JP6164945B2 - Liquid crystalline resin composition for camera modules - Google Patents

Description

  The present invention relates to a liquid crystalline resin composition for camera modules.

  Liquid crystalline resins typified by liquid crystalline polyester resins are widely used as highly functional engineering plastics because they have excellent mechanical strength, heat resistance, chemical resistance, electrical properties and the like in a well-balanced manner. Recently, liquid crystal resins have been used for precision equipment parts by taking advantage of these features.

  In the case of precision equipment, particularly optical equipment with a lens, slight dust, dust, etc. affect the performance of the equipment. For example, in a part used in an optical device such as a camera module, if small dust, oil, or dust adheres to the lens, the optical characteristics of the camera module are significantly deteriorated. In order to prevent such deterioration of optical characteristics, the parts that make up the camera module (hereinafter sometimes referred to as “camera module parts”) are ultrasonically cleaned before being assembled and attached to the surface. Small dust, oil, dust, etc. are removed.

  As described above, the molded body formed by molding the liquid crystalline resin composition is easy to peel off because the molecular orientation of the polymer is particularly large in the surface portion. The fluffing phenomenon of peeling and fluffing occurs, and the fluffed raised portion causes small dust.

  Therefore, when the liquid crystalline resin composition is used as a raw material for camera module parts, a special liquid crystalline resin composition is used in which the surface of the molded body is not raised even when the molded body is ultrasonically cleaned. As a special liquid crystalline resin composition, a liquid crystalline resin composition for a camera module containing a liquid crystalline resin, a specific talc, and carbon black is disclosed (see Patent Document 1).

JP 2009-242453 A

  However, according to the study by the present inventors, the liquid crystalline resin composition for a camera module described in Patent Document 1 has insufficient suppression of raising of the surface of the molded article, and the molded article is more difficult to raise the surface of the molded article. A liquid crystalline resin composition for a camera module for manufacturing the above is required.

  Further, according to the study by the present inventors, when a molded product such as a lens holder is manufactured by molding a conventional liquid crystalline resin composition for a camera module, blistering occurs, and the camera module is There was a case that the operation was disturbed.

  Further, according to the study by the present inventors, when a molded product such as a lens holder housing is manufactured by molding a conventional liquid crystalline resin composition for a camera module, the molding shrinkage is too large or too small (expanded). There was a problem when assembling the camera module.

  The present invention has been made in order to solve the above-mentioned problems, and its purpose is to produce a camera module component that has a surface that is less likely to be raised, has high mechanical strength, is less likely to cause blistering, and has high dimensional stability. Therefore, it is providing the liquid crystalline resin composition for camera modules.

  The inventors of the present invention have made extensive studies to solve the above problems. As a result, surface raising can be suppressed by using a liquid crystalline resin composition for a camera module containing a liquid crystalline resin, a specific fibrous filler, and a specific copolymer in a specific ratio. I found it.

  Moreover, it discovered that generation | occurrence | production of a blister could be suppressed by using specific plate-like fillers, such as a talc, as 1 type of inorganic fillers. That is, by increasing the content of the plate-like filler, the melt viscosity of the liquid crystalline resin composition for camera modules is increased, so that the melt tension of the resin composition is increased, and air enters the molten resin. This prevented the generation of blisters.

  Although the fibrous filler has a high effect of suppressing napping and improvement of mechanical strength, the effect of increasing the melt viscosity is low. On the other hand, the plate filler has a high effect of increasing the melt viscosity, but suppresses napping. It is difficult to suppress both the occurrence of raising and the generation of blisters only by using either one because the effect and the improvement effect of mechanical strength are low, but a specific plate such as a specific fibrous filler and talc It has been found that by using a specific amount of the filler in combination with the filler, it is possible to achieve both napping suppression and blister suppression.

  Furthermore, it has been found that the dimensional stability can be improved by using a specific amount of a specific fibrous filler and a specific plate-like filler such as talc. The present inventors presume that the molding shrinkage in the flow direction of the liquid crystalline resin composition for a camera module is negative (that is, the resin composition expands), thereby reducing the dimensional stability. Therefore, the anisotropy is disturbed by adding the fibrous filler and the plate-like filler to the liquid crystalline resin composition for camera modules, and the molding shrinkage in the flow direction of the resin composition is positive (that is, Dimensional stability was increased by shifting to (shrinkage).

