JP2021004345A - Compact - Google Patents

Abstract

To provide a compact having reduced warp deformation and dimensional change.SOLUTION: A compact having a thin-walled part having an average thickness of 3 mm or smaller and a length in the longitudinal direction of four times or larger than a length in a short side direction orthogonal to the longitudinal direction, in which the thin-walled part includes a resin composition containing (a) an amorphous resin, (b) a fibrous inorganic filler having an aspect ratio (L/D) of an average fiber length L and an average fiber diameter D of 8 or larger, and (c) a flake-like inorganic filler having an aspect ratio (L1/L2) of an average major diameter L1 and an average minor diameter L2 of 3 or smaller.SELECTED DRAWING: None

Description

The present invention relates to a molded product.

A molded product made of a resin composition shrinks when the resin in the resin composition changes from a molten state to a solid state due to a difference in specific volume between a molten state and a solid state, so that parts for electronic devices, etc. In a molded body used as a part that requires particularly high precision, dimensional accuracy at the time of molding is highly required (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2013-29662

By the way, in a conventional molded product having a thin portion having an average thickness of 3 mm or less, the thin portion may be warped and deformed into a twisted shape as a whole, and the thin portion is relatively relatively in the longitudinal direction. In the case of a long shape, in addition to the above-mentioned warp deformation, a dimensional change that shrinks in the longitudinal direction may occur with time after molding.

Therefore, an object of the present invention is to provide a molded product in which warpage deformation and dimensional change are reduced.

As a result of diligent studies to solve the above problems, the present inventors have found that the thin portion is found in a molded product having a thin portion having a specific shape having an average thickness of 3 mm or less and a relatively long length in the longitudinal direction. We have found that the above problems can be solved by including an amorphous resin and a specific inorganic filler, and have completed the present invention.

That is, the present invention is as follows.

[1] It has a thin portion having an average thickness of 3 mm or less and a length in the longitudinal direction of 4 times or more the length in the lateral direction orthogonal to the longitudinal direction.
The thin portion is (a) an amorphous resin, (b) a fibrous inorganic filler having an aspect ratio (L / D) of 8 or more between the average fiber length L and the average fiber diameter D, and (c). A molded product comprising a resin composition containing a scaly inorganic filler having an aspect ratio (L1 / L2) of an average major axis L1 and an average minor axis L2 of 3 or less.
[2] The molded product according to [1], wherein the (a) amorphous resin is a polyphenylene ether-based resin.
[3] Ratio of the content of the (c) scaly inorganic filler in the resin composition to the content of the (b) fibrous inorganic filler in the resin composition ((c) component / ( b) The molded product according to [1] or [2], wherein the component) is 0.4 to 2.0.
[4] The molded product according to any one of [1] to [3], wherein the fibrous inorganic filler (b) is glass fiber.
[5] The molded product according to any one of [1] to [4], wherein the (c) scaly inorganic filler is mica.
[6] The molded product according to any one of [1] to [5], wherein the thin portion is formed by injection molding.

According to the present invention, it is possible to provide a molded product in which warpage deformation and dimensional change are reduced.

Hereinafter, embodiments for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in more detail, but the present invention is not limited to this, and various aspects are not deviated from the gist thereof. It can be transformed.

[Molded product]
The molded body of the present embodiment has a thin portion having an average thickness of 3 mm or less and a length in the longitudinal direction which is four times or more the length in the lateral direction orthogonal to the longitudinal direction. However, (a) an amorphous resin, (b) a fibrous inorganic filler having an aspect ratio (L / D) of 8 or more between the average fiber length L and the average fiber diameter D, and (c) the average major axis L1 It is characterized by containing a resin composition containing a scaly inorganic filler having an aspect ratio (L1 / L2) of 3 or less with an average minor axis L2.

