JP2016183308A - Liquid crystalline polyester resin composition and molded article of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystalline polyester resin composition that suppresses development of blisters when a molded article of the composition is heat treated and that has excellent stability in continuous molding and low water absorption, and a molded article made of the above composition.SOLUTION: The liquid crystalline resin composition is obtained by blending 10 to 100 parts by weight of a filler (B) and 0.05 to 5 parts by weight of a novolac epoxy compound (C) in 100 parts by weight of a liquid crystalline polyester (A) comprising a 4-hydroxybenzoic acid unit, 4,4'-dihydroxy biphenyl unit, hydroquinone unit, terephthalic acid unit and isophthalic acid unit.SELECTED DRAWING: None

Description

  The present invention relates to a liquid crystalline polyester resin composition and a molded article using the same.

  Liquid crystalline polyester is excellent in heat resistance, fluidity and dimensional stability. For this reason, the demand is expanding mainly for electric / electronic component applications that require these characteristics. For these applications, studies are being made to improve various properties by blending an epoxy compound with a liquid crystalline polyester. For example, by blending a liquid crystalline polyester resin composition comprising liquid crystalline polyester and acicular titanium oxide with a bisphenol A type epoxy compound having a specific epoxy equivalent, fluidity and interfacial adhesion are improved, and high elastic modulus. In addition, a proposal has been made for a liquid crystalline polyester resin composition (see, for example, Patent Document 1) that provides tracking resistance against tracking and the like. In addition, a liquid crystalline polyester resin composition having excellent mechanical strength, comprising an epoxy compound having two or more glycidyl ester groups as a compatibilizing agent in a liquid crystalline polyester resin composition using a combination of a liquid crystalline polyester and another thermoplastic resin. Proposals of products (for example, see Patent Document 2) have been made. In addition, liquid crystalline polyester for sealing electrical components in which liquid crystalline polyester resin composition composed of liquid crystalline polyester and inorganic powder is blended with an epoxy compound having a specific molecular weight and epoxy equivalent to suppress deterioration due to heat or hydrolysis. There has been proposed a resin composition (for example, see Patent Document 3). In addition, a novolac epoxy compound is blended with a thermoplastic polyester resin composition comprising two or more kinds of resins containing thermoplastic polyester and a flame retardant to promote the uneven distribution of the resin species in the molded product, and flame retardancy There has been proposed a thermoplastic polyester resin composition (see, for example, Patent Document 4) with improved properties.

JP 2012-31391 A JP-A-5-86267 Japanese Patent Laid-Open No. 62-135516 JP 2014-88515 A

  However, in such prior art, due to the low heat resistance of the epoxy compound and the large amount of the epoxy compound, the epoxy compound is thermally deteriorated during the processing of the liquid crystalline polyester resin composition, and the resulting molded product is heat treated. Sometimes the surface of the molded product is deformed and blistering occurs, or the amount of cushion that is the amount of resin left at the tip of the molding machine cylinder for maintaining the pressure of the molded product during continuous molding is unstable, resulting in variations in the characteristics of the molded product. There was a problem that occurred. In addition, when a molded product of a liquid crystalline polyester resin composition is used for electrical / electronic parts, the epoxy compound is thermally deteriorated during reflow treatment of the resulting molded product, and the surface of the molded product is deformed and blistering occurs. The liquid crystalline polyester resin composition has a problem that the electrical system malfunctions due to water absorption. Therefore, the conventional liquid crystalline polyester resin composition suppresses blisters during heat treatment of molded products, continuous molding stability, and further suppresses blisters during heat treatment of molded products required for use in electrical and electronic component applications, The problem of achieving low water absorption at the same time is not fully satisfactory, and further improvements are required.

  The present invention relates to a liquid crystalline polyester resin composition excellent in heat resistance for suppressing blisters during heat treatment of molded products, continuous molding stability for suppressing variation in cushion amount during continuous molding, and low water absorption, and It is an object to provide a used molded product.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a liquid crystalline polyester resin composition containing a filler and an epoxy compound having a specific structure in a liquid crystalline polyester having a specific structural unit is more specific. In addition, it has been found that a molded product suitable for use in electrical and electronic parts can be obtained by suppressing the occurrence of blistering at the time of heat treatment of the molded product, excellent in continuous molding stability and low water absorption of the molded product. The invention has been reached.

That is, the present invention has been made to solve the above-described problems, and embodiments of the present invention can include at least a part of the following configurations.
(1) 10 to 100 parts by weight of filler (B) with respect to 100 parts by weight of liquid crystalline polyester (A) comprising the following structural units (I), (II), (III), (IV) and (V) A liquid crystalline polyester resin composition comprising 0.05 to 5 parts by weight of a novolac type epoxy compound (C).

(2) The liquid crystalline polyester resin composition as described in (1), wherein the novolac type epoxy compound (C) has an epoxy equivalent of 100 to 500 g / equivalent.
(3) The liquid crystalline polyester resin composition according to (1) or (2), wherein the novolac type epoxy compound (C) has a structure represented by the following general formula (VI).

(In the general formula (VI), X represents a divalent group represented by the general formula (VII) or (VIII). In the general formulas (VI) to (VII), R ^{1 to} R ⁴ are Each independently represents an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 10 carbon atoms, and may be the same or different, and R ⁵ is hydrogen, an alkyl group having 1 to 8 carbon atoms or 6 to 6 carbon atoms; In formula (VI), n is a natural number of 1 to 10. In formulas (VI) to (VII), a, c, and d are each independently 0 to 4. Represents an integer, and b represents an integer of 0 to 3.)
(4) A molded product obtained by molding the liquid crystalline polyester resin composition according to any one of (1) to (3).

  With the liquid crystalline polyester resin composition of the present invention, the occurrence of blistering during the heat treatment of the molded product can be suppressed, and a molded product having excellent continuous molding stability and excellent low water absorption can be obtained. These molded articles are particularly suitable for electrical / electronic component applications such as connectors and relays.

  Hereinafter, the present invention will be described in detail.

[Liquid crystal polyester]
The liquid crystalline polyester (A) used in the present invention is a polyester called a thermotropic liquid crystal polymer that exhibits optical anisotropy when melted, and has the following structural units (I), (II), (III), (IV ) And (V).

