Liquid crystal polymer composition

Abstract

An object of the present invention is to provide a liquid crystal polymer composition having improved thin-wall fluidity and excellent blister resistance while maintaining the mechanical strength and heat resistance of the liquid crystal polymer. 【Solution means】The present invention relates to a liquid crystal polymer composition containing 0.1 to 150 parts by mass of talc having a quartz content of 0 to 0.25% by mass and 0.1 to 100 parts by mass of glass fiber with respect to 100 parts by mass of the liquid crystal polymer.

Description

Technical Field

[0001] The present invention relates to a liquid crystal polymer composition having improved thin-wall fluidity and excellent blister resistance while maintaining the mechanical strength and heat resistance of the liquid crystal polymer.

Background Art

[0002] Liquid crystal polymers have excellent moldability and high heat resistance, and are mainly used for applications such as connectors, relays, and bobbins by taking advantage of these characteristics. In recent years, the high integration, miniaturization, thinning, and flattening of electronic components have been progressing. Among them, in connector components, the trend of miniaturization and thinning is remarkable.

[0003] Typical examples of such thin connectors include board-to-board connectors used for joining printed wiring boards and FPC connectors used for connecting flexible printed circuits (FPCs) to printed wiring boards.

[0004] Board-to-board connectors and FPC connectors are required to have heat resistance to withstand reflow soldering, and as electronic devices using printed wiring boards are miniaturized, miniaturization of the components themselves is demanded. For example, narrow pitch connectors with a pitch between the metal terminals of the connector of 0.3 mm to 0.4 mm are provided. In addition, thin connectors with a stacking height of 0.6 mm when the connector is inserted are also provided.

[0005] However, in order to meet the requirements of miniaturization and thinning, there is a risk of short shots caused by insufficient fluidity of the resin during the molding of the connector. Therefore, further improvement in the fluidity of the resin (thin-wall fluidity) in the thin-walled portion of the molded product is required.

[0006] In addition, when the molded product is left in a high-temperature atmosphere for a long time or when soldering is performed, etc., swelling called blisters may occur on the surface. Although the cause of this phenomenon is not clear, air entrapped during the molding of the liquid crystal polymer or oligomer components contained in the resin are brought into the molded product, and then when high-temperature heat treatment is performed, expansion of the air and gasification of the oligomer components occur, pushing up the surface of the molded product softened by heating and appearing as blisters.

[0007] As described above, the liquid crystal polymer, which is a forming material for thin connectors typified by board-to-board connectors and FPC connectors, is required to have improved thin-wall fluidity and excellent blister resistance while maintaining the properties of the liquid crystal polymer such as mechanical strength and heat resistance.

[0008] Patent Document 1 proposes a liquid crystalline polyester composition capable of obtaining a molded body in which gas generation is sufficiently reduced to the extent that blister abnormalities and the like can be suppressed while having high fluidity and anisotropy relaxation of the liquid crystalline polyester by containing a specific terphenyl and a liquid crystalline polyester. However, the fluidity of the resin composition was not sufficient and there was room for improvement.

[0009] Patent Document 2 proposes a liquid crystalline polyester resin composition that maintains high fluidity, is excellent in rigidity at high temperatures, and can reduce the generation of blisters by containing a specific liquid crystalline polyester and a plate-like filler in a predetermined ratio. However, the blister resistance of the resin composition was not sufficient and there was room for improvement.

[0010] In order to improve the thin-wall fluidity, there is a method of lowering the viscosity of the resin, but doing so makes it easier to entrap air inside the molded product during molding, and as a result, blisters are more likely to occur. Thus, although various studies have been conducted on liquid crystal polymer compositions, it has been considered difficult to obtain a liquid crystal polymer composition that is excellent in blister resistance while improving thin-wall fluidity.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0012] The present invention has been made in view of the above circumstances, and an object thereof is to provide a liquid crystal polymer composition having improved thin-wall fluidity and excellent blister resistance while maintaining the mechanical strength and heat resistance of the liquid crystal polymer.

Means for Solving the Problems

[0013] As a result of intensive studies in view of the above problems, the present inventors have found that by blending a specific amount of a specific talc and glass fiber with a liquid crystal polymer, the thin-wall fluidity is improved while maintaining the mechanical strength and heat resistance of the liquid crystal polymer, and a liquid crystal polymer composition excellent in blister resistance can be obtained, and thus the present invention has been completed.

[0014] That is, the present invention includes the following preferred embodiments. 〔1〕A liquid crystal polymer composition containing 0.1 to 150 parts by mass of talc having a quartz content of 0 to 0.25% by mass and 0.1 to 100 parts by mass of glass fiber with respect to 100 parts by mass of the liquid crystal polymer. 〔2〕The liquid crystal polymer composition according to 〔1〕, wherein the liquid crystal polymer contains a repeating unit represented by formula (I) and / or formula (II)

Chemical Formula

[10] A molded article composed of the liquid crystal polymer composition according to any one of [1] to [9]. The molded article according to

[10] is a component that constitutes one selected from the group consisting of a connector, a switch, a relay, a bobbin, a capacitor, a coil, a motor, a fan, a test socket, a transformer, a camera module, and an antenna.

Advantages of the Invention

[0015] The liquid crystal polymer composition of the present invention maintains the mechanical strength and heat resistance of the liquid crystal polymer, and is excellent in thin-wall fluidity and blister resistance. Therefore, it is suitably used for various applications of electrical and electronic components of various communication devices and electronic devices, such as connectors, switches, relays, bobbins, capacitors, coils, motors, fans, test sockets, transformers, camera modules, and antennas.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0017] The liquid crystal polymer (hereinafter also referred to as LCP) used in the liquid crystal polymer composition of the present invention is a polyester or polyester amide that forms an anisotropic molten phase, and is not particularly limited as long as it is called a thermotropic liquid crystal polyester or thermotropic liquid crystal polyester amide in the technical field.

[0018] The properties of the anisotropic molten phase of the liquid crystal polymer can be confirmed by a normal polarization inspection method using a crossed polarizer, that is, by observing a sample placed on a hot stage in a nitrogen atmosphere.

[0019] As the liquid crystal polymer used in the present invention, those having a crystal melting temperature measured by a differential scanning calorimeter of 220 to 380 °C are preferred, those having a crystal melting temperature of 260 to 370 °C are more preferred, those having a crystal melting temperature of 290 to 360 °C are even more preferred, and those having a crystal melting temperature of 310 to 350 °C are particularly preferred.

