KR102062267B1 - Liquid crystal resin composition for camera modules - Google Patents

Abstract

The present invention provides a liquid crystalline resin composition for a camera module for producing a camera module component for which the surface of the molded body is not easily raised, the mechanical strength is high, the blister does not easily occur, the dimensional stability is high, and the bending deformation is suppressed. to provide.
This invention contains (A) liquid crystalline resin, (B) plate-shaped filler, and at least 1 sort (C) copolymer chosen from (C1) olefin copolymer and (C2) styrene copolymer, (A The content of the component is 64 to 78 mass%, the content of the component (B) is 20 to 30 mass%, the content of the component (C) is 2 to 6 mass%, and the component (B) has an average particle diameter of 20 to It is 50 micrometers, and (C1) component and (C2) component are set as the resin composition comprised from a specific component.

Description

Liquid crystalline resin composition for camera module {LIQUID CRYSTAL RESIN COMPOSITION FOR CAMERA MODULES}

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

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

 In the case of precision instruments, especially optics with lenses, fine dust and dirt 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. For the purpose of preventing such deterioration of optical characteristics, the parts constituting the camera module (hereinafter, also referred to as "camera module parts") are usually ultrasonically cleaned prior to assembly, and have small particles, oils, dust, etc. adhered to the surface. Is removed.

 As described above, the molded article formed by molding the liquid crystalline resin composition is likely to be peeled off from the surface of the molded article because the molecular orientation of the polymer is particularly large at the surface portion, and ultrasonic cleaning of the molded article causes the surface to be peeled off to cause fluffing. In this way, the brushed portion in which the fluff is generated 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 raising of the surface of a molded object, and further, the liquid crystalline for camera modules for manufacturing the molded object which a surface of a molded object does not raise easily. Resin composition is required.

In addition, according to the studies of the present inventors, when a molded body such as a lens holder is manufactured by molding a conventional liquid crystal resin composition for a camera module, blisters (swelling) may occur, which may cause an operation as a camera module. have.

Further, according to the studies by the present inventors, when a molded body such as a lens holder housing is manufactured by molding a conventional liquid crystal resin composition for a camera module, the molding shrinkage ratio is large or too small (expansion), which is poor in assembling the camera module. It may also result.

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

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a camera module component whose surface is not easily brushed, mechanical strength is high, blisters are less likely to occur, dimensional stability is high, and bending deformation is suppressed. It is providing the liquid crystalline resin composition for camera modules for manufacturing.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly studied in order to solve the said subject. As a result, it turned out that the raising of the surface can be suppressed by using liquid crystalline resin composition for camera modules containing a liquid crystalline resin, a specific plate-shaped filler, and a specific copolymer in a specific ratio.

Moreover, about generation | occurrence | production of a blister, it discovered that it can suppress by using a specific amount of specific plate-shaped fillers, such as a mica. That is, by increasing the content of the plate-shaped filler to increase the melt viscosity of the liquid crystalline resin composition for the camera module, to increase the melt tension of the resin composition to prevent air from infiltrating into the molten resin, thereby suppressing the occurrence of blisters It was.

Moreover, about dimensional stability, it turned out that it can raise by using a specific amount of specific plate-shaped fillers, such as a mica. The present inventors estimated that the shaping | molding shrinkage of the flow direction of the liquid crystalline resin composition for camera modules is negative (that is, the said resin composition expands) and lowers dimensional stability. Then, the anisotropy was disrupted by adding the said plate-shaped filler to the liquid crystalline resin composition for camera modules, and the dimensional stability was improved by shifting the shaping | molding shrinkage of the flow direction of the said resin composition to positive (that is, shrinkage).

In addition, it was found that the bending deformation can be suppressed by using a specific amount of a specific plate-like filler such as mica.

As mentioned above, it discovered that the said subject could be solved and came to complete this invention. More specifically, the present invention provides the following.