  The raw material monomer constituting the structural unit (I) is not particularly limited as long as it is a structure capable of forming the structural unit (I), but p-hydroxybenzoic acid, an acylated product of its hydroxyl group, an esterified product of a carboxyl group, an acid Examples thereof include carboxylic acid derivatives such as halides and acid anhydrides, and p-hydroxybenzoic acid is preferable. The raw material monomer constituting the structural unit (II) is not particularly limited as long as it is a structure that can form the structural unit (II), and examples thereof include 4,4′-dihydroxybiphenyl and acylated products of the hydroxyl groups thereof. 4'-dihydroxybiphenyl is preferred. Although the raw material monomer which comprises structural unit (III) will not be specifically limited if it is a structure which can form structural unit (III), Hydroquinone, its acylated thing, etc. are mentioned, Hydroquinone is preferable. The raw material monomer constituting the structural unit (IV) is not particularly limited as long as it is a structure capable of forming the structural unit (IV), but carboxylic acid such as terephthalic acid or an esterified product of its carboxyl group, an acid halide, an acid anhydride, etc. Acid derivatives and the like, and terephthalic acid is preferable. The raw material monomer constituting the structural unit (V) is not particularly limited as long as it is a structure capable of forming the structural unit (V), but is not limited to isophthalic acid or an esterified product of its carboxyl group, an acid halide, an acid anhydride or the like. Acid derivatives and the like, and isophthalic acid is preferred.

  When the liquid crystalline polyester (A) used in the present invention is composed of the above structural units, the obtained liquid crystalline polyester resin composition is excellent in heat resistance and the amount of gas generation is suppressed. Therefore, a molded article using the liquid crystalline polyester resin composition suppresses the occurrence of blistering during heat treatment of the molded article, and is excellent in continuous molding stability and low water absorption.

  When the liquid crystalline polyester (A) does not have the above structural unit, the heat resistance becomes low, so blistering occurs during the heat treatment of the molded product, the continuous molding stability is deteriorated, and the low water absorption is also deteriorated. To do. Alternatively, the molding temperature of the liquid crystalline polyester resin composition increases due to an increase in the melting point of the liquid crystalline polyester, so that the end groups of the liquid crystalline polyester and the novolac type epoxy compound are thermally deteriorated during the molding process, and the molded product is heat treated. Occasionally blisters occur, the stability of continuous molding deteriorates, and the low water absorption also deteriorates.

  The content of the structural unit (I) in the liquid crystalline polyester (A) of the present invention is preferably 65 mol% or more, and 68 mol based on the total content of the structural units (I), (II) and (III). % Or more is more preferable. On the other hand, the content of the structural unit (I) is preferably 80 mol% or less, and more preferably 78 mol% or less with respect to the total content of the structural units (I), (II) and (III).

  Moreover, 55 mol% or more is preferable with respect to the sum total of content of structural unit (II) and (III), and, as for content of structural unit (II), 58 mol% or more is more preferable. On the other hand, the content of the structural unit (II) is preferably 85 mol% or less, more preferably 78 mol% or less, and even more preferably 73 mol% or less with respect to the total content of the structural units (II) and (III). preferable.

  Further, the content of the structural unit (IV) is preferably 50 mol% or more, more preferably 55 mol% or more, and further preferably 60 mol% or more with respect to the total content of the structural units (IV) and (V). preferable. On the other hand, the content of the structural unit (IV) is preferably 95 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less with respect to the total content of the structural units (IV) and (V). preferable.

  By making content of the said structural unit (I)-(V) into the said range, since liquid crystalline polyester excellent in heat resistance, a mechanical characteristic, and low gas property is obtained easily, it is preferable. In addition, a liquid crystalline polyester resin composition using the same is preferable because it can suppress the occurrence of blistering during heat treatment of the molded product and suppress variation in the cushion amount during continuous molding.

  Further, the total of the structural units (II) and (III) and the total of the structural units (IV) and (V) are substantially equimolar. Here, “substantially equimolar” means that the structural unit constituting the polymer main chain excluding the terminal is equimolar. For this reason, the aspect which does not necessarily become equimolar when it includes even the structural unit which comprises the terminal can satisfy the requirement of “substantially equimolar”.

About the liquid crystalline polyester (A) of this invention, the calculation method of content of each structural unit is shown below. First, the liquid crystalline polyester is weighed into an NMR (nuclear magnetic resonance) test tube and dissolved in a solvent in which the liquid crystalline polyester is soluble (for example, a pentafluorophenol / heavy tetrachloroethane-d ₂ mixed solvent). Next, about a solution, < ¹ > H-NMR spectrum measurement is performed and it can calculate from the peak area ratio derived from each structural unit.

  The melting point (Tm) of the liquid crystalline polyester (A) of the present invention is preferably 220 ° C. or higher, more preferably 270 ° C. or higher, and further preferably 300 ° C. or higher from the viewpoint of heat resistance. On the other hand, from the viewpoint of workability, the melting point (Tm) of the liquid crystalline polyester is preferably 350 ° C. or less, more preferably 345 ° C. or less, and further preferably 340 ° C. or less.

The melting point (Tm) is measured by differential scanning calorimetry. Specifically, first, an endothermic peak temperature (Tm ₁ ) is observed by heating the polymer that has been polymerized from room temperature to a temperature rising condition of 20 ° C./min. After observation of an endothermic peak temperature (Tm _1), holding the polymer for 5 minutes at a temperature of the endothermic peak temperature _(Tm 1) + 20 ℃. Thereafter, the polymer is cooled to room temperature under a temperature drop condition of 20 ° C / min. And an endothermic peak temperature is observed by heating a polymer on temperature rising conditions of 20 degree-C / min. The melting point (Tm) refers to the endothermic peak temperature.

  The number average molecular weight of the liquid crystalline polyester (A) used in the present invention is preferably 3,000 or more and more preferably 8,000 or more from the viewpoint of mechanical strength. On the other hand, from the viewpoint of fluidity, the number average molecular weight of the liquid crystalline polyester is preferably 50,000 or less, more preferably 30,000 or less, and even more preferably 20,000 or less.

  The number average molecular weight can be measured by GPC (gel permeation chromatograph) / LALLS method. In this method, a solvent in which the liquid crystalline polyester is soluble is used as an eluent. Examples of the solvent in which the liquid crystalline polyester is soluble include halogenated phenols and a mixed solvent of a halogenated phenol and a general organic solvent. Preferable are pentafluorophenol and a mixed solvent of pentafluorophenol and chloroform. Among them, a pentafluorophenol / chloroform mixed solvent is preferable from the viewpoint of handleability.

  The GPC measurement uses, for example, a Waters GPC device, a Waters differential refractive index detector RI2410, and Showa Denko's columns Shodex K-806M (two) and K-802 (one). And do it. As an eluent, pentafluorophenol / chloroform (35/65 w / w%) is used. GPC measurement can be performed under the conditions of a measurement temperature of 23 ° C., a flow rate of 0.8 mL / min, and a sample injection amount of 200 μL (concentration: 0.1%). The LALLS measurement can be performed, for example, using a low angle laser light scattering photometer KMX-6 manufactured by Chromatix, under the conditions of a detector wavelength of 633 nm (He—Ne) and a detector temperature of 23 ° C.