  As described above, it has been found that the above problems can be solved, and the present invention has been completed. More specifically, the present invention provides the following.

  (1) (A) Liquid crystalline resin, (B1) Fibrous filler and (B2) (B) Inorganic filler comprising plate-like filler, (C1) Olefin copolymer and (C2) Styrene copolymer It contains at least one (C) copolymer selected from polymers, the content of component (A) is 57 to 77% by mass, the content of component (B1) is 5 to 15% by mass, (B2 ) Component content is 6-18% by mass, (B) component content is 21-33% by mass, (C) component content is 2-10% by mass, (B1) fibrous filler Has an average fiber diameter of 1.0 μm or less and an average fiber length of 5 to 50 μm, the (B2) plate-like filler has an average particle diameter of 50 μm or less, and the (C1) olefin copolymer Is composed of α-olefin and glycidyl ester of α, β-unsaturated acid, and said (C2 Styrene copolymers, styrene and alpha, a camera module for a liquid crystal resin composition composed of a glycidyl ester of β- unsaturated acids.

  (2) The liquid crystalline resin composition for camera modules according to (1), wherein the (B2) plate-like filler has an average particle size of 10 to 20 μm.

  (3) The liquid crystalline resin composition for camera modules according to (1) or (2), further comprising (D) carbon black and having a content of 1 to 5% by mass.

  When a camera module part is manufactured using the liquid crystalline resin composition for a camera module of the present invention as a raw material, the part for the camera module has a highly resistant surface, high mechanical strength, less blistering, and high dimensional stability. Is obtained.

It is sectional drawing which shows a common camera module typically. In an Example and a comparative example, it is a top view which shows the molded object used in confirming the number of blister generation | occurrence | production samples. In an Example and a comparative example, it is a top view which shows the measurement location of the test piece dimension measured when calculating | requiring a mold shrinkage rate.

  Hereinafter, embodiments of the present invention will be described. In addition, this invention is not limited to the following embodiment.

<Liquid crystal resin composition for camera module>
The liquid crystalline resin composition for a camera module of the present invention contains (A) a liquid crystalline resin, (B) an inorganic filler, and (C) a copolymer.

[(A) Liquid crystalline resin]
The (A) liquid crystalline resin used in the present invention refers to a melt processable polymer having a property capable of forming an optically anisotropic molten phase. The property of the anisotropic molten phase can be confirmed by a conventional polarization inspection method using an orthogonal polarizer. More specifically, the anisotropic molten phase can be confirmed by using a Leitz polarizing microscope and observing a molten sample placed on a Leitz hot stage under a nitrogen atmosphere at a magnification of 40 times. When the liquid crystalline polymer applicable to the present invention is inspected between crossed polarizers, the polarized light is normally transmitted even in the molten stationary state, and optically anisotropic.

  Although it does not specifically limit as said kind of (A) liquid crystalline resin, It is preferable that it is aromatic polyester or aromatic polyester amide. Moreover, the polyester which partially contains aromatic polyester or aromatic polyester amide in the same molecular chain is also in that range. They preferably have a logarithmic viscosity (IV) of at least about 2.0 dl / g, more preferably 2.0-10.0 dl / g when dissolved in pentafluorophenol at 60 ° C. at a concentration of 0.1% by weight. .) Are preferably used.

  The aromatic polyester or aromatic polyester amide as the liquid crystalline resin (A) applicable to the present invention is particularly preferably at least one selected from the group of aromatic hydroxycarboxylic acids, aromatic hydroxyamines, and aromatic diamines. An aromatic polyester or aromatic polyester amide having the above compound as a constituent component.

More specifically,
(1) A polyester mainly composed of one or more aromatic hydroxycarboxylic acids and derivatives thereof;
(2) Mainly (a) one or more aromatic hydroxycarboxylic acids and derivatives thereof, and (b) one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and derivatives thereof (C) a polyester comprising at least one or more of aromatic diol, alicyclic diol, aliphatic diol, and derivatives thereof;
(3) Mainly (a) one or more aromatic hydroxycarboxylic acids and derivatives thereof, and (b) one or more aromatic hydroxyamines, aromatic diamines, and derivatives thereof; c) Polyesteramide comprising one or more of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and derivatives thereof;
(4) Mainly (a) one or more aromatic hydroxycarboxylic acids and derivatives thereof; and (b) one or more aromatic hydroxyamines, aromatic diamines and derivatives thereof; c) one or more of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and derivatives thereof; and (d) at least one of aromatic diol, alicyclic diol, aliphatic diol, and derivatives thereof. Or the polyesteramide which consists of 2 or more types is mentioned. Furthermore, you may use a molecular weight regulator together with said structural component as needed.

