and 1235 g (12.1 mol) of anhydrous acetic acid. Next, 0.17 g of 1-methylimidazole was added and the inside of the reactor was sufficiently replaced with nitrogen gas. Then, the temperature was raised to 150 ° C. over 15 minutes under a nitrogen gas stream, and the temperature was maintained. Reflux for 1 hour. Thereafter, 1.7 g of 1-methylimidazole was added, and the temperature was raised to 320 ° C over 2 hours and 50 minutes while distilling off the by-product acetic acid to be distilled and unreacted acetic anhydride. The time at which it was observed was regarded as the end of the reaction, and the contents were taken out. The obtained liquid crystalline polyester was cooled to room temperature and pulverized with a pulverizer to obtain a liquid crystalline polyester powder (prepolymer 3) having a particle size of about 0.1 to 1 mm.

 The flow starting temperature of this Prebomer 3 was measured using a flow tester and found to be 257 ° C.

The obtained Prebomer 3 was heated from 25 ° C to 250 ° C over 1 hour, then heated from the same temperature to 285 ° C over 5 hours, and then kept at that temperature for 3 hours to solidify. Phase polymerized. When cooled after solid state polymerization, liquid crystalline polyester is obtained in powder form. It was. This liquid crystal polyester is designated as LCP 5. The flow initiation temperature of LCP 5 measured using a flow tester was 327 ° C.

Synthesis example 7

 Prebomer 3 obtained in the same manner as in Synthesis Example 6 was heated from 25 ° C to 250 ° C over 1 hour, then heated from the same temperature to 290 ° C over 5 hours, and then at the same temperature. Incubated for 3 hours for solid phase polymerization. Upon cooling after solid phase polymerization, liquid crystal polyester was obtained in powder form. This liquid crystal polyester is designated as LCP 6. The flow initiation temperature of LCP 6 was measured using a flow tester and found to be 336 ° C.

 LCP 5 and LCP 6 obtained in Synthesis Examples 6 to 7 can be obtained by calculating the copolymerization mole fraction from the molar ratio of the monomers used. Structural unit (i): Structural unit (ii): Structural unit ( The ratio of iii) is 60 mol%: 20 mol%: 20 mol%. Since the monomer used here does not use a monomer having a 2,6-naphthalenediyl group, the content ratio of the 2,6-naphthalenediyl group to the total aromatic groups is 0 mol%.

Reference example 1 ~

Melt tension was measured for the liquid crystal polyesters obtained in Synthesis Examples 1-7. First, using 500 g of liquid crystal polyester, it was granulated by a twin screw extruder (Ikegai Iron Works Co., Ltd. “PCM-30”) at a temperature about 10 ° C higher than the flow start temperature of each liquid crystal polyester. After the subsequent flow start temperature is measured by the above-mentioned method, the melt tension measurement is carried out by changing various measurement temperatures in the temperature range higher than the flow start temperature, and within the obtained melt tension. The maximum value was determined. We also determined the critical temperature at which the sample could not be drawn into a filament and measurement of melt tension was not possible. The results are shown in Table 1. table 1

 In Prebolimer 1 obtained in Synthesis Example 1, when the measurement temperature was 300 ° C. or less, no land could be formed. In addition, when the measurement temperature was 310 ° C or higher, the resin liquefied rather than formed a strand and melt tension could not be measured. Melt tension measurement was attempted even at a measurement temperature of 300 to 310 ° C, but the melt tension could not be calculated because the obtained strand was easily broken.

In LCP 1, the melt tension was 1. Og or more at the measurement temperatures of 310 ° C, 320 ° C and 330 ° C. In LCF ³ 2, main belt tension was measured at a measurement temperature of 330 ~ 360 ° C is was both 1. O g or more. LCP3 and LCP4 had a melt tension of less than 1. O g at a measurement temperature of 360 ° C or lower, and the melt tension could not be measured in the temperature range higher than that. LCP 5 and LCP 6 had a melt tension of 1.0 g or more at a measurement temperature of 350 ° C.