  The melt viscosity of the liquid crystalline polyester (A) used in the present invention is preferably 1 Pa · s or more, more preferably 5 Pa · s or more, and further preferably 15 Pa · s or more from the viewpoint of mechanical strength. On the other hand, from the viewpoint of fluidity, the melt viscosity of the liquid crystalline polyester is preferably 200 Pa · s or less, more preferably 100 Pa · s or less, and even more preferably 50 Pa · s or less.

  This melt viscosity is a value measured by a Koka flow tester at a temperature of the melting point (Tm) of the liquid crystalline polyester + 20 ° C. and a shear rate of 1000 / sec.

  The method for producing the liquid crystalline polyester (A) used in the present invention is not particularly limited, and can be produced according to a known polyester polycondensation method. As a known polyester polycondensation method, for example, p-hydroxybenzoic acid, 4,4′-dihydroxybiphenyl and hydroquinone are reacted with terephthalic acid and isophthalic acid with acetic anhydride to acetylate the phenolic hydroxyl group, and then removed. The method of manufacturing liquid crystalline polyester by acetic acid polycondensation is mentioned.

  The method for producing a liquid crystalline polyester by the above production method is preferably used because it is industrially excellent in controlling the terminal structure of the liquid crystalline polyester and controlling the degree of polymerization.

  Hereinafter, the production method of the liquid crystalline polyester (A) used in the present invention is p-hydroxybenzoic acid as the compound having the structural unit (I), and 4,4′-dihydroxybiphenyl as the compound having the structural unit (II). The case where hydroquinone is used as the compound having the structural unit (III), terephthalic acid is used as the compound having the structural unit (IV), and isophthalic acid is used as the compound having the structural unit (V) will be specifically described.

  In the said manufacturing method, the usage-amount of acetic anhydride is more than 1.00 molar equivalent of the sum total of the phenolic hydroxyl group of p-hydroxybenzoic acid, 4,4'- dihydroxybiphenyl, and hydroquinone from a viewpoint of advancing a polymerization reaction rapidly. Preferably, it is 1.03 molar equivalent or more, and more preferably 1.05 molar equivalent or more. On the other hand, from the viewpoint of controlling the terminal structure of the liquid crystalline polyester, the amount of acetic anhydride used is preferably 1.15 molar equivalents or less of the total of the phenolic hydroxyl groups of p-hydroxybenzoic acid, 4,4′-dihydroxybiphenyl and hydroquinone. 1.12 molar equivalents or less is more preferable. Furthermore, by making the usage-amount of acetic anhydride into the said range, the acetylation rate of hydroquinone with a small acetylation reaction rate can be controlled, and the terminal structure of liquid crystalline polyester can be controlled easily. Thereby, a liquid crystalline polyester with less gas generation can be obtained, the occurrence of blistering during heat treatment of the molded product is suppressed, and a liquid crystalline polyester resin composition excellent in continuous molding stability and low water absorption is obtained. be able to.

  The method for producing the liquid crystalline polyester (A) by a deacetic acid polycondensation reaction includes a melt polymerization method in which the polycondensation reaction is completed by reacting under reduced pressure at a temperature at which the liquid crystalline polyester melts. The melt polymerization method is an advantageous method for producing a uniform polymer, and a liquid crystalline polyester with less gas generation can be obtained, which is preferable.

  Examples of the method for producing the liquid crystalline polyester (A) by a deacetic acid polycondensation reaction include the following methods. A predetermined amount of p-hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, hydroquinone, terephthalic acid, isophthalic acid and acetic anhydride are charged into a reaction vessel and heated with stirring in a nitrogen gas atmosphere to acetylate the hydroxyl group. Let The reaction vessel includes a stirring blade and a distillation pipe, and a discharge port in the lower part. Thereafter, the mixture is heated up to the melting temperature of the liquid crystalline polyester and then subjected to polycondensation by reducing the pressure to complete the reaction.

  The temperature for acetylation is preferably 130 ° C. or higher, more preferably 135 ° C. or higher, from the viewpoint of promoting the reaction. On the other hand, from the viewpoint of suppressing the excessive progress of the reaction, the temperature for acetylation is preferably 300 ° C. or lower, more preferably 200 ° C. or lower. The acetylation reaction time is preferably 1 hour or longer from the viewpoint of increasing the reaction rate. On the other hand, from the viewpoint of productivity, the acetylation reaction time is preferably 6 hours or less, and more preferably 4 hours or less. The acetylation reaction may be carried out under normal pressure or under pressure.

  The polycondensation temperature is a melting temperature of the liquid crystalline polyester, for example, in the range of 250 to 370 ° C., and preferably a melting point of the liquid crystalline polyester + 10 ° C. or higher.

  The pressure for polycondensation is preferably 0.1 mmHg (13.3 Pa) or more from the viewpoint of productivity. On the other hand, from the viewpoint of promoting the polycondensation reaction, the pressure during polycondensation is preferably 20 mmHg (2660 Pa) or less, more preferably 10 mmHg (1330 Pa) or less, and even more preferably 5 mmHg (665 Pa) or less.

  In addition, acetylation and polycondensation may be performed continuously in the same reaction vessel, or acetylation and polycondensation may be performed in different reaction vessels.

  Specific examples of the method for removing the obtained polymer from the reaction vessel after the completion of the polymerization include the following methods. In this method, the inside of the reaction vessel is pressurized at a temperature at which the polymer melts, the polymer is discharged from a discharge port provided in the reaction vessel, and the discharged polymer is cooled in cooling water. The pressurization in the said reaction container can be 0.02-0.5 MPa, for example. The discharge port may be provided at the lower part of the reaction vessel. The polymer may be discharged in a strand form from the discharge port. Resin pellets can be obtained by cutting the polymer cooled in the cooling liquid into pellets.

  As a method for producing the liquid crystalline polyester (A) used in the present invention, the polycondensation reaction can be completed by a solid phase polymerization method. Examples of the treatment by the solid phase polymerization method include the following methods. First, the polymer or oligomer of liquid crystalline polyester (A) is pulverized by a pulverizer. The pulverized polymer or oligomer is heated under a nitrogen stream or under reduced pressure, and polycondensed to a desired degree of polymerization to complete the reaction. The said heating can be performed for 1 to 50 hours in the range of melting | fusing point-50 degreeC-melting point-5 degreeC (for example, 200-300 degreeC) of liquid crystalline polyester.

  The polycondensation reaction of the liquid crystalline polyester (A) proceeds even without catalyst, but metal compounds such as stannous acetate, tetrabutyl titanate, potassium acetate and sodium acetate, antimony trioxide, and magnesium metal are used as catalysts. You can also.