[0020] If the crystal melting temperature of the liquid crystal polymer is lower than 220 °C, the heat resistance is poor, and if it exceeds 380 °C, the moldability tends to decrease, which is not preferable.

[0021] In addition, in this specification and the claims, the "crystal melting temperature" is determined from the peak temperature of the crystal melting temperature measured by a differential scanning calorimeter (hereinafter abbreviated as DSC) at a heating rate of 20 °C / min. More specifically, after observing the endothermic peak temperature (Tm1) observed when measuring a sample of the liquid crystal polymer under heating conditions of 20 °C / min from room temperature, the sample is held at a temperature 20 to 50 °C higher than Tm1 for 10 minutes, and then, after cooling the sample to room temperature under cooling conditions of 20 °C / min, the endothermic peak observed when measuring again under heating conditions of 20 °C / min is observed, and the temperature indicating the peak top is defined as the crystal melting temperature (Tm) of the liquid crystal polymer. As the measuring device, for example, DSC7020 manufactured by Hitachi High-Tech Science Corporation can be used.

[0022] Examples of the polymerizable monomer constituting the structural unit of the liquid crystal polymer in the present invention include aromatic hydroxycarboxylic acid, aromatic dicarboxylic acid, aromatic diol, aromatic aminocarboxylic acid, aromatic hydroxyamine, aromatic diamine, aliphatic diol, and aliphatic dicarboxylic acid. Such polymerizable monomers may be used alone or in combination of two or more polymerizable monomers. Preferably, a polymerizable monomer having at least one hydroxy group and a carboxyl group is used. Further, the liquid crystal polymer in the present invention is more preferably a liquid crystal polymer composed only of aromatic monomers and containing no aliphatic monomers.

[0023] Specific examples of the aromatic hydroxycarboxylic acid include 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 2-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 5-hydroxy-2-naphthoic acid, 7-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 4'-hydroxyphenyl-4-benzoic acid, 3'-hydroxyphenyl-4-benzoic acid, 4'-hydroxyphenyl-3-benzoic acid, and their alkyl, alkoxy or halogen substituents, as well as ester-forming derivatives such as their acylates, ester derivatives, acid halides and the like. Among these, from the viewpoint of easily adjusting the heat resistance, mechanical strength and melting point of the obtained liquid crystal polymer, 4-hydroxybenzoic acid and / or 6-hydroxy-2-naphthoic acid are preferred.

[0024] Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4,4'-dicarboxybiphenyl, 3,4'-dicarboxybiphenyl and 4,4''-dicarboxytriphenyl, and their alkyl, alkoxy or halogen substituents, as well as their ester derivatives, ester-forming derivatives such as acid halides and the like. Among these, from the viewpoint of effectively enhancing the heat resistance of the obtained liquid crystal polymer, one or more compounds selected from the group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid are preferred, and terephthalic acid and / or 2,6-naphthalenedicarboxylic acid are more preferred.

[0025] Specific examples of the aromatic diol include hydroquinone, resorcinol, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, 2,2'-dihydroxybinaphthyl, alkyl, alkoxy or halogen substituents thereof, and ester-forming derivatives such as their acylates. Among these, from the viewpoint of excellent reactivity during polymerization, one or more compounds selected from the group consisting of hydroquinone, resorcinol, 4,4'-dihydroxybiphenyl and 2,6-dihydroxynaphthalene are preferred, and hydroquinone and / or 4,4'-dihydroxybiphenyl are more preferred.

[0026] Specific examples of the aromatic aminocarboxylic acid include 4-aminobenzoic acid, 3-aminobenzoic acid, 6-amino-2-naphthoic acid, alkyl, alkoxy or halogen substituents thereof, and ester-forming derivatives such as their acylates, ester derivatives, acid halides.

[0027] Specific examples of the aromatic hydroxyamine include 4-aminophenol, N-methyl-4-aminophenol, 3-aminophenol, 3-methyl-4-aminophenol, 4-amino-1-naphthol, 4-amino-4'-hydroxybiphenyl, 4-amino-4'-hydroxybiphenyl ether, 4-amino-4'-hydroxybiphenyl methane, 4-amino-4'-hydroxybiphenyl sulfide and 2,2'-diaminobinaphthyl, alkyl, alkoxy or halogen substituents thereof, and ester-forming derivatives such as their acylates. Among these, 4-aminophenol is preferred from the viewpoint of easily achieving a balance between the heat resistance and mechanical strength of the resulting liquid crystal polymer.

[0028] Specific examples of the aromatic diamine include 1,4-phenylenediamine, 1,3-phenylenediamine, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, alkyl, alkoxy or halogen substituents thereof, and amide-forming derivatives such as acylates thereof.

[0029] Specific examples of the aliphatic diol include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, and acylates thereof. Further, a polymer containing an aliphatic diol such as polyethylene terephthalate or polybutylene terephthalate may be reacted with the above aromatic oxycarboxylic acid, aromatic dicarboxylic acid, aromatic diol and their acylates, ester derivatives, acid halides, etc.

[0030] Specific examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid, fumaric acid, maleic acid and hexahydroterephthalic acid. Among these, oxalic acid, succinic acid, adipic acid, suberic acid, sebacic acid and dodecanedioic acid are preferred from the viewpoint of excellent reactivity during polymerization.

[0031] The polymerizable monomer forming the constitutional unit of the liquid crystal polymer in the present invention may contain, as other copolymerization components, dihydroxyterephthalic acid, 4-hydroxyisophthalic acid, 5-hydroxyisophthalic acid, trimellitic acid, 1,3,5-benzenetricarboxylic acid, pyromellitic acid or their alkyl, alkoxy or halogen substituents, and ester-forming derivatives such as acylates, ester derivatives, acid halides thereof, etc., within a range not impairing the object of the present invention. The amount of these polymerizable monomers used is preferably such that it is 10 mol% or less with respect to all the constitutional units constituting the liquid crystal polymer.

[0032] In the present invention, the liquid crystal polymer may contain a thioester bond as long as the object of the present invention is not impaired. Examples of the polymerizable monomer that provides such a bond include mercapto aromatic carboxylic acid, aromatic dithiol, and hydroxy aromatic thiol. The content of these polymerizable monomers is preferably an amount such that it is 10 mol% or less with respect to all the constituent units constituting the liquid crystal polymer.

[0033] Among the polymers obtained by combining these repeating units, there are those that form a nematic molten phase and those that do not form a nematic molten phase depending on the constitution and composition ratio of the monomers and the sequence distribution of each repeating unit in the polymer. However, the liquid crystal polymer used in the present invention is limited to those that form a nematic molten phase.