In the molded product of the present embodiment, since the thin portion contains the resin composition, warpage deformation and dimensional change can be reduced in the thin portion of the molded product.
More specifically, since the thin portion of the molded product having a predetermined shape as described above has a thin thickness and a long shape in the longitudinal direction, the resin composition can be formed when the thin portion is molded. There was a case of drift. When such a drift occurs, not only the thin portion warps and deforms into a twisted shape as a whole after molding, but also a dimensional change that shrinks in the longitudinal direction with time after molding may occur. .. In the molded product of the present embodiment, the thin portion contains (a) an amorphous resin having high dimensional stability during molding, and (b) a fibrous inorganic filler and (c) a scaly inorganic filler. Since it contains, (c) the scaly inorganic filler can mainly reduce the warp deformation, and (b) the fibrous inorganic filler can mainly reduce the dimensional shrinkage change in the longitudinal direction. ..

The molded product of the present embodiment may contain a resin composition in a portion other than the thin portion, and the resin composition may be the same as or different from the resin composition contained in the thin portion. You can also do it.

The molded product of the present embodiment is not particularly limited, but can be used, for example, as a part for which dimensional accuracy at the time of molding is highly required, such as a part for an electronic device.

[Thin part]
The thin portion of the molded body of the present embodiment is at least a part of the molded body, has an average thickness of 3 mm or less, and has a length in the longitudinal direction four times the length in the lateral direction orthogonal to the longitudinal direction. This is the part that is above.
The thin portion has a shape extending in at least one direction, and is not particularly limited, but is preferably plate-shaped. Further, the thin portion may have, for example, a shape curved in the thickness direction or a curved shape in a plan view.

The length of the thin portion in the longitudinal direction is four times or more, and six times or more, the length in the lateral direction orthogonal to the longitudinal direction from the viewpoint of (b) orienting the fibrous inorganic filler in the longitudinal direction. It is preferably present, and more preferably 10 times or more.
Further, from the viewpoint of the strength of the molded body, the thin portion has a length of preferably 100 to 400 mm, more preferably 150 to 350 mm in the longitudinal direction, and preferably a length of 10 to 65 mm in the lateral direction. It is more preferably 15 to 55 mm, still more preferably 25 to 45 mm.
In the present disclosure, the longitudinal direction of the thin portion is such that the shortest distance measured along the outer surface of the thin portion between the two points on the outer surface of the thin portion is the maximum. The direction connecting the two points is referred to, and the lateral direction is the direction orthogonal to the longitudinal direction.
Further, the "length in the longitudinal direction" and the "length in the lateral direction" are lengths measured along the shape of the outer surface of the thin portion, respectively.

The average thickness of the thin portion is 3 mm or less, preferably 2.5 mm or less, and more preferably 2 mm or less, from the viewpoint of reducing the size and weight of the molded product. It is preferable that the thin portion has a thickness of 3 mm or less as a whole, but even if there is a portion having a thickness of more than 3 mm, the average thickness of the entire thin portion may be 3 mm or less. Just do it.

The thin portion preferably has a warp deformation (flatness) of 210 μm or less and a dimensional change of 10 μm or less, and more preferably a warp deformation of 170 μm or less and a dimensional change of 5 μm or less. ..
The warp deformation and dimensional change can be measured using, for example, a 3D microscope, and specifically, can be measured by the method described in Examples described later.

[Resin composition]
The resin composition contained in the thin portion of the present embodiment includes (a) an amorphous resin and (b) a fiber having an aspect ratio (L / D) of 8 or more between the average fiber length L and the average fiber diameter D. It contains a plastic inorganic filler and (c) a scaly inorganic filler having an aspect ratio (L1 / L2) of an average major axis L1 and an average minor axis L2 of 3 or less.

[(A) Amorphous resin]
The resin composition contained in the thin portion of the molded product of the present embodiment contains (a) an amorphous resin. When the resin composition contains (a) an amorphous resin, the dimensional stability of the thin portion at the time of molding can be improved.

The content of the (a) amorphous resin in the thin portion of the present embodiment is not particularly limited, but is 40 to 90% by mass with respect to 100% by mass of the resin composition contained in the thin portion. It is preferably, more preferably 50 to 90% by mass, and even more preferably 60 to 90% by mass.
When the content is 40 to 90% by mass, a thin portion having a good balance between mechanical properties and dimensional accuracy can be obtained.