[Filler]
The liquid crystalline polyester resin composition of the present invention is characterized by blending a filler (B). Although the filler (B) used by this invention is not specifically limited, For example, fillers, such as a fiber form, a whisker form, plate shape, a powder form, a granular form, can be mentioned. Specifically, as fibrous and whisker-like fillers, glass fibers, PAN-based and pitch-based carbon fibers, stainless steel fibers, metal fibers such as aluminum fibers and brass fibers, aromatic polyamide fibers and liquid crystalline polyester fibers, etc. Organic fiber, gypsum fiber, ceramic fiber, asbestos fiber, zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride Examples include whiskers and acicular titanium oxide. Examples of the plate-like filler include mica, talc, kaolin, glass flake, clay, molybdenum disulfide, and wollastonite. Examples of powdery and granular fillers include silica, glass beads, titanium oxide, zinc oxide, calcium polyphosphate, and graphite. The surface of the filler used in the present invention may be treated with a known coupling agent (for example, a silane coupling agent or a titanate coupling agent) or other surface treatment agent. Moreover, you may use 2 or more types together for said filler used for this invention.

  Among these fillers, glass fiber is particularly preferable from the viewpoint of mechanical strength and heat resistance. The type of glass fiber is not particularly limited as long as it is generally used for reinforcing resin, and can be selected from, for example, long fiber type or short fiber type chopped strands and milled fibers.

  The glass fiber used in the present invention is preferably weakly alkaline in terms of mechanical strength. In particular, glass fibers having a silicon oxide content of 50 to 80% by weight are preferably used, and more preferably glass fibers having a silicon oxide content of 65 to 77% by weight. The glass fiber is preferably treated with an epoxy-based, urethane-based, acrylic-based coating or sizing agent, and epoxy-based is particularly preferable.

  The glass fiber is preferably treated with a coupling agent such as a silane or titanate or other surface treatment agent, and an epoxysilane or aminosilane coupling agent is particularly preferable. The glass fiber may be coated or bundled with a thermoplastic resin such as ethylene / vinyl acetate copolymer or a thermosetting resin such as epoxy resin.

  The amount of the filler (B) is 10 to 100 parts by weight with respect to 100 parts by weight of the liquid crystalline polyester (A). By setting the blending amount of the filler to 10 parts by weight or more, heat resistance and mechanical strength can be further improved, occurrence of blistering during heat treatment of the molded product is suppressed, and low water absorption is excellent. The blending amount of the filler is preferably 15 parts by weight or more, and more preferably 20 parts by weight or more. Moreover, by making the compounding quantity of a filler into 100 weight part or less, fluidity | liquidity and a softness | flexibility can be improved, the dispersion | variation in the amount of cushions at the time of continuous molding can be suppressed, and continuous molding stability improves. . The amount of the filler is preferably 80 parts by weight or less, and more preferably 60 parts by weight or less.

  When the blending amount of the filler (B) is less than 10 parts by weight with respect to 100 parts by weight of the liquid crystalline polyester (A), or when no filler is blended, the heat resistance of the liquid crystalline polyester resin composition, the machine The strength is not sufficient, and blistering during heat treatment of the molded product increases. Moreover, the amount of water absorption increases. On the other hand, when the blending amount of the filler exceeds 100 parts by weight with respect to 100 parts by weight of the liquid crystalline polyester (A), the fluidity and flexibility of the liquid crystalline polyester resin composition are lowered, and the cushion amount varies during continuous molding. Increases and the stability of continuous molding decreases.

[Novolac type epoxy compound]
The liquid crystalline polyester resin composition of the present invention is characterized by blending a novolac type epoxy compound (C). The novolac type epoxy compound (C) blocks the end group of the liquid crystalline polyester, thereby suppressing the generation of decomposition gas due to the thermal deterioration of the end group of the liquid crystalline polyester, and the occurrence of blistering during the heat treatment of the molded product. In addition, the stability of continuous molding is improved. Furthermore, since the novolac type epoxy compound (C) blocks the terminal group of the liquid crystalline polyester, the liquid crystalline polyester is prevented from deteriorating from the terminal group due to water absorption, and is excellent in low water absorption.

  The above effect is presumed to be because the novolak-type epoxy compound is excellent in heat resistance and the structure of the compound is excellent in reactivity with the liquid crystalline polyester.

  The novolak type epoxy compound (C) is an epoxy compound having a structure in which an epoxy group is added to a novolak resin obtained using phenol or cresol as a starting material. For example, a phenol novolac type epoxy compound, a cresol novolak type epoxy compound, a novolak type epoxy compound having a dicyclopentadiene skeleton, a novolak type epoxy compound having a biphenyl skeleton, a novolak type epoxy compound having a naphthol skeleton, a triphenylmethane skeleton Examples include novolak type epoxy compounds.

  When the structure of the epoxy compound (C) used in the present invention is not a novolak type epoxy, the resulting resin composition increases the occurrence of blistering during heat treatment of the molded product, and the cushion amount variation during continuous molding is increased. The water absorption increases. This is presumably because the heat resistance of the epoxy compound is insufficient and the reactivity with the liquid crystalline polyester is poor.

  The novolac type epoxy compound (C) used in the present invention may be used in combination of two or more.

  The amount of the novolac epoxy compound (C) used in the present invention is 0.05 to 5 parts by weight with respect to 100 parts by weight of the liquid crystalline polyester (A). By adding 0.05 parts by weight or more of the novolac-type epoxy compound, it is possible to improve the blocking rate of the terminal group of the liquid crystalline polyester, suppress the occurrence of blistering during heat treatment of the molded product, and continuous molding Excellent stability and low water absorption. The amount of the novolac type epoxy compound is preferably 0.1 parts by weight or more, and more preferably 0.3 parts by weight or more. On the other hand, when the amount of the novolak type epoxy compound is 5 parts by weight or less, the amount of the terminal group of the liquid crystalline polyester and the amount of the unreacted epoxy compound is suppressed, so that the epoxy compound is excessively present in the resin composition. It suppresses the occurrence of blistering during heat treatment of the molded product, and is excellent in continuous molding stability. The amount of the novolac type epoxy compound is preferably 4 parts by weight or less, and more preferably 3 parts by weight or less.

  When the compounding amount of the novolac type epoxy compound is less than 0.05 parts by weight or when the novolac type epoxy compound is not compounded, the terminal blocking effect of the liquid crystalline polyester is insufficient, and the liquid crystal polyester is derived from the terminal group. As the generated gas increases, blistering increases during heat treatment of the molded product, and the cushion amount during continuous molding varies. Moreover, the terminal group of liquid crystalline polyester is easy to decompose | disassemble and deteriorate at the time of water absorption, and the water absorption amount of a molded article increases. On the other hand, if the amount of the novolac type epoxy compound is more than 5 parts by weight, the novolac type epoxy compound that cannot react with the terminal group of the liquid crystalline polyester increases. The swelling during heat treatment increases, and the cushion amount during continuous molding varies. Further, the presence of an unreacted novolac type epoxy compound increases the water absorption of the molded product.

  The epoxy equivalent of the novolak type epoxy compound (C) used in the present invention is preferably in the range of 100 to 500 g / equivalent.