Example 1

As a high dielectric material filler, a filler (HPBT-1 manufactured by Fuji Titanium Industry Co., Ltd.) made of barium titanate (Ba T i 0 ₃ ) was used. 2 ratio (volume ratio) (mixed powder total 4. O kg), using a twin screw extruder (Ikegai Iron Works Co., Ltd. rpCM-30)) with a melting temperature of 340 ° C Attempted pelletization by the Sakai Land method. The strand can be obtained The number of strand breaks between the starting point and the ending point, with the starting point when 0.5 kg of mixed powder is used and the end point when using 3 O kg of mixed powder. By counting (number of strand breaks), the ease of obtaining a strand was determined. The results are shown in Table 2. In this example, no strand break was observed, and it was found that a strand could be stably obtained (number of strand breaks: 0). Examples 2-3

 Using the same high dielectric material filler as that used in LCP 1 obtained in Synthesis Example 2 and Example 1, using the same ratio as shown in Table 2, the same experiment as in Example 1 was performed to break the strand. The number of times was calculated. The results are shown in Table 2. In Example 2, strand breakage was not observed, and it was found that strands were stably obtained (number of strand breaks: 0). On the other hand, in Example 3, a slight strand breakage (strand breakage number: 3 times) was recognized, but there was no problem in practical use. Example 4

 Using the same high dielectric material filler as that used in LCP 2 obtained in Synthesis Example 3 and Example 1, and using the proportions shown in Table 2, the same experiment as in Example 1 was performed to break the strand. The number of times was calculated. The results are shown in Table 2. Also in this example, strand breakage was not recognized, and it was found that strands were stably obtained (number of strand breaks: 0).

Example 5

As a high-dielectric material filler, a filler made of titanium oxide (T i 0 ₂ ) (CR- 60, manufactured by Ishihara Sangyo Co., Ltd., average particle size 0.2 1 ju m) was used. The number of strand breaks was determined by performing the same experiment as in Example 1 except that 1 and the proportions shown in Table 2 were blended. The results are shown in Table 2. Also in this example, no strand break was observed, and it was found that strands could be stably obtained (number of strand breaks: 0).

Example 6

It was obtained in Synthesis Example 2 using a filler made of titanium oxide (T i 0 ₂ ) as a high dielectric material filler (CR-58, manufactured by Ishihara Sangyo Co., Ltd., average particle size 0.28 jum). The same experiment as in Example 1 was conducted except that LCP 1 and the ratio shown in Table 2 were blended. The number of strand breaks was determined. The results are shown in Table 2. Also in this example, no strand break was observed, and it was found that strands could be stably obtained (number of strand breaks: 0).

Example 7

As a high dielectric material filler, a filler (CR-97 manufactured by Ishihara Sangyo Co., Ltd., average particle size of 0.25 jum) made of titanium oxide (Τ 0 ₂ ) was used, and LCP 1 obtained in Synthesis Example 2 was used. Except for blending at the ratio shown in Table 2, the same experiment as in Example 1 was performed to determine the number of strand breaks. The results are shown in Table 2. Also in this example, no strand break was observed, and it was found that strands could be stably obtained (number of strand breaks: 0).

Example 8

As a high-dielectric material filler, a filler made of titanium oxide (T i 0 ₂ ) (SR-1 manufactured by Kayaku Co., Ltd., average particle size 0.26 jum) was used, and L CP 1 obtained in Synthesis Example 2 Except for blending in the proportions shown in Table 2, the same experiment as in Example 1 was performed to determine the number of times the land was cut. The results are shown in Table 2. Also in this example, no strand break was observed, and it was found that a strand could be stably obtained (number of strand breaks: 0).

Table 2

Examples 9 to 1 1 As a high dielectric material filler, a fibrous filler made of titanium oxide (T i 0 ₂ )

(Ishihara Sangyo Co., Ltd. Taipek P FR404, number average fiber length 2 to 4 jum, number average fiber diameter 0.3 to 0.5 im), and LCP 1 obtained in Synthesis Example 2 Except for blending at the ratio shown in 3, the same experiment as in Example 1 was performed to determine the number of strand breaks. The results are shown in Table 3. Also in this example, no strand breakage was observed, and it was found that strands were stably obtained (number of strand breaks: 0).