（Ｘ：アルキレン（Ｃ_１〜Ｃ_４）、アルキリデン、−Ｏ−、−ＳＯ−、−ＳＯ_２−、−Ｓ−、及び−ＣＯ−より選ばれる基である）

（Ｙ：−（ＣＨ_２）_ｎ−（ｎ＝１〜４）及び−Ｏ（ＣＨ_２）_ｎＯ−（ｎ＝１〜４）より選ばれる基である。） Preferable examples of the specific compound constituting the liquid crystalline resin (A) applicable to the present invention include aromatic hydroxycarboxylic acids such as p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, and 2,6-dihydroxy. Aromatic diols such as naphthalene, 1,4-dihydroxynaphthalene, 4,4′-dihydroxybiphenyl, hydroquinone, resorcin, a compound represented by the following general formula (I), and a compound represented by the following general formula (II) Aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 4,4′-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and compounds represented by the following general formula (III); p-aminophenol, p- Aromatic amines such as phenylenediamine are listed.

(X is a group selected from alkylene (C _{1 to} C ₄ ), alkylidene, —O—, —SO—, —SO ₂ —, —S—, and —CO—)

(Y is a group selected from — (CH ₂ ) _n — (n = 1 to 4) and —O (CH ₂ ) _n O— (n = 1 to 4).

The (A) liquid crystalline resin used in the present invention can be prepared by a known method using a direct polymerization method or a transesterification method from the above monomer compound (or a mixture of monomers). A combination method or a slurry polymerization method is used. The above compounds having ester-forming ability may be used for polymerization in the form as they are, or may be modified from a precursor to a derivative having ester-forming ability in the previous stage of polymerization. In the polymerization, various catalysts can be used. Typical examples include dialkyl tin oxide, diaryl tin oxide, titanium dioxide, alkoxy titanium silicates, titanium alcoholates, carboxylic acid alkalis and Examples include alkaline earth metal salts and Lewis acid salts such as BF ₃ . The amount of the catalyst used is generally about 0.001 to 1% by weight, particularly about 0.01 to 0.2% by weight, based on the total weight of the monomers. If the polymer produced by these polymerization methods is further necessary, the molecular weight can be increased by solid-phase polymerization by heating in a reduced pressure or an inert gas.

The melt viscosity of the (A) liquid crystalline resin obtained by the above method is not particularly limited. Generally, those having a melt viscosity at a molding temperature of 10 MPa or more and 600 MPa or less at a shear rate of 1000 sec ⁻¹ can be used. However, those having a very high viscosity are not preferable because the fluidity is extremely deteriorated. The (A) liquid crystalline resin may be a mixture of two or more liquid crystalline resins.

  In the liquid crystalline resin composition for a camera module of the present invention, the content of (A) liquid crystalline resin is 57 to 77% by mass. If the content of component (A) is 57% by mass or more, it is preferable for fluidity and suppression of raising of the surface of the molded body, and if the content of component (A) is 77% by mass or less, it is preferable for heat resistance. . Moreover, preferable content of (A) component is 60-75 mass%.

[(B) Inorganic filler]
(B) The inorganic filler comprises (B1) a fibrous filler having an average fiber diameter of 1.0 μm or less and an average fiber length of 5 to 50 μm, and (B2) a plate-like filler having an average particle diameter of 50 μm or less.

  (B1) The average fiber diameter of the fibrous filler is 1.0 μm or less, and the preferable average fiber diameter is 0.3 to 0.6 μm. When the average fiber diameter is 1.0 μm or less, the effect of suppressing napping on the surface of the molded body tends to be high. In the present specification, as the average fiber diameter, a value obtained by capturing a stereoscopic microscope image from a CCD camera into a PC and measuring the image by an image processing method is employed.