  In addition, the epoxy equivalent said here is the gram number (g / equivalent) of the epoxy compound containing 1 equivalent of epoxy groups. The epoxy equivalent can be calculated by the following method. 1 g of trifluoroacetic anhydride is added to 0.5 g of the epoxy compound, treated in an airtight stopper at 80 ° C. for 1 hour, then opened and further treated for 1 hour, diluted with 10 mL of tetrahydrofuran to prepare a sample solution. Using “HLC-8220 GPC” manufactured by Tosoh Corporation, columns “TSK-GEL G2000HXL”, “TSK-GEL 3000HXL”, “TSK-GEL 4000HXL” manufactured by Tosoh Corporation, and a detector RI (differential refractometer). The number average molecular weight is measured. The column temperature is 40 ° C., and tetrahydrofuran is used as a developing solvent. An epoxy equivalent is calculated from the obtained number average molecular weight and the number of epoxy groups in the epoxy compound.

  When the epoxy equivalent of the novolak type epoxy compound is 100 g / equivalent or more, the epoxy compound has excellent heat resistance, and the thermal degradation of the epoxy compound during production and processing of the liquid crystalline polyester resin composition is suppressed. Generation of blisters during heat treatment is suppressed, and continuous molding stability and low water absorption are excellent. On the other hand, when the epoxy equivalent of the novolak type epoxy compound is 500 g / equivalent or less, the amount of the epoxy compound necessary for blocking the terminal group of the liquid crystalline polyester can be reduced. Generation is suppressed, and continuous molding stability and low water absorption are excellent.

  The novolac epoxy compound (C) used in the present invention preferably has a structure represented by the following general formula (VI).

(In the general formula (VI), X represents a divalent group represented by the general formula (VII) or (VIII). In the general formulas (VI) to (VII), R ^{1 to} R ⁴ are Each independently represents an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 10 carbon atoms, and may be the same or different, and R ⁵ is hydrogen, an alkyl group having 1 to 8 carbon atoms or 6 to 6 carbon atoms; Represents an aryl group of 10. In the general formula (VI), n is a natural number of 1 to 10. In the general formulas (VI) to (VII), a, c and d are each independently 0 to 4; Represents an integer, and b represents an integer of 0 to 3.)

  When the novolac type epoxy compound (C) used in the present invention has a structure represented by the above general formula, the resulting liquid crystalline polyester resin composition has heat resistance, continuous molding stability, and low water absorption. Since it improves specifically, it is preferable. This is presumably because the reactivity between the epoxy compound and the liquid crystalline polyester is further improved.

  The novolak type epoxy compound (C) that can be used in the present invention is commercially available, and specific product names include XD-1000 (manufactured by Nippon Kayaku), NC-3000-H (manufactured by Nippon Kayaku). ) And the like.

  The liquid crystalline polyester resin composition of the present invention further includes an antioxidant, a heat stabilizer (for example, hindered phenol, hydroquinone, phosphites, and substituted products thereof), ultraviolet rays and the like within a range not impairing the effects of the present invention. Absorbers (eg, resorcinol, salicylate), anti-coloring agents such as phosphites, hypophosphites, lubricants and mold release agents (montanic acid and its metal salts, its esters, their half esters, stearyl alcohol, stearamide) And polyethylene wax), colorants containing dyes or pigments, carbon black, crystal nucleating agents, plasticizers, flame retardants (bromine flame retardants, phosphorus flame retardants, red phosphorus, silicone flame retardants) Etc.), a usual additive selected from a flame retardant aid and an antistatic agent can be blended. Alternatively, a polymer other than the liquid crystalline polyester can be blended to further impart predetermined characteristics.

  The method for blending the filler, epoxy compound, and other additives with the liquid crystalline polyester resin composition of the present invention is not particularly limited. For example, a dry blend method in which a solid filler, an epoxy compound, and other additives are blended with liquid crystalline polyester, or a liquid epoxy compound, other additives, and the like are blended with liquid crystalline polyester and filler. Solution blending method, method of adding filler, epoxy compound, and other additives during polymerization of liquid crystalline polyester, method of melt kneading liquid crystalline polyester and filler, epoxy compound, and other additives, etc. Among them, melt kneading is preferable. A known method can be used for melt kneading. For example, using a Banbury mixer, rubber roll machine, kneader, single-screw or twin-screw extruder, etc., it can be melt-kneaded at a melting point of the liquid crystalline polyester + 50 ° C. or lower to obtain a liquid crystalline polyester resin composition. Of these, a twin screw extruder is preferable.

  About a twin-screw extruder, in order to improve the dispersibility of liquid crystalline polyester and a filler, and to improve the reactivity of an epoxy compound, it is preferable to provide one or more kneading parts, and to provide two or more places. More preferably. For example, when the filler is added from the side feeder, the kneading portion is installed at one or more locations upstream of the side feeder of the filler in order to promote plasticization of the liquid crystalline polyester. In order to improve the dispersibility with the material, it is preferable to install two or more in total, one or more on the downstream side of the side feeder.

  Moreover, in order to remove the water | moisture content in a twin-screw extruder, and the decomposition product produced during kneading | mixing, it is preferable to provide the vent part and it is more preferable to provide two or more places. For example, when the filler is added from the side feeder, the vent portion is installed at one or more locations upstream from the side feeder into which the filler is introduced in order to remove moisture adhering to the liquid crystalline polyester. In order to remove the cracked gas component and the air brought in at the time of supplying the filler, it is preferable to install two or more places in total, one or more places downstream of the side feeder. The vent part may be under normal pressure or under reduced pressure.

  For the twin screw extruder, in order to suppress thermal deterioration of the epoxy compound and improve the reactivity with the terminal group of the liquid crystalline polyester, the most downstream vent part is provided adjacent to the downstream side of the kneading part, It is preferable to set the cylinder setting temperature of the kneading part smaller than the cylinder setting temperature of the vent part. By setting the cylinder setting temperature of the kneading part and the vent part within the above range, the reaction between the end group of the liquid crystalline polyester and the epoxy compound is promoted while suppressing the thermal deterioration of the epoxy compound due to the shear heat generation at the kneading part. This is preferable. Further, it is preferable because an unreacted epoxy compound or a thermally decomposed epoxy compound that causes an increase in gas generation amount can be removed at the vent portion without being taken into the liquid crystalline polyester resin composition.

  As the kneading method, 1) a method in which liquid crystalline polyester (A), filler (B), novolac type epoxy compound (C), and other additives are added all at once from the original feeder and kneaded (collective kneading method) ), 2) Liquid crystalline polyester (A), novolac epoxy compound (C), and other additives are added from the original feeder and kneaded, and then the filler (B) and other additives are added from the side feeder. And kneading (side feed method), 3) preparing a master pellet containing liquid crystalline polyester (A), epoxy compound (C), and other additives at a high concentration, and then mastering to a specified concentration Any method such as a method of kneading the pellet with the liquid crystalline polyester (A) and the filler (B) (master pellet method) may be used.

