KR102081231B1 - Liquid Crystal Resin Composition for Camera Module and Camera Module Using the Same - Google Patents

Abstract

Provided is a liquid crystalline resin composition for a camera module that is not easily brushed on the surface, curvature deformation is suppressed, mechanical strength is high, and is used to manufacture a component for a camera module excellent in heat resistance, and high fluidity at the time of melting.
The liquid crystalline resin composition for camera modules which concerns on this invention contains (A) liquid crystalline resin, (B) fibrous wollastonite, (C) epoxy group containing copolymer, and (D) plate-shaped filler, and content of (A) component The content of this 55-95.5 mass%, (B) component is 2.5-25 mass%, content of (C) component is 1.0-4.5 mass%, content of (D) component is 10-35 mass%, (B) component The sum total content of (D) component is 20-37.5 mass%.

Description

Liquid Crystal Resin Composition for Camera Module and Camera Module Using the Same

The present invention relates to a liquid crystal resin composition for a camera module and a camera module using the same.

Liquid crystalline resins typified by liquid crystalline polyester resins have excellent mechanical strength, heat resistance, chemical resistance, electrical properties, and the like, and have excellent dimensional stability, so they are widely used as high-performance engineering plastics. In recent years, liquid crystalline resins have been utilized in precision instrument parts by utilizing these characteristics.

In precision instruments, especially optics with lenses, small particles, dust, etc. affect the performance of the instrument. For example, in a part used for an optical device such as a camera module, when small particles, oil, and dust adhere to the lens, the optical characteristics of the camera module are significantly reduced. In order to prevent such deterioration of optical characteristics, the parts constituting the camera module (hereinafter, also referred to as "camera module components") are usually ultrasonically cleaned prior to assembly, so that small particles, oil, dust, etc. adhered to the surface are removed. Removed.

As described above, in the molded article formed by forming the liquid crystalline resin composition, since the molecular orientation of the polymer is particularly large at the surface portion, the surface of the molded article is likely to be peeled off. Is generated, and the raised portion of the fluff causes small particles to occur.

Therefore, when using a liquid crystalline resin composition as a raw material of a camera module component, the special liquid crystalline resin composition which does not raise the surface of a molded object is used even if the molded object is ultrasonically cleaned. As a special liquid crystalline resin composition, the liquid crystalline resin composition for camera modules containing liquid crystalline resin, specific talc, and carbon black is disclosed (refer patent document 1).

Japanese Patent Laid-Open No. 2009-242453

However, in the examination of the present inventors, the liquid crystalline resin composition for camera modules described in patent document 1 is insufficient in suppressing the raising of the surface of a molded object, and the liquid crystalline resin for camera modules for manufacturing the molded object which the surface of a molded object does not raise more easily. A composition is required.

Moreover, according to the examination of the present inventors, when shape | molding the conventional liquid crystalline resin composition for camera modules, and manufacturing molded objects, such as a lens holder, curvature distortion is large and it may cause a defect at the time of camera module assembly.

In recent years, cellular phones equipped with camera modules and carrying functions equivalent to non-contact type IC cards have become popular. Such mobile phones are placed close to the contactless reader when reading and writing information. At this time, since the mobile phone can collide with the non-contact reader with a strong force, a liquid crystalline resin composition for the camera module for producing a molded article having high mechanical strength is required so that the camera module in the mobile phone does not cause a problem. .

In addition, from the viewpoint of not easily causing problems during processing and use of the camera module, there is a need for a liquid crystal resin composition for a camera module for producing a molded article having excellent heat resistance.

In addition, the liquid crystalline resin composition for camera modules is required to have high fluidity at the time of melting from a moldability viewpoint.

This invention is made | formed in order to solve the said subject, The objective is used for manufacturing the camera module components which the surface does not raise easily, curvature deformation is suppressed, mechanical strength is high, and is excellent in heat resistance, and melts. It is providing the liquid crystalline resin composition for camera modules with high fluidity | liquidity in time.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched in order to solve the said subject. As a result, the inventors have found that the above problems can be solved by using a liquid crystal resin composition for a camera module containing a liquid crystal resin, fibrous wollastonite, an epoxy group-containing copolymer, and a plate-shaped filler in a specific ratio. Reached. More specifically, the present invention provides the following.

(1) (A) liquid crystalline resin,

    (B) fibrous wollastonite,

    (C) an epoxy group-containing copolymer, and

    (D) plate filler

Containing,

55-95.5 mass% of content of (A) component, 2.5-25 mass% of content of (B) component, 1.0-4.5 mass% of content of (C) component, and 10-35 mass of content of (D) component. Liquid crystal resin composition for camera modules whose total content of%, (B) component, and (D) component is 20-37.5 mass%.