(1) (A) liquid crystalline resin, (B) plate-shaped filler, and (C1) olefin type copolymer and (C2) styrene type copolymer, At least 1 sort (s) is contained, It contains (A Content of 64-78 mass% of (B) component is 20-30 mass% of content of (B) component, content of (C) component is 2-6 mass%, and said (B) plate-shaped filler has an average particle diameter of 20 It is -50 micrometers, The said (C1) olefin copolymer consists of the glycidyl ester of an alpha olefin and the alpha, (beta)-unsaturated acid, The said (C2) styrene copolymer is styrene and alpha, beta -Liquid crystalline resin composition for camera modules comprised from glycidyl ester of unsaturated acid.

(2) Said (B) plate-shaped filler is liquid crystalline resin composition for camera modules as described in mica (1).

(3) (D) The liquid crystalline resin composition for camera modules as described in (1) or (2) which further contains carbon black and whose content is 1-5 mass%.

When the components for the camera module are manufactured using the liquid crystalline resin composition for the camera module of the present invention as a raw material, the surface is not easily raised, the mechanical strength is high, the blister does not easily occur, the dimensional stability is high, and the bending deformation is high. A suppressed camera module component can be obtained.

1 is a cross-sectional view schematically showing a general camera module.
FIG. 2 is a top view showing a molded product used to confirm the number of blister generation samples in Examples and Comparative Examples. FIG.
FIG. 3 is a top view showing measurement points of test piece dimensions measured when molding shrinkage ratios are obtained in Examples and Comparative Examples.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described. However, the present 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) plate-shaped filler, and (C) copolymer.

[(A) Liquid Crystalline Resin]

(A) liquid crystalline resin used by this invention refers to the melt-processable polymer which has a 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 the anisotropic molten phase can be confirmed by observing the molten sample which was put on the Leitz hot stage at 40 times the magnification using a Leitz polarizing microscope under nitrogen atmosphere. When the liquid crystalline polymer which can be applied to the present invention is inspected between orthogonal polarizers, polarization is usually transmitted even in the state of melting stop, and optically anisotropy is exhibited.

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

At least one or more compounds selected from the group of aromatic hydroxycarboxylic acids, aromatic hydroxyamines and aromatic diamines, particularly preferably as (A) aromatic polyesters or aromatic polyesteramides as liquid crystalline resins applicable to the present invention. It is aromatic polyester and aromatic polyester amide which have as a structural component.

More specifically,

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

(2) mainly one or two or more of (a) aromatic hydroxycarboxylic acids and derivatives thereof, (b) one or two or more of aromatic dicarboxylic acids, alicyclic dicarboxylic acids and derivatives thereof, ( c) polyesters composed of at least one or two or more of aromatic diols, alicyclic diols, aliphatic diols, and derivatives thereof;

(3) mainly (a) one or two or more kinds of aromatic hydroxycarboxylic acids and derivatives thereof, (b) one or two or more kinds of aromatic hydroxyamines, aromatic diamines and derivatives thereof, and (c) aromatics Polyesteramides composed of one kind or two or more kinds of dicarboxylic acids, alicyclic dicarboxylic acids, and derivatives thereof;

(4) mainly (a) one or two or more kinds of aromatic hydroxycarboxylic acids and derivatives thereof, (b) one or two or more kinds of aromatic hydroxyamines, aromatic diamines and derivatives thereof, and (c) aromatics Polyesteramides comprising one or two or more of dicarboxylic acids, alicyclic dicarboxylic acids and derivatives thereof, and (d) at least one or two or more kinds of aromatic diols, alicyclic diols, aliphatic diols and derivatives thereof; Can be mentioned. And a molecular weight modifier can be used together to said structural component as needed.