  Moreover, the average fiber length of (B1) fibrous filler is 5-50 micrometers, a preferable average fiber length is 5-30 micrometers, and a more preferable average fiber length is 7-30 micrometers. When the average fiber length is 5 μm or more, the mechanical strength and the deflection temperature under load necessary for the camera module are easily maintained, and when the average fiber length is 50 μm or less, the raising effect on the surface of the molded body is likely to increase. In this specification, as the average fiber length, a value obtained by taking a stereoscopic microscope image from a CCD camera into a PC and measuring by an image processing method using an image measuring machine is adopted.

  Any fiber can be used as long as it is a fibrous filler satisfying the above shape, but (B1) fibrous filler includes, for example, glass fiber, carbon fiber, asbestos fiber, silica fiber, silica Examples include inorganic fibrous materials such as alumina fibers, zirconia fibers, boron nitride fibers, silicon nitride fibers, boron fibers, potassium titanate fibers, and metal fibers such as fibers made of metals such as stainless steel, aluminum, titanium, copper, and brass. It is done. As the component (B1), two or more kinds of fibrous fillers may be used. In the present invention, potassium titanate fibers are preferably used as the component (B1).

  (B1) Content of a component is 5-15 mass% in the liquid crystalline composition for camera modules of this invention. When the content of the component (B1) is 5% by mass or more, the mechanical strength and the deflection temperature under load necessary for the camera module are easily secured, and when it is 15% by mass or less, the effect of suppressing the raising of the surface of the molded article is increased. Cheap. More preferably, the content is 7 to 13% by mass.

  (B2) The plate-like filler has an average particle size of 50 μm or less. When the average particle size is 50 μm or less, the effect of suppressing napping on the surface of the molded body tends to increase. The average particle size is preferably 10 to 20 μm. In this specification, the value measured by the laser diffraction / scattering particle size distribution measurement method is adopted as the average particle size.

  Any filler can be used as long as it satisfies the above shape, but examples of the (B2) plate filler include talc, mica, glass flakes, and various metal foils. . As the component (B2), two or more kinds may be used. In the present invention, talc and mica are preferably used as the component (B2), and talc is more preferably used.

  (B2) Content of a component is 6-18 mass% in the liquid crystalline composition for camera modules of this invention. When the content of the component (B2) is 6% by mass or more, blisters are hardly generated, and when it is 18% by mass or less, the effect of suppressing napping on the surface of the molded product tends to be high. The above-mentioned content is preferably 7 to 16% by mass.

  In addition, content of (B) inorganic filler (total amount of (B1) component and (B2) component) is 21-33 mass% in the resin composition for camera modules of this invention. When the content of the component (B) is 21% by mass or more, the dimensional stability is high, and when it is 33% by mass or less, the effect of suppressing napping on the surface of the molded body tends to be high. The preferable content is 21 to 30% by mass.

[(C) Copolymer]
The (C) copolymer is at least one selected from (C1) an olefin copolymer and (C2) a styrene copolymer. Mixing the component (C) with the liquid crystalline resin composition for a camera module contributes to suppressing raising of the surface of the molded product when the molded product obtained by molding the composition is subjected to ultrasonic cleaning.
The reason for suppressing the raising is not clarified, but it is considered that by adding a certain amount, the surface state of the molded body is changed, and the change contributes to suppressing the raising.

  (C1) The olefin copolymer is composed of an α-olefin and a glycidyl ester of an α, β-unsaturated acid.

The α-olefin is not particularly limited, and examples thereof include ethylene, propylene, and butene. Among them, ethylene is preferably used. The glycidyl ester of α, β-unsaturated acid is represented by the following general formula (IV). Examples of the glycidyl ester unit of α, β-unsaturated acid include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate and the like, and glycidyl methacrylate is particularly preferable.

  (C1) The content of α-olefin in the olefin copolymer is preferably 87 to 98% by mass, and the content of glycidyl ester of α, β-unsaturated acid is preferably 13 to 2% by mass.

  The (C1) olefin copolymer used in the present invention is a third component other than the above two components within the scope of the present invention, such as acrylonitrile, acrylate ester, methacrylate ester, α-methylstyrene, maleic anhydride, etc. You may contain 0-48 mass parts of 1 type, or 2 or more types of an olefin type unsaturated ester with respect to 100 mass parts of said 2 components.

  The olefin copolymer which is the component (C1) of the present invention can be easily prepared by a normal radical polymerization method using the monomers and radical polymerization catalysts of the respective components. More specifically, usually an α-olefin and an α, β-unsaturated glycidyl ester in the presence of a radical generator at 500 to 4000 atm and 100 to 300 ° C. in the presence of a suitable solvent or chain transfer agent. Or it can manufacture by the method of copolymerizing in absence. It can also be produced by a method in which an α-olefin, an α, β-unsaturated glycidyl ester and a radical generator are mixed and melt graft copolymerized in an extruder.

