Liquid crystal resin composition, metal-liquid crystal resin composite using the same, and method for producing the same.

Abstract

To provide a liquid crystalline resin composition which is excellent in bond strength to a metal member, a metal-liquid crystalline resin composite body using the same, and a manufacturing method of the same.SOLUTION: A liquid crystalline resin composition is used in insert molding, wherein the liquid crystalline resin composition contains a liquid crystalline resin and an inorganic filler, and a loss coefficient in a crystallization temperature (Tc) of the liquid crystalline resin composition is 0.20 or more.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a liquid crystalline resin composition, a metal-liquid crystalline resin composite using the same, and a method for producing the same.

Background Art

[0002] Liquid crystalline resins typified by aromatic polyester resins and aromatic polyester amide resins are widely used in various applications as engineering plastics having excellent mechanical properties, thermal properties, and molding processability. In particular, they are suitably used for electrical and electronic components such as connectors that require good fluidity.

[0003] In addition, with the recent miniaturization and weight reduction of devices, mechanical parts, electrical and electronic parts, etc. are becoming thinner and more complex in shape. Therefore, mechanical parts, electrical and electronic parts, etc. are often manufactured as composite molded products of metal and a liquid crystalline resin composition.

[0004] On the other hand, the liquid crystalline resin composition used for the above-mentioned parts has a high melting point and a high solidification rate. Therefore, in an insert molded product integrally molded with metal by injection molding, since the thermal conductivity of the metal is high, the solidification of the liquid crystalline resin composition proceeds quickly, and sufficient adhesion may not be obtained at the joint surface between the liquid crystalline resin composition and the metal member. Therefore, high adhesion between the metal part and the liquid crystalline resin composition is required.

[0005] For example, in Patent Document 1, in order to obtain good adhesion with metal, a liquid crystal polyester containing at least an aromatic hydroxycarboxylic acid, an aromatic dicarboxylic acid, a diol component, and a specific phosphorus compound as a main chain constituent compound component has been proposed.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

[0007] However, the liquid crystal polyester described in Patent Document 1 solidifies quickly, so it solidifies before it can bond with the metal member, making it difficult to obtain sufficient bonding strength at the bonding surface between the metal member and the liquid crystal polyester. In addition, because liquid crystal polyester has a high melting point, during extrusion and molding, the phosphorus compounds it contains can cause decomposition of the liquid crystal polyester, or corrosion of metal parts such as screws, barrels, and molds of extruders and molding machines.

[0008] The present invention has been made in view of the above, and aims to provide a liquid crystalline resin composition with excellent bonding strength with metal members, a metal-liquid crystalline resin composite using the same, and a method for manufacturing the same. [Means for solving the problem]

[0009] As a result of diligent research, the inventors have found that the above problems can be solved by a specific liquid crystalline resin composition and a metal member with surface treatment, and have completed the following invention. Specifically, the present invention provides the following [1] to [5].

[0010] [1] A liquid crystalline resin composition used in the manufacture of a metal-liquid crystal resin composite, The liquid crystalline resin composition comprises a liquid crystalline resin and an inorganic filler. The loss factor at the crystallization temperature (Tc) of the aforementioned liquid crystalline resin composition is 0.20 or higher. Liquid crystalline resin composition. [2] The liquid crystalline resin comprises two or more constituent units selected from the following constituent units (I) to (VI): The content of constituent unit (I) is 30 mol% or more and 80 mol% or less relative to the total constituent units. The content of constituent unit (II) is 0 mol% or more and less than 70 mol% relative to the total constituent units. The content of constituent unit (III) is between 0 mol% and 30 mol% relative to the total constituent units. The content of constituent unit (IV) is 0 mol% or more and less than 20 mol% relative to the total constituent units. The content of constituent unit (V) is between 0 mol% and 30 mol% relative to the total number of constituent units. The content of constituent unit (VI) is between 0 mol% and 30 mol% relative to the total constituent units. The total content of constituent units (I) to (VI) is 100 mol% of the total constituent units. The liquid crystalline resin composition described in [1] above.

[0011] [ka] [3] A metal-liquid crystal resin composite having a metal member and a liquid crystal resin composition, The metal-liquid crystal resin composite has a bonding surface where the metal member and the liquid crystal resin composition are joined. The liquid crystalline resin composition comprises a liquid crystalline resin and an inorganic filler. The loss coefficient of the crystalline resin composition at the crystallization temperature (Tc) is 0.20 or higher. The bonding surface on the metal member side is a metal-liquid crystal resin composite that has undergone surface treatment. [4] The process of preparing metal components, A step of preparing a liquid crystalline resin composition, The process includes a step of injection molding the liquid crystalline resin composition onto the metal member to form a metal-liquid crystalline resin composite in which the metal member and the liquid crystalline resin composition are bonded together, The liquid crystalline resin composition comprises a liquid crystalline resin and an inorganic filler. The loss coefficient of the crystalline resin composition at the crystallization temperature (Tc) is 0.20 or higher. The aforementioned metal component is a metal-liquid crystal resin composite that has been surface-treated. [5] The method for producing a metal-liquid crystal resin composite according to [4], wherein the surface treatment is a chemical surface treatment or a physical surface treatment. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a liquid crystalline resin composition excellent in bonding strength with a metal member, a metal-liquid crystalline resin composite using the same, and a method for producing the same.

Brief Description of Drawings

[0013] [Figure 1] FIG. 1a is a plan view of a test piece for measuring the bonding strength of the metal-liquid crystalline resin composite of the present invention. FIG. 1b is a side view of a test piece for measuring the bonding strength of the metal-liquid crystalline resin composite of the present invention.

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0015] 1. Metal-Liquid Crystalline Resin Composite The metal-liquid crystalline resin composite of the present invention contains a metal member and a liquid crystalline resin composition as constituent components. Hereinafter, each component will be described.