(2) The composition as described in (1) whose (C) epoxy group containing copolymer is at least 1 sort (s) chosen from the group which consists of (C1) epoxy group containing olefin type copolymer and (C2) epoxy group containing styrene type copolymer.

(3) The component for camera modules which consists of a composition as described in (1) or (2).

(4) A camera module comprising the component described in (3).

The liquid crystalline resin composition for camera modules of the present invention has high fluidity at the time of melting, and when the composition for the camera module is manufactured using this composition as a raw material, the surface is not easily brushed, bending deformation is suppressed, mechanical strength is high, The camera module parts excellent in heat resistance can be obtained.

1 is a cross-sectional view schematically showing a general camera module.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described. This invention is not limited to the following embodiment.

<Liquid crystalline resin composition for camera module>

The liquid crystalline resin composition for camera modules of this invention contains (A) liquid crystalline resin, (B) fibrous wollastonite, (C) epoxy group containing copolymer, and (D) plate-shaped filler.

[(A) Liquid Crystalline Resin]

(A) liquid crystalline resin used by this invention refers to the melt-processable polymer which has the property which can form an optically anisotropic molten phase. The property of the anisotropic molten phase can be confirmed by the conventional polarization test method using a rectangular polarizer. More specifically, confirmation of an anisotropic molten phase can be made by using a Leitz polarization microscope and observing the molten sample placed in the Leitz hot stage by 40 times magnification under nitrogen atmosphere. When the liquid crystalline polymer which can be applied to the present invention is inspected between orthogonal polarizers, polarized light is usually transmitted even in the state of melting stop, and optically anisotropy is exhibited.

It does not specifically limit as a kind of above-mentioned (A) liquid crystalline resin, It is preferable that they are aromatic polyester and / or aromatic polyesteramide. Moreover, the polyester which partially contains aromatic polyester and / or aromatic polyesteramide in the same molecular chain is also in the range. (A) As liquid crystalline resin, when it melt | dissolves in pentafluorophenol at the density | concentration of 0.1 mass% at 60 degreeC, Algebraic viscosity (IV) of at least about 2.0 dl / g, More preferably, 2.0-10.0 dl / g is preferable. Is preferably used.

The aromatic polyester or the aromatic polyester amide as (A) liquid crystalline resin applicable to the present invention is particularly preferably at least selected from the group consisting of aromatic hydroxycarboxylic acid, aromatic hydroxyamine, and aromatic diamine. An aromatic polyester or aromatic polyesteramide which has a repeating unit derived from 1 type of compound as a structural component.

More specifically,

(1) Polyester mainly consisting of repeating units derived from 1 type, or 2 or more types of aromatic hydroxycarboxylic acid and its derivative (s);

(2) repeating units mainly derived from one or two or more of (a) aromatic hydroxycarboxylic acids and derivatives thereof, and (b) one of aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and derivatives thereof, or Polyester consisting of the repeating unit derived from 2 or more types, and (c) repeating units derived from at least 1 sort (s) or 2 or more types of aromatic diol, alicyclic diol, aliphatic diol, and derivatives thereof;

(3) repeating units mainly derived from one or two or more of (a) aromatic hydroxycarboxylic acids and derivatives thereof, and (b) one or two or more of aromatic hydroxyamines, aromatic diamines, and derivatives thereof. Polyesteramide which consists of a repeating unit derived from 1 type, and the repeating unit derived from 1 type, or 2 or more types of (c) aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and these derivatives;

(4) repeating units mainly derived from one or two or more of (a) aromatic hydroxycarboxylic acids and derivatives thereof, and (b) one or two or more of aromatic hydroxyamines, aromatic diamines, and derivatives thereof. Repeating units derived from (c), (c) aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and repeating units derived from one or two or more of these derivatives, and (d) aromatic diols, alicyclic diols, and aliphatic diols. And polyesteramides composed of repeating units derived from at least one or two or more of these derivatives. Moreover, a molecular weight modifier can be used together as said structural component as needed.

As a preferable example of the specific compound which comprises (A) liquid crystalline resin applicable to this invention, aromatic hydroxycarboxylic acids, such as p-hydroxy benzoic acid and 6-hydroxy-2- naphthoic acid, 2, 6-di Represented by hydroxynaphthalene, 1,4-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl, hydroquinone, resorcin, the compound represented by the following general formula (I), and the following general formula (II) Aromatic diols such as compound to be used; Aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 4,4'-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and a compound represented by the following general formula (III); Aromatic amines, such as p-aminophenol and p-phenylenediamine, are mentioned.