[0034] Specific examples of the combination of polymerizable monomers that form the constituent units of the liquid crystal polymer used in the present invention include, for example, the following. 1) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid, 2) 4-Hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl, 3) 4-Hydroxybenzoic acid / terephthalic acid / isophthalic acid / 4,4'-dihydroxybiphenyl, 4) 4-Hydroxybenzoic acid / terephthalic acid / isophthalic acid / 4,4'-dihydroxybiphenyl / hydroquinone, 5) 4-Hydroxybenzoic acid / terephthalic acid / hydroquinone, 6) 6-Hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone, 7) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl, 8) 6-Hydroxy-2-naphthoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl, 9) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone, 10) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone / 4,4'-dihydroxybiphenyl, 11) 4-Hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / 4,4'-dihydroxybiphenyl, 12) 4-Hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone, 13) 4-Hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone, 14) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone, 15) 4-Hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone / 4,4'-dihydroxybiphenyl, 16) 4-Hydroxybenzoic acid / terephthalic acid / 4-aminophenol, 17) 6-Hydroxy-2-naphthoic acid / terephthalic acid / 4-aminophenol, 18) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4-aminophenol, 19) 4-Hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / 4-aminophenol, 20) 4-Hydroxybenzoic acid / terephthalic acid / ethylene glycol, 21) 4-Hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / ethylene glycol, 22) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / ethylene glycol, 23) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / ethylene glycol, 24) 4-Hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / 4,4'-dihydroxybiphenyl.

[0035] Among these, a liquid crystal polymer composed of constitutional units derived from the polymerizable monomers of 1), 2), 3), 7), 9), 10), and 14) is preferable, a liquid crystal polymer composed of constitutional units derived from the polymerizable monomers of 9), 10), and 14) is more preferable, and a liquid crystal polymer composed of constitutional units derived from the polymerizable monomer of 10) is even more preferable.

[0036] In one preferred embodiment, the liquid crystal polymer used in the liquid crystal polymer composition of the present invention is, in terms of excellent fluidity and mechanical properties, represented by formula (I) and / or formula (II)

Chemical formula

[0037] In the above liquid crystal polymer containing repeating units represented by formula (I) and / or formula (II), in terms of excellent fluidity and heat resistance, it is further Formula (III) and Formula preferably contains repeating units represented by (IV).

Chemical formula

[0038] Here, the repeating unit represented by formula (III) may be a plurality of repeating units each containing a different Ar1, and the repeating unit represented by formula (IV) may be a plurality of repeating units each containing a different Ar2. That is, the repeating unit represented by formula (III) may be a plurality of repeating units such as a repeating unit having a certain type of Ar1 and a repeating unit having another type of Ar1, and similarly, the repeating unit represented by formula (IV) may be a plurality of repeating units such as a repeating unit having a certain type of Ar2 and a repeating unit having another type of Ar2. Also, the "aromatic group" refers to an aromatic group that is a 6-membered monocyclic ring (including a biphenyl structure) or a condensed ring having 2 rings.

[0039] In terms of excellent fluidity and mechanical properties, the composition ratio (mol%) of the repeating units represented by formula (I) and / or formula (II) is preferably 30 to 80 mol%, more preferably 40 to 70 mol%. For each of the repeating units represented by formula (III) and formula (IV), 10 to 35 mol% is preferably, and 15 to 30 mol% is more preferably. The repeating units represented by formula (III) and formula (IV) are preferably in substantially equimolar amounts.

[0040] As another preferred embodiment, further Formula (III) and Formula In the liquid crystal polymer containing the repeating units represented by (IV), in terms of excellent fluidity and mechanical properties, it is preferable to contain both of the repeating units represented by formula (I) and formula (II).

Chemical formula

[0041] In terms of excellent fluidity and mechanical properties, the total composition ratio (mol%) of the repeating units represented by formula (I) and formula (II) is preferably 30 to 80 mol%, more preferably 35 to 60 mol%. The repeating unit represented by formula (II) is preferably 0.1 to 30 mol%, more preferably 0.5 to 25 mol%, and even more preferably 1 to 20 mol%. For each of the repeating units represented by formula (III) and formula (IV), 10 to 35 mol% is preferably, and 20 to 32.5 mol% is more preferably. The repeating units represented by formula (III) and formula (IV) are preferably in substantially equimolar amounts.

[0042] In terms of excellent fluidity and heat resistance, the repeating units represented by formulas (III) to (IV) are more preferably each one or more repeating units in which Ar1 and Ar2 are each independently selected from aromatic groups represented by the following formulas (1) to (4). The repeating unit represented by formula (III) is a repeating unit in which Ar1 is an aromatic group represented by formula (1) and / or formula (3), and the repeating unit represented by formula (IV) is particularly preferably a repeating unit in which Ar2 is an aromatic group represented by one or more selected from the group consisting of formulas (1), (2), and (4).

Chemical formula

[0043] Hereinafter, the method for producing the liquid crystal polymer used in the present invention will be described.

[0044] There is no particular limitation on the method for producing the liquid crystal polymer used in the present invention, and a liquid crystal polymer can be obtained by subjecting a polymerizable monomer to a known polycondensation method for forming an ester bond or an amide bond, such as a melt acidolysis method, a slurry polymerization method, or the like.

[0045] The melt acidolysis method is a preferable method for producing the liquid crystal polymer used in the liquid crystal polymer composition of the present invention. This method first heats the polymerizable monomer to form a molten solution of the reaction substance, and then continues the polycondensation reaction to obtain a molten polymer. In addition, a vacuum may be applied in order to facilitate the removal of volatile substances (such as acetic acid, water, etc.) by-produced in the final stage of condensation.

[0046] The slurry polymerization method is a method in which a polymerizable monomer is reacted in the presence of a heat exchange fluid, and the solid product is obtained in a state of being suspended in the heat exchange medium.

[0047] In both the melt acidolysis method and the slurry polymerization method, the polymerizable monomer used in producing the liquid crystal polymer can also be subjected to the reaction in a modified form in which the hydroxyl group and / or amino group is acylated at room temperature, that is, as a lower acyl compound.

[0048] The lower acyl group preferably has 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms. In a preferred embodiment of the present invention, the acetylated product of the polymerizable monomer is subjected to the reaction.

[0049] As the lower acyl compound of the polymerizable monomer, those separately acylated and pre-synthesized may be used, or an acylating agent such as acetic anhydride may be added to the polymerizable monomer during the production of the liquid crystal polymer to generate it in the reaction system.