[0016] [Metal Member] The type of the metal member used in the present invention is not particularly limited, but it is preferably selected from copper, copper alloy, aluminum, aluminum alloy, magnesium alloy, iron, zinc, nickel, and the like. Among these, from the viewpoint of the difference in the coefficient of linear expansion with the liquid crystalline resin, copper alloy and aluminum are preferable.

[0017] In addition, the metal member of the present invention has a bonding surface that bonds to the liquid crystalline resin composition described later. From the viewpoint of the bonding strength with the liquid crystalline resin composition, the bonding surface is subjected to a surface treatment by chemical surface treatment or physical surface treatment.

[0018] (Chemical Surface Treatment) In the present invention, the "chemical surface treatment" refers to a surface treatment method that causes a chemical bond such as a covalent bond, hydrogen bond, or intermolecular force between the surface of the metal member (bonding surface with the liquid crystalline resin composition) and the liquid crystalline resin composition.

[0019] Examples of chemical surface treatments include chemical etching (surface roughening), surface modification treatments such as corona treatment and plasma treatment (to impart hydrophilicity to the surface), thin film formation on the surface using a mixed solution of a corrosion inhibitor and an acidic aqueous solution such as hydrochloric acid or sulfuric acid, or thin film formation on the surface using a triazinethiol compound disclosed in Japanese Patent Application Publication No. 2000-218935. Furthermore, examples of chemical treatments when the metal component is aluminum include hydrated oxide formation on the surface by hot water treatment disclosed in Japanese Patent Application Publication No. Hei 8-142110. Chemical surface treatments may be performed using only one method or in combination of two or more methods.

[0020] (Physical surface treatment) In this invention, "physical surface treatment" refers to a surface treatment method that uses physical means to form fine irregularities on the surface of a metal member (the side that is bonded to the liquid crystalline resin composition).

[0021] Examples of physical surface treatments include laser irradiation, sandblasting, shot blasting, tumbling, and wet blasting. Physical surface treatments may be performed using only one method or in combination of two or more methods.

[0022] The surface roughness (Rz) of the metal component after surface treatment is preferably 0.5 μm to 50 μm, and more preferably 1 μm to 20 μm, based on a ten-point average roughness (Rz) measured in accordance with JIS B 0601. A ten-point average roughness (Rz) of 0.5 μm to 50 μm provides a surface roughness that allows for sufficient bonding strength between the metal component and the liquid crystalline resin.

[0023] [Liquid crystal resin composition] The liquid crystalline resin composition of the present invention comprises a liquid crystalline resin and an inorganic filler. The loss factor of the liquid crystalline resin composition at the crystallization temperature (Tc: 230~380°C) is 0.20 or higher, preferably 0.20 to 0.55, and more preferably 0.21 to 0.45. A loss factor of 0.20 or higher indicates high viscosity, which reduces hesitation, pressure loss during injection, and delamination at the bonding surface due to solidification, thus enabling high bonding strength. The crystallization temperature (Tc) of the liquid crystalline resin composition can be determined, for example, using DSC (manufactured by TA Instruments). The loss factor can be determined, for example, using RSAIII (manufactured by Rheometric Scientific).

[0024] Furthermore, the melting point (Tm) of the liquid crystalline resin composition of the present invention is preferably 230°C or higher and 400°C or lower, and more preferably 240°C or higher and 370°C or lower. A lower melting point (Tm) of the liquid crystalline resin composition results in higher bonding strength with metals, but insufficient heat resistance. If the melting point is 230°C or higher, it can be used for surface mount components that require reflow soldering, and if it is 400°C or lower, existing molding machines can be used. The melting point (Tm) can be determined, for example, using a DSC (manufactured by TA Instruments).

[0025] (Liquid crystal resin) The liquid crystalline resin of the present invention is a component of a liquid crystalline resin composition to be bonded to the bonding surface of a metal member. The type of liquid crystalline resin is not particularly limited, but it is preferably at least one resin selected from aromatic polyesters and aromatic polyesteramides. Furthermore, the liquid crystalline resin may also include polyesters that partially contain aromatic polyesteramide in the same molecular chain.

[0026] The aromatic polyester or aromatic polyesteramide used as the liquid crystalline resin applicable to the present invention is particularly preferably an aromatic polyester or aromatic polyesteramide having repeating units derived from aromatic hydroxycarboxylic acid as constituent components. Specifically, the liquid crystalline resin can be any of the following resins (1) to (5).

[0027] (1) Polyesters consisting mainly of repeating units derived from one or more aromatic hydroxycarboxylic acids and their derivatives;

[0028] (2) A polyester comprising repeating units mainly derived from one or more aromatic hydroxycarboxylic acids and their derivatives, and repeating units derived from one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and their derivatives;

[0029] (3) A polyester comprising repeating units mainly derived from one or more aromatic hydroxycarboxylic acids and their derivatives; repeating units derived from one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and their derivatives; and repeating units derived from at least one or more aromatic diols, alicyclic diols, aliphatic diols, and their derivatives;

[0030] (4) Polyesteramides comprising repeating units mainly derived from one or more aromatic hydroxycarboxylic acids and their derivatives; repeating units derived from one or more aromatic hydroxyamines, aromatic diamines, and their derivatives; and repeating units derived from one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and their derivatives;

[0031] (5) Polyesteramides comprising repeating units mainly derived from one or more aromatic hydroxycarboxylic acids and their derivatives; repeating units derived from one or more aromatic hydroxyamines, aromatic diamines, and their derivatives; repeating units derived from one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and their derivatives; and repeating units derived from at least one or more aromatic diols, alicyclic diols, aliphatic diols, and their derivatives.