Example 1 2

Fibrous filler made of titanium oxide (T i 0 ₂ ) as a high-dielectric material filler (Ishihara Sangyo Co., Ltd. Typek P FR404, number average fiber length 2 to 4 / m, number average fiber diameter 0. 3 ~ .0.5 jum) and glass fiber (CS03 J APX-1 manufactured by Asahi Fiber Glass Co., Ltd.), except for LCP 1 obtained in Synthesis Example 2 and the ratio shown in Table 3 The same experiment as in Example 1 was performed to determine the number of strand breaks. The results are shown in Table 3. Also in this example, a slight strand breakage (strand breakage number: 2) was recognized, but there was no problem in practical use. Table 3

Comparative Example 1

 Using Prebolimer 1 obtained in Synthesis Example 1 and the same high dielectric material filler used in Example 1, Prebomer 1 is blended to 73% by volume and Filler to 27% by volume ( A total of 4. O kg) and a twin screw extruder (Ikegai Iron Works Co., Ltd. “PCM-30”) tried to pelletize by the strand method with a melting temperature of 295 ° C. could not. In addition, although various attempts were made to change the granulation temperature to determine whether the strands could be drawn, it was not possible to obtain a wristland only by changing the granulation temperature.

Comparative Example 2

 LCP 3 obtained in Synthesis Example 4 and the same high dielectric material filler used in Example 1 were blended so that 1_03 was 73 vol% and filler was 27 vol% (mixed powder total 4. O kg), a twin-screw extruder (Ikegai Iron Works Co., Ltd. “PCM- 30J”) tried to pelletize with a strand method with a melting temperature of 340 ° C, but was unable to draw the land. In addition, attempts were made to determine whether the strands could be drawn by changing the granulation temperature, but it was not possible to obtain a list by simply changing the granulation temperature.

Comparative Example 3

LCP4 obtained in Synthesis Example 5 and the same high dielectric material filler used in Example 1 were blended so as to have the ratio (capacity ratio) shown in Table 3 (total mixed powder 4.0 kg) ), Granulated by the wristland method at a granulation temperature of 340 ° C with a twin screw extruder (Ikegai Iron Works Co., Ltd. Γρ〇Μ-30) and confirmed that pellets (resin composition) were obtained. did. So from after the mixed powder was used 0. 5 kg, strand breakage number of was counted the number of scan Bok land cutting granulating a mixed powder 3. 0 k _g is 22 times, stably scan Bok Land Could not get. Comparative Example 4

The same experiment as in Comparative Example 3 was performed, except that LCP 5 obtained in Synthesis Example 6 and the same high dielectric material filler used in Example 1 were blended in the proportions shown in Table 3. The number of times the Sland runs out is 29 times, and the Sland cannot be obtained stably. Comparative Example 5

 LCP 6 obtained in Synthesis Example 7 and the same high dielectric material filler as used in Example 1 were blended in the proportions shown in Table 3 (mixed powder total 4. O kg), twin screw extruder (Ikegai Iron Works Co., Ltd. “PCM-30”) tried to granulate by restructuring at a granulation temperature of 345 ° C. When the count of the number of land cuts was counted from the point when 0.5 kg of mixed powder was used to the point when 3.0 kg of mixed powder was used, the number of land cuts was 24 times. No strands can be obtained and Comparative Example 6

 LCP 5 obtained in Synthesis Example 6 and the same high dielectric material filler used in Example 5 were blended in the proportions shown in Table 3 (mixed powder total 4. O kg), twin screw extruder (Ikegai Iron Works Co., Ltd., rpCM-30J) was granulated by the restrand method at a granulation temperature of 340 ° C, causing many strand breaks (strand breaks: 40 times or more). The number of strand breaks was counted up to 40 times, and no more counting was performed.

Comparative Example 7

LCP 5 obtained in Synthesis Example 6 and the same high-dielectric material filler used in Example 6 were blended in the proportions shown in Table 3 (mixed powder total 4. O kg), twin screw extruder (Ikegai Iron Works Co., Ltd. “PCM-30”) was granulated by the restructuring method at a granulation temperature of 340 ° C, resulting in frequent strand breaks (strand breaks: 40 times or more). The number of strand breaks was counted up to 40 times, and no more counting was performed.