[0050] In both the melt acidolysis method and the slurry polymerization method, the polycondensation reaction is preferably carried out at a temperature of 150 to 400°C, more preferably 250 to 370°C, under normal pressure and / or reduced pressure, and a catalyst may be used as necessary.

[0051] Specific examples of the catalyst include organotin compounds such as dialkyltin oxide (e.g., dibutyltin oxide) and diaryltin oxide; titanium dioxide; antimony trioxide; organotitanium compounds such as alkoxytitanium silicate and titanium alkoxide; alkali and alkaline earth metal salts of carboxylic acids (e.g., sodium acetate, potassium acetate); gaseous acid catalysts such as Lewis acids (e.g., boron trifluoride) and hydrogen halides (e.g., hydrogen chloride).

[0052] When using a catalyst, the amount of the catalyst is preferably 1 to 1000 ppm, more preferably 2 to 100 ppm, based on the total amount of the polymerizable monomer.

[0053] The liquid crystal polymer obtained by such a polycondensation reaction is usually processed into pellets, flakes, or powder after being withdrawn from the polymerization reaction tank in a molten state, and is subjected to melt kneading with other components.

[0054] The pellet-shaped, flake-shaped, or powdery liquid crystal polymer may be heat-treated in a substantially solid state under reduced pressure, under vacuum, or in an atmosphere of an inert gas such as nitrogen or helium for the purpose of increasing the molecular weight and improving the heat resistance.

[0055] The temperature of the heat treatment is not particularly limited as long as the liquid crystal polymer does not melt, but is preferably 260 to 350°C, more preferably 280 to 320°C.

[0056] The melt viscosity of the liquid crystal polymer used in the present invention (measured with a capillary rheometer, crystal melting temperature + 10 to 30°C, 1000 s -1 ) is preferably 1 to 200 Pa·s, more preferably 3 to 100 Pa·s, even more preferably 4 to 80 Pa·s, and particularly preferably 5 to 40 Pa·s.

[0057] When the melt viscosity is less than 1 Pa·s, drooling and stringing phenomena tend to occur easily during injection molding, and when it exceeds 200 Pa·s, the fluidity tends to decrease.

[0058] The average particle diameter of the talc used in the liquid crystal polymer composition of the present invention is preferably 0.1 to 100 μm, more preferably 0.5 to 80 μm, and even more preferably 3 to 50 μm. In this specification, the average particle diameter refers to the volume-based median diameter (median diameter) measured by the laser diffraction / scattering particle size distribution measurement method.

[0059] The talc used in the present invention preferably has a quartz content in a powder X-ray diffractometer measured by the method described below of 0 to 0.25% by mass, more preferably 0.20% by mass or less, still more preferably 0.15% by mass or less, particularly preferably 0.10% by mass or less, and most preferably 0.05% by mass or less. The closer the quartz content is to 0% by mass, the better the blister resistance and fluidity. When it exceeds 0.25% by mass, the blister resistance or fluidity tends to decrease. In the present invention, quartz is silicon dioxide having a crystal structure (crystalline silica), also referred to as quartz. The method described below for evaluating the quartz content in talc using a powder X-ray diffractometer can also be applied to substances other than talc.

[0060] The above talc may be used after being treated with a known surface treatment agent.

[0061] In the liquid crystal polymer composition of the present invention, the talc content is 0.1 to 150 parts by mass, preferably 1 to 100 parts by mass, more preferably 5 to 80 parts by mass, and still more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the liquid crystal polymer. Formula When the content is less than 0.1 part by mass, the blister resistance tends to be insufficient. When it exceeds 150 parts by mass, the fluidity tends to decrease.

[0062] The glass fiber used in the liquid crystal polymer composition of the present invention preferably has a number average fiber diameter of 0.1 to 50 μm and a number average fiber length of 20 μm to 10 mm.

[0063] Examples of the glass fiber used in the present invention include those produced by various methods such as long fiber type chopped glass fiber and short fiber type milled glass fiber. Two or more of these can also be used in combination.

[0064] Examples of the types of glass fibers used in the present invention include E-glass, A-glass, C-glass, D-glass, AR-glass, R-glass, S-glass, and mixtures thereof. Among these, E-glass is preferred because of its excellent strength and easy availability.

[0065] The glass fibers used in the present invention may be treated with a coupling agent such as a silane-based coupling agent or a titanium-based coupling agent, if necessary.

[0066] The glass fibers used in the present invention may be coated with a thermoplastic resin such as a urethane resin, an acrylic resin, or an ethylene / vinyl acetate copolymer, or treated with a heat-curable resin such as an epoxy resin or a sizing agent.

[0067] The number average fiber diameter of the glass fibers used in the present invention is preferably 3 to 20 μm, more preferably 5 to 16 μm, and even more preferably 7 to 13 μm. The resulting liquid crystal Polymer The number average fiber diameter of the glass fibers in the composition does not substantially change even after melt-kneading.

[0068] The raw material glass fibers to be used preferably have a cut fiber length of 10 mm or less. When the glass fibers are chopped glass fibers of the long fiber type, 1.5 to 6 mm is more preferable, and 2 to 4 mm is even more preferable. When the glass fibers are milled glass fibers of the short fiber type, 10 μm to 200 μm is more preferable, and 20 to 150 μm is even more preferable. From the viewpoints of easy availability and easy handling, it is preferable to use chopped glass fibers of the long fiber type. The resulting liquid crystal Polymer The number average fiber length of the glass fibers in the composition is preferably 10 to 600 μm, more preferably 30 to 500 μm, and even more preferably 50 to 450 μm. The glass fibers usually Polymer break or crush during blending and kneading with liquid crystals or the like, resulting in the number average fiber length in the above liquid crystal Polymer composition. The liquid crystal containing glass fibers of a desired fiber length PolymerIn order to obtain the composition, the conditions of melt kneading can be set and adjusted according to the cut fiber length of the glass fiber used.

[0069] Note that the number average fiber diameter and number average fiber length of the glass fiber in the liquid crystal polymer composition can be measured by observing with a microscope. First, 1.0 g of the liquid crystal polymer composition is collected in a crucible, treated at 500 to 600 ° C for 5 hours in an electric furnace to be ashed, and the residue is dispersed in methanol and spread on a slide glass to obtain a sample. Next, in the projected image of the glass fiber in the microscope field of view, the length in the longitudinal direction is read as the fiber length, and the length in the direction perpendicular to the longitudinal direction is read as the fiber diameter, and the arithmetic average value is calculated. The population of the average value shall be 200 or more.