[0032] Specific examples of compounds constituting the above-mentioned liquid crystalline resin include aromatic hydroxycarboxylic acids such as p-hydroxybenzoic acid containing the following structural unit (I) and 6-hydroxy-2-naphthoic acid containing the following structural unit (II); aromatic dicarboxylic acids such as terephthalic acid containing the following structural unit (III), isophthalic acid containing the following structural unit (IV), and 4,4'-diphenyldicarboxylic acid and 2,6-naphthalenedicarboxylic acid containing other structural units; aromatic diols such as 4,4'-dihydroxybiphenyl containing the following structural unit (V), and 2,6-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, hydroquinone, and resorcinol containing other structural units; and aromatic amines such as p-aminophenol containing the following structural unit (VI) and p-phenylenediamine containing other structural units.

[0033] [ka]

[0034] The above-mentioned compounds having ester-forming ability may be used in polymerization in their original form, or they may be modified from precursors into derivatives having ester-forming ability in a step prior to polymerization.

[0035] Furthermore, the content of the above-mentioned constituent unit (I) is preferably 30 mol% to 80 mol%, and more preferably 35 mol% to 70 mol%, relative to the total constituent units. The content of constituent unit (II) is preferably 0 mol% or more and less than 70 mol%, and preferably 3 mol% or more and 60 mol% or less, relative to the total constituent units. The content of constituent unit (III) is preferably 0 mol% to 30 mol%, and more preferably 5 mol% to 25 mol%, relative to the total constituent units. The content of constituent unit (IV) is preferably 0 mol% or more and less than 30 mol%, and preferably 5 mol% or more and 25 mol% or less, relative to the total constituent units. The content of constituent unit (V) is preferably 0 mol% to 30 mol%, and more preferably 5 mol% to 25 mol%, relative to the total number of constituent units. The content of constituent unit (VI) is preferably 0 mol% to 30 mol%, and more preferably 0 mol% to 15 mol%, relative to the total constituent units. The total content of constituent units (I) to (VI) is 100 mol% of the total constituent units.

[0036] Here, if the content of the above-mentioned constituent unit (II) is 0 mol% or more, it becomes easier to improve the heat resistance of the liquid crystalline resin composition, and if the content of the above-mentioned constituent unit (II) is less than 70 mol%, the decrease in the loss coefficient of the liquid crystalline resin composition can be reduced.

[0037] Furthermore, examples of compounds constituting the above-mentioned liquid crystalline resin include compounds represented by the following general formulas (VII) to (IX). Specific examples of these include aromatic diols such as compounds represented by general formulas (VII) and (VIII); and aromatic dicarboxylic acids such as compounds represented by the following general formula (IX).

[0038] [ka]

[0039] In formula (VII), X is a group selected from alkylene (carbon number C1 to C4), alkylidene, -O-, -SO-, -SO2-, -S-, and -CO-.

[0040] In equation (IX), Y is -(CH2) n -(n=1~4) and -O(CH2) n It is a group selected from O-(n=1~4).

[0041] The most preferred liquid crystalline resin that can be used in the present invention preferably contains two or more constituent units selected from the above-described constituent units (I) to (VI).

[0042] Furthermore, the above-mentioned liquid crystalline resin may contain molecular weight modifiers in addition to the above-mentioned components, as needed.

[0043] (Method for preparing liquid crystalline resin) The liquid crystalline resin of the present invention can be prepared from the above-mentioned compounds (monomers) or mixtures thereof by known methods such as direct polymerization or transesterification. Examples of known methods include melt polymerization, solution polymerization, slurry polymerization, solid-phase polymerization, or combinations of two or more of these. Among the above methods, melt polymerization or a combination of melt polymerization and solid-phase polymerization is preferred.

[0044] In the method for preparing (polymerizing) the liquid crystalline resin of the present invention, various catalysts can be used. Examples of the catalysts 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), as well as organic compound catalysts such as N-methylimidazole and 4-dimethylaminopyridine.

[0045] The amount of catalyst used is generally preferably 0.001 to 1% by mass, and more preferably 0.01 to 0.2% by mass, relative to the total mass of the monomer. If necessary, the polymers produced by these polymerization methods can be further increased in molecular weight by solid-phase polymerization, which involves heating under reduced pressure or in an inert gas.

[0046] The melt viscosity of the liquid crystalline resin obtained by the above method is preferably 10 to 30°C higher than the melting point measured by differential scanning calorimeter, and the shear rate is 1000 sec. -1 The melt viscosity measured is preferably 3 Pa·s to 200 Pa·s, more preferably 5 Pa·s to 100 Pa·s, and particularly preferably 5 Pa·s to 50 Pa·s. If the melt viscosity of the liquid crystalline resin is 3 Pa·s or higher, backflow and spurting problems during molding can be suppressed, and if it is 200 Pa·s or lower, the liquid crystalline resin composition can fill even the fine surface of the metal member. The melt viscosity can be measured, for example, using a capillary rheometer Capillograph 1D (manufactured by Toyo Seiki Seisakusho Co., Ltd.). The above liquid crystalline resin may be a mixture of two or more liquid crystalline resins.

[0047] [Inorganic filler] Examples of inorganic fillers of the present invention include talc, silica, mica, glass fibers, whiskers, and wollastonite. By including inorganic fillers, the heat resistance and mechanical properties of the liquid crystalline resin composition can be improved, and the loss coefficient at the crystallization temperature (Tc) of the liquid crystalline resin composition can be adjusted. For example, talc, silica, mica, etc. tend to increase the loss coefficient, while glass fibers, whiskers, wollastonite, etc. tend to decrease the loss coefficient.

[0048] <Talc> In this specification, "talc" means hydrated magnesium silicate (Mg3Si4O 10 This refers to minerals whose main component is (OH)2.