(X is a group selected from alkylene (C ₁ to C ₄ ), alkylidene, -O-, -SO-, -SO _2- , -S-, and -CO-)

_{(Y: - (CH 2)} n - is a group selected from a (n = 1 ~ 4) and _{-O (CH 2) n O- (} n = 1 ~ 4).)

Preparation of (A) liquid crystalline resin used for this invention can be performed from the said monomer compound (or mixture of monomers) by a well-known method using the direct polymerization method or the transesterification method, Usually, melt polymerization method, Slurry polymerization and the like. The compounds having an ester forming ability can be used for polymerization in the form as it is, and may be modified with a derivative having the ester forming ability from a precursor in the pre-polymerization step. When polymerizing these, various catalysts can be used, and typical examples thereof include dialkyltin oxides, diaryltin oxides, titanium dioxide, alkoxytitanium silicates, titanium alcoholates, alkali and alkaline earth metal salts of carboxylic acids, and BF _3. Lewis salts, such as these, etc. are mentioned. The amount of the catalyst generally used is preferably about 0.001 to 1% by mass, particularly about 0.01 to 0.2% by mass, based on the total mass of the monomers. Polymers produced by these polymerization methods can further increase the molecular weight by solid phase polymerization heating in a reduced pressure or inert gas, if necessary.

The melt viscosity of (A) liquid crystalline resin obtained by the above method is not specifically limited. In general, the melt viscosity at the molding temperature may be from 10 MPa to 600 MPa at a shear rate of 1000 sec ⁻¹ . However, it is not preferable that the very high viscosity itself is very poor in fluidity. The liquid crystalline resin (A) may be a mixture of two or more liquid crystalline resins.

In the liquid crystalline resin composition for camera modules of this invention, content of (A) liquid crystalline resin is 55-95.5 mass%. When content of (A) component is 55 mass% or more, it is preferable from the reason of fluidity | liquidity and suppression of raising of the surface of a molded object, and when content of (A) component is 95.5 mass% or less, it is preferable from the reason of heat resistance. Moreover, preferable content of (A) component is 60-80 mass%, and more preferable content of (A) component is 62-70 mass%.

[(B) Fibrous wollastonite]

As used herein, (B) fibrous wollastonite refers to wollastonite having an aspect ratio, that is, a value of average fiber length / average fiber diameter of 8 or more. The aspect ratio is preferably 10 to 25, more preferably 15 to 20 from the viewpoint of the effect of suppressing the raising of the surface of the molded body. In the present specification, wollastonite having an aspect ratio of less than 8 is called granular wollastonite.

(B) Fibrous wollastonite is not specifically limited, For example, a well-known fibrous wollastonite can be used. (B) Fibrous wollastonite may be used alone, or may be used in combination of two or more kinds of different aspect ratios, average fiber lengths, and average fiber diameters.

The average fiber diameter of the (B) fibrous wollastonite is preferably 3.0 to 50 µm, and more preferably 4.5 to 40 µm. If the average fiber diameter is 3.0 µm or more, the mechanical strength and load bending temperature required as the camera module are easily secured. When the said average fiber diameter is 50 micrometers or less, the napping inhibitory effect on the surface of a molded object tends to become high. In this specification, as an average fiber diameter, a stereomicroscope image is transferred from a CCD camera to a PC, and the value measured by the image processing method using the image measuring machine is employ | adopted.

The average fiber length of the (B) fibrous wollastonite is preferably 30 to 800 µm, and more preferably 50 to 600 µm. If the average fiber length is 30 µm or more, the mechanical strength and load bending temperature required as the camera module are easily secured. If the said average fiber length is 800 micrometers or less, the napping inhibitory effect on the surface of a molded object will become high easily. In this specification, as an average fiber length, a stereomicroscope image is moved from a CCD camera to a PC, and the value measured by the image processing method using the image measuring instrument is employ | adopted.

Content of (B) component is 2.5-25 mass% in the liquid crystalline composition for camera modules of this invention. If content of (B) component is 2.5 mass% or more, the mechanical strength and load bending temperature required as a camera module will be ensured easily. If content of (B) component is 25 mass% or less, the fluidity | liquidity at the time of melting of a composition will improve easily, the raising effect of suppressing the raising of the surface of a molded object will become easy, and the curvature distortion suppression effect of a molded object will become high easily. More preferable said content is 5-20 mass%.

[(C) Epoxy Group-Containing Copolymer]

(C) An epoxy group containing copolymer can be used individually by 1 type or in combination of 2 or more types. It does not specifically limit as (C) epoxy group containing copolymer, For example, at least 1 sort (s) chosen from the group which consists of (C1) epoxy group containing olefin type copolymer and (C2) epoxy group containing styrene type copolymer is mentioned. . Mixing (C) component with the liquid crystalline resin composition for camera modules contributes to suppressing the raising of the surface of a molded object, when ultrasonically cleaning the molded object formed by shape | molding the said composition.