[0070] In the liquid crystal polymer composition of the present invention, the content of the glass fiber is 0.1 to 100 parts by mass, preferably 1 to 70 parts by mass, more preferably 3 to 50 parts by mass, still more preferably 5 to 40 parts by mass, and particularly preferably 8 to 30 parts by mass with respect to 100 parts by mass of the liquid crystal polymer. Glass fiber When the content is less than 0.1 part by mass, Glass fiber the effect of improving the strength by using it tends not to be obtained, and when it exceeds 100 parts by mass, the fluidity tends to decrease.

[0071] In the liquid crystal polymer composition of the present invention, the content ratio of talc to glass fiber is preferably 0.5 or more, more preferably 0.7 to 10, still more preferably 0.9 to 7, and particularly preferably 0.95 to 5. When the content ratio of talc / glass fiber is less than 0.5, the blister resistance or fluidity tends to decrease.

[0072] Further, the liquid crystal polymer composition of the present invention can contain, for example, other fibrous, plate-like, granular inorganic fillers or organic fillers in addition to the above-mentioned talc and glass fiber as long as the object of the present invention is not impaired.

[0073] Examples of other fibrous fillers used in the present invention include, for example, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, polyarylate fiber, polybenzimidazole fiber, potassium titanate whisker, aluminum borate whisker, acicular titanium oxide, calcium silicate such as wollastonite, zonotlite, calcium titanate, aluminum borate, acicular calcium carbonate, basalt fiber, tetra-pot type zinc oxide, etc. These can be used alone or in combination of two or more kinds.

[0074] Examples of other plate-like fillers used in the present invention include, for example, mica, kaolin, clay, vermiculite, calcium silicate, aluminum silicate, feldspar powder, acid clay, waxstone clay, sericite, sillimanite, bentonite, glass flake, slate powder, silicate such as silane, calcium carbonate, chalk, barium carbonate, magnesium carbonate, carbonate such as dolomite, barite powder, precipitated calcium sulfate, gypsum, sulfate such as barium sulfate, hydroxide such as hydrated alumina, alumina, antimony oxide, magnesia, titanium oxide, zinc white, silica, silica sand, white carbon, oxide such as diatomaceous earth, sulfide such as molybdenum disulfide, plate-like wollastonite, etc. These can be used alone or in combination of two or more kinds.

[0075] Examples of other granular fillers used in the present invention include, for example, silica, alumina, titanium oxide, calcium carbonate, glass beads, glass balloons, barium sulfate, boron nitride, silicon carbide, and resin beads, etc. These can be used alone or in combination of two or more kinds.

[0076] The content of these other fibrous, plate-like, and granular inorganic fillers or organic fillers is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, based on 100 parts by mass of the liquid crystal polymer. When the content of these other fibrous, plate-like, and granular inorganic fillers or organic fillers exceeds 50 parts by mass, the fluidity tends to decrease.

[0077] In addition, the liquid crystal polymer composition of the present invention can contain other additives as long as the effects of the present invention are not impaired.

[0078] Examples of other additives used in the present invention include, for example, higher fatty acids, higher fatty acid esters, higher fatty acid amides, higher fatty acid metal salts (where the higher fatty acid refers to, for example, those having 10 to 25 carbon atoms) which are lubricants, polysiloxanes, fluororesins, etc. which are mold release improvers, dyes, pigments, carbon black, etc. which are colorants, flame retardants, antistatic agents, surfactants, phosphorus-based antioxidants, phenolic antioxidants, sulfur-based antioxidants, etc. which are antioxidants, weathering agents, heat stabilizers, neutralizing agents, and the like. These additives may be used alone or in combination of two or more.

[0079] The content of these other additives is preferably 10 parts by mass or less, more preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the liquid crystal polymer. When the content of these other additives exceeds 10 parts by mass, the thermal stability tends to deteriorate.

[0080] For those having an external lubricant effect such as higher fatty acids, higher fatty acid esters, higher fatty acid metal salts, fluorocarbon-based surfactants, etc., when molding the liquid crystal polymer composition, they may be attached to the surface of the pellets of the liquid crystal polymer composition in advance.

[0081] In addition, the liquid crystal polymer composition of the present invention may further contain other resin components as long as the object of the present invention is not impaired. Examples of other resin components include, for example, polyamides, polyesters, polyacetals, polyphenylene ethers and their modified products, polysulfones, polyethersulfones, polyetherimides, polyamideimides, elastomers, etc. which are thermoplastic resins, and phenolic resins, epoxy resins, polyimide resins, etc. which are thermosetting resins.

[0082] Other resin components can be contained alone or in combination of two or more. The content of other resin components is not particularly limited and may be appropriately determined according to the use and purpose of the liquid crystal polymer composition. Typically, the total content of other resins with respect to 100 parts by mass of the liquid crystal polymer is preferably added in the range of 100 parts by mass or less, particularly 50 parts by mass or less.

[0083] The liquid crystal polymer, talc and glass fiber, and if desired, other inorganic fillers and / or organic fillers, other additives, other resin components, etc. are blended in a predetermined composition and melt-kneaded using a Banbury mixer, kneader, single-screw or twin-screw extruder, etc. to obtain a liquid crystal polymer composition.

[0084] The liquid crystal polymer composition of the present invention thus obtained is molded or processed by a known molding method using an injection molding machine, an extruder, etc.

[0085] The liquid crystal polymer composition of the present invention preferably has a tensile strength of 80 MPa or more, more preferably 90 MPa or more, and even more preferably 100 MPa or more in a tensile test conducted in accordance with ASTM D638 using an ASTM No. 4 dumbbell test piece with a thickness of 3.2 mm. When the tensile strength is less than 80 MPa, there is a tendency to be easily damaged when used as a small and thin-walled part. The upper limit value of the above tensile strength is not particularly limited, but is, for example, 250 MPa.

[0086] The liquid crystal polymer composition of the present invention preferably has an elongation at break of 1% or more, more preferably 2% or more, and even more preferably 2.5% or more in a tensile test conducted in accordance with ASTM D638 using an ASTM No. 4 dumbbell test piece with a thickness of 3.2 mm. When the elongation at break is less than 1%, there is a tendency to be easily damaged when used as a small and thin-walled part. The upper limit value of the above elongation at break is not particularly limited, but is, for example, 10%.

