Liquid crystalline resin composition and film using same

Abstract

The present invention provides: a liquid crystalline resin composition which is capable of providing a film that has excellent dielectric characteristics, film forming properties, and mechanical strength in a well-balanced manner; and a film using the same.　A liquid crystalline resin pellet according to the present invention contains (A) a liquid crystalline resin and (B) an amorphous polyarylate. The liquid crystalline resin (A) contains the following constituent units (I) and (II) as essential constituent components, and with respect to all constituent units in the liquid crystalline resin (A), the content of the constituent unit (I) is 60-85 mol% and the content of the constituent unit (II) is 12-40 mol%. With respect to the entire liquid crystalline resin composition, the content of the liquid crystalline resin (A) is 95.5-99.9 mass% and the content of the amorphous polyarylate (B) is 0.1-4.5 mass%.

Description

Liquid crystal resin composition and film using the same

[0001] The present invention relates to a liquid crystalline resin composition and a film using the same.

[0002] Liquid crystalline resins have a good balance of excellent mechanical strength, heat resistance, chemical resistance, electrical properties, etc., and also have excellent dimensional stability, and therefore are widely used as high-performance engineering plastics. In addition, melt-extruded films made of liquid crystalline resins are also produced by melt extrusion methods such as the T-die method and the inflation method (see, for example, Patent Documents 1 and 2).

[0003] Meanwhile, in recent years, remarkable technological developments have been made in the field of information and communications, including mobile phones; wireless LANs; and ITS technologies such as GPS, VICS (registered trademark), and ETC. Accordingly, there is a growing need for high-performance electronic components that can be used in high-frequency ranges, such as microwaves and millimeter waves. Materials constituting such electronic components are required to have appropriate dielectric properties depending on the design of each electronic component. For example, Patent Document 3 discloses that a wholly aromatic polyester resin containing structural units derived from 2,3,5-trimethylhydroquinone has good dielectric properties in the high-frequency band.

[0004] Japanese Patent Application Laid-Open No. 05-043664 Japanese Patent Application Laid-Open No. 63-168327 Japanese Patent Application Laid-Open No. 2021-187872

[0005] According to the investigations of the present inventors, it has been found that melt-extruded films containing a large amount of conventional liquid crystalline resins with excellent dielectric properties are prone to develop holes when produced by the T-die method or the inflation method, and that improvements in film formability are required. In addition, it has been found that after production, the mechanical strength tends to be low and the films are brittle. The present invention has been made to solve the above problems, and an object of the present invention is to provide a liquid crystalline resin composition and a film using the same that can give films with a good balance of excellent dielectric properties, film formability, and mechanical strength.

[0006] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, they have found that the above-mentioned problems can be solved by using a liquid crystalline resin composition containing a liquid crystalline resin containing specific structural units in a specific ratio and an amorphous polyarylate in a specific ratio, and have completed the present invention. More specifically, the present invention provides the following.

[0007] (1) A liquid crystalline resin composition containing (A) a liquid crystalline resin, and (B) an amorphous polyarylate, wherein the (A) liquid crystalline resin contains the following structural units (I) and (II) as essential structural components, and the content of the structural unit (I) is 60 to 85 mol % and the content of the structural unit (II) is 12 to 40 mol % relative to all structural units in the (A) liquid crystalline resin, and the content of the (A) liquid crystalline resin is 95.5 to 99.9 mass % and the content of the (B) amorphous polyarylate is 0.1 to 4.5 mass % relative to the entire liquid crystalline resin composition.

[0008] (2) The liquid crystal resin composition according to (1), wherein the total content of the structural units (I) and (II) is 97 to 100 mol % based on all structural units in the liquid crystal resin (A).

[0009] (3) The liquid crystal resin composition according to (1) or (2), wherein the amorphous polyarylate (B) is a poly(4,4'-isopropylidenediphenylene terephthalate) / isophthalate copolymer.

[0010] (4) Temperature: 340°C and shear rate: 1000 sec －１ The liquid crystal resin composition according to any one of (1) to (3), wherein the melt viscosity of the amorphous polyarylate (B) is 800 to 1300 Pa·s.

[0011] (5) The liquid crystalline resin composition according to any one of (1) to (4), which is for use in a film.

[0012] (6) Use of the liquid crystal resin composition according to any one of (1) to (5) for producing a film.