The reason for suppressing napping is not clear, but it can be considered that by mixing a certain amount, the surface state of the molded body is changed, and the change contributes to suppressing napping.

Examples of the (C1) epoxy group-containing olefin copolymer include copolymers composed of repeating units derived from α-olefins and repeating units derived from glycidyl esters of α, β-unsaturated acids.

(alpha) -olefin is not specifically limited, For example, ethylene, propylene, butene, etc. are mentioned, Ethylene is used preferably among these. Glycidyl ester of (alpha), (beta)-unsaturated acid is represented by following General formula (IV). As glycidyl ester of (alpha), (beta)-unsaturated acid, glycidyl ester of acrylic acid, glycidyl ester of methacrylic acid, glycidyl ester of acrylate, glycidyl ester of itaconic acid, etc. are mentioned, for example, Especially, methacrylic acid glycidyl ester is preferable.

(C1) In the epoxy group-containing olefin copolymer, the content of the repeating unit derived from the α-olefin is 87 to 98 mass%, and the content of the repeating unit derived from the α, β-unsaturated acid glycidyl ester is 13 to It is preferable that it is 2 mass%.

The (C1) epoxy group-containing olefin copolymer used in the present invention is an acrylonitrile, an acrylic acid ester, a methacrylic acid ester, α-methylstyrene, anhydrous as a third component in addition to the above two components within the range of not impairing the present invention. 0-48 mass parts of repeating units derived from 1 type, or 2 or more types of olefinic unsaturated ester, such as maleic acid, can be contained with respect to 100 mass parts of said two components.

The epoxy group containing olefin copolymer which is (C1) component of this invention can be easily prepared by the normal radical polymerization method using the monomer corresponding to each component, and a radical polymerization catalyst. More specifically, glycidyl esters of α-olefins and α, β-unsaturated acids are usually in the presence of a radical generating agent at 500 to 4000 atmospheres at 100 to 300 ° C. in the presence or absence of a suitable solvent or chain transfer agent. It can manufacture by the method of copolymerizing. Moreover, it can also manufacture by the method of mixing the glycidyl ester of a (alpha) -olefin, (alpha), (beta)-unsaturated acid, and a radical generator, and melt-grafting copolymerization in an extruder.

As an epoxy-group-containing styrene copolymer of (C2), the copolymer comprised from the repeating unit derived from styrene and the repeating unit derived from glycidyl ester of (alpha), (beta)-unsaturated acid is mentioned, for example. Since glycidyl ester of (alpha), (beta)-unsaturated acid is the same as what was demonstrated by (C1) component, description is abbreviate | omitted.

Styrene, (alpha) -methylstyrene, brominated styrene, divinylbenzene, etc. are mentioned as styrene, Styrene is used preferably.

The (C2) epoxy group-containing styrene copolymer used in the present invention may be a multi-component copolymer containing a repeating unit derived from one or two or more kinds of other vinyl monomers as a third component in addition to the two components. As a 3rd component, what is suitable is a repeating unit derived from 1 type, or 2 or more types of olefinic unsaturated esters, such as an acrylonitrile, acrylic acid ester, methacrylic acid ester, and maleic anhydride. An epoxy group-containing styrene copolymer containing 40% by mass or less of these repeating units in the copolymer is preferable as the component (C2).

(C2) In the epoxy group-containing styrene copolymer, the content of the repeating unit derived from the glycidyl ester of the α, β-unsaturated acid is 2 to 20% by mass, and the content of the repeating unit derived from the styrene is 80 to It is preferable that it is 98 mass%.

The epoxy group-containing styrene copolymer (C2) can be prepared by a normal radical polymerization method using a monomer and a radical polymerization catalyst corresponding to each component. More specifically, glycidyl esters of styrene and α, β-unsaturated acid are usually used in the presence of a radical generating agent at 500 to 4000 atmospheres at 100 to 300 ° C. in the presence or absence of a suitable solvent or chain transfer agent. It can manufacture by the method of copolymerizing. Moreover, it can also manufacture by the method of mixing styrene, the glycidyl ester of an (alpha), (beta)-unsaturated acid, and a radical generator, and melt-grafting copolymerization in an extruder.

As the (C) epoxy group-containing copolymer, the (C1) epoxy group-containing olefin copolymer is preferable in terms of heat resistance. When using together (C1) component and (C2) component, the ratio of these components can be suitably selected according to the characteristic requested | required.