[0087] In the Izod impact test in accordance with ASTM D256 using a strip-shaped test piece with a notched length of 63.5 mm, a width of 12.7 mm, and a thickness of 3.2 mm, the Izod impact strength of the liquid crystal polymer composition of the present invention is preferably 25 J / m or more, more preferably 50 J / m or more, still more preferably 100 J / m or more, and particularly preferably 150 J / m or more. When the Izod impact strength is less than 25 J / m, it tends to be easily damaged when used as a small and thin component. The upper limit value of the Izod impact strength is not particularly limited, but is, for example, 600 J / m.

[0088] The liquid crystal polymer composition of the present invention preferably uses a strip-shaped test piece (length 127 mm, width 12.7 mm) with a thickness of 3.2 mm, and the heat distortion temperature (DTUL, load 1.82 MPa) in accordance with ASTM D648 is 220°C or higher, more preferably 230°C or higher, and still more preferably 240°C or higher. When the heat distortion temperature is less than 220°C, deformation is likely to occur in the reflow process, which is a processing step of electronic components, and the heat resistance tends to be inferior. The upper limit value of the heat distortion temperature is not particularly limited, but is, for example, 320°C.

[0089] The liquid crystal polymer composition of the present invention has a melt viscosity measured at a temperature of the crystal melting temperature + 10 to 30°C by a melt viscosity measuring device having a capillary of 1.0 mmφ × 10 mm, preferably 3 to 70 Pa·s, more preferably 5 to 50 Pa·s, and still more preferably 10 to 40 Pa·s. When the melt viscosity is less than 3 Pa·s, problems such as drooling are likely to occur during injection molding, and when it exceeds 70 Pa·s, the fluidity tends to be insufficient.

[0090] The liquid crystal polymer composition of the present invention preferably has a flow length at a thickness of 0.1 mm measured by the method described below of 7 mm or more, more preferably 8 mm or more, still more preferably 9 mm or more, and particularly preferably 10 mm or more. When the flow length at a thickness of 0.1 mm is less than 7 mm, problems such as short shots are likely to occur when molding small and thin components. The upper limit value of the flow length at a thickness of 0.1 mm is not particularly limited, but is, for example, 50 mm.

[0091] In the liquid crystal polymer composition of the present invention, the blister generation rate in the step blister test measured by the method described below is preferably 15% or less, more preferably 10% or less, still more preferably 5% or less. The lower the generation rate and the closer it is to 0%, the better the blister resistance. Since this test is a severe test, if the blister generation rate in this test is 15% or less, it has sufficient practicality. When the blister generation rate exceeds 15%, blisters may occur even in actual use depending on the molding conditions.

[0092] In the liquid crystal polymer composition of the present invention, the quartz content with respect to the entire liquid crystal polymer composition is preferably 0 to 0.040% by mass or less, more preferably 0.030% by mass or less, still more preferably 0.020% by mass or less, and particularly preferably 0.010% by mass or less. When the quartz content exceeds 0.040% by mass, the blister resistance or fluidity tends to be inferior. The quartz content in the liquid crystal polymer composition can be calculated according to the content ratio by previously measuring the quartz content of each substance such as inorganic fillers such as talc contained in the liquid crystal polymer composition. Alternatively, as another method, 1.0 g of the liquid crystal polymer composition is sampled into a crucible, treated at 500 to 600 ° C. for 5 hours in an electric furnace to be ashed, the mass of the obtained residue is measured, and the amount of quartz contained in the residue is calculated and evaluated by measuring the residue by the method described below using a powder X-ray diffractometer.

[0093] Since the liquid crystal polymer composition of the present invention is excellent in thin-wall fluidity and blister resistance while maintaining the mechanical strength and heat resistance of the liquid crystal polymer, it can be used as a molded product, and is particularly suitable for electronic components such as connectors, switches, relays, bobbins, capacitors, coils, motors, fans, test sockets, transformers, camera modules, and antennas.

Examples

[0094] Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to the following examples.

[0095] In the examples, the measurement and evaluation of the crystal melting temperature, tensile strength, tensile elongation at break, Izod impact strength, heat distortion temperature, melt viscosity, flow length at 0.1 mm thickness, step blister, and quartz content in talc were carried out by the methods described below.

[0096] (1) Crystal melting temperature Using a differential scanning calorimeter (DSC7020 manufactured by Hitachi High-Tech Science Corporation), after observing the endothermic peak temperature (Tm1) measured under the temperature rising condition of 20 °C / min from room temperature, it was held at a temperature 20 to 50 °C higher than Tm1 for 10 minutes. Then, the sample was cooled to room temperature under the temperature decreasing condition of 20 °C / min, and the temperature at the peak top of the exothermic peak observed at that time was defined as the crystallization temperature (Tc) of the liquid crystal polymer. Furthermore, the endothermic peak was observed again when measured under the temperature rising condition of 20 °C / min, and the temperature indicating the peak top was defined as the crystal melting temperature (Tm) of the liquid crystal polymer.

[0097] (2) Tensile strength Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industrial Co., Ltd.), injection molding was carried out at a cylinder temperature of the crystal melting temperature + 10 to 30 °C and a mold temperature of 70 °C to obtain dumbbell-shaped tensile test pieces (ASTM No. 4, thickness 3.2 mm). The tensile test was measured using an autograph AG-X plus manufactured by Shimadzu Corporation, in accordance with ASTM D638, with a span distance of 64.0 mm and a tensile speed of 5 mm / min.

[0098] (3) Tensile elongation at break Using the same test pieces as those used for the measurement of the tensile strength, the measurement was carried out under the same conditions as the tensile strength.

[0099] (4) Izod impact strength Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industrial Co., Ltd.), strip-shaped test pieces with a length of 127 mm, a width of 12.7 mm, and a thickness of 3.2 mm were molded at a cylinder temperature of 350 °C and a mold temperature of 70 °C. The center of this test piece was cut perpendicular to the length direction to obtain strip-shaped test pieces with a length of 63.5 mm, a width of 12.7 mm, and a thickness of 3.2 mm. After notching, the measurement was carried out in accordance with ASTM D256.

[0100] (5) Heat Deflection Temperature under Load (DTUL) Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industrial Co., Ltd.), at a cylinder temperature of the melting temperature of the crystal + 10 to 30 °C and a mold temperature of 70 °C, it was molded into a strip-shaped test piece with a length of 127 mm, a width of 12.7 mm, and a thickness of 3.2 mm. Using this, in accordance with ASTM D648, it was measured at a load of 1.82 MPa and a heating rate of 2 °C / min.