Table 4

Example 1 3 ~ "! 7

 The composition pellets obtained in Examples 1 to 3 and Examples 5 to 8 were dried at 120 ° C. for 3 hours, and then injected into an injection molding machine (Nisshin Resin Industry Co., Ltd. 540-5 5 £. JIS K71 1 31 (1) dumbbell (thickness 1.2 mm) sample was molded at a cylinder temperature of 350 ° C and a mold temperature of 1300 ° C. The obtained sample was immersed for 60 seconds in ^ 160 solder (60% tin, 40% lead) at 2600 °. After that, the sample was pulled up and checked for foaming and swelling. The results are shown in Table 5. In addition, the composition pellets obtained in Examples 1 to 3 and Examples 5 to 8 were dried at 120 ° C. for 3 hours, and then injected with an injection molding machine (PS40E5ASE type manufactured by Kashiwa Plastic Industry Co., Ltd.). Molded at a cylinder temperature of 350 ° C and a mold temperature of 1 30 ° C. A test piece with a length of 1 27mm, a width of 12.7mm, and a thickness of 6.4mm (a sample for bending strength measurement) Produced. Then, the bending strength of these samples was measured by a method based on AS TMD 790. The results are shown in Table 5.

Furthermore, the composition pellets obtained in Examples 1 to 3 and Examples 5 to 8 were dried at 120 ° C. for 3 hours, and then injection molding machine (PS40E5A SE manufactured by Nissin Plastic Industry Co., Ltd.) Mold) at a cylinder temperature of 350 ° C and a mold temperature of 1 30 ° C. A test piece (dielectric property measurement sample) having a thickness of 64 mm, a width of 64 mm, and a thickness of 1 mm was produced. The dielectric properties (dielectric constant, dielectric loss tangent) of these samples at 1 GHz (measurement temperature 23 ° C) were evaluated using an HP impedance analyzer. The results are shown in Table 5.

Comparative Example 8

 As described above, in Comparative Example 4, strand breakage occurred and a composition pellet could not be stably obtained, but a pellet having a length of about 2 to 3 mm was selected, and Example 1 was selected. In the same experiment as 3 to 19, the presence or absence of foaming by solder, bending strength and dielectric properties were measured. The results are shown in Table 6.

Comparative Example 9

 In Comparative Example 6, the strands could not be stably drawn. Therefore, the composition extruded from the twin screw extruder was pulverized with a pulverizer to obtain a particulate composition of about 3 mm, and this particulate composition was used. This was the pellet of Comparative Example 6. In the same experiment as in Examples 13 to 19, the presence or absence of foaming by solder, bending strength, and dielectric properties were measured. The results are shown in Table 6.

Comparative Example 1 0

In Comparative Example 7, the strand could not be stably drawn. Therefore, the composition extruded from the twin-screw extruder was pulverized with a pulverizer to obtain a particulate composition of about 3 mm. Using this particulate composition, This was designated as Perezka of Comparative Example 7. In the same experiment as in Examples 13 to 19, the presence or absence of foaming by solder, bending strength, and dielectric properties were measured. The results are shown in Table 6.

Table 5

Table 6

Example 2 0-2 3

 The same experiment as in Example 13 was performed, except that the composition pellets obtained in Example 1 were replaced with the composition pellets obtained in Examples 9 to 12. Solder foam tests, flexural strength and dielectric properties (dielectric constant, dielectric loss tangent) were determined for the compacts. The results are shown in Table 7.

Table 7

Examples 24-28

 The composition pellets obtained in Examples 5 to 9 were dried at 120 ° C. for 3 hours, and then subjected to a cylinder temperature of 350 ° C. using a injection molding machine (PS40E5ASE manufactured by Nissin Plastic Industry Co., Ltd.). After molding at a mold temperature of 1300C, a molded product with a length of 127mm, a width of 12.7mm, and a thickness of 6.4mm was prepared (a sample for measuring bending strength). This molded product was cut to a length of 64 mm, a width of 12.7 mm, and a thickness of 6.4 mm, and used as a test piece (impact strength measurement sample). The impact strength of these samples (without notches) was measured according to the test method of AS TMD 256. The results are shown in Table 8.

Comparative Example 1 1 ~ "! 2

 The composition pellets obtained in Comparative Examples 6 to 7 were dried at 120 ° C for 3 hours, and then the cylinder temperature was 350 ° C using a injection molding machine (PS40 E5ASE type, manufactured by Nissin Plastic Industry Co., Ltd.). After molding at a mold temperature of 1300C, a molded product with a length of 1 27mm, a width of 12.7mm, and a thickness of 6.4mm was prepared (sample for measuring bending strength). This molded product is 64mm long and 1 width? 7 mm. Thickness was cut to 6.4 mm to obtain a test piece (impact strength measurement sample). And ASTMD256 test method

The impact strength of these samples was measured according to (no notch). The results are shown in Table 8.