Content of the (C) epoxy group containing copolymer is 1.0-4.5 mass% in the resin composition for camera modules of this invention. The content of (C) component of 1.0 mass% or more is necessary in terms of suppressing raising of the surface of a molded object, and the thing of 4.5 mass% or less is necessary for the reason of obtaining a favorable molded object, without impairing fluidity. More preferable said content is 2.0-4.0 mass%.

[(D) Plate Filler]

It is preferable that (D) plate-shaped filler is 20-50 micrometers in average particle diameter. If the average particle diameter is 20 µm or more, the mechanical strength and load bending temperature required as the camera module are easily ensured, and the effect of suppressing warpage deformation of the molded body is likely to be increased. If the said average particle diameter is 50 micrometers or less, the brushing suppression effect of the surface of a molded object will become high easily. Preferable said average particle diameter is 23-30 micrometers. In this specification, the value measured by the laser diffraction / scattering particle size distribution measuring method is employ | adopted as an average particle diameter.

(D) As a plate-shaped filler, it does not specifically limit, For example, mica, talc, glass flakes, graphite, various metal foils (for example, aluminum foil, iron foil, copper foil), etc. are mentioned. Two or more types can be used as (D) component. In this invention, it is preferable to use mica and talc as (D) component, and it is more preferable to use mica.

Content of (D) component is 10-35 mass% in the liquid crystalline composition for camera modules of this invention. If content of (D) component is 10 mass% or more, the mechanical strength and load bending temperature required as a camera module will be ensured easily, and the bending deformation suppression effect of a molded object will become high easily. When content of (D) component is 35 mass% or less, the raising effect of suppressing the surface of a molded object tends to become high. Preferable said content is 15-30 mass%.

In addition, the total content of (B) component and (D) component is 20-37.5 mass% in the liquid crystalline composition for camera modules of this invention, Preferably it is 25-35 mass%. If the said total content is 20 mass% or more, the mechanical strength and load bending temperature which are required as a camera module will be ensured easily. When the said total content is 37.5 mass% or less, the fluidity | liquidity at the time of melting of a composition will improve easily, the napping inhibitory effect on the surface of a molded object will become high easily, and the impact resistance of a molded object will become easy.

[(E) Carbon Black]

The (E) 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, the carbon black (E) includes agglomerates formed by agglomeration of primary particles, but is formed by molding the resin composition of the present invention unless a large amount of agglomerates having a size of 50 μm or more is included. Many millet bumps (fine millet-like protrusions (fine irregularities) in which carbon black is agglomerated) are hardly generated on the surface of the molded body. If the content rate of the particle | grains whose lump form particle diameter is 50 micrometers or more is 20 ppm or less, the napping inhibitory effect of the surface of a molded object will become high easily. Preferable content rate is 5 ppm or less.

As a compounding quantity of (E) carbon black, the range of 0.5-5 mass% is preferable in the liquid crystalline resin composition for camera modules. When the compounding quantity of carbon black is 0.5 mass% or more, the black-blackness of the resin composition obtained does not fall easily, and light-shielding property does not become unstable easily. If the blending amount of carbon black is 5% by mass or less, it is not economical, and millet projections are not easily generated.

[Other Ingredients]

In the liquid crystalline resin composition for camera modules of the present invention, stabilizers such as other polymers, other fillers, known materials generally added to synthetic resins, that is, antioxidants and ultraviolet absorbers, within a range that does not impair the effects of the present invention, Antistatic agents, flame retardants, coloring agents such as dyes and pigments, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents and the like can also be appropriately added depending on the required performance.

Other filler means (B) fibrous wollastonite, (D) plate filler, and (E) filler other than carbon black, For example, wollastonite other than (B) fibrous wollastonite, such as wollastonite whose aspect ratio is less than 8; (B) fibrous fillers other than fibrous wollastonite, such as glass fiber; Granular fillers, such as a silica, are mentioned.

[Preparation of liquid crystalline resin composition for camera module]

Preparation of the resin composition for camera modules of this invention is not specifically limited. For example, the said liquid crystal resin composition for camera modules is prepared by mix | blending said (A), (B), (C), and (D) components, and melt-kneading these using a single-axis or twin-screw extruder. do.

[LCD crystalline resin composition for camera module]

The shape of (B) component in the liquid crystalline resin composition for camera modules of this invention differs from the shape of (B) component before mix | blending. The shape of (B) component mentioned above is a shape before mix | blending. If the shape before mixing | blending is as mentioned above, the component for camera modules which a surface does not raise easily can be obtained.

Similarly, the shape of (D) component in the liquid crystalline resin composition for camera modules of this invention differs from the shape of (D) component before mix | blending. The shape of (D) component mentioned above is a shape before mix | blending. If the shape before mixing | blending is as mentioned above, the component for camera modules with which curvature distortion was suppressed can be obtained.