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- Dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl, hydroquinone, resorcin, a compound represented by the following general formula (I), and the following general formula (II) Aromatic diols such as a compound to be represented; 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 -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 a said monomer compound (or mixture of monomers) by a well-known method using direct polymerization method or transesterification method, Usually, melt polymerization method, Slurry polymerization and the like. The compounds having an ester forming ability may be used for polymerization in the form as it is, or may be modified from a precursor to the derivative having the ester forming ability in a 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. Generally the usage-amount of a catalyst is about 0.001-1 mass% with respect to the total weight of a monomer, Especially about 0.01-0.2 mass% is preferable. The polymer produced by these polymerization methods can further increase the molecular weight by solid phase polymerization heating under reduced pressure or inert gas, if necessary.

The melt viscosity of (A) liquid crystalline resin obtained by the above method is not specifically limited. Generally, the melt viscosity at the molding temperature can be 10 MPa or more and 600 MPa or less 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 64-78 mass%. When content of (A) component is 64 mass% or more, it is preferable from the reason of fluidity | liquidity and the suppression of raising of the surface of a molded object, and when content of (A) component is 78 mass% or less, it is preferable from the reason of heat resistance. In addition, preferable content of (A) component is 66-72 mass%.

[(B) Plate Fillers]

(B) The 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 deformation temperature required as a camera module are easily maintained, and the effect of suppressing warpage deformation of the molded body tends to be increased. . 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 average particle diameter.

As long as it is a plate-shaped filler which satisfy | fills the above shape, any filler can be used, As a (B) plate-shaped filler, a mica, talc, glass flakes, various metal foils, etc. are mentioned. You may use 2 or more types as (B) component. In this invention, it is preferable to use mica and talc as (B) component, and it is more preferable to use mica.

Content of (B) component is 20-30 mass% in the liquid crystalline composition for camera modules of this invention. If content of (B) component is 20 mass% or more, a blister will hardly generate | occur | produce, and if it is 30 mass% or less, the raising effect on the surface of a molded object will become high easily. Preferable said content is 23-27 mass%.

[(C) Copolymer]

The (C) copolymer is at least one selected from the (C1) olefin copolymer and the (C2) styrene copolymer. Mixing (C) component with the liquid crystalline resin composition for camera modules contributes to suppressing the raising of the surface of a molded object at the time of ultrasonic-cleaning the molded object formed by shape | molding this composition.

The reason for suppressing napping is not clear, but it is thought that the compounding state changes the surface state of the molded body by blending a certain amount, and the change contributes to suppressing napping.

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

(alpha) -olefin is not specifically limited, For example, ethylene, propylene, butene, etc. are mentioned, Among these, ethylene is used preferably. Glycidyl ester of (alpha), (beta)-unsaturated acid is represented by following General formula (IV). Glycidyl ester units of α, β-unsaturated acids are, for example, acrylic acid glycidyl ester, methacrylic acid glycidyl ester, ethacrylic acid glycidyl ester, itaconic acid glycidyl ester, and the like. Glycylate glycidyl ester is preferable.

It is preferable that content of the (alpha) -olefin in (C1) olefin copolymer is 87-98 mass%, and content of the glycidyl ester of (alpha), (beta)-unsaturated acid is 13-2 mass%.

The (C1) olefin copolymer used in the present invention is an acrylonitrile, acrylic acid ester, methacrylic acid ester, α-methylstyrene, maleic anhydride as the third component in addition to the two components within the range of not impairing the present invention. One kind or two or more kinds of olefinically unsaturated esters such as 0 to 48 parts by mass may be contained with respect to 100 parts by mass of the two components.

The olefin copolymer which is (C1) component of this invention can be easily prepared by a normal radical polymerization method using the monomer of each component and a radical polymerization catalyst. More specifically, glycidyl esters of α-olefins and α, β-unsaturated acids are usually contained in the presence of a radical generator, at 500 to 4000 atmospheres, and 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.

The styrene-based copolymer of (C2) is composed of styrene and glycidyl ester of?,?-Unsaturated acid. 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, styrene bromide, divinylbenzene, etc. are mentioned as styrene, Styrene is used preferably.