[0049] The cumulative average particle size (D50) of talc usable in this invention, based on mass or volume, is preferably 4.0 to 20.0 μm, and more preferably 10.0 to 18.0 μm. An average particle size of 4.0 to 20.0 μm allows for the maintenance of the fluidity of the liquid crystalline resin composition and reduces warping deformation of molded articles using it. The above average particle size (D50) can be measured by laser diffraction.

[0050] The talc mentioned above may be a commercially available product. Examples of commercially available talc include Crown Talc PP (manufactured by Matsumura Sangyo Co., Ltd., "Crown Talc" is a registered trademark of the company), Talc Powder PKNN (manufactured by Hayashi Kasei Co., Ltd.), LMS-100, LMS-200, LMS-300, LMS-3500, LMS-400, LMP-100, PKP-53, PKP-80, and PKP-81 (all manufactured by Fuji Talc Industry Co., Ltd.), D-600, D-800, D-1000, P-2, P-3, P-4, P-6, P-8, and SG-95 (all manufactured by Nippon Talc Co., Ltd.), etc.

[0051] <Silica> In this specification, "silica" means silicon dioxide (SiO2) or any substance composed of silicon dioxide. Examples of silica that can be used in the present invention include fused silica, spherical silica, amorphous silica, crystalline silica, colloidal silica, precipitated silica, fumed silica, and dry silica. Among these, spherical silica is preferred.

[0052] Furthermore, the average particle size of the silica is preferably 0.1 to 50 nm, and more preferably 1 to 20 nm. When the average particle size of the silica is 1 to 10 μm, the rigidity can be improved without impairing fluidity or appearance. The average particle size of the silica can be measured by the cumulant method using a particle size distribution analyzer with dynamic light scattering.

[0053] The silica mentioned above may be a commercially available product. Examples of commercially available silica include Aerosil R-972 (manufactured by Nippon Aerosil Co., Ltd., "Aerosil" is a registered trademark of the company), Admafine SO-C2, SC2500-SQ, SC200G-SQ (manufactured by Admatex Co., Ltd., "Admafine" is a registered trademark of the company), X-24-9163A (manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

[0054] <Mica> In this specification, "mica" refers to pulverized silicate minerals containing aluminum, potassium, magnesium, sodium, iron, etc. Examples of mica that can be used in the present invention include muscovite, phlogopite, biotite, and artificial mica. By using mica, the resulting liquid crystalline resin composition can be given low warpage. Of these, muscovite, which has a good hue from an appearance viewpoint, is preferred.

[0055] When the mica is in granular form, the average particle size of the mica is preferably 10 to 100 μm, and more preferably 20 to 80 μm. An average particle size of 10 μm or more provides sufficient rigidity and weld strength to the molded product. Furthermore, an average particle size of 100 μm or less ensures sufficient fluidity for molding the metal-liquid crystal resin composite of the present invention. The average particle size of the mica can be measured by microtrac laser diffraction.

[0056] When the mica is in plate (layer) form, the thickness of the mica is preferably 0.01 to 1 μm, and more preferably 0.03 to 0.3 μm. When the mica thickness is 0.01 to 1 μm, the mica is less likely to crack during the melting process of the liquid crystalline resin composition, thus making it easier to improve the rigidity of the molded product. Here, the thickness of the mica refers to the height dimension in the vertical direction (minor axis) of the center of the mica in the width direction (long axis). Note that the thickness of the mica is the thickness measured by observation with an electron microscope.

[0057] In this invention, it is preferable to use thinly and finely ground mica for the reason that mica having the above-mentioned average particle size or thickness can be obtained. In particular, in this invention, it is preferable to use mica produced by a wet grinding method. Furthermore, the mica may be surface-treated with a silane coupling agent or the like, or it may be granulated with a binder to form granules.

[0058] The above mica may be a commercially available product. Examples of commercially available mica include A-51S (average aspect ratio 85, volume average particle size 52 μm), SYA-31RS (average aspect ratio 90, volume average particle size 40 μm), SYA-21RS (average aspect ratio 90, volume average particle size 27 μm), SJ-005 (average aspect ratio 30, volume average particle size 5 μm), and AB-25S (average aspect ratio 80, average particle size). This includes particles with a diameter of 24 μm (all manufactured by Yamaguchi Mica Co., Ltd.), etc.

[0059] <Glass fiber> In this specification, "glass fiber" means a fibrous material whose cross-sectional shape, when cut perpendicular to the length, is circular or polygonal. Examples of glass fibers that can be used in the present invention include A glass, C glass, E glass, R glass, D glass, M glass, and S glass. Among these, E glass (alkali-free glass) is preferred from the viewpoint of linear expansion coefficient and electrical insulation properties.

[0060] The glass fibers described above preferably have a number-average fiber diameter of 1 to 25 μm, and more preferably 5 to 17 μm. By setting the number-average fiber diameter to 1 to 25 μm, the moldability of the liquid crystalline resin composition is further improved.

[0061] The glass fibers may take any form, such as glass roving made by continuously winding single fibers or multiple twisted single fibers, chopped strands (glass fibers with a number-average fiber length of 1 to 10 mm) cut to a length of 1 to 10 mm, or milled fibers (glass fibers with a number-average fiber length of 10 to 500 μm) crushed to a length of approximately 10 to 500 μm. These may be used individually or in combination of two or more types.

[0062] Furthermore, the glass fibers may have an irregular cross-sectional shape. The above-mentioned irregular cross-sectional shape refers to a cross-sectional shape in which the flattening ratio, indicated by the major axis / minor axis ratio of the cross-section perpendicular to the length direction of the fiber, is, for example, 1.5 to 10. When the glass fibers are flattened, low warping can be imparted to the liquid crystalline resin composition. In the present invention, when using glass fibers with an irregular cross-sectional shape, the above-mentioned flattening ratio is preferably 2.5 to 10, more preferably 2.5 to 8, and particularly preferably 2.5 to 5. When the flattening ratio is 2.5 to 10, fluidity is improved and impact resistance is also good.