[0013] (7) A film comprising the liquid crystal resin composition according to any one of (1) to (5).

[0014] According to the present invention, it is possible to provide a liquid crystalline resin composition capable of giving a film having a good balance of dielectric properties, film formability, and mechanical strength, and a film using the same.

[0015] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0016] <Liquid Crystalline Resin Composition> The liquid crystal resin composition of the present invention contains (A) a liquid crystal resin and (B) an amorphous polyarylate.

[0017] [(A) Liquid Crystalline Resin] The liquid crystal resin composition according to the present invention contains (A) liquid crystal resin. The (A) liquid crystal resin may be used singly or in combination of two or more. The (A) liquid crystal resin contains the following structural units (I) and (II) as essential components, with the content of structural unit (I) being 60 to 85 mol % and the content of structural unit (II) being 12 to 40 mol % relative to all structural units in the (A) liquid crystal resin.

[0018]

[0019] The structural unit (I) is derived from, for example, 6-hydroxy-2-naphthoic acid (hereinafter also referred to as "HNA"). Hereinafter, a monomer from which the structural unit (I) is derived, such as HNA, will also be referred to as monomer (I). The component (A) contains 60 to 85 mol% of the structural unit (I) relative to all structural units. When the content of the structural unit (I) is within this range, the dielectric dissipation factor is likely to be reduced. From the perspective of reducing the dielectric dissipation factor, the content of the structural unit (I) is preferably 65 to 82 mol%, more preferably 75 to 80 mol%, relative to all structural units in the liquid crystal resin (A).

[0020] The structural unit (II) is derived from, for example, 4-hydroxybenzoic acid (hereinafter also referred to as "HBA"). Hereinafter, a monomer from which the structural unit (II) is derived, such as HBA, will also be referred to as monomer (II). The component (A) contains 12 to 40 mol% of the structural unit (II) relative to all structural units. When the content of the structural unit (II) is within this range, the dielectric dissipation factor is likely to be reduced. From the perspective of reducing the dielectric dissipation factor, the content of the structural unit (II) is preferably 16 to 35 mol%, more preferably 19 to 25 mol%, relative to all structural units in the liquid crystal resin (A).

[0021] Since the component (A) contains the specific structural units (I) and (II) in specific amounts relative to the total structural units, it is easy to obtain a film with sufficient mechanical strength. In the (A) liquid-crystalline resin, from the viewpoint of maintaining mechanical strength, the total content of the structural units (I) and (II) relative to the total structural units in the (A) liquid-crystalline resin is preferably 97 to 100 mol%, more preferably 98 to 100 mol%, even more preferably 99 to 100 mol%, and particularly preferably 99.15 to 100 mol%. In other embodiments, the total content of the structural units (I) and (II) relative to the total structural units in the (A) liquid-crystalline resin may be in the range of 97 to 99.9 mol%, 98 to 99.8 mol%, or 98.5 to 99.7 mol%. Therefore, the liquid-crystalline resin of the present invention may contain a structural unit other than the structural units (I) and (II) (hereinafter also referred to as "structural unit (Z)") in order to impart desired properties according to its purpose. As long as the effect of maintaining mechanical strength is not impaired, the content of the structural unit (Z) is preferably 0 to 3 mol%, more preferably 0 to 2 mol%, even more preferably 0 to 1 mol%, and particularly preferably 0 to 0.85 mol%, relative to all structural units in the (A) liquid crystal resin. In other embodiments, the content of the structural unit (Z) may be in the range of 0.1 to 3 mol%, 0.2 to 2 mol%, or 0.3 to 1.5 mol%, relative to all structural units in the (A) liquid crystal resin. In summary, the (A) liquid crystal resin contains the above-mentioned structural units (I) and (II) as essential components, and may or may not contain the structural unit (Z), and the content of the structural unit (I) is 60 to 85 mol%, the content of the structural unit (II) is 12 to 40 mol%, and the content of the structural unit (Z) is 0 to 3 mol%, relative to all structural units in the (A) liquid crystal resin.