[0101] (6) Melt Viscosity Using a melt viscosity measuring device (Capillograph 1D manufactured by Toyo Seiki Seisaku-sho, Ltd.), with a capillary of 1.0 mmφ × 10 mm, the melt viscosity was measured under the conditions of a shear rate of 1000 sec -1 and a temperature of 350 °C.

[0102] (7) Flow Length at 0.1 mm Thickness Using a rectangular bar flow mold with a length of 50 mm, a width of 2.0 mm, and a thickness of 0.1 mm, injection molding was performed using an injection molding machine (NEX-15-1E manufactured by Nissei Plastic Industrial Co., Ltd.) under the molding conditions shown in Table 1, and the flow length when filling the bar flow mold was measured.

[0103]

Table 1

[0104] (8) Step Blister Using an injection molding machine (NEX-15-1E manufactured by Nissei Plastic Co., Ltd.), injection molding was performed under the molding conditions shown in Table 2 to produce a plate-shaped test piece. This plate-shaped test piece has a plate-shaped portion with a length of 24 mm × a width of 16 mm × a thickness of 0.3 mm. On one side plane portion, a total of 6 locations (arranged in 3 rows in the vertical direction × 2 columns in the horizontal direction), with a 4 mm interval provided between each, are evenly provided with convex portions (a length of 4 mm × a width of 4 mm × a height of 0.5 mm, a total thickness of 0.8 mm). With this shape, during injection molding, it is intentionally shaped to easily entrap air in the resin, making it easy for blisters to occur due to heating and enabling a severe test. After allowing this plate-shaped test piece to stand still for 24 hours under the conditions of 23°C and 50% relative humidity, a reflow process was carried out using an IR reflow apparatus (manufactured by Senju Metal Industry Co., Ltd., SAI-2604) under the conditions of a preheating temperature of 190°C, a preheating time of 30 to 50 seconds, a main heating temperature of 250°C or higher, a main heating time of 20 to 30 seconds, and a peak temperature of 260 to 265°C. After that, the occurrence status of bulges (blisters) on the surface was counted visually. Regarding the counting method, a line was drawn using a writing instrument so as to divide the plate-shaped test piece into six parts centered on six convex portions provided on the plate-shaped test piece, and the presence or absence of blisters was confirmed in each of the six regions. If there was an occurrence of blisters in each region, it was counted as 1, and if not, it was counted as 0. That is, for one plate-shaped test piece, the maximum count number of blisters is 6. For 15 test pieces (90 regions) under one injection speed condition and a total of 60 test pieces (a total of 360 regions) under four injection speed conditions in total, when the occurrence rate of blisters was 0 to 5%, it was rated as ◎; when it was more than 5% to 15%, it was rated as 〇; when it was more than 15% to 25%, it was rated as △; and when it was more than 25%, it was rated as ×.

[0105]

Table 2

[0106] (9) Evaluation of the quartz content contained in talc The quartz content contained in talc was determined as follows using a powder X-ray diffractometer (D8 ADVANCE manufactured by Bruker). Talc with a quartz content extremely close to zero (TP-40B manufactured by Tamura Talc Industry Co., Ltd., described later) and quartz (JAWE4513 manufactured by the Japan Working Environment Measurement Association, SiO2 content 99.6%) were mixed at a certain ratio (a total of six points with quartz ratios of 0.1 mass%, 0.3 mass%, 0.5 mass%, 1.0 mass%, 2.0 mass%, and 3.0 mass%). These were measured using a powder X-ray diffractometer, and a calibration curve was created using the peak intensity of quartz observed in the vicinity of 2θ = 26.6 to 26.7°. After that, talc alone used in the liquid crystal polymer composition was measured using a powder X-ray diffractometer, and the quartz content was calculated by comparing it with the calibration curve.

[0107] The measurement was carried out under the following conditions. X-ray generator: CuKα ray source, voltage 40 kV, current 40 mA Slit: 0.3° Scan step: 0.02° Scan range: 25 - 28° Scan speed: 0.12 deg / min Rotation speed: 15 rpm X-ray detector: One-dimensional semiconductor detector Measurement atmosphere: Atmospheric atmosphere Sample stage: Sample stage for powder measurement (made of PMMA)

[0108] As for talc with a quartz content extremely close to zero, no quartz-derived peak around 2θ of 26.6 - 26.7° was detected in the above measurement. TP-40B manufactured by (Yuki) Tamura Talc Industry Co., Ltd. was selected. Since no quartz-derived peak was detected, the quartz content of TP-40B was set to 0.00% in this example. In addition, if there is talc with a lower peak intensity than TP-40B due to the influence of small noise, etc., the quartz content of these talcs shall also be 0.00%.

[0109] The X-ray diffraction charts of 100% talc with a quartz content extremely close to zero and a mixture of 97% talc and 3% quartz used for preparing the calibration curve are shown in Figure 1. Also, the X-ray diffraction chart for determining the quartz content contained in each talc is shown in Figure 2. In each of the following experimental examples, the quartz content in the liquid crystal polymer composition was calculated from the quartz content in the talc obtained by the above evaluation.

[0110] The synthesis examples of the liquid crystal polymers used in the following examples and comparative examples are described. The abbreviations of the compounds in the synthesis examples are as follows.

[0111] 〔Monomers used for synthesizing liquid crystal polymer (LCP)〕 POB: 4-Hydroxybenzoic acid BON6: 6-Hydroxy-2-naphthoic acid BP: 4,4'-Dihydroxybiphenyl HQ: Hydroquinone TPA: Terephthalic acid NDA: 2,6-Naphthalenedicarboxylic acid

[0112] Synthesis Example 1 (LCP1) In a reaction vessel equipped with a stirring device with a torque meter and a distillation tube, POB, BON6, HQ, BP, and TPA were charged in the composition ratios shown in Table 3 so that the total amount was 6.5 mol. Further, 1.03 times the molar amount of acetic anhydride based on the total amount of hydroxyl groups (mol) of all monomers was charged, and deacetic acid polymerization was carried out under the following conditions.

[0113] [Table 3]

[0114] Under a nitrogen gas atmosphere, the temperature was raised from room temperature to 150 °C over 1 hour and held at the same temperature for 30 minutes. Subsequently, while distilling off the by-produced acetic acid, the temperature was raised to 350 °C over 7 hours, and then the pressure was reduced to 5 mmHg over 80 minutes. When a predetermined torque was shown, the polymerization reaction was terminated, and the contents of the reaction vessel were taken out to obtain pellets of the liquid crystal polymer using a pulverizer. The amount of acetic acid distilled off during polymerization was almost the same as the theoretical value. The crystal melting temperature (Tm) of the obtained pellets was 340 °C.