The (C2) styrene copolymer used in the present invention may be a polycopolymer obtained by copolymerization using at least one other vinyl monomer as a third component in addition to the two components. Suitable as the third component is one kind or two or more kinds of olefinically unsaturated esters such as acrylonitrile, acrylic acid ester, methacrylic acid ester and maleic anhydride. The copolymer which introduce | transduced 40 mass% or less in repeating units derived from these in a (C2) styrene-type copolymer is preferable as a (C2) component.

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

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

As the (C) copolymer, the (C1) olefin copolymer is preferable in terms of heat resistance, but the ratio between the (C1) component and the (C2) component can be appropriately selected depending on the required properties.

Content (the total amount of (C1) component and (C2) component) of (C) copolymer is 2-6 mass% in the resin composition for camera modules of this invention. Content of (C) component is 2 mass% or more in the point which suppresses raising of the surface of a molded object, and 6 mass% or less is necessary for the reason of obtaining a favorable molded object, without impairing fluidity. More preferable said content is 3-5 mass%.

[(D) carbon black]

Carbon black (D) 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 includes a lump form formed by agglomeration of primary particles, but a molded article formed by molding the resin composition of the present invention unless a large amount of lump forms of 50 μm or more are included. Many millet bumps on the surface (fine millet-like bumps (fine irregularities) in which carbon black is agglomerated) are not easily generated. When the content rate of the particles having a lump form particle diameter of 50 µm or more is 20 ppm or less, the effect of suppressing the raising of the surface of the molded body is likely to be increased. Preferable content rate is 5 ppm or less.

As the compounding quantity of (D) carbon black, the range of 1-5 mass% is preferable in the liquid crystalline resin composition for camera modules. When the compounding quantity of carbon black is less than 1 mass%, the black-blackness of the resin composition obtained falls, light-shielding property becomes unstable, and when it exceeds 5 mass%, it is uneconomical and the possibility of generation of a narrow bump becomes high.

[Other Ingredients]

In the liquid crystalline resin composition for camera modules of the present invention, other polymers, known substances added to synthetic resins in general, that is, stabilizers such as antioxidants and ultraviolet absorbers, antistatic agents, Colorants such as flame retardants, dyes and pigments, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents, and powdery fillers such as silica and quartz powder may also be appropriately added depending on the required performance.

In addition, unless the effect of this invention is impaired, the liquid crystalline resin composition for camera modules of this invention may also contain an inorganic filler other than (B) plate-shaped filler, and (B) does not contain an inorganic filler other than plate-shaped filler. It may be. As inorganic fillers other than (B) plate-shaped filler, the fibrous filler whose average fiber diameter is 1.0 micrometer or less, and average fiber length is 5-50 micrometers, and plate-shaped fillers other than (B) component are mentioned, for example. Hereinafter, the fibrous filler will be described.

The average fiber diameter of the said fibrous filler is 1.0 micrometer or less, and a preferable average fiber diameter is 0.3-0.6 micrometer. If the said average fiber diameter is 1.0 micrometer or less, the anti-napping effect on the surface of a molded object will become high easily. In this specification, as an average fiber diameter, a stereomicroscope image is taken into a PC from a CCD camera, and the value measured using the image processing method by the image measuring machine is employ | adopted.

Moreover, the average fiber length of the said fibrous filler is 5-50 micrometers, preferable average fiber length is 5-30 micrometers, and more preferable average fiber length is 7-30 micrometers. If the said average fiber length is 5 micrometers or more, the mechanical strength and load deformation temperature which are required as a camera module will be easy to be maintained, and if it is 50 micrometers or less, the raising effect of raising the surface of a molded object will become easy. In this specification, as an average fiber length, a stereomicroscope image is taken into a PC from a CCD camera, and the value measured using the image processing method by an image measuring device is employ | adopted.