[0022] The structural unit (Z) is not particularly limited, and examples thereof include structural units derived from at least one selected from the group consisting of 1,2-phenylenedicarboxylic acid, 1,3-phenylenedicarboxylic acid (hereinafter also referred to as "IA"), 1,4-phenylenedicarboxylic acid (hereinafter also referred to as "TA"), 2,6-naphthalenedicarboxylic acid (hereinafter also referred to as "NDA"), hydroquinone (hereinafter also referred to as "HQ"), 2,6-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl (hereinafter also referred to as "BP"), N-acetyl-p-aminophenol (hereinafter also referred to as "APAP"), aliphatic chain dicarboxylic acids, alicyclic dicarboxylic acids, aliphatic chain diols, alicyclic diols, and derivatives thereof. From the viewpoint of reducing the dielectric loss tangent, structural units derived from at least one selected from the group consisting of TA, BP, and derivatives thereof are preferred, and structural units derived from at least one selected from the group consisting of TA and derivatives thereof are more preferred. Hereinafter, the monomer that derives the structural unit (Z) is also referred to as the monomer (Z). In the (A) liquid crystal resin, the structural unit (Z) may be used alone, or two or more types may be used in combination.

[0023] Next, a method for producing the liquid crystalline resin of the present invention will be described. The liquid crystalline resin of the present invention is polymerized using a direct polymerization method, an ester exchange method, etc. For the polymerization, a melt polymerization method, a solution polymerization method, a slurry polymerization method, a solid phase polymerization method, etc., or a combination of two or more of these methods is used, and a melt polymerization method or a combination of a melt polymerization method and a solid phase polymerization method is preferably used.

[0024] In the present invention, an acylating agent for the polymerizable monomer or a monomer having an activated terminal as an acid chloride derivative can be used in the polymerization. Examples of the acylating agent include fatty acid anhydrides such as acetic anhydride.

[0025] Various catalysts can be used in these polymerizations, and examples thereof include metal salt catalysts such as fatty acid metal salt catalysts and organic compound catalysts. Typical examples include metal salt catalysts such as potassium acetate, magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, antimony trioxide, and tris(2,4-pentanedionato)cobalt(III), and organic compound catalysts such as 1-methylimidazole and 4-dimethylaminopyridine.

[0026] The reaction conditions are, for example, a reaction temperature of 200 to 380°C and a final pressure of 0.1 to 760 Torr (i.e., 13 to 101,080 Pa). In particular, in the case of a melting reaction, the reaction temperature is, for example, 260 to 380°C, preferably 300 to 360°C, and the final pressure is, for example, 1 to 100 Torr (i.e., 133 to 13,300 Pa), preferably 1 to 50 Torr (i.e., 133 to 6,670 Pa).

[0027] The reaction can be initiated by charging all raw material monomers (monomer (I), monomer (II), and optionally monomer (Z)), an acylating agent, and a catalyst into the same reaction vessel (single-stage system), or by acylating the hydroxyl groups of monomer (I), monomer (II), and optionally monomer (Z) having a hydroxyl group with an acylating agent, followed by reacting with the carboxyl groups of monomer (I), monomer (II), and optionally monomer (Z) having a carboxyl group (two-stage system).

[0028] The melt polymerization is carried out by starting pressure reduction and setting the pressure to a predetermined level after the reaction system has reached a predetermined temperature. After the torque of the stirrer has reached a predetermined value, an inert gas is introduced, and the pressure is increased from a reduced pressure state to normal pressure and then to a predetermined pressurized state, and the liquid crystalline resin is discharged from the reaction system.

[0029] The liquid crystalline resin produced by the above polymerization method can be further subjected to solid-state polymerization by heating in an inert gas at normal or reduced pressure to increase the molecular weight. Preferred conditions for the solid-state polymerization reaction are a reaction temperature of 230 to 350°C, preferably 260 to 330°C, and a final pressure of 10 to 760 Torr (i.e., 1,330 to 101,080 Pa).

[0030] Next, the properties of the liquid crystalline resin will be described. The liquid crystalline resin of the present invention exhibits optical anisotropy when melted. When a resin exhibits optical anisotropy when melted, it means that the resin is a liquid crystalline resin. The liquid crystalline resin of the present invention has both thermal stability and easy processability.