  The liquid crystalline polyester resin composition of the present invention has an excellent surface appearance (color tone) by performing known melt molding such as injection molding, injection compression molding, compression molding, extrusion molding, blow molding, press molding, and spinning. It can be processed into a molded product having mechanical properties, heat resistance and flame retardancy. Examples of the molded product include injection molded products, extrusion molded products, press molded products, sheets, pipes, unstretched films, uniaxially stretched films, various films such as biaxially stretched films, unstretched yarns, superstretched yarns, and the like. Examples include various fibers. In particular, injection molding is preferred from the viewpoint of processability.

  Molded articles made of the liquid crystalline polyester resin composition thus obtained include, for example, various gears, various cases, sensors, LED lamps, connectors, sockets, resistors, relay cases, relay bases, relay spools, switches, Coil bobbin, condenser, variable capacitor case, optical pickup, oscillator, various terminal boards, transformer, plug, printed wiring board, tuner, speaker, microphone, headphones, small motor, magnetic head base, power module, housing, semiconductor, liquid crystal display Parts, FDD carriages, FDD chassis, HDD parts, motor brush holders, parabolic antennas, thermal protectors, electrical and electronic parts such as computer-related parts; VTR parts, TV parts, Iro , Hair dryer, rice cooker parts, microwave oven parts, acoustic parts, audio equipment parts such as audio / laser discs (registered trademark) / compact discs, lighting parts, refrigerator parts, air conditioner parts, typewriter parts, word processor parts, etc. Household / office electrical product parts; office computer-related parts, telephone-related parts, facsimile-related parts, copier-related parts, cleaning jigs, oilless bearings, stern bearings, submersible bearings, motor parts, lighters , Machine-related parts typified by typewriters, optical equipment typified by microscopes, binoculars, cameras, watches, precision machine-related parts; alternator terminals, alternator connectors, IC regulators, light dimmer potentiometer bases, exhaust gas Various valves such as valves, various pipes related to fuel, exhaust system, intake system, air intake nozzle snorkel, intake manifold, fuel pump, engine coolant joint, carburetor main body, carburetor spacer, exhaust gas sensor, coolant sensor, oil temperature Sensor, throttle position sensor, crankshaft position sensor, air flow meter, brake butt wear sensor, thermostat base for air conditioner, motor insulator for air conditioner, automotive motor insulator such as power window, heating hot air flow control valve, brush for radiator motor Holder, water pump impeller, turbine vane, wiper motor related parts, distributor, starter Switch, starter relay, transmission wire harness, window washer nozzle, air conditioner panel switch board, coil for fuel solenoid valve, fuse connector, horn terminal, electrical component insulation plate, step motor rotor, lamp bezel, lamp socket, lamp reflector , Lamp housings, brake pistons, solenoid bobbins, engine oil filters, ignition device cases, and other automobile / vehicle-related parts.

  Among the various uses described above, the molded product of the present invention has excellent heat resistance, suppresses the occurrence of blistering during heat treatment, and is useful for small electrical and electronic components by taking advantage of continuous molding stability and low water absorption. For example, it is used for connectors and relay cases.

  Hereinafter, although an example explains the present invention still in detail, the gist of the present invention is not limited only to the following example.

  The liquid crystalline polyester (A) used in each example and comparative example is shown below.

  The composition analysis and characteristic evaluation of the liquid crystalline polyester were performed by the following methods.

(1) Composition Analysis of composition analysis liquid crystalline polyester of the liquid crystalline polyester ^was carried out by 1 H- nuclear magnetic resonance spectrum ⁽¹ H-NMR) measurement. 50 mg of liquid crystalline polyester was weighed in an NMR sample tube, dissolved in 800 μL of a solvent (mixed solvent of pentafluorophenol / 1,1,2,2-tetrachloroethane-d ₂ = 65/35 (weight ratio)), and unity INOVA500. ¹ H-NMR measurement was performed at an observation frequency of 500 MHz and a temperature of 80 ° C. using a type NMR apparatus (manufactured by Varian), and the composition was determined from the peak area ratio derived from each structural unit observed in the vicinity of 7 to 9.5 ppm. analyzed.

(2) Melting point (Tm) measurement of liquid crystalline polyester Endothermic peak observed when measuring liquid crystalline polyester from room temperature to 20 ° C./min with a differential scanning calorimeter DSC-7 (manufactured by PerkinElmer). After observing the temperature (Tm ₁ ), holding at a temperature of Tm ₁ + 20 ° C. for 5 minutes, once cooling to room temperature under a temperature drop condition of 20 ° C./min, and measuring again under a temperature rise condition of 20 ° C./min The observed endothermic peak temperature was defined as the melting point (Tm). In the following production examples, the melting point is described as Tm.

(3) Melt viscosity measurement of liquid crystalline polyester Koka type flow tester CFT-500D (orifice 0.5φ × 10 mm) (manufactured by Shimadzu Corporation), Koka type flow tester set to the melting point of liquid crystalline polyester + 20 ° C. In the furnace, the liquid crystalline polyester was melted in order to melt the liquid crystalline polyester, held for 5 minutes, and then the melt viscosity was measured at a shear rate of 1000 / second.

Production Example 1 Liquid crystalline polyester resin (A-1)
In a 5 L reaction vessel equipped with a stirring blade and a distillation tube, 932 parts by weight of p-hydroxybenzoic acid, 251 parts by weight of 4,4′-dihydroxybiphenyl, 99 parts by weight of hydroquinone, 284 parts by weight of terephthalic acid, 90 parts by weight of isophthalic acid And 1252 parts by weight of acetic anhydride (1.09 equivalents of the total phenolic hydroxyl groups) were allowed to react at 145 ° C. for 1 hour with stirring in a nitrogen gas atmosphere, and the jacket temperature was increased from 145 ° C. to 350 ° C. over 4 hours. The temperature was raised. Thereafter, the polymerization temperature was maintained at 350 ° C., the pressure was reduced to 1.0 mmHg (133 Pa) in 1.0 hour, the reaction was continued, and the polymerization was completed when the torque required for stirring reached 20 kg · cm. Next, the inside of the reaction vessel is pressurized to 1.0 kg / cm ² (0.1 MPa), the polymer is discharged onto a strand through a die having a circular discharge port having a diameter of 10 mm, and pelletized by a cutter. Liquid crystalline polyester (A-1) was obtained.