It is preferable that melt viscosity of the liquid crystalline resin composition for camera modules of this invention obtained as mentioned above is less than 50 Pa.sec. It is one of the characteristics of the liquid crystalline resin composition for camera modules of this invention that the fluidity | liquidity at the time of melting is high, and is excellent in moldability. In this specification, as a melt viscosity, the value obtained by the measuring method based on ISO11443 is employ | adopted on the conditions of the cylinder temperature 10-20 degreeC higher than melting | fusing point of liquid crystalline resin, and the shear rate 1000 sec ^-1 .

It is preferable that load bending temperature of the liquid crystalline resin composition for camera modules of this invention is 240 degreeC or more. The point which is excellent in heat resistance is one of the characteristics of the liquid crystalline resin composition for camera modules of this invention. The load bending temperature adopts the value measured by the method based on ISO 75-1,2.

<Parts for Camera Module and Camera Module>

The camera module component is manufactured using the said liquid crystalline resin composition for camera modules. When the resin composition of this invention is used as a raw material, the surface of the camera module component does not raise easily. Since the components for the camera module are ultrasonically cleaned, the surface of the camera module should not be easily brushed even when ultrasonically cleaned. When the resin composition of this invention is used, even if ultrasonic cleaning of the components for camera modules is performed on stronger conditions, the falling-off thing which causes dust etc. does not generate | occur | produce or hardly generate | occur | produce. Therefore, after the camera module component is joined to the finished product, the dust generated by raising the surface of such a camera module component rarely affects the quality of the finished product.

The component for camera modules formed by shape | molding the liquid crystalline resin composition for camera modules of this invention is demonstrated. The cross section of the general camera module is typically 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, and a lens 15. ), An IR filter 16, a guide 17.

The optical element 11 is arrange | positioned on the board | substrate 10, and is electrically connected with the lead wiring 12 between the optical element 11 and the board | substrate 10. FIG.

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 surround the optical element 11. . An opening is formed in the top of the lens holder 13, and a spiral groove is formed in the opening wall.

The barrel 14 is cylindrical, and is maintained so that the lens 15 is substantially horizontal in the cylindrical interior. In addition, a spiral convex portion is formed on the side wall of one end of the cylinder. The spiral convex portion and the spiral groove portion formed on the opening wall surface of the lens holder 13 are combined to form a barrel 14 with a lens holder ( 13). In addition, the 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 almost in parallel.

In the camera module 1 shown in FIG. 1, the lens holder 13 has 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. By moving up and down the guide 17, the distance between the lens 15 and the optical element 11 changes. By adjusting this distance, the focus of the camera can be adjusted.

In the camera module 1 as described above, the lens holder 13 and / or barrel 14, which is a component for the camera module, can be manufactured using the liquid crystal resin composition for the camera module of the present invention as a raw material. The general liquid crystalline resin composition is not suitable as a raw material for producing such a part. When the lens holder 13 and / or the barrel 14 are manufactured using a general liquid crystalline resin composition as a raw material, the following problems arise.

In a molded article formed by molding a general liquid crystalline resin composition, the surface of the molded article is easily brushed because the molecular orientation of the polymer is particularly large at the surface portion, and such raising causes small particles to occur. If such small particles adhere to the lens 15 or the like, the performance of the camera module is degraded.

Components for the camera module, such as the lens holder 13 and the barrel 14, are ultrasonically cleaned before being joined to the camera module 1 for the purpose of removing surface dirt and small particles. However, since the surface of the molded article formed by molding a general liquid crystalline resin composition is likely to be brushed, the surface is fluffed when ultrasonically cleaned. Normally, the molded object formed by shape | molding a liquid crystalline resin composition cannot be ultrasonically cleaned by such a problem.

The above focus adjustment is performed by the lens holder 13 by the action of 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. 17) It is done by raising and lowering the image. At this time, the molded article formed by molding the general liquid crystalline resin composition, since the surface is easily brushed, as described above, there is a possibility that the surface is peeled off, the peeling material may be generated. Such peeling material becomes small dust, adheres to the lens 15, etc., and is likely to degrade the performance of a camera module.

As mentioned above, when a liquid crystalline resin composition is normally used as a raw material of the lens holder 13 and / or the barrel 14, defects will occur easily, but when the liquid crystalline resin composition for camera modules of this invention is made into a molded object, Since the surface state of a molded object improves to such an extent that a brushing problem hardly arises even if such a molded object is ultrasonically cleaned, it can be used suitably as a raw material of the lens holder 13 and / or the barrel 14.

When using the liquid crystal resin composition for camera modules of this invention for the lens holder 13, as a material of the guide 17, things other than the liquid crystal resin composition for camera modules of this invention are mentioned, Specifically, nylon Etc. can be mentioned.