[0031] The melt anisotropy can be confirmed by a conventional polarization inspection method using crossed polarizers. More specifically, melt anisotropy can be confirmed by melting a sample placed on a Linkam hot stage using an Olympus polarizing microscope and observing it at 150x magnification under a nitrogen atmosphere. Liquid crystal resins are optically anisotropic and transmit light when inserted between crossed polarizers. If a sample is optically anisotropic, polarized light will transmit even when it is in a molten, static liquid state, for example.

[0032] Nematic liquid crystalline resins experience a significant drop in viscosity above their melting point, and therefore, the fact that they exhibit liquid crystallinity at or above their melting point is generally an indicator of processability. While a melting point as high as possible is preferable from the standpoint of heat resistance, taking into account factors such as thermal degradation during melt processing of the liquid crystalline resin and the heating capacity of the extruder, a melting point of 380°C or less is a preferable guideline. A melting point of 250 to 380°C is more preferable, and a melting point of 300 to 360°C is even more preferable.

[0033] A temperature 10 to 30°C higher than the melting point of the liquid crystal resin and a shear rate of 1000 sec －１ The melt viscosity of the liquid crystalline resin in the above range is preferably 300 Pa·s or less, more preferably 5 to 150 Pa·s, and even more preferably 10 to 100 Pa·s. When the melt viscosity is within the above range, the liquid crystalline resin itself or a composition containing the liquid crystalline resin is likely to ensure film formability during extrusion. In this specification, the melt viscosity is measured in accordance with ISO 11443.

[0034] The content of the liquid crystalline resin (A) relative to the total mass of the liquid crystalline resin composition of the present invention is 95.5 to 99.9 mass%, preferably 96.0 to 98.5 mass%, and more preferably 96.5 to 97.5 mass%. The content of the component (A) within the above range is preferred from the viewpoint of the balance of dielectric properties, film formability, and mechanical strength.

[0035] [(B) Amorphous Polyarylate] The liquid crystalline resin composition according to the present invention contains (B) amorphous polyarylate. By containing (B) amorphous polyarylate in the liquid crystalline resin composition according to the present invention, a film having excellent film formability and mechanical strength can be easily obtained. The (B) amorphous polyarylate can be used alone or in combination of two or more.

[0036] The amorphous polyarylate (B) is not particularly limited, and examples thereof include wholly aromatic polyesters which are condensation products of dihydric phenol compounds and aromatic dicarboxylic acids, and specific examples thereof include poly(4,4'-isopropylidenediphenylene terephthalate / isophthalate copolymers).

[0037] Temperature: 340°C and shear rate: 1000 sec －１ The melt viscosity of the amorphous polyarylate (B) in the above is 800 to 1300 Pa s, and is preferably 850 to 1250 Pa s, more preferably 900 to 1220 Pa s, and even more preferably 940 to 1200 Pa s, because a film having an even better balance of dielectric properties, film formability, and mechanical strength can be easily obtained. In this specification, the melt viscosity is measured in accordance with ISO 11443.

[0038] The content of the amorphous polyarylate (B) relative to the total amount of the liquid crystal resin composition of the present invention is 0.1 to 4.5% by mass. When the content of the amorphous polyarylate (B) is within the above range, a film having an excellent balance of dielectric properties, film formability, and mechanical strength can be easily obtained from the resulting composition. The content of the amorphous polyarylate (B) is preferably 1.5 to 4.0% by mass, more preferably 2.5 to 3.5% by mass.

[0039] [Other Components] To the liquid crystalline resin composition of the present invention, other polymers, fillers (particulate fillers such as silica; plate-like fillers such as talc and mica; fibrous fillers such as glass fiber; carbon black, etc.), known substances generally added to synthetic resins, i.e., stabilizers such as antioxidants and ultraviolet absorbers, antistatic agents, flame retardants, colorants such as dyes and pigments, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents, etc. may be added as appropriate depending on the required performance, within a range that does not impair the effects of the present invention.

[0040] Examples of other polymers include epoxy group-containing styrene polymers and non-epoxy group-containing olefin polymers. Examples of epoxy group-containing styrene polymers include known epoxy group-containing styrene polymers, including copolymers composed of repeating units derived from styrenes and repeating units derived from glycidyl esters of α,β-unsaturated acids. Examples of epoxy group-free olefin polymers include polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, polybutadiene, polyisoprene, polychloroprene, ethylene-propylene-butadiene copolymer, ethylene-propylene-isoprene copolymer, ethylene-propylene-chloroprene copolymer, ethylene-ethyl acrylate copolymer, and ethylene-vinyl acetate copolymer.