Any fiber can be used as long as it is a fibrous filler that satisfies the above shape. Examples of the fibrous filler include glass fiber, carbon fiber, asbestos fiber, silica fiber, silica alumina fiber, zirconia fiber, boron nitride fiber, Inorganic fibrous materials such as 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. You may use 2 or more types as said fibrous filler. In the present invention, potassium titanate fibers can be used as the fibrous filler.

It is preferable that content of the said fibrous filler is 5-14 mass% in the liquid crystalline composition for camera modules of this invention. If the said content is 5 mass% or more, the mechanical strength and load deformation temperature required as a camera module will be easy to be ensured, and if it is 14 mass% or less, the raising effect of the surface of a molded object will become high easily. More preferable said content is 7-12 mass%.

[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 liquid crystal for camera module by mix | blending said (A), (B) and (C) component and optionally the said (D) component and other components, and melt-kneading these using a single-axis or twin-screw extruder. The resin composition is prepared.

[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.

It is preferable that melt viscosity of the liquid crystalline resin composition for camera modules of this invention obtained as mentioned above is 50 Pa.sec or less. It is also one of the characteristics of the liquid crystalline resin composition for camera modules of this invention that fluidity is high and it is excellent in moldability. Here, the melt viscosity adopts a value obtained by a measuring method in accordance with ISO 11443 under conditions of a cylinder temperature of 350 ° C. and a shear rate of 1000 sec ⁻¹ .

It is preferable that load deformation temperature of the liquid crystalline resin composition for camera modules of this invention is 200 degreeC or more. It is also one of the characteristics of the liquid crystalline resin composition for camera modules of this invention that it is excellent in heat resistance. The load deformation temperature adopts the value measured by the method based on ISO75-1, 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 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 assembled into a finished product, the dust generated by raising the surface of the 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 shown typically in FIG. As shown in FIG. 1, the camera module 1 includes a substrate 10, an optical element 11, a lead wiring 12, a lens holder 13, a barrel 14, a lens 15, and an IR filter ( 16) and a guide 17.

The optical element 11 is disposed on the substrate 10, and is electrically connected to the lead wiring 12 between the optical element 11 and the substrate 10.

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 formed at the top thereof, and a spiral groove portion is formed at the opening wall surface.

The barrel 14 is cylindrical, and is maintained so that the lens 15 is almost horizontal inside the cylinder. Moreover, the spiral side convex part is formed in the side wall of one end of a cylinder, and this barrel convex part and the spiral groove part formed in the opening wall surface of the lens holder 13 are screwed together, and the barrel 14 becomes a lens holder ( 13). In addition, the IR filter 16 is disposed at one end of the barrel 14 so as to cover 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 is composed 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. The distance between the lens 15 and the optical element 11 changes as the user moves up and down the guide 17. 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 the barrel 14, which are components for the camera module, can be produced 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 these parts. When the lens holder 13 or the barrel 14 is manufactured using a general liquid crystalline resin composition as a raw material, the following problems arise.

In the molded article formed by molding a general liquid crystalline resin composition, since the molecular orientation of the polymer is particularly large at the surface portion, the molded article surface is likely to be raised, 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.

Camera module components such as the lens holder 13 and the barrel 14 are ultrasonically cleaned before being assembled to the camera module 1 for the purpose of removing surface dust and small particles. However, since the surface of the molded object formed by molding a general liquid crystalline resin composition is easy to be brushed, the surface is fluffed when ultrasonically cleaned. Since such a problem arises, the molded object formed by shape | molding a liquid crystalline resin composition cannot be ultrasonically cleaned normally.

The above focus adjustment is performed by the lens holder 13 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. 17) by up and down. At this time, the molded article formed by molding a general liquid crystalline resin composition is likely to be brushed on the surface, as described above, so that the surface may be peeled off and a peeled product may be generated. Such peeling material becomes small dust and adheres to the lens 15 etc., and it is highly likely to degrade the performance of a camera module.