  The (C2) styrene copolymer is composed of styrenes and a glycidyl ester of an α, β-unsaturated acid. Since the glycidyl ester of α, β-unsaturated acid is the same as that described in the component (C1), the description thereof is omitted.

  Examples of styrenes include styrene, α-methylstyrene, brominated styrene, divinylbenzene and the like, and styrene is preferably used.

  The (C2) styrene-based copolymer used in the present invention may be a multi-component copolymer obtained by copolymerization using one or more other vinyl monomers as the third component in addition to the above two components. A suitable third component is one or more olefinic unsaturated esters such as acrylonitrile, acrylic acid ester, methacrylic acid ester, and maleic anhydride. A copolymer in which 40% by mass or less of a repeating unit derived from these is introduced into the (C2) styrene copolymer is preferred as the component (C2).

  (C2) In the styrene copolymer, the glycidyl ester content of the α, β-unsaturated acid is preferably 2 to 20% by mass, and the styrene content is preferably 80 to 98% by weight.

  (C2) The styrene copolymer can be prepared by a normal radical polymerization method using monomers and radical polymerization catalysts of each component. More specifically, styrenes and glycidyl esters of α, β-unsaturated acids are usually present in the presence of a radical generator at 500 to 4000 atmospheres at 100 to 300 ° C. in the presence of a suitable solvent or chain transfer agent or It can be produced by a method of copolymerization in the absence. It can also be produced by a method in which styrenes, a glycidyl ester of an α, β-unsaturated acid and a radical generator are mixed and subjected to melt graft copolymerization in an extruder.

  The (C) copolymer is preferably an (C1) olefin copolymer in terms of heat resistance, but the ratio of the (C1) component to the (C2) component is in accordance with the required characteristics as appropriate. Can be selected.

  The content of the (C) copolymer (the total amount of the (C1) component and the (C2) component) is 2 to 10% by mass in the camera module resin composition of the present invention. The content of the component (C) is 2% by mass or more from the viewpoint of suppressing raising of the surface of the molded body, and being 10% by mass or less obtains a good molded body without impairing fluidity. It is necessary for the reason. More preferably, the content is 2 to 7% by mass.

[(D) Carbon black]
The (D) carbon black used as an optional component in the present invention is not particularly limited as long as it is generally available for use in resin coloring. Usually, (D) carbon black contains a lump formed by agglomeration of primary particles, but the resin composition of the present invention is molded unless a large amount of lump having a size of 50 μm or more is contained. Many bumps (fine bumpy projections (fine irregularities) in which carbon black is aggregated) hardly occur on the surface of the molded body. When the content of particles having a lump particle diameter of 50 μm or more is 20 ppm or less, the effect of suppressing napping on the surface of the molded product tends to be high. A preferable content rate is 5 ppm or less.

  (D) As a compounding quantity of carbon black, in the liquid crystalline resin composition for camera modules, the range of 1-5 mass% is preferable. If the blending amount of carbon black is less than 1% by mass, the jet blackness of the resulting resin composition will be lowered, and the light-shielding property will be uneasy, and if it exceeds 5% by mass, it will be uneconomical. The possibility of occurrence of irregularities increases.

[Other ingredients]
The liquid crystalline resin composition for a camera module of the present invention includes other polymers, known substances generally added to synthetic resins, that is, antioxidants, ultraviolet absorbers, etc., as long as the effects of the present invention are not impaired. Stabilizers, antistatic agents, flame retardants, colorants such as dyes and pigments, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents, and powdered fillers such as silica and quartz powder. Depending on the case, it can be added appropriately.

[Preparation of liquid crystalline resin composition for camera module]
The preparation of the resin composition for a camera module of the present invention is not particularly limited. For example, the above components (A), (B), and (C) and optionally the above component (D) and other components are blended, and these are melt kneaded using a single screw or twin screw extruder. Thus, the liquid crystalline resin composition for the camera module is prepared.

[Liquid crystalline resin composition for camera modules]
The shape of the component (B) in the liquid crystalline resin composition for a camera module of the present invention is different from the shape of the component (B) before blending. The shape of the above component (B) is the shape before blending. If the shape before blending is as described above, a camera module component that is less prone to raising the surface can be obtained.