[0063] The glass fibers mentioned above may be commercially available products. Examples of commercially available glass fibers include CS3J-257, CSG3PA-830 (both manufactured by Nitto Boseki Co., Ltd.), and ECS03T-786H (manufactured by Nippon Electric Glass Co., Ltd.).

[0064] Furthermore, the glass fibers mentioned above may be surface-treated with, for example, silane compounds, epoxy compounds, or urethane compounds, or oxidized, in order to improve their affinity with the resin components.

[0065] <Whisker> In this specification, "whiskers" refer to needle-shaped inorganic fillers that are elongated crystalline structures (whiskers) with a cross-sectional diameter of approximately 1 μm or less. Examples of whiskers include silicon carbide, silicon nitride, zinc oxide, alumina, calcium titanate, potassium titanate, barium titanate, aluminum borate, magnesium borate, calcium silicate, calcium carbonate, and magnesium oxysulfate.

[0066] In particular, using borates such as aluminum borate and magnesium borate not only reduces the linear expansion coefficient of the liquid crystalline resin composition because they have a very low coefficient of thermal expansion, but also increases the strength of the surface layer of the liquid crystalline resin composition, thereby improving the adhesion between the liquid crystalline resin composition and the metal component.

[0067] Furthermore, when using titanates such as potassium titanate, calcium titanate, and barium titanate, the adhesion between the liquid crystalline resin composition and the metal component can be improved, similar to the case with borates.

[0068] The whiskers mentioned above may be commercially available products. Examples of commercially available whiskers include TISMO N102, TISMO D102, TISMO D102SG (manufactured by Otsuka Chemical Co., Ltd.), etc.

[0069] Furthermore, when molding a molded product using needle-shaped whiskers, the anisotropy caused by the orientation of the inorganic filler (needle-shaped whiskers) perpendicular to the flow direction of the liquid crystalline resin composition is mitigated compared to fibrous fillers with long fiber lengths. This makes it possible to reduce the difference in linear expansion coefficient and molding shrinkage coefficient between the flow direction and the direction perpendicular to it of the liquid crystalline resin composition of the molded product.

[0070] <Wollastnight> In this specification, "wolllastonite" means silicate minerals (CaO·SiO2).

[0071] The fiber diameter of the wollastonite used in this invention is preferably 0.1 to 10 μm, more preferably 0.1 to 5 μm, and particularly preferably 0.1 to 3 μm. Furthermore, its aspect ratio (average fiber length / average fiber diameter) is preferably 3 to 30. The fiber diameter can be determined by observing the reinforcing filler with an electron microscope, determining the diameter of individual fibers, and calculating the number-average fiber diameter from these measurements.

[0072] Wollastonite may be surface-treated with various surface treatment agents such as silane coupling agents, higher fatty acid esters, and waxes. Furthermore, it may be granulated with various resins, higher fatty acid esters, and waxes as sizing agents to form granules.

[0073] The above-mentioned wollastonite may be a commercially available product. Examples of commercially available wollastonite include NYAD-G, NYAD 400, NYAD 1250, and NYGLOS 4W (all manufactured by Imerys, Inc. (USA)).

[0074] The fiber diameters of the glass fibers and wollastonite mentioned above can be measured, for example, using the dynamic image analysis / particle (state) analyzer "PITA-3" (manufactured by Seishin Corporation) or the fibrous particle measurement system "Luzex" (manufactured by Nireco Corporation; Luzex is a registered trademark of the company).

[0075] [Other ingredients] The liquid crystalline resin composition according to the present invention may also contain other polymers, other fillers, stabilizers such as antioxidants and ultraviolet absorbers commonly added to synthetic resins, antistatic agents, flame retardants, colorants such as dyes and pigments, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents, and other components as appropriate, depending on the required performance. Only one of these other components may be used, or two or more may be used in combination.

[0076] (Liquid crystal resin composition) The liquid crystalline resin composition of the present invention preferably contains the above-mentioned liquid crystalline resin in an amount of 60.0% to 90.0% by mass, more preferably 62.0% to 85.0% by mass, and even more preferably 65.0% to 80.0% by mass, based on the total mass of the liquid crystalline resin composition. When the liquid crystalline resin content is 60.0% to 90.0% by mass, the composition has good fluidity, can fill even the fine details of surface-treated metal components, and allows for easy adjustment of the load deflection temperature and flexural modulus at high temperatures of the formed molded product to a preferred range.

[0077] The liquid crystalline resin composition of the present invention preferably contains the above-mentioned inorganic filler in an amount of 2% to 50% by mass, and more preferably 5% to 40% by mass, based on the total mass of the liquid crystalline resin composition. When the content of the above-mentioned inorganic filler is 5% to 40% by mass, heat resistance and mechanical properties can be improved without impairing fluidity or appearance.

[0078] Furthermore, the liquid crystalline resin composition of the present invention may use only one of the above-mentioned inorganic fillers alone, or two or more types in combination.

[0079] 2. Method for manufacturing metal-liquid crystal resin composites The present invention provides a method for producing a metal-liquid crystal resin composite. (1) The process of preparing metal components, (2) A step of preparing a liquid crystal resin composition, (3) The process includes a step of injection molding the liquid crystalline resin composition onto the metal member to form a metal-liquid crystalline resin composite in which the metal member and the liquid crystalline resin composition are joined together.

[0080] The metal-liquid crystal resin composite manufactured by the above manufacturing method has a bonding surface of the metal component that is bonded to the liquid crystal resin composition, which is subjected to chemical or physical surface treatment, and the loss factor at the crystallization temperature (Tc) of the liquid crystal resin composition is 0.20 or higher.