Table 8

 Since the liquid crystal polyester resin compositions obtained in Examples 1 to 12 can stably obtain strands, stable composition pellets can be produced by the Strand method.

In addition, it was found that the pellet-like liquid crystal polyester resin compositions obtained in Examples 1 to 3 and Examples 5 to 12 were able to obtain molded bodies having extremely excellent solder foam tests, bending strength, and dielectric properties. . Furthermore, it was found that the pellet-like liquid crystal polyester resin compositions obtained in Examples 5 to 9 were able to obtain molded articles having extremely excellent impact strength.

 On the other hand, in the liquid crystal polyester resin composition obtained in Comparative Example 4, in addition to being difficult to stably obtain the composition pellets by the strand method, the obtained molded article was also inferior in bending strength and dielectric properties. . The liquid crystal polyester resin compositions of Comparative Examples 6 to 7 were completely incompatible with the strand method, and the obtained molded articles were inferior in bending strength and impact strength.

Claims

The scope of the claims

1. a divalent aromatic group represented by Αη, comprising a structural unit represented by the following formula (i), a structural unit represented by formula (ii), and a structural unit represented by formula (iii) , when the total of the divalent aromatic group represented by divalent aromatic groups and Ar ₃ which is represented by Ar ₂ and 100 molar%, 2, containing a 6-naphthalene Jiiru groups 40 mol% or more The flow start temperature is 280 ° C or higher,

Liquid crystal polyester (A) having a melt tension of 1 g or more measured at a temperature higher than the flow start temperature (A) 50 to 80% by volume,

Filler made of high dielectric material (B) 20-50% by volume,

A liquid crystal polyester resin composition comprising:

 O

 —— 0—— Αι ^ —— c — (i)

O 0

C——Ar ₂ 1 C ~-(ii)

O—— Ar ₃ — o (iii)

In the formula, η represents a divalent aromatic group selected from the group consisting of 2,6-naphthalene diyl group, 1,4-phenylene group and 4,4′-biphenylene group. Ar ₂ and Ar ₃ are each independently selected from the group consisting of 2,6-naphthalenedyl group, 1,4-phenylene group, 1.3-phenylene group and 4,4′-biphenylene group. Represents a divalent aromatic group. In addition, in the aromatic group represented by Αη, Ar ₂ or Ar ₃ , a part of the hydrogen atoms bonded to the aromatic ring is a halogen atom, an alkyl group having 1 to 10 carbon atoms, or a carbon atom having 6 to 20 carbon atoms. The aryl group may be substituted.

2. The liquid crystal polyester resin composition according to claim 1, wherein the filler (B) made of the high dielectric material is a filler containing titanium-based ceramics.

3. The titanium-based ceramics are T i 0 ₂ , Ba T i 0 ₃ , S r T i 0 ₃ , C a T i 0 ₃ , Mg T i 0 ₃ , B a S r T i ₂ 0 ₆ , _{B a N d 2 T i 4} 0 12, B a N d 2 T i 5 0 14 and Ba B i mainly containing ceramic selected from _{2 N d 2 T i 0 9} , the liquid crystal polyester resin composition according to claim 2, wherein object.

 4. a step of thermally melting the liquid crystal polyester (A) and the filler (B) made of a high dielectric material to obtain a melt;

Extruding the melt into a string to obtain a string composition;

Cutting the string composition and pelletizing;

The liquid crystal polyester resin composition according to any one of claims 1 to 3, which is obtained by a production method comprising:

 5. A molded article comprising the liquid crystal polyester resin composition according to any one of claims 1 to 4.

 6. The molded article according to claim 5, wherein the bending strength measured according to the test method of ASTM D790 is 1 OOM Pa or more.

 7. The molded product according to claim 5 or 6, wherein the impact strength measured according to the test method of ASTM D 256 is 10 OJZm or more.

 8. The molded product according to any one of claims 5 to 7, having a relative dielectric constant of 6.0 or more at a measurement temperature of 23 ° C and a frequency of 1 GHz.

 9. An antenna having the molded body according to any one of claims 5 to 8 and an electrode.