The liquid crystalline resin composition for a camera module of the present invention obtained as described above preferably has a melt viscosity of 50 Pa · sec or less. One of the characteristics of the liquid crystalline resin composition for camera modules of the present invention is that it has high fluidity and excellent moldability. Here, the melt viscosity is a value obtained by a measurement method based on ISO 11443 under conditions of a cylinder temperature of 350 ° C. and a shear rate of 1000 sec ⁻¹ .

  The liquid crystalline resin composition for a camera module of the present invention preferably has a deflection temperature under load of 200 ° C. or higher. The point which is excellent in heat resistance is also one of the characteristics of the liquid crystalline resin composition for camera modules of this invention. In addition, the value measured by the method based on ISO75-1 and 2 is employ | adopted for deflection temperature under load.

<Camera module parts and camera module>
A camera module component is manufactured using the liquid crystalline resin composition for a camera module. If the resin composition of this invention is used as a raw material, it will become difficult to raise the surface of the components for camera modules. Since the camera module component is ultrasonically cleaned, it is required that the surface is not easily raised even if the ultrasonic cleaning is performed. If the resin composition of the present invention is used, even if the ultrasonic cleaning of camera module parts is performed under stronger conditions, there will be no or almost no dropouts causing dust and the like. Accordingly, after the camera module parts are incorporated into the finished product, the dust generated by raising the surface of the camera module parts hardly affects the quality of the finished product.

  A camera module component formed by molding the liquid crystalline resin composition for a camera module of the present invention will be described. A cross section of a general camera module is schematically shown in FIG. As shown in FIG. 1, the camera module 1 includes a substrate 10, an optical element 11, a lead wire 12, a lens holder 13, a barrel 14, a lens 15, an IR filter 16, and a guide 17.

  The optical element 11 is disposed on the substrate 10, and the optical element 11 and the substrate 10 are electrically connected by a lead wiring 12.

  The guide 17 is disposed on the substrate 10, the lens holder 13 is disposed on the guide 17, and the guide 17 and the lens holder 13 cover the optical element 11. The lens holder 13 has an opening at the top, and a spiral groove is formed on the wall surface of the opening.

  The barrel 14 has a cylindrical shape, and the lens 15 is held inside the cylindrical shape so as to be substantially horizontal. In addition, a spiral convex portion is formed on the side wall of one end of the cylinder, and this spiral convex portion and the spiral groove portion formed on the opening wall surface of the lens holder 13 are screwed together, The barrel 14 is connected to the lens holder 13. An IR filter 16 is disposed at one end of the barrel 14 so as to close one end of the cylindrical barrel 14. As shown in FIG. 1, the IR filter 16 and the lens 15 are arranged substantially in parallel.

  In the camera module 1 as shown in FIG. 1, the lens holder 13 includes a magnetic force generated by a coil (not shown) wound around the lens holder 13 and a permanent magnet (not shown) arranged around the coil. The distance between the lens 15 and the optical element 11 changes by moving up and down on the guide 17 by the action of. The focus of the camera can be adjusted by adjusting this distance.

  In the camera module 1 as described above, the lens holder 13 and the barrel 14 which are parts for the camera module can be manufactured using the liquid crystalline resin composition for the camera module of the present invention as a raw material. A general liquid crystalline resin composition is not suitable as a raw material for producing these parts. When the lens holder 13 and the barrel 14 are manufactured using a general liquid crystalline resin composition as a raw material, the following problems occur.

  A molded body formed by molding a general liquid crystalline resin composition has a particularly high molecular orientation of the polymer at the surface portion, so that the surface of the molded body is easily raised, and this raising causes generation of small dust. If this small dust adheres to the lens 15 or the like, the performance of the camera module is degraded.

  Camera module parts such as the lens holder 13 and the barrel 14 are ultrasonically cleaned before being assembled into the camera module 1 for the purpose of removing dust and small dust on the surface. However, since the surface of a molded product formed by molding a general liquid crystalline resin composition is easily raised, the surface becomes fluffy when ultrasonically cleaned. Since such a problem arises, the molded object formed by shape | molding a liquid crystalline resin composition cannot usually be ultrasonically cleaned.