[0081] (Process (1)) Step (1) is a step in which the metal component is prepared by applying the chemical or physical surface treatment described above.

[0082] (Chemical surface treatment) The chemical surface treatment in this process refers to a treatment that creates chemical bonds, such as covalent bonds, hydrogen bonds, or intermolecular forces, between the surface of a metal component and a liquid crystalline resin composition. The chemical surface treatment can be appropriately selected depending on the type of metal component. For example, if a copper alloy is selected as the metal component, a surface treatment can be applied to form a thin film on the copper component surface using a triazinethiol compound. If aluminum is selected as the metal component, a surface treatment can be applied to form a hydrated oxide on the aluminum surface by hot water treatment. Note that the above chemical treatment may be performed using only one method, or two or more methods may be used in combination. Furthermore, a step of treating with a molecular improver or the like after the above chemical surface treatment may also be included.

[0083] (Physical surface treatment) In this process, physical surface treatment refers to a process that creates fine irregularities on the surface of a metal component. For example, the physical surface treatment can be appropriately selected depending on the type of metal component. For instance, if aluminum is selected as the metal component, a wet blasting process can be used to create fine irregularities on the surface (with a ten-point mean roughness (Rz) of 0.5 μm to 50 μm). The physical surface treatment may use only one method, or two or more methods may be used in combination.

[0084] (Process (2)) Step (2) is a step of preparing the above-mentioned liquid crystalline resin composition. First, the above-mentioned liquid crystalline resin is prepared, and the liquid crystalline resin composition can be produced by kneading the above liquid crystalline resin, an inorganic filler, and any additives, etc., using a known method, for example, a twin-screw extruder (for example, TEX-30α, manufactured by Japan Steel Works Ltd.). The above liquid crystalline resin may have a step of forming it into pellets before it becomes a liquid crystalline resin composition. One method of forming it into pellets is to use a strand cutter.

[0085] (Step (3)) Step (3) is a step of injection molding the liquid crystalline resin composition onto the metal member to form a metal-liquid crystalline resin composite of the liquid crystalline resin composition and the metal member. Specifically, the metal member that has undergone the chemical or physical surface treatment described above is fixed to a mold, and the liquid crystalline resin composition is injection molded onto it to form a metal-liquid crystalline resin composite. [Examples]

[0086] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, experiments and measurements were performed under an atmosphere of 23°C and 50% RH.

[0087] 1. Preparation of liquid crystalline resin Liquid crystal resins (A)-1 to (A)-4 were prepared using the following raw materials (monomers, fatty acid metal salt catalysts, and acylating agents) according to the preparation method shown below.

[0088] (Liquid crystal resin (A)-1) [Raw materials] (monomer) (I) 4-Hydroxybenzoic acid: 1385g (60 mol%) (II) 6-Hydroxy-2-Naphthoic Acid: 88g (5 mol%) (III) Terephthalic acid: 504g (17 mol%) (V) 4,4'-Dihydroxybiphenyl: 415g (13 mol%) (VI) N-acetyl-p-aminophenol: 126 g (5 mol%) (Fatty acid metal salt catalyst) Potassium acetate catalyst: 120 mg (Acylating agent) Acetic anhydride: 1662g

[0089] [Adjustment method] After charging the above raw materials into a polymerization vessel equipped with a stirrer, reflux column, monomer inlet, nitrogen inlet, and vacuum / outlet line, the polymerization vessel was purged with nitrogen, the temperature of the reaction system was raised to 140°C, and the reaction was carried out at 140°C for 1 hour. Then, the temperature was raised to 360°C over 5.5 hours, and from there the pressure was reduced to 10 Torr (i.e., 1330 Pa) over 20 minutes, and melt polymerization was carried out while distilling off acetic acid, excess acetic anhydride, and other low-boiling components to prepare liquid crystalline resin (A)-1. After the stirring torque reached a predetermined value, nitrogen was introduced to change the state from vacuum to atmospheric pressure and then to pressurized pressure, and the liquid crystalline resin (A)-1 was discharged from the polymerization vessel from the bottom, extruded into strands, and pelletized to obtain pelletized liquid crystalline resin (A)-1. The melting point (Tm) of the obtained liquid crystalline resin (A)-1 was 335°C, and the crystallization temperature (Tc) was 291°C. The melting point and crystallization temperature were measured using a DSC (TA Instruments).

[0090] (Liquid crystal resin (A)-2) [Raw materials] (monomer) (I) 4-Hydroxybenzoic acid: 1040g (48 mol%) (II) 6-Hydroxy-2-Naphthoic Acid: 89g (3 mol%) (III) Terephthalic acid: 547g (21 mol%) (IV) Isophthalic acid: 91g (3.5 mol%) (V) 4,4'-Dihydroxybiphenyl: 716g (24.5 mol%) (Fatty acid metal salt catalyst) Potassium acetate catalyst: 110 mg (Acylating agent) Acetic anhydride: 1644g

[0091] [Adjustment method] After charging the above raw materials into a polymerization vessel equipped with a stirrer, reflux column, monomer inlet, nitrogen inlet, and vacuum / outlet line, the polymerization vessel was purged with nitrogen, the temperature of the reaction system was raised to 140°C, and the reaction was carried out at 140°C for 1 hour. Then, the temperature was raised to 360°C over 5.5 hours, and from there the pressure was reduced to 5 Torr (i.e., 667 Pa) over 20 minutes, and melt polymerization was carried out while distilling off acetic acid, excess acetic anhydride, and other low-boiling components to prepare liquid crystalline resin (A)-2. After the stirring torque reached a predetermined value, nitrogen was introduced to change the state from vacuum to atmospheric pressure and then to pressurized pressure, and the liquid crystalline resin (A)-2 was discharged from the polymerization vessel from the bottom, extruded into strands, and pelletized to obtain pelletized liquid crystalline resin (A)-2. The melting point (Tm) of the obtained liquid crystalline resin (A)-2 was 355°C, and the crystallization temperature (Tc) was 310°C.