[0041] [Preparation of Liquid Crystalline Resin Composition] The preparation of the resin composition of the present invention is not particularly limited. For example, the liquid crystal resin composition is prepared by blending the above-mentioned components (A), (B), and optionally other components, and melt-kneading them using a single-screw or twin-screw extruder.

[0042] [Liquid Crystalline Resin Composition] From the viewpoint of fluidity, the melt viscosity of the liquid crystal resin composition of the present invention obtained as described above is preferably 100 Pa·s or less, more preferably 90 Pa·s or less, and even more preferably 85 Pa·s or less. The lower limit of the melt viscosity is not particularly limited, and may be 5 Pa·s or more, 10 Pa·s or more, or 20 Pa·s or more. One of the features of the liquid crystal resin composition of the present invention is that it has high fluidity when melted and excellent moldability. In this specification, the melt viscosity is defined as the viscosity at a cylinder temperature 10 to 30°C higher than the melting point of the liquid crystal resin, a shear rate of 1000 sec －１ The value obtained by the measurement method in accordance with ISO 11443 under the above conditions is adopted.

[0043] <Film> The liquid crystalline resin composition can be used for a film. More specifically, the liquid crystalline resin composition can be used to produce a film. That is, a film can be produced using the liquid crystalline resin composition. The film according to the present invention contains the liquid crystalline resin composition according to the present invention. The film according to the present invention is not particularly limited, and examples thereof include melt-extruded films.

[0044] The film according to the present invention is not particularly limited in its application, and can be used in a variety of fields, for example, as an industrial film such as an insulating film, a waterproof film, or a heat-resistant film, or as a film for packaging materials such as a gas barrier film.

[0045] In the film according to the present invention, the number of times the film can be bent until it breaks (folding endurance) in the MIT test in accordance with JIS P 8115 is preferably 1,100 or more, more preferably 1,300 or more, even more preferably 1,500 or more, and particularly preferably 1,800 or more.

[0046] The film according to the present invention has a dielectric loss tangent at a measurement frequency of 5 GHz of preferably 0.0011 or less, more preferably 0.0010 or less, and even more preferably 0.0009 or less. A low dielectric loss tangent is also one of the features of the film according to the present invention.

[0047] [Film manufacturing method] The film of the present invention can be produced as a melt-extruded film by, for example, melting a liquid crystalline resin composition in a single-screw extruder, discharging the molten resin composition from the extruder and feeding it into a die, extruding the molten resin composition from the die into a sheet, and cooling and solidifying it. The liquid crystalline resin composition melted in the extruder is discharged from the die into a sheet, and is cast, for example, on a rotating cooling drum and rapidly cooled and solidified to obtain a melt-extruded film. After cooling and solidifying, this melt-extruded film may be subjected to longitudinal stretching and transverse stretching in that order, as appropriate, and may finally be wound into a roll.

[0048] The extruder is a single-screw type extruder equipped with a single screw in a cylinder. The cylinder has a supply port through which the liquid crystalline resin composition is supplied into the cylinder. The cylinder is composed of, in order from the supply port side, a supply section that transports a fixed amount of the liquid crystalline resin composition supplied from the supply port, a compression section that kneads and compresses the liquid crystalline resin composition, and a transport and metering section that transports the kneaded and compressed liquid crystalline resin composition to a discharge port while metering the discharge amount.

[0049] The screw compression ratio of the extruder is set, for example, to 2.5 to 5.0, and L / D is set, for example, to 18 to 45. Here, the screw compression ratio refers to the degree to which the liquid crystalline resin composition is compressed in a molten state in order to knead it under back pressure, and is expressed as the volume ratio between the supply section and the conveying and metering section (i.e., volume per unit length of the supply section / volume per unit length of the conveying and metering section), and is calculated using the outer diameter d1 of the screw shaft of the supply section, the outer diameter d2 of the screw shaft of the conveying and metering section, the groove diameter a1 of the supply section, and the groove diameter a2 of the conveying and metering section. Furthermore, L / D is the ratio of the cylinder length (L) to the cylinder inner diameter (D).