  The focus adjustment is performed on the guide 17 by the action of the magnetic force generated by the coil (not shown) wound around the lens holder 13 and the permanent magnet (not shown) arranged around the coil. It is done by moving up and down. At this time, since the surface of the molded body formed by molding a general liquid crystalline resin composition is likely to be raised as described above, the surface may be peeled off to produce a peeled material. There is a high possibility that the peeled material becomes small dust and adheres to the lens 15 or the like, thereby reducing the performance of the camera module.

  As described above, normally, when the liquid crystalline resin composition is used as a raw material for the lens holder 13 or the barrel 14, problems are likely to occur. However, when the liquid crystalline resin composition for a camera module of the present invention is used as a molded body, Since the surface state of the molded body has been improved so that even if the molded body is ultrasonically cleaned, there is almost no problem of raising, it can be preferably used as a raw material for the lens holder 13 and the barrel 14.

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

<Material>
Liquid crystalline resin (liquid crystalline polyester amide resin): Vectra (registered trademark) E950i (manufactured by Polyplastics Co., Ltd.)
Fibrous filler 1: Tismo N-102 manufactured by Otsuka Chemical Co., Ltd. (potassium titanate fiber, average fiber diameter 0.3 to 0.6 μm, average fiber length 10 to 20 μm)
Fibrous filler 2: PF70E001 (milled fiber, average fiber diameter 10 μm, average fiber length 70 μm) manufactured by Nittobo Co., Ltd.
Plate filler: Crown Talc PP (Talc, average particle diameter 12.8 μm, average aspect ratio 6) manufactured by Matsumura Sangyo Co., Ltd.
Olefin-based copolymer: Bond First 2C (ethylene-glycidyl methacrylate copolymer (containing 6% by mass of glycidyl methacrylate)) manufactured by Sumitomo Chemical Co., Ltd.
Carbon black: VULCAN XC305 manufactured by Cabot Japan Co., Ltd. (carbon black, average particle size of 20 nm, particle ratio of 50 μm or more is 20 ppm or less, granular)

<Manufacture of liquid crystalline resin composition for camera module>
The above components were melt-kneaded at a cylinder temperature of 350 ° C. using a twin screw extruder (TEX30α type manufactured by Nippon Steel Works) at the ratio shown in Table 1 to obtain a liquid crystalline resin composition pellet for a camera module. It was.

<Melt viscosity>
The melt viscosity of the liquid crystalline resin compositions for camera modules of Examples and Comparative Examples was measured using the pellets. Specifically, the apparent melt viscosity was measured in accordance with ISO 11443 under conditions of a cylinder temperature of 350 ° C. and a shear rate of 1000 sec ^{−1 using} a capillary rheometer (Capillograph 1D manufactured by Toyo Seiki: piston diameter 10 mm). For the measurement, an orifice having an inner diameter of 1 mm and a length of 20 mm was used. The results are shown in Table 1.

<Bending test>
The pellets of the example and the comparative example were molded under the following molding conditions using a molding machine (“SE100DU” manufactured by Sumitomo Heavy Industries, Ltd.) to prepare a bending test piece of 130 mm × 13 mm × 0.8 mm. Using this test piece, the bending strength and the flexural modulus were measured according to ASTM D790. The results are shown in Table 1.
〔Molding condition〕
Cylinder temperature: 350 ° C
Mold temperature: 90 ℃
Injection speed: 33mm / sec
Holding pressure: 50 MPa

<Load deflection temperature>
The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine (“SE100DU” manufactured by Sumitomo Heavy Industries, Ltd.) to obtain test specimens (4 mm × 10 mm × 80 mm). Thereafter, the deflection temperature under load was measured by a method based on ISO 75-1,2. Note that 1.8 MPa was used as the bending stress. The results are shown in Table 1.
〔Molding condition〕
Cylinder temperature: 350 ° C
Mold temperature: 80 ℃
Injection speed: 33mm / sec

<Evaluation of napping state (surface napping suppression effect) on the surface of the molded body>
The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine (“SE30DUZ” manufactured by Sumitomo Heavy Industries, Ltd.) to obtain a molded body of 12.5 mm × 120 mm × 0.8 mm. What cut | disconnected this molded object in half was used as a test piece.
〔Molding condition〕
Cylinder temperature: 350 ° C
Mold temperature: 90 ℃
Injection speed: 80mm / sec
[Evaluation]
The molded body cut in half was subjected to an ultrasonic cleaner (output 300 W, frequency 45 kHz) in water at room temperature for 3 minutes. Thereafter, the molded bodies before and after being subjected to an ultrasonic cleaning machine were compared, and the area (raised area) of the fluffed portion on the surface of the molded body was evaluated with an image measuring instrument (LUZEXFS manufactured by Nireco Corporation). The evaluation area was 750 mm ² (12.5 mm × 60 mm), and the ratio (%) of the raised area to the evaluation area was used as a result. The results are shown in Table 1.
The smaller the raising area, the higher the raising suppression effect.