[0092] (Liquid crystal resin (A)-3) Liquid crystalline resin (A)-3 was prepared in the same manner as liquid crystalline resin (A)-2, except that the raw materials used in liquid crystalline resin (A)-2 were changed to the following raw materials. The melting point (Tm) of the obtained liquid crystalline resin (A)-3 was 282°C, and the crystallization temperature (Tc) was 241°C. [Raw materials] (monomer) (I) 4-Hydroxybenzoic acid: 1679g (73 mol%) (II) 6-hydroxy-2-naphthoic acid: 801 g (27 mol%) (Fatty acid metal salt catalyst) Potassium acetate catalyst: 110 mg (Acylating agent) Acetic anhydride: 1644g

[0093] (Liquid crystal resin (A)-4) Liquid crystalline resin (A)-4 was prepared in the same manner as liquid crystalline resin (A)-1, except that the raw materials used in liquid crystalline resin (A)-1 were changed to the following raw materials. The melting point (Tm) of the obtained liquid crystalline resin (A)-4 was 360°C, and the crystallization temperature (Tc) was 318°C. [Raw materials] (monomer) (I) 4-Hydroxybenzoic acid: 46 g (2 mol%) (II) 6-Hydroxy-2-Naphthoic Acid: 845g (48 mol%) (III) Terephthalic acid: 741g (25 mol%) (V) 4,4'-Dihydroxybiphenyl: 798g (25 mol%) (Fatty acid metal salt catalyst) Potassium acetate catalyst: 120 mg (Acylating agent) Acetic anhydride: 1644g

[0094] (Inorganic filler (B)) (B)-1: Talc (Crown Talc PP (average particle size 14 μm), manufactured by Matsumura Sangyo Co., Ltd.) (B)-2: Glass fiber (CS 3J-257 (fiber diameter 11 μm), manufactured by Nitto Boseki Co., Ltd.) (B)-3: Wollastonite (NYGLOS 8 (fiber diameter 12 μm), manufactured by Imerys, Inc. (USA)) Note that the average particle diameter listed in (B)-1 and the fiber diameter in (B)-3 are catalog values, while the fiber diameter in (B)-2 is a measured value.

[0095] (Other ingredients) Lubricant: Pentaerythritol stearate (manufactured by Emery Oleochemicals Japan)

[0096] 2. Preparation of liquid crystalline resin composition (Example 1) A liquid crystalline resin composition was obtained by supplying liquid crystal resin (A)-1 (67.7% by mass) from the main feed port of a twin-screw extruder (TEX-30α, manufactured by Japan Steel Works Ltd.), and supplying inorganic filler (B)-1 (22% by mass), inorganic filler (B)-2 (10% by mass), and lubricant (0.3% by mass) from the side feed port and mixing them. The temperature of the cylinder located at the main feed port of the twin-screw extruder was set to 280°C, and the temperature of all other cylinders was set to 360°C.

[0097] (Example 2, Comparative Examples 2, 3, 4, and 7) The liquid crystalline resin compositions of Example 2, Comparative Examples 2, 3, 4, and 7 were obtained using the same preparation method as in Example 1, except that the liquid crystalline resin and / or inorganic filler shown in Table 1 was changed.

[0098] (Example 3 and Comparative Example 5) The liquid crystalline resin compositions of Example 3 and Comparative Example 5 were obtained using the same preparation method as in Example 1, except that the liquid crystalline resin and / or inorganic filler shown in Table 1 was changed, the temperature of the cylinder provided at the main feed port was changed from 280°C to 250°C, and the temperature of all other cylinders was changed from 360°C to 320°C.

[0099] (Comparative Examples 1 and 6) The liquid crystalline resin compositions of Comparative Examples 1 and 6 were obtained using the same preparation method as in Example 1, except that the liquid crystalline resin and / or inorganic filler shown in Table 1 was changed, the temperature of the cylinder provided at the main feed port was set to 280°C, and the temperature of all other cylinders was changed from 360°C to 370°C.

[0100] 3. Measurement of physical properties [Measurement of melting point (Tm) and crystallization temperature (Tc)] The melting point (Tm) and crystallization temperature (Tc) of the liquid crystalline resin compositions shown in Table 1 were measured by the following method. (Measurement method) The endothermic peak temperature (Tm) in °C was observed when the liquid crystalline resin composition was heated from room temperature at a rate of 20 °C / min. After observing the endothermic peak temperature, the composition was held at (Tm + 40) °C for 2 minutes, and then cooled at a rate of 20 °C / min to observe the exothermic peak temperature (Tc). The melting point (Tm) [°C] and crystallization temperature (Tc) [°C] are as shown in Table 1. The melting point and crystallization temperature were measured using a DSC (TA Instruments Corporation).

[0101] [Measurement of loss factor] The loss coefficients of the liquid crystalline resin compositions shown in Table 1 were measured by the following method. (Measurement method) A crystalline resin composition was injection molded using an injection molding machine (SE100DU, Sumitomo Heavy Industries) to produce test specimens measuring 130 × 12.7 × 1.6 mm. The loss coefficient of the obtained test specimens was measured using a three-point bending test method with a span of 40 mm under conditions of a frequency of 1 Hz and a heating rate of 2 °C / min. The loss coefficient was determined using a viscoelasticity analyzer RSAIII (Rheometric Scientific).

[0102] [Surface treatment method for metal components] (Surface treatment 1: Chemical surface treatment) A bonding surface made of triazinethiol compounds was formed on a copper (C1100) piece measuring 18 mm x 45 mm x 1.5 mm thick by surface treatment using Toa Denka Co., Ltd.'s TRI technology (International Publication No. 2020 / 059651, etc.).