As described above, when the liquid crystalline resin composition is usually used as a raw material for the lens holder 13 or the barrel 14, defects tend to occur. However, when the liquid crystalline resin composition for the camera module of the present invention is made into a molded article, Since the surface state of the molded object is improved to such an extent that raising problems rarely occur even when ultrasonically cleaning the molded product, it can be suitably used as a raw material for the lens holder 13 and the barrel 14.

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.

<Material>

Liquid crystalline resin (liquid crystalline polyesteramide resin): Vectra (registered trademark) E950i (manufactured by Polyplastics Co., Ltd.)

Fibrous filler 1: Otsuka Chemical Co., Ltd. Tismo N-102 (potassium titanate fiber, average fiber diameter 0.3-0.6 μm, average fiber length 10-20 μm)

Fibrous filler 2: Nitto Spinning Co., Ltd. product PF70E001 (milled fiber, average fiber diameter 10㎛, average fiber length 70㎛)

Plate-shaped filler 1: Yamaguchi Mica Co., Ltd. AB-25S (Mica, average particle diameter 24㎛)

Plate-shaped filler 2: Crown Talc PP (Talk, average particle diameter 12.8 μm, average aspect ratio 6) manufactured by Matsumura Industries Co., Ltd.

Olefin-based copolymer: Sumitomo Chemical Co., Ltd. Bond Fast 2C (ethylene-glycidyl methacrylate copolymer (containing 6% by mass of glycidyl methacrylate))

Carbon Black: VULCAN XC305 manufactured by Cabot Japan Co., Ltd. (carbon black, particle size of 20 nm or more, particle size of 50 μm or more, 20 ppm or less, granular)

<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 (The Nippon Seiko Co., Ltd. product TEX30 (alpha) type) in the ratio shown in Table 1, and the liquid crystal resin composition pellets for camera modules were obtained.

Melting Viscosity

Melt viscosity of the liquid crystalline resin composition for camera modules of Examples and Comparative Examples was measured using the pellets. Specifically, the appearance melt viscosity was measured in accordance with ISO 11443 under the condition of a cylinder temperature of 350 ° C. and a shear rate of 1000 sec ^{−1 using} a capillary rheometer (Capillary Graph 1D manufactured by Toyo Seiki Co., Ltd .: piston diameter 10 mm). 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.

<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, bending strength and bending elastic modulus were measured in accordance with ASTM D790. The results are shown in Table 1.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 90 ℃

Injection Speed: 33mm / sec

Holding pressure: 50MPa

<Load strain temperature>

The pellet of the Example and the comparative example was shape | molded using the molding machine ("SE100DU" by Sumitomo Heavy Industries, Ltd.) on the following molding conditions, and the measurement test piece (4mm * 10mm * 80mm) was obtained. Then, the load distortion 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.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 80 ℃

Injection Speed: 33mm / sec

<Evaluation of Raising States of Surfaces (Surface Raising Inhibition Effect)>

The pellet of the Example and the 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 x 120 mm x 0.8 mm was obtained. What cut this molded object in half was used as a test piece.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 90 ℃

Injection speed: 80mm / sec

〔evaluation〕

The molded product cut in half was put in an ultrasonic cleaner (output 300 W, frequency 45 kHz) in water at room temperature for 3 minutes. Thereafter, the molded products before and after hanging on an ultrasonic cleaner were compared, and the area (napping area) of the part where the fluff occurred on the surface of the molded product was evaluated by an image measuring device (LUZEXFS manufactured by Nireco Co., Ltd.). The evaluation area was 750 mm ² (12.5 mm x 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 area of raising, the higher the effect of suppressing raising.