[ Example ]

Although an Example is given to the following and this invention is demonstrated in more detail, this invention is not limited only to these Examples.

<Liquid crystalline resin>

Liquid crystalline polyesteramide resin

After putting the next raw material into the polymerization vessel, the temperature of the reaction system was raised to 140 ° C and reacted at 140 ° C for 1 hour. Thereafter, the mixture was further heated to 340 ° C for 4.5 hours, and thereafter reduced to 10 Torr (ie, 1330 Pa) over 15 minutes, and melt polymerization was carried out while distilling acetic acid, excess acetic anhydride, and other low specific fractions. Was carried out. After the stirring torque reached a predetermined value, nitrogen was introduced to the pressurized state from the reduced pressure state through the normal pressure, the polymer was discharged from the lower portion of the polymerization vessel, and the strands were pelletized to obtain pellets. The obtained pellets were heat-treated at 300 ° C. for 2 hours under a stream of nitrogen to obtain the desired polymer. Melting | fusing point of the obtained polymer was 334 degreeC, and melt viscosity was 14.0 Pa.s. The melt viscosity of the polymer was measured in the same manner as the measuring method of melt viscosity described later.

(I) 4-hydroxybenzoic acid; 188.4 g (60 mol%)

(II) 2-hydroxy-6-naphthoic acid; 21.4 g (5 mol%)

(III) terephthalic acid; 66.8 g (17.7 mole%)

(IV) 4,4'-dihydroxybiphenyl; 52.2 g (12.3 mol%)

(V) 4-acetoxyaminophenol; 17.2 g (5 mol%)

Metal catalysts (potassium acetate catalyst); 15 mg

Acylating agents (anhydrous acetic acid); 226.2 g

<Materials other than liquid crystalline resin>

Fibrous wollastonite: NYGLOS 8 (product of NYCO Materials, aspect ratio 17, average fiber length 136 μm, average fiber diameter 8 μm)

Granular wollastonite: NYAD 325 (product of NYCO Materials, aspect ratio 5, average fiber length 50㎛, average fiber diameter 5㎛)

Glass fiber: PF70E-001 (Nittobo Co., Ltd., Mild fiber, Average fiber diameter 10㎛, Average fiber length 70㎛)

Epoxy group-containing olefin copolymer: Bond Fast 2C (Sumitomo Chemical Co., Ltd. product, ethylene-glycidyl methacrylate copolymer, glycidyl methacrylate content 6% by mass)

Epoxy-free copolymer: Toughtec M1913 (manufactured by Asahi Kasei Co., Ltd., maleic anhydride modified hydrogenated styrene-ethylene-butadiene-styrene block copolymer)

Plate filler 1: AB-25S (manufactured by Yamaguchi Mica Co., Ltd., mica, average particle size 24㎛)

Plate Filler 2: Crown Talc PP (Matsumura Industries Co., Ltd., talc, average particle diameter 12.8 μm, average aspect ratio 6)

Carbon black: VULCAN XC305 (Cabot Japan Co., Ltd., 20nm average particle diameter, 20ppm particle size or more)

<Production of Liquid Crystal Resin Composition for Camera Module>

The said component was melt-kneaded at the cylinder temperature of 350 degreeC using the twin screw extruder (TEX30alpha type made by Nippon Steel Co., Ltd.) in the ratio shown in Table 1 or Table 2, and the liquid crystal resin composition pellets for camera modules were obtained.

<Melt viscosity>

Melt viscosity of the liquid crystalline resin composition for camera modules of Examples and Comparative Examples was measured using the pellets. Specifically, the apparent melt viscosity under the conditions of a cylinder temperature of 350 ° C. and a shear rate of 1000 sec ⁻¹ was measured using a capillary rheometer (Capillary Graph 1D manufactured by Toyo Seiki Co., Ltd .: piston diameter 10 mm) in accordance with ISO 11443. It was. An orifice with an internal diameter of 1 mm and a length of 20 mm was used for the measurement. The results are shown in Table 1 and Table 2.