[0050] When the screw compression ratio is 2.5 or more, the composition is sufficiently kneaded, and undissolved portions are unlikely to occur, and shear heat generation is small, resulting in insufficient melting of the crystals. Conversely, when the screw compression ratio is 5.0 or less, excessive shear stress is not applied, and the liquid crystal resin composition is unlikely to deteriorate due to heat generation, or the molecular weight is unlikely to decrease due to scission of the liquid crystal resin molecules. This makes it difficult for the molten resin composition to become non-uniform. The screw compression ratio is preferably in the range of 2.6 to 4.0, more preferably in the range of 2.7 to 3.5, and particularly preferably in the range of 2.8 to 3.0.

[0051] When L / D is 18 or more, insufficient melting or kneading is unlikely to occur, and fine crystals are unlikely to remain, as in the case where the screw compression ratio is 2.5 or more. Conversely, when L / D is 45 or less, the residence time of the liquid crystalline resin in the extruder is unlikely to be long, and the resin is unlikely to deteriorate. Furthermore, when the residence time is unlikely to be long, scission of the liquid crystalline resin molecules is unlikely to occur, and the molecular weight is unlikely to decrease. L / D is preferably in the range of 21 to 40, preferably in the range of 25 to 35, and particularly preferably in the range of 28 to 30.

[0052] The liquid crystalline resin composition is melted by the extruder configured as described above, and the molten resin composition is continuously fed from the discharge port to the die. The molten resin composition fed to the die by the extruder is then extruded into a sheet form from the die, and is then cast, for example, onto a cooling drum and cooled and solidified to form a melt-extruded film. Here, the melting point Tm (°C) of the liquid crystalline resin composition and the set temperature Td (°C) of the die preferably satisfy the relationship Tm - 10 ≦ Td ≦ Tm + 15. When Tm - 10 ≦ Td ≦ Tm + 15, the set temperature of the die is neither too low nor too high, and holes are less likely to form in the melt-extruded film. Tm (°C) and Td (°C) preferably satisfy the relationship Tm - 9 ≦ Td ≦ Tm + 14, more preferably Tm - 8 ≦ Td ≦ Tm + 13.

[0053] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0054] <Liquid Crystalline Resins> Liquid Crystalline Resin 1 After the following raw materials were charged into a polymerization vessel, the temperature of the reaction system was raised to 140°C and allowed to react at 140°C for 2 hours. The temperature was then further raised to 340°C over 4.1 hours, and the pressure was then reduced to 10 Torr (i.e., 1330 Pa) over 15 minutes, and melt condensation was carried out while distilling off acetic acid, excess acetic anhydride, and other low-boiling components. After the stirring torque reached a predetermined value, nitrogen was introduced to change the pressure from a reduced pressure state to normal pressure and then to a pressurized state, and the polymer was discharged from the bottom of the polymerization vessel and pelletized by a strand cut method to obtain the target polymer as pellets. The melting point of the obtained polymer was 322°C, and the melt viscosity at 340°C was 33 Pa·s. 6-Hydroxy-2-naphthoic acid (HNA): 1985 g (76 mol%), 4-hydroxybenzoic acid (HBA): 447 g (23.3 mol%), 1,4-phenylenedicarboxylic acid (TA): 16 g (0.7 mol%), fatty acid metal salt catalyst (potassium acetate catalyst): 22.5 mg, acylating agent (acetic anhydride): 1435 g

[0055] Liquid Crystalline Resin 2: After the following raw materials were charged into a polymerization vessel, the temperature of the reaction system was raised to 140°C and allowed to react at 140°C for 1 hour. The temperature was then further raised to 325°C over 3.5 hours, and the pressure was then reduced to 5 Torr (i.e., 667 Pa) over 20 minutes. Melt polymerization was carried out while distilling off acetic acid, excess acetic anhydride, and other low-boiling components. After the stirring torque reached a predetermined value, nitrogen was introduced to change the pressure from reduced pressure to normal pressure and then to pressurized pressure. The polymer was discharged from the bottom of the polymerization vessel and pelletized by a strand cut method to obtain the target polymer as pellets. The melting point of the resulting pellets was 282°C, and the melt viscosity at 300°C was 44 Pa·s. 6-Hydroxy-2-naphthoic acid (HNA): 837 g (27 mol%); 4-hydroxybenzoic acid (HBA): 1,660 g (73 mol%); fatty acid metal salt catalyst (potassium acetate catalyst): 165 mg; acylating agent (acetic anhydride): 1,714 g