[0103] (Surface treatment 2: Physical surface treatment) An 18mm x 45mm x 1.5mm thick aluminum (A5052) sample was placed in a Fuji Seiki LH-5 wet blasting machine and polished with Fuji Brown alumina abrasive at a processing pressure of 0.4 MPa until the average surface roughness (Rz) reached 10 μm.

[0104] 4. Fabrication and evaluation of metal-liquid crystal resin composites [Fabrication of metal-liquid crystal resin composites] Using an injection molding machine (TR40VRE, manufactured by Sodick), the liquid crystalline resin composition shown in Table 1 was insert-molded into the surface-treated metal member described above, in accordance with ISO 19095-2:2015 "Overlapped test specimens (type B)", to obtain a metal-liquid crystalline resin composite (test specimen) for measuring the bonding strength. As shown in Figures 1a and 1b, the above test specimen consisted of a liquid crystalline resin member 1 (10 mm × 45 mm × 3 mm t) and a metal member 3 (18 mm × 45 mm × 1.5 mm t) with a bonding surface 2 (50 mm 2 It has a structure that is joined by ).

[0105] [Molding conditions] Molding machine: Sodick TR40VRE injection molding machine Cylinder temperature (temperature from the nozzle side (°C)): (Examples 1, 2, Comparative Examples 2, 3, 4, 7) 360-370-370-360-350-50 (Example 3, Comparative Example 5) 320-320-320-320-300-50 (Comparative Examples 1 and 6) 380-380-380-360-350-50 Mold temperature: 80℃ Injection speed: 100mm / sec Holding pressure: 50MPa Holding time: 5 seconds Cooling time: 15 seconds

[0106] [Evaluation of joint strength] The bonding strength between the metal component and the liquid crystalline resin composition constituting the metal-liquid crystal resin composite fabricated in accordance with the above ISO19095-2 (type B) was measured. (Measurement method) The tensile testing was performed using a tensile testing machine (Autograph AG-20kNXDplus, manufactured by Shimadzu Corporation) at a rate of 10 mm / min.

[0107] [Table 1]

[0108] As shown in Table 1, good bonding strength was obtained in Examples 1 to 3, where the loss factor of the liquid crystalline resin composition was 0.2 or higher. On the other hand, Comparative Example 1 to 3, where the loss factor was less than 0.2, showed good bonding strength. 2, and 6~ In case 7, delamination occurred and the desired bonding strength could not be obtained. Furthermore, as shown in Comparative Examples 3 to 7, when metal members without surface treatment were used, interfacial delamination occurred in all cases and the desired bonding strength could not be obtained. From this, it was found that high adhesion with the liquid crystalline resin composition can be obtained by chemically or physically surface treating the surface of the metal member (the bonding surface with the liquid crystalline resin). [Industrial applicability]

[0109] The liquid crystalline resin composition of the present invention exhibits excellent adhesion to metal components, making it effective for manufacturing insert molded products using this resin composition. Furthermore, these insert molded products are expected to contribute to the development of thinner mechanical parts, electrical and electronic components, and other applications where the wall thickness and shape complexity are increasing. [Explanation of symbols]

[0110] 1. Liquid crystal resin member 2. Joint surface between metal member and liquid crystal resin member 3 Metal components

Claims

1. A liquid crystalline resin composition used in the manufacture of metal-liquid crystalline resin composites, The liquid crystalline resin composition comprises a liquid crystalline resin and talc and glass fibers as inorganic fillers. The loss coefficient of the crystalline resin composition at the crystallization temperature (Tc) is 0.20 or more and 0.45 or less. Liquid crystalline resin composition.

2. The liquid crystalline resin comprises two or more constituent units selected from the following constituent units (I) to (VI): The content of constituent unit (I) is 30 mol% or more and 80 mol% or less relative to the total constituent units. The content of constituent unit (II) is 0 mol% or more and less than 70 mol% relative to the total constituent units. The content of constituent unit (III) is 0 mol% or more and 30 mol% or less relative to the total constituent units. The content of constituent units (IV) is 0 mol% or more and less than 20 mol% relative to the total number of constituent units. The content of constituent unit (V) is 0 mol% or more and 30 mol% or less relative to the total number of constituent units. The content of constituent unit (VI) is 0 mol% or more and 30 mol% or less relative to the total constituent units. The liquid crystalline resin composition according to claim 1, wherein the total content of constituent units (I) to (VI) is 100 mol% of the total constituent units. 【Chemistry 1】

3. A metal-liquid crystal resin composite comprising a metal member and a liquid crystal resin composition, The metal-liquid crystal resin composite has a bonding surface where the metal member and the liquid crystal resin composition are joined. The liquid crystalline resin composition comprises a liquid crystalline resin and an inorganic filler. The loss factor at the crystallization temperature (Tc) of the liquid crystalline resin composition is 0.20 or higher. The bonding surface on the metal member side is a metal-liquid crystal resin composite that has undergone surface treatment.

4. The process of preparing metal components, A step of preparing a liquid crystalline resin composition, The process includes a step of injection molding the liquid crystalline resin composition onto the metal member to form a metal-liquid crystalline resin composite in which the metal member and the liquid crystalline resin composition are bonded together, The liquid crystalline resin composition comprises a liquid crystalline resin and an inorganic filler. The loss factor at the crystallization temperature (Tc) of the liquid crystalline resin composition is 0.20 or higher. The aforementioned metal component is a metal-liquid crystal resin composite that has been surface-treated.

5. The method for producing a metal-liquid crystal resin composite according to claim 4, wherein the surface treatment is a chemical surface treatment or a physical surface treatment.

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