  Composition analysis of this liquid crystalline polyester (A-1) revealed that a structural unit derived from p-hydroxybenzoic acid (structural unit (I)) and a structural unit derived from 4,4′-dihydroxybiphenyl (structural unit (II )) And the structural unit derived from p-hydroxybenzoic acid (structural unit (I)) with respect to the total of the structural unit derived from hydroquinone (structural unit (III)) was 75 mol%. 4,4′-dihydroxybiphenyl-derived structural unit (structural unit (II)) and hydroquinone-derived structural unit (structural unit (III)) relative to the total of 4,4′-dihydroxybiphenyl-derived structural unit (structural unit (II )) Was 60 mol%. The ratio of the structural unit derived from terephthalic acid (structural unit (IV)) to the total of the structural unit derived from terephthalic acid (structural unit (IV)) and the structural unit derived from isophthalic acid (structural unit (V)) is 76 mol%. Met. Total of structural units derived from 4,4′-dihydroxybiphenyl (structural unit (II)) and structural units derived from hydroquinone (structural unit (III)), structural units derived from terephthalic acid (structural unit (IV)) and isophthal The sum of the structural units derived from the acid (structural unit (V)) was substantially equimolar. The Tm was 330 ° C. and the melt viscosity was 28 Pa · s.

Production Example 2 Liquid crystalline polyester (A-2)
870 parts by weight of p-hydroxybenzoic acid, 302 parts by weight of 4,4′-dihydroxybiphenyl, 119 parts by weight of hydroquinone, 247 parts by weight of terephthalic acid, 202 parts by weight of isophthalic acid in a 5 L reaction vessel equipped with a stirring blade and a distillation pipe And 1302 parts by weight of acetic anhydride (1.09 equivalents of the total phenolic hydroxyl groups) were allowed to react at 145 ° C. for 1 hour with stirring under a nitrogen gas atmosphere, and the jacket temperature was increased from 145 ° C. to 330 ° C. in 4 hours. The temperature was raised. Thereafter, the polymerization temperature was maintained at 330 ° C., the pressure was reduced to 1.0 mmHg (133 Pa) in 1.0 hour, the reaction was continued, and the polymerization was completed when the torque required for stirring reached 20 kg · cm. Next, the inside of the reaction vessel is pressurized to 1.0 kg / cm ² (0.1 MPa), the polymer is discharged onto a strand through a die having a circular discharge port having a diameter of 10 mm, and pelletized by a cutter. A liquid crystalline polyester (A-2) was obtained.

  The composition of the liquid crystalline polyester (A-2) was analyzed, and the ratio of the structural unit (I) to the total of the structural unit (I), the structural unit (II), and the structural unit (III) was 70 mol%. there were. The ratio of the structural unit (II) to the total of the structural unit (II) and the structural unit (III) was 60 mol%. The ratio of the structural unit (IV) to the total of the structural unit (IV) and the structural unit (V) was 55 mol%. The total of the structural unit (II) and the structural unit (III) and the total of the structural unit (IV) and the structural unit (V) were substantially equimolar. Moreover, Tm was 310 degreeC and melt viscosity was 30 Pa.s.

Production Example 3 Liquid crystalline polyester (A-3)
In a 5 L reaction vessel equipped with a stirring blade and a distillation pipe, 994 parts by weight of p-hydroxybenzoic acid, 126 parts by weight of 4,4′-dihydroxybiphenyl, 112 parts by weight of terephthalic acid, and an intrinsic viscosity of about 0.6 dl / g 216 parts by weight of polyethylene terephthalate and 960 parts by weight of acetic anhydride (1.10 equivalents of total phenolic hydroxyl groups) were charged, and the mixture was reacted at 145 ° C. for 1 hour with stirring under a nitrogen gas atmosphere. The temperature was raised over time. Thereafter, the polymerization temperature was maintained at 320 ° C., the pressure was reduced to 1.0 mmHg (133 Pa) in 1.0 hour, the reaction was continued, and the polymerization was completed when the torque required for stirring reached 20 kg · cm. Next, the inside of the reaction vessel is pressurized to 1.0 kg / cm ² (0.1 MPa), the polymer is discharged onto a strand through a die having a circular discharge port having a diameter of 10 mm, and pelletized by a cutter. A liquid crystalline polyester (A-3) was obtained.

  Composition analysis of this liquid crystalline polyester (A-3) revealed that the proportion of structural unit (I) was 66.6 mol%, the proportion of structural unit (II) was 6.3 mol%, and ethylene derived from polyethylene terephthalate. The proportion of dioxy units was 10.4 mol% and the proportion of structural units (IV) was 16.7 mol%. Moreover, Tm was 313 degreeC and melt viscosity was 13 Pa.s.

Production Example 4 Liquid crystalline polyester (A-4)
In a 5 L reaction vessel equipped with a stirring blade and a distillation tube, 25 parts by weight of p-hydroxybenzoic acid, 813 parts by weight of 6-hydroxy-2-naphthoic acid, 419 parts by weight of 4,4′-dihydroxybiphenyl, and 374 parts by weight of terephthalic acid And 965 parts by weight of acetic anhydride (1.05 equivalents of total phenolic hydroxyl groups) were allowed to react at 145 ° C. for 1 hour with stirring in a nitrogen gas atmosphere, and then heated from 145 ° C. to 360 ° C. over 4 hours. I let you. Thereafter, the polymerization temperature was maintained at 360 ° C., the pressure was reduced to 1.0 mmHg (133 Pa) in 1.0 hour, the reaction was continued, and the polymerization was completed when the torque required for stirring reached 20 kg · cm. Next, the inside of the reaction vessel is pressurized to 1.0 kg / cm ² (0.1 MPa), the polymer is discharged onto a strand through a die having a circular discharge port having a diameter of 10 mm, and pelletized by a cutter. Liquid crystalline polyester (A-4) was obtained.

  Composition analysis of the liquid crystalline polyester (A-4) revealed that the proportion of the structural unit (I) was 2 mol%, the proportion of the 6-oxy-2-naphthalate unit was 48 mol%, and the structural unit (II) The proportion was 25 mol%, and the proportion of the structural unit (IV) was 25 mol%. The Tm was 350 ° C. and the melt viscosity was 25 Pa · s.

Production Example 5 Liquid crystalline polyester (A-5)
In a 5 L reaction vessel equipped with a stirring blade and a distillation tube, 622 parts by weight of p-hydroxybenzoic acid, 93 parts by weight of 4,4′-dihydroxybiphenyl, 55 parts by weight of hydroquinone, 116 parts by weight of terephthalic acid, 2,6-naphthalene 65 parts by weight of dicarboxylic acid and 622 parts by weight of acetic anhydride (1.00 equivalent of the total phenolic hydroxyl groups) were charged, and the mixture was reacted at 170 ° C. for 1 hour with stirring in a nitrogen gas atmosphere. The temperature was raised over time. Thereafter, the polymerization temperature was maintained at 370 ° C. and the pressure was reduced to 188 mmHg (25 kPa), and then the pressure was reduced to 5.0 mmHg (665 Pa) in 2.0 hours, and polymerization was performed for 1 hour. Next, the inside of the reaction vessel is pressurized to 1.0 kg / cm ² (0.1 MPa), the polymer is discharged onto a strand through a die having a circular discharge port having a diameter of 10 mm, and pelletized by a cutter. Liquid crystalline polyester (A-5) was obtained.