[0056] Liquid Crystalline Resins 3 to 8 Liquid crystal resins were obtained in the same manner as Liquid Crystalline Resin 1, except that the types of raw material monomers and the charging ratios (mol%) were as shown in Table 1 or Table 2. The melting points of the liquid crystal resins are as follows: Liquid Crystalline Resin 3: 337°C Liquid Crystalline Resin 4: 312°C Liquid Crystalline Resin 5: 328°C Liquid Crystalline Resin 6: 325°C Liquid Crystalline Resin 7: 322°C Liquid Crystalline Resin 8: 322°C

[0057] <Melting Point> Using a differential scanning calorimeter (DSC, manufactured by Hitachi High-Tech Science Corporation), the obtained liquid crystalline resin pellets were heated from room temperature at a heating rate of 20°C / min, and the endothermic peak temperature (Tm1) observed when heated was measured. Then, the pellets were held at a temperature of (Tm1 + 40)°C for 2 minutes. After further cooling to room temperature at a heating rate of 20°C / min, the pellets were heated again at a heating rate of 20°C / min, and the endothermic peak temperature (Tm2) observed when heated was measured as the melting point.

[0058] <Melt Viscosity> Using a Capillograph 1B model manufactured by Toyo Seiki Seisakusho, Ltd., the melt viscosity was measured at the following temperature using an orifice with an inner diameter of 1 mm and a length of 20 mm at a shear rate of 1000 sec. －１ The melt viscosity of the liquid crystal resins was measured in accordance with ISO 11443 at the following temperatures: Liquid crystal resin 1: 340°C Liquid crystal resin 2: 300°C

[0059] <Amorphous Polyarylate> PAR1: U Powder R Type (manufactured by Unitika Ltd., polyarylate resin represented by the formula below, melt viscosity at 340°C: 940 Pa·s) PAR2: U Polymer U-100 (manufactured by Unitika Ltd., polyarylate resin represented by the formula below, melt viscosity at 340°C: 1080 Pa·s) PAR3: U Powder S Type (manufactured by Unitika Ltd., polyarylate resin represented by the formula below, melt viscosity at 340°C: 1200 Pa·s)

[0060] The polyarylate resin represented by the above formula is a poly(4,4'-isopropylidenediphenylene terephthalate / isophthalate) copolymer, where n represents the number of structural units to which n is added, and specifically, is a number such that the melt viscosity of the polyarylate resin represented by the above formula is the value described above.

[0061] <Production of Liquid Crystalline Resin Composition> The above components were melt-kneaded in the proportions shown in Table 1 or Table 2 using a twin-screw extruder (TEX30α type, manufactured by The Japan Steel Works, Ltd.) at the following cylinder temperatures to obtain liquid crystal resin composition pellets. [Production conditions] Cylinder temperature: 340°C (Examples 1 to 3, 6 to 9, and Comparative Examples 1 to 4) 300°C (Reference Example 1) 350°C (Example 4) 330°C (Example 5)

[0062] <Melt Viscosity> Using a Capillograph 1B model manufactured by Toyo Seiki Seisakusho Co., Ltd., the melt viscosity was measured at a temperature 10 to 30°C higher than the melting point of the liquid crystalline resin, using an orifice with an inner diameter of 1 mm and a length of 20 mm, at a shear rate of 1000 sec. －１ The melt viscosity of the liquid crystalline resin composition was measured in accordance with ISO 11443 at 340°C. The specific measurement temperatures were as follows. The results are shown in Tables 1 and 2. Measurement temperature: 340°C (Examples 1 to 3, 6 to 9, and Comparative Examples 1 to 4) 300°C (Reference Example 1) 350°C (Example 4) 330°C (Example 5)

[0063] <Melt Tension> The melt tension of the liquid crystalline resin composition was measured using a Capillograph 1B (piston diameter 10 mm) manufactured by Toyo Seiki Seisakusho, Ltd., using an orifice with an inner diameter of 1 mm and a length of 20 mm. The liquid crystalline resin composition was discharged from the orifice under the following conditions: measurement temperature, extrusion speed of 30 mm / min, and discharge speed of 2.74 m / min. The liquid crystalline resin composition was taken up in a fibrous form at a take-up speed of 150 m / min, and the tension (mN) applied to the fiber was measured, and this was taken as the melt tension of the liquid crystalline resin composition. The results are shown in Tables 1 and 2. Measurement temperature: 340°C (Examples 1 to 3, 6 to 9, and Comparative Examples 1 to 4) 300°C (Reference Example 1) 350°C (Example 4) 330°C (Example 5)