[0115] Synthesis Example 2 (LCP2) In a reaction vessel equipped with a stirring device with a torque meter and a distillation tube, POB, BON6, HQ, and TPA were charged in the composition ratios shown in Table 4 so that the total amount was 6.5 mol. Further, 1.03 times the molar amount of acetic anhydride based on the total amount of hydroxyl groups (mol) of all monomers was charged, and deacetic acid polymerization was carried out under the following conditions.

[0116] [Table 4]

[0117] The temperature was raised from room temperature to 150 °C in 1 hour under a nitrogen gas atmosphere and held at the same temperature for 30 minutes. Next, while distilling off the by-produced acetic acid, the temperature was raised to 350 °C over 7 hours, and then the pressure was reduced to 5 mmHg over 80 minutes. When a predetermined torque was shown, the polymerization reaction was terminated, the content of the reaction vessel was taken out, and Liquid crystal polymer pellets were obtained by a pulverizer. The amount of acetic acid distilled off during polymerization was almost the same as the theoretical value. The crystal melting temperature (Tm) of the obtained pellets was 332 °C.

[0118] Synthesis Example 3 (LCP3) Into a reaction vessel equipped with a stirring device with a torque meter and a distillation tube, POB, BON6, HQ, and NDA were charged at the composition ratios shown in Table 5 so that the total amount was 6.5 mol. Further, 1.03 times the molar amount of acetic anhydride based on the amount of hydroxyl groups (mol) of all monomers was charged, and deacetic acid polymerization was carried out under the following conditions.

[0119]

Table 5

[0120] The temperature was raised from room temperature to 150 °C in 1 hour under a nitrogen gas atmosphere and held at the same temperature for 30 minutes. Next, while distilling off the by-produced acetic acid, the temperature was raised to 350 °C over 7 hours, and then the pressure was reduced to 5 mmHg over 80 minutes. When a predetermined torque was shown, the polymerization reaction was terminated, the content of the reaction vessel was taken out, and Liquid crystal polymer pellets were obtained by a pulverizer. The amount of acetic acid distilled off during polymerization was almost the same as the theoretical value. The crystal melting temperature (Tm) of the obtained pellets was 321 °C.

[0121] Hereinafter, the talc and glass fiber used in Examples and Comparative Examples are shown. Talc 1: Manufactured by Nippon Talc Co., Ltd., talc "MS-SF" (average particle diameter: 16 μm, quartz content: 0.02%) Talc 2: Manufactured by Tamura Talc Kogyosho Co., Ltd., talc "TP-40B" (average particle diameter: 16 μm, quartz content: 0.00%) Talc 3: Manufactured by Fuji Talc Industry Co., Ltd., talc "NK-64" (average particle size: 17 μm, quartz content: 0.28%) Talc 4: Manufactured by Fuji Talc Industry Co., Ltd., talc "DS-34" (average particle size: 13 μm, quartz content: 0.80%) Glass fiber: Manufactured by CPIC, ECS3010A (number average fiber diameter 10.5 μm, number average fiber length 3 mm, quartz content: 0.00%)

[0122] Examples 1 to 5 and Comparative Examples 1 to 4 The synthesized LCP and the above talc and glass fiber were blended so as to have the contents (parts by mass) shown in Table 6, and melt kneading was carried out at a cylinder temperature of 350 °C using a twin-screw extruder (TEX-30 manufactured by Nippon Steel Corporation) to obtain pellets of the liquid crystal polymer composition. Thereafter, by the above method, the tensile strength, tensile elongation at break, Izod impact strength, heat distortion temperature under load, melt viscosity, 0.1 mm thickness flow length, and step blister were measured and evaluated. The results are shown in Table 6.

[0123] As shown in Table 6, all of the liquid crystal polymer compositions of Examples 1 to 5 were excellent in blister resistance while maintaining the mechanical strength and heat resistance of the liquid crystal polymer at a certain level.

[0124] On the other hand, the liquid crystal polymer compositions of Comparative Examples 1 to 4 were inferior in blister resistance.

[0125] Comparing Examples 1 to 2 with Comparative Examples 1 to 2, Example 4 with Comparative Example 3, and Example 5 with Comparative Example 4, in each case, when talc with a low quartz content was used, the 0.1 mm thickness flow length tended to be excellent, and it was understood that the thin-wall fluidity was improved.

Table 6

Claims

1. A liquid crystal polymer composition comprising 5 to 100 parts by mass of talc having a quartz content of 0 to 0.15% by mass and 0.1 to 100 parts by mass of glass fiber, based on 100 parts by mass of a liquid crystal polymer, The liquid crystal polymer is represented by the formula (I) and / or the formula (II): 【Chemistry 1】 and further comprising a repeating unit represented by formula (III) and formula (IV): 【Chemistry 2】 [In the formula, Ar 1 and Ar 2 each independently represent a divalent aromatic group.] A liquid crystal polymer composition comprising a repeating unit represented by the formula:

2. The repeating units represented by formulae (III) to (IV) are Ar １ and Ar ２ are each independently represented by the formulas (1) to (4). 【Chemistry 3】 2. The liquid crystal polymer composition according to claim 1, wherein each repeating unit is one or more types selected from aromatic groups represented by the following formula:

3. The liquid crystal polymer is represented by the formula (I) and the formula (II): 【Chemistry 4】 The liquid crystalline polymer composition according to claim 1 , comprising a repeating unit represented by:

4. The repeating units represented by formulae (III) to (IV) are Ar １ and Ar ２ are each independently represented by the formulas (1) to (4). 【Chemistry 5】 The liquid crystal polymer composition according to claim 3, wherein each repeating unit is one or more kinds of repeating units selected from aromatic groups represented by the following formula:

5. 2. The liquid crystal polymer composition according to claim 1, wherein the liquid crystal polymer has a crystalline melting temperature of 290 to 360° C. as measured by a differential scanning calorimeter.

6. 2. The liquid crystal polymer composition according to claim 1, wherein the average particle size of the talc is 0.1 to 100 μm.

7. 2. The liquid crystal polymer composition according to claim 1, wherein the content of quartz in the liquid crystal polymer composition is 0 to 0.040% by mass.

8. A molded article made from the liquid crystal polymer composition according to any one of claims 1 to 7.

9. The molded article according to claim 8, which is a part constituting one selected from the group consisting of a connector, a switch, a relay, a bobbin, a capacitor, a coil, a motor, a fan, a test socket, a transformer, a camera module, and an antenna.

Images