<Number of blister samples>
The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine (“TR-100EH” manufactured by Sodick Co., Ltd.), and the molded body sample shown in FIG. 2 (size of the portion having the maximum area) : 50 mm × 5 mm × 0.2 mm). At that time, the gas vent was closed with grease to make it difficult to discharge gas, thereby making it easy to generate blisters. About 20 molded object samples, it was observed visually whether the blister was generated or not, and the number of blister generation samples was confirmed. The results are shown in Table 1.
〔Molding condition〕
Cylinder temperature: 350 ° C
Mold temperature: 140 ℃
Injection speed: 150mm / sec
Holding pressure: 75 MPa

<Mold shrinkage>
The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine (“S2000i 100B” manufactured by FANUC CORPORATION) to obtain test specimens (80 mm × 80 mm × 1 mmt). The dimensions of the test piece that had been allowed to stand for one day were measured at the flow direction measurement point and the perpendicular direction measurement point shown in FIG. From the measured specimen size and the die size at the location on the die corresponding to the measurement location, the molding shrinkage ratio is obtained according to the formula: (die size−test piece size) / die size × 100. It was. The mold dimensions were 79.981 mm in the flow direction and 79.994 mm in the perpendicular direction. The results are shown in Table 1.
〔Molding condition〕
Cylinder temperature: 350 ° C
Mold temperature: 90 ℃
Injection speed: 33mm / sec
Holding pressure: 50 MPa

  As is clear from the results shown in Table 1, it was confirmed that the molded body produced using the pellets of the example did not fluff even when ultrasonically cleaned. Moreover, it was confirmed that the molded body had a small number of blister generation samples and a positive molding shrinkage in the flow direction. From these results, the molded body formed by molding the pellets of the examples is greatly different in surface state from the molded body formed by molding the normal liquid crystalline resin composition pellets of comparative examples and the like, and the blister is It is hard to generate and it can be said that dimensional stability is high.

  Moreover, it was confirmed that the molded object manufactured using the pellet of an Example is excellent in heat resistance.

  Furthermore, it was confirmed that the molded object manufactured using the pellet of an Example has high mechanical strength. Therefore, by molding the pellets of the embodiment, it is possible to manufacture a camera module component that has high mechanical strength, and, for example, is less likely to break due to a driving impact.

DESCRIPTION OF SYMBOLS 1 Camera module 10 Board | substrate 11 Optical element 12 Lead wiring 13 Lens holder 14 Barrel 15 Lens 16 IR filter 17 Guide

Claims (3)

(A) liquid crystalline resin,
(B1) fibrous filler and (B2) plate filler (B) inorganic filler, and (C1) olefin copolymer and (C2) styrene copolymer at least one kind selected from (C) contains a copolymer,
The content of the component (A) is 57 to 77% by mass, the content of the component (B1) is 5 to 15% by mass, the content of the component (B2) is 6 to 18% by mass, and the content of the component (B) is 21-33 mass%, content of (C) component is 2-10 mass%,
The (B1) fibrous filler has an average fiber diameter of 1.0 μm or less and an average fiber length of 5 to 50 μm.
The (B2) plate-like filler has an average particle size of 50 μm or less,
The (B2) plate-like filler is talc,
The (C1) olefin copolymer is composed of an α-olefin and an α, β-unsaturated glycidyl ester,
The (C2) styrenic copolymer is a liquid crystalline resin composition for a camera module composed of styrenes and a glycidyl ester of an α, β-unsaturated acid.   2. The liquid crystalline resin composition for a camera module according to claim 1, wherein the (B2) plate-like filler has an average particle diameter of 10 to 20 μm.   Furthermore, (D) carbon black is contained and the content is 1-5 mass%, The liquid crystalline resin composition for camera modules of Claim 1 or 2.

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