[0064] <Production of Melt-Extruded Film> The obtained liquid crystalline resin pellets were used as a raw material and melted under the following conditions in a single-screw extruder (20 mmφ single-screw extruder "Laboplastomill" manufactured by Toyo Seiki Seisakusho, Ltd.) with a screw compression ratio of 2.9 and L / D = 29, and the melt was extruded into a film form from a T-die (coat hanger die with a width of 150 mm) at the tip of the extruder, with the die temperature set to film-forming temperature 1 or film-forming temperature 2 shown in Table 1 or Table 2, and cooled. The take-up speed was adjusted to produce a melt-extruded film with a thickness of 100 μm. Cylinder temperature: same as the die temperature setting Screw rotation speed: 35 rpm Discharge rate: 30 kg / h

[0065] <Film-forming ability> The state of holes in the melt-extruded film produced at film-forming temperature 1 as described above was visually inspected, and the film-forming ability was evaluated according to the following criteria. The results are shown in Tables 1 and 2. ∘ (Good): No holes were observed in the melt-extruded film. × (Poor): Holes were observed in the melt-extruded film.

[0066] <Mechanical Strength> The melt-extruded film produced at film-forming temperature 2 was cut into a predetermined size (100 mm x 15 mm x 100 μmt) and subjected to an MIT test in accordance with JIS P 8115 using an MIT folding fatigue tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.). As an index of the mechanical strength of the melt-extruded film, the number of times the film could be bent until it broke (folding endurance number) was measured. The results are shown in Tables 1 and 2.

[0067] <Dielectric Properties> The dielectric loss tangent at 5 GHz of the melt-extruded film produced at film-forming temperature 2 was measured using a cavity resonator perturbation method complex dielectric constant evaluation device manufactured by Kanto Electronics Application Development Co., Ltd., having the following configuration. The results are shown in Tables 1 and 2. Scalar network analyzer: Agilent Technology 8757D Frequency synthesizer: Agilent Technology 83650L sweep CW generator Fixed attenuator: Agilent Technology 85025D detector Cavity resonator: Kanto Electronics Application Development CP431 Measurement program: Kanto Electronics Application Development CPMA-S2 / V2

[0068]

[0069]

[0070] As is clear from the results shown in Tables 1 and 2, it was confirmed that the liquid crystalline resin compositions of the examples can give films that are well-balanced and excellent in dielectric properties, film-forming properties, and mechanical strength.

Claims

1. A liquid crystalline resin composition containing (A) a liquid crystalline resin, and (B) an amorphous polyarylate, wherein the (A) liquid crystalline resin contains the following structural units (I) and (II) as essential structural components, and the content of structural unit (I) is 60 to 85 mol % and the content of structural unit (II) is 12 to 40 mol % relative to all structural units in the (A) liquid crystalline resin, and the content of the (A) liquid crystalline resin is 95.5 to 99.9 mass % and the content of the (B) amorphous polyarylate is 0.1 to 4.5 mass % relative to the entire liquid crystalline resin composition.

2. The liquid crystal resin composition according to claim 1, wherein the total content of the structural units (I) and (II) is 97 to 100 mol % based on all structural units in the liquid crystal resin (A).

3. The liquid crystal resin composition according to claim 1 or 2, wherein the amorphous polyarylate (B) is a poly(4,4'-isopropylidenediphenylene terephthalate) / isophthalate copolymer.

4. Temperature: 340°C and shear rate: 1000 sec －１ 3. The liquid crystal resin composition according to claim 1, wherein the amorphous polyarylate (B) has a melt viscosity of 800 to 1300 Pa·s.

5. The liquid crystalline resin composition according to claim 1 or 2, which is for use in a film.

6. Use of the liquid crystalline resin composition according to claim 1 or 2 for producing a film.

7. A film comprising the liquid crystalline resin composition according to claim 1 or 2.

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