<Blister Generated Samples>

The pellet of an Example and a comparative example was shape | molded using the molding machine (the Sodick Co., Ltd. product "TR-100 EH") on the following molding conditions, and the molded object sample (dimension of the part which has maximum area: 50 mm x) shown in FIG. 5 mm x 0.2 mm). At that time, the gas vent was blocked with grease to make gas discharge difficult, so that blisters were easily generated. It was visually observed whether or not blisters were generated for the 20 molded samples and the number of blister generation samples was confirmed. The results are shown in Table 1.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 140 ℃

Injection speed: 150mm / sec

Holding pressure: 75MPa

Molding shrinkage

The pellet of an Example and a comparative example was shape | molded using the molding machine ("SE-100 DU" by Sumitomo Heavy Industries, Ltd.) on the following molding conditions, and the test piece for measurement (80 mm x 80 mm x 1 mmt) was obtained. The dimension of the said test piece left still on one day was measured in the flow direction measurement location and right angle direction measurement location shown in FIG. From the measured test piece dimension and the mold dimension at the place on the mold corresponding to the said measurement location, the molding shrinkage ratio was calculated | required according to Formula: (mold dimension-test piece dimension) / mold dimension x100. The mold dimension was 79.981 mm in the flow direction and 79.994 mm in the right angle direction. The results are shown in Table 1.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 80 ℃

Injection Speed: 33mm / sec

Holding pressure: 50MPa

<Top view>

[Floor plan]

The pellet of the Example and the comparative example was shape | molded using the molding machine ("SE-100DU" by Sumitomo Heavy Industries, Ltd.), and five sheets of 80 mm x 80 mm x 1 mm flat test pieces 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. And 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 when a square having a side of 74 mm is placed on the main plane of the flat specimen so that the distance from each side of the main plane is 3 mm. , And the positions corresponding to the intersections of the two diagonals of this square. The plane parallel to the horizontal plane whose height from the horizontal plane was the same as the average height was taken 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 calculated for the other four flat plate specimens, and the five values obtained were averaged to obtain a planar value. The results are shown in Table 1.

〔Molding conditions〕

Cylinder temperature: 350 ℃

Mold temperature: 80 ℃

Injection Speed: 33mm / sec

Holding pressure: 50MPa

As can be seen from the results shown in Table 1, it was confirmed that the molded article produced using the pellets of the example did not fluff even when ultrasonically cleaned. In addition, it was confirmed that the molded article had a small number of blister generation samples, and the molding shrinkage in the flow direction was positive. In addition, the molded article had a small numerical value in plan view. From these results, the molded article formed by molding the pellets of the examples is significantly different in surface state from the molded article formed by molding the usual liquid crystalline resin composition pellets such as Comparative Examples, does not easily cause blisters, and has high dimensional stability. It can be said that bending 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. Therefore, by molding the pellets of the embodiment, it is possible to manufacture a component for a camera module, which has a high mechanical strength and specifically does not easily cause a defect that is cracked due to, for example, a driving shock.

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

Claims (3)

(A) liquid crystalline resin,
(B) a plate filler, and
At least one (C) copolymer selected from (C1) olefin copolymer and (C2) styrene copolymer
Containing,
Content of (A) component is 64-78 mass%, content of (B) component is 20-30 mass%, content of (C) component is 2-6 mass%,
The said (B) plate-shaped filler is 20-50 micrometers in average particle diameter,
Said (B) plate-shaped filler is mica,
The (C1) olefin copolymer is composed of a glycidyl ester of an α-olefin and an α, β-unsaturated acid,
The said (C2) styrene-type copolymer is a liquid crystalline resin composition for camera modules comprised from glycidyl ester of styrene and (alpha), (beta)-unsaturated acid. The method of claim 1,
The said liquid crystalline resin composition for camera modules does not contain an inorganic filler other than the said (B) plate-shaped filler, The liquid crystalline resin composition for camera modules. The method according to claim 1 or 2,
Content of (A) component is 66-72 mass%, content of (B) component is 20-30 mass%, content of (C) component is 2-6 mass%,
(D) The liquid crystal resin composition for camera modules containing carbon black further and whose content is 1-5 mass%.

Images