The (a) amorphous resin of the present embodiment is not particularly limited as long as it is a resin having amorphousness. For example, polystyrene resin, rubber-reinforced polystyrene resin (high impact-polystyrene resin), acrylonitrile- Polystyrene resin such as butadiene-styrene copolymer (hereinafter also referred to as "ABS resin"); Polystyrene resin such as polycarbonate resin, polycarbonate resin / ABS resin alloy, polycarbonate resin / polybutylene terephthalate resin alloy; polyphenylene ether resin, Polyphenylene ether resin / polystyrene resin alloy, polyphenylene ether resin / high impact-polystyrene resin alloy, polyphenylene ether resin / polystyrene resin / high impact-polystyrene resin alloy, polyphenylene ether resin / polypropylene resin alloy, polyphenylene ether resin / polyphenylene sulfide resin alloy, etc. Polystyrene ether-based resin and the like can be mentioned.

Further, as the (a) amorphous resin, a resin having a high glass transition temperature and relatively easy to make flame-retardant is particularly desirable from the viewpoint of heat resistance, dimensional accuracy, and flame retardancy, and a polycarbonate resin or a polycarbonate resin or It is preferably a polyphenylene ether-based resin, preferably a polycarbonate resin, a polycarbonate resin / ABS resin alloy, a polyphenylene ether resin / polystyrene resin alloy, a polyphenylene ether resin / high impact-polystyrene resin alloy, or a polyphenylene ether resin / polystyrene resin / high impact-. More preferably, it is a polystyrene resin alloy. Further, from the viewpoint that weight reduction is possible, polyphenylene ether resin / polystyrene resin alloy, polyphenylene ether resin / high impact-polystyrene resin alloy, or polyphenylene ether resin / polystyrene resin / high impact-polystyrene resin alloy is particularly preferable.

Here, "amorphous" in the (a) amorphous resin of the present embodiment means that the crystallization enthalpy ΔH is 5 J / g or less. The crystallization enthalpy ΔH is preferably 0 J / g.
The crystallization enthalpy ΔH can be obtained, for example, by differential scanning calorimetry (DSC measurement) according to JIS-K7122.

[[Polycarbonate resin]]
The polycarbonate-based resin may be bisphenol A-type polycarbonate polymerized with bisphenol A, or various types of polycarbonate with high heat resistance or low water absorption rate polymerized with other divalent phenol-based compounds. ..
Examples of the other dihydric phenolic compounds include hydroquinone, 4,4'-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, and 2,2-bis. (3,5-dimethyl-4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ketone, Examples thereof include bis (4-hydroxyphenyl) ether and halogenated bisphenol such as 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane.
Further, the polycarbonate resin may be a branched polycarbonate obtained by polymerizing a trifunctional phenol in addition to the linear polycarbonate, and further may be an aliphatic dicarboxylic acid, an aromatic dicarboxylic acid, or a divalent aliphatic or fat. It may be a copolymerized polycarbonate obtained by copolymerizing a cyclic alcohol.
Only one type of polycarbonate resin may be used alone, or two or more types may be mixed and used.

The polycarbonate-based resin may be produced by any conventionally known production method. When a polycarbonate resin is produced by interfacial polycondensation, a terminal terminator of monohydric phenols is usually used.

Further, the polycarbonate resin can include a styrene-acrylonitrile copolymer (AS resin) and an acrylonitrile-butadiene-styrene copolymer (ABS resin).
The content of the AS resin or ABS resin is preferably 5 to 50 parts by mass, and more preferably 20 to 40 parts by mass with respect to 100 parts by mass of the polycarbonate resin. Resin compositions containing polycarbonate-based resins in such a blending range tend to have good heat resistance and flame retardancy.

[[Polyphenylene ether-based resin]]
The polyphenylene ether-based resin is preferably a homopolymer or a copolymer having a repeating unit (structural unit) represented by the following general formula (1) and / or general formula (2).