  The composition of the liquid crystalline polyester (A-5) was analyzed. The proportion of the structural unit (I) was 69.2 mol%, the proportion of the structural unit (II) was 7.7 mol%, and the structural unit (III). Of the structural unit (IV) was 10.8 mol%, and the proportion of the 2,6-dinaphthalate unit was 4.6 mol%. The Tm was 350 ° C. and the melt viscosity was 27 Pa · s.

The filler (B) used in each example and comparative example is shown below.
(B-1): Glass milled fiber EPDE-40M-10A (manufactured by Nippon Electric Glass)
(B-2): Mica AB-25S (manufactured by Yamaguchi Mica).

The epoxy compound (C) used in each example and comparative example is shown below.
(C-1): Epoxy equivalent = 253 g / equivalent novolak type epoxy compound (XD-1000, equivalent to the above [Chemical Formula 4] general formulas (VI) and (VIII), manufactured by Nippon Kayaku Co., Ltd.)

(C-2): Epoxy equivalent = 290 g / equivalent novolak type epoxy compound (NC-3000-H, equivalent to the above [Chemical formula 4] general formulas (VI) and (VII), manufactured by Nippon Kayaku Co., Ltd.)

(C-3): Epoxy equivalent = 215 g / equivalent cresol novolac type epoxy compound (Epiclon N-695, manufactured by DIC)
(C-4): Epoxy equivalent = 925 g / equivalent bisphenol A type epoxy compound (jER1004, manufactured by Mitsubishi Chemical)
(C-5): Epoxy equivalent = 170 g / equivalent diglycidyl cyclohexanedicarboxylate (jER191P, manufactured by Mitsubishi Chemical).

Examples 1-12, Comparative Examples 1-10
Liquid crystalline polyesters (A-1) to (A-5) and epoxy compounds (C-1) to (C-5) obtained in each production example using a TEM35B type twin screw extruder manufactured by Toshiba Machine with a side feeder. ) From the original feeder at the blending amount shown in Table 1, and fillers (B-1) to (B-2) from the side feeder at the blending amounts shown in Table 1, Cylinder setting temperature was made into the conditions shown in Table 1, other cylinder temperature was set to melting | fusing point +10 degreeC of liquid crystalline polyester, and it melt-kneaded and was set as the pellet. After the pellets of the obtained liquid crystalline polyester resin composition were dried with hot air, the following evaluations (1) to (3) were performed. The results are shown in Table 1.

(1) Evaluation of heat resistance The liquid crystalline polyester resin composition obtained in each Example and Comparative Example was dried at 150 ° C. for 3 hours using a hot air dryer, and then FANUC α30C injection molding machine (manufactured by FANUC, screw 100 rod-shaped test pieces 100 mm long × 12.7 mm wide × 0.5 mm thick were formed with a cylinder temperature of melting point of liquid crystalline polyester + 20 ° C. and a mold temperature of 90 ° C. The obtained molded product was heat-treated at 260 ° C. for 10 minutes using a hot air dryer, and the number of molded products in which blistering occurred was determined. It was evaluated that the smaller the number of molded products with blistering, the better the heat resistance.

(2) Evaluation of continuous molding stability After drying the liquid crystalline polyester resin composition obtained in each example and comparative example at 150 ° C. for 3 hours using a hot air dryer, a FANUC α30C injection molding machine (manufactured by FANUC) The diameter of the rod was 28 mm, the cylinder temperature was + 20 ° C. of the liquid crystalline polyester, the mold temperature was 90 ° C., and a rod-shaped molded article 127 mm long × 12.7 mm wide × 3.2 mm thick was molded into 50 shots. The standard deviation of 50 shots of the cylinder cushion of each shot at that time (the amount of resin left at the tip of the molding machine cylinder for holding the molded product, expressed as the screw position from the cylinder tip position (0 mm)) It was measured. It was evaluated that the smaller the standard deviation and the smaller the variation in the cushion amount, the better the continuous molding stability.

(3) Evaluation of low water absorption After the liquid crystalline polyester resin composition obtained in each Example and Comparative Example was dried at 150 ° C. for 3 hours using a hot air dryer, a FANUC α30C injection molding machine (manufactured by FANUC, A rod-shaped molded article 127 mm long × 12.7 mm wide × 3.2 mm thick was molded with a cylinder temperature of melting point of liquid crystalline polyester + 20 ° C. and a mold temperature of 90 ° C. The obtained molded product was subjected to wet heat treatment for 150 hours in a constant temperature and humidity chamber (manufactured by ESPEC) at a temperature of 85 ° C. and a relative humidity of 85%, and the average value of the weight change rate before and after the wet heat treatment of five molded products was obtained. . The smaller the weight change rate before and after the wet heat treatment, the better the low water absorption.

  From the results of Table 1, the liquid crystalline polyester resin composition of the embodiment of the present invention has excellent heat resistance, suppresses the occurrence of blistering during heat treatment of the molded product, has excellent continuous molding stability, and has low water absorption. It turns out that it is excellent in property. Therefore, it can be said that it is suitable for use in electrical / electronic component applications.

  The liquid crystalline polyester resin composition of the present invention is useful for electrical and electronic parts because it suppresses the occurrence of blistering during heat treatment of molded products and has excellent continuous molding stability and low water absorption. .

Claims (4)

10-100 parts by weight of filler (B), novolak type, based on 100 parts by weight of liquid crystalline polyester (A) comprising the following structural units (I), (II), (III), (IV) and (V) A liquid crystalline polyester resin composition comprising 0.05 to 5 parts by weight of the epoxy compound (C).

The liquid crystalline polyester resin composition according to claim 1, wherein an epoxy equivalent of the novolac type epoxy compound (C) is 100 to 500 g / equivalent. The liquid crystalline polyester resin composition according to claim 1 or 2, wherein the novolac epoxy compound (C) has a structure represented by the following general formula (VI).

(In the general formula (VI), X represents a divalent group represented by the general formula (VII) or (VIII). In the general formulas (VI) to (VII), R ^{1 to} R ⁴ are Each independently represents an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 10 carbon atoms, and may be the same or different, and R ⁵ is hydrogen, an alkyl group having 1 to 8 carbon atoms or 6 to 6 carbon atoms; Represents an aryl group of 10. In the general formula (VI), n is a natural number of 1 to 10. In the general formulas (VI) to (VII), a, c and d are each independently 0 to 4; Represents an integer, and b represents an integer of 0 to 3.) The molded article formed by shape | molding the liquid crystalline polyester resin composition in any one of Claims 1-3.