<Load Bend Temperature>

The pellet of an Example and a comparative example was shape | molded using the molding machine ("SE100DU" by Sumitomo Heavy Industries, Ltd.) on the following molding conditions, and the test piece for measurement (4mm x 10mm x 80mm) was obtained. Using this test piece, load bending temperature was measured by the method based on ISO75-1,2. As the bending stress, 1.8 MPa was used. The results are shown in Table 1 and Table 2.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 80 ℃

Back pressure: 2.0MPa

Injection Speed: 33mm / sec

<Bending test>

The pellet of the Example and the comparative example was shape | molded using the molding machine ("SE100DU" by Sumitomo Heavy Industries, Ltd.), and the bending test piece of 130 mm x 13 mm x 0.8 mm was produced. Using this test piece, flexural strength, flexural modulus, and fracture strain were measured in accordance with ASTM D790. The results are shown in Table 1 and Table 2.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 90 ℃

Injection Speed: 33mm / sec

Holding pressure: 50MPa

<Charpy impact test>

The pellet of the Example and the comparative example was shape | molded using the molding machine ("SE100DU" by Sumitomo Heavy Industries, Ltd.) by the following test conditions on the measurement test piece (4 mm x 10 mm x 80 mm). Using this test piece, Charpy impact strength was measured by the method according to ISO 179-1. The results are shown in Table 1 and Table 2.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 80 ℃

Back pressure: 2.0MPa

Injection Speed: 33mm / sec

<Plan view>

The pellet of an Example and a comparative example was shape | molded using the molding machine ("SE-100DU" by Sumitomo Heavy Industries, Ltd.), and five flat test pieces of 80 mmH80mmH1mm were produced. The first flat plate specimen was placed on a horizontal plane, and the height from the horizontal plane was measured at nine places on the flat plate specimen using a CNC image measuring machine (model: QVBHU404-PRO1F) manufactured by Mitsutoyo Co., Ltd. The average height was computed from the obtained measurement. The position where the height was measured is the vertex of each square and the midpoint of the square of the square when a square having a side of 74 mm is placed on the principal plane of the flat test piece so that the distance from each side of the principal plane is 3 mm. , And the positions corresponding to the intersections of the two diagonals of this square. The height from the horizontal plane was the same as the average height, and the plane parallel to the horizontal plane was used as the reference plane. Of the heights measured at the nine places, the maximum height and the minimum height from the reference plane were selected, and the difference between them was calculated. In the same manner, the above difference was also calculated for the other four flat plate specimens, and the five values obtained were averaged to be values of the plan view. The results are shown in Table 1 and Table 2.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 80 ℃

Injection Speed: 33mm / sec

Holding pressure: 60MPa

<Number of dust occurrence>

The pellet of an Example and a comparative example was shape | molded using the molding machine ("SE30DUZ" by Sumitomo Heavy Industries, Ltd.) on the following molding conditions, and the molded object of 12.5 mm 120 120 mm 0.8 0.8 mm was obtained. This molded body was used as a test piece.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 90 ℃

Injection speed: 80mm / sec

〔evaluation〕

The test piece was suspended in an ultrasonic cleaner (output 300 W, frequency 45 kHz) in water at room temperature for 3 minutes. Then, the particle count (RION Co., Ltd. product, liquid fine particle counter KL-11A (PARTICLECOUNTER)) measured the particle count of 2 micrometers or more which exists in the said water, and evaluated as dust generation water. The results are shown in Table 1 and Table 2.

As is evident from the results shown in Tables 1 and 2, it was confirmed that the molded article produced using the pellets of the examples had less dust generation even when ultrasonic cleaning. Moreover, the numerical value of the top view of the said molded object was small. From these results, it can be said that the molded body formed by molding the pellets of the examples is significantly different in surface state from the molded body formed by molding pellets of ordinary liquid crystalline resin composition such as Comparative Examples, and curvature deformation is suppressed.

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

Moreover, it was confirmed that the molded object manufactured using the pellet of an Example has high mechanical strength, such as bending strength and impact resistance. Therefore, by molding the pellets of the embodiment, the mechanical strength is high, and specifically, the parts for the camera module, which are not easily broken, for example, by the impact at the time of a collision with a non-contact reader or the like or the impact of driving, are produced. can do.

Moreover, it was confirmed that the pellet of an Example has the high fluidity | liquidity at the time of melt, and is excellent in moldability.

1 camera module
10 boards
11 optical elements
12 lead wiring
13 lens holder
14 barrels
15 lenses
16 IR Filter
17 Guide

Claims (4)

(A) liquid crystalline resin,
(B) fibrous wollastonite,
(C) an epoxy group-containing copolymer, and
(D) plate-shaped filler,
Containing,
62-70 mass% of content of (A) component, 2.5-25 mass% of content of (B) component, 1.0-4.5 mass% of content of (C) component, and 10-30 mass of content of (D) component Liquid crystal resin composition for camera modules whose total content of%, (B) component, and (D) component is 20-35 mass%. The method of claim 1,
The said (C) epoxy group containing copolymer is a composition which is at least 1 sort (s) chosen from the group which consists of a (C1) epoxy group containing olefin type copolymer and (C2) epoxy group containing styrene type copolymer. The camera module component which consists of a composition of Claim 1 or 2. The camera module provided with the component of Claim 3.

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