（一般式（１）および（２）中、Ｒ１、Ｒ２、Ｒ３、Ｒ４、Ｒ５、およびＲ６は、各々独立に、水素原子、炭素数１〜４のアルキル基、炭素数６〜９のアリール基またはハロゲン原子を表す。但し、Ｒ５およびＲ６は、同時に水素ではない。）
また、前記アルキル基の好ましい炭素数は１〜３であり、前記アリール基の好ましい炭素数は６〜８であり、前記一価の残基の中でも水素原子が好ましい。
なお、上記一般式（１）、（２）で表される繰り返し単位の数については、ポリフェニレンエーテル系樹脂の分子量分布により様々であるため、特に制限されることはない。

(In the general formulas (1) and (2), R1, R2, R3, R4, R5, and R6 are independently hydrogen atoms, alkyl groups having 1 to 4 carbon atoms, and aryl groups having 6 to 9 carbon atoms, respectively. Or represents a halogen atom, where R5 and R6 are not hydrogen at the same time.)
The alkyl group preferably has 1 to 3 carbon atoms, and the aryl group preferably has 6 to 8 carbon atoms. Among the monovalent residues, a hydrogen atom is preferable.
The number of repeating units represented by the general formulas (1) and (2) varies depending on the molecular weight distribution of the polyphenylene ether-based resin, and is not particularly limited.

Typical examples of homopolymers of polyphenylene ether are poly (2,6-dimethyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, and poly (2, 6-diethyl-1,4-phenylene) ether, poly (2-ethyl-6-n-propyl-1,4-phenylene) ether, poly (2,6-di-n-propyl-1,4-phenylene) Ether, poly (2-methyl-6-n-butyl-1,4-phenylene) ether, poly (2-ethyl-6-isopropyl-1,4-phenylene) ether, poly (2-methyl-6-chloroethyl-) Examples thereof include 1,4-phenylene) ether, poly (2-methyl-6-hydroxyethyl-1,4-phenylene) ether, and poly (2-methyl-6-chloroethyl-1,4-phenylene) ether.

The polyphenylene ether copolymer is a copolymer having a repeating unit represented by the general formula (1) and / or the general formula (2) as a main repeating unit.
Examples include a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, a copolymer of 2,6-dimethylphenol and o-cresol, or 2,6-dimethylphenol. Examples thereof include a copolymer with 2,3,6-trimethylphenol and o-cresol.

Among the above polyphenylene ethers, poly (2,6-dimethyl-1,4-phenylene) ether is preferable.

The phenylene ether unit other than the general formulas (1) and (2) is not limited to the following, but is described in, for example, JP-A-63-301222 and the like, 2- (dialkyl). A polyphenylene ether containing an aminomethyl) -6-methylphenylene ether unit, a 2- (N-alkyl-N-phenylaminomethyl) -6-methylphenylene ether unit and the like as a partial structure is particularly preferable.

The reduced viscosity of polyphenylene ether (measured using a chloroform solution having a unit of dL / g and 0.5 g / dL at a temperature of 30 ° C. using an Ubbelohde viscous tube) is preferably 0.25 to 0.6 dL. The range is / g, more preferably 0.35-0.55 dL / g.

The polyphenylene ether-based resin of the present embodiment can be synthesized by any conventionally known method.

Further, in the present embodiment, as the polyphenylene ether-based resin, a modified polyphenylene ether in which a part or all of the constituent units constituting the polyphenylene ether is modified with an unsaturated or saturated carboxylic acid or a derivative thereof can be used.
Examples of the modified polyphenylene ether include JP-A-2-276823 (US Pat. No. 5,159,027, US Reissue Patent Invention No. 35695) and JP-A-63-108059 (US Pat. No. 5,214,109). , 5216089), JP-A-59-59724, and the like.
The modified polyphenylene ether is produced, for example, by melt-kneading an unsaturated or saturated carboxylic acid or a derivative thereof with the polyphenylene ether in the presence or absence of a radical initiator. Alternatively, it is produced by dissolving an unsaturated or saturated carboxylic acid or a derivative thereof in an organic solvent in the presence or absence of a radical initiator and reacting the polyphenylene ether in a solution.

Examples of the unsaturated carboxylic acid or a derivative thereof include maleic acid, fumaric acid, itaconic acid, maleic halide, cis-4-cyclohexene1,2-dicarboxylic acid, and endo-cis-bicyclo (2,2,1). Examples include -5-heptene-2,3-dicarboxylic acids, acid anhydrides, esters, amides, imides, etc. of these dicarboxylic acids, acrylic acids, methacrylic acids, etc., and esters, amides, etc. of these monocarboxylic acids. Be done.

In addition, examples of the saturated carboxylic acid or a derivative thereof include, in the present embodiment, a compound that can be thermally decomposed at the reaction temperature at the time of producing the modified polyphenylene ether to become a derivative of the modified polyphenylene ether. Specific examples thereof include malic acid and citric acid.

As the polyphenylene ether-based resin, only one type may be used alone, or two or more types may be used in combination.

[(B) Fibrous inorganic filler]
The resin composition of the thin portion of the molded product of the present embodiment includes (b) a fibrous inorganic filler having an aspect ratio (L / D) of 8 or more between the average fiber length L and the average fiber diameter D. Since the resin composition contains (b) the fibrous inorganic filler, it is possible to reduce the change in dimensional shrinkage mainly in the longitudinal direction of the thin portion.

(B) The fibrous inorganic filler is not particularly limited as long as the aspect ratio (L / D) is 8 or more, but for example, glass fiber, carbon fiber, calcium silicate fiber, potassium titanate fiber, etc. Examples thereof include aluminum borate fiber, wallastonite, and carbon nanotubes. Of these, glass fiber is particularly preferable from the viewpoint of the balance between dimensional accuracy and mechanical strength.
(B) As the fibrous inorganic filler, only one type may be used alone, or two or more types may be used in combination.

(B) The fibrous inorganic filler may be surface-treated with a silane coupling agent or the like. The silane coupling agent is not limited to the following, but for example, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxy. Aminosilanes such as silanes; mercaptosilanes such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane; epoxysilanes; vinylsilanes.
Only one type of silane coupling agent may be used alone, or two or more types may be used in combination. Among the silane coupling agents, aminosilanes are more preferable from the viewpoint of affinity with the resin.

Further, when (b) a glass fiber is used as the fibrous inorganic filler, it is preferable that the glass fiber further contains a sizing agent.
The sizing agent is a component to be applied to the surface of the glass fiber, and (b) the fibrous inorganic filler preferably has the sizing agent on at least a part of the surface thereof.

The coagulant includes a copolymer containing an unsaturated vinyl monomer containing carboxylic acid anhydride and an unsaturated vinyl monomer excluding the unsaturated vinyl monomer containing carboxylic acid anhydride as a constituent unit, an epoxy compound, and a poly. Examples thereof include carbodiimide compounds, polyurethane resins, homopolymers of acrylic acid, copolymers of acrylic acid with other copolymerizable monomers, and salts with primary, secondary, and tertiary amines thereof.
These sizing agents may be used alone or in combination of two or more.

The fibrous inorganic filler (b) has an average fiber diameter D of 3 to 30 μm from the viewpoint of reducing warpage deformation and dimensional change while imparting excellent mechanical strength characteristics to the thin portion. It is preferably 5 to 15 μm, more preferably 5 to 15 μm. The average fiber length L is preferably 100 to 6000 μm, more preferably 150 to 5000 μm.
(B) The fibrous inorganic filler has an aspect ratio (L / D) of 8 or more between the average fiber length L and the average fiber diameter D, preferably 8 to 250, more preferably 8 to 100, and even more preferably. It is 10 to 30.

Here, the average fiber diameter (number average fiber diameter) D and the average fiber length (weight average fiber length) L of the (b) fibrous inorganic filler in the present embodiment can be obtained as follows.
That is, for example, 100 or more (b) fibrous inorganic fillers are arbitrarily selected, observed with a digital microscope, these fiber diameters are measured, and the average value is calculated to obtain the number average fiber diameter D. Can be sought.
In addition, the fiber length is measured using a digital microscope photograph with a magnification of 500 times, and a predetermined formula (when N fiber lengths are measured, average fiber length = Σ (i = 1 → N) (Nth). The weight average fiber length L can be obtained by (fiber length of fiber) ² / Σ (i = 1 → N) (fiber length of Nth fiber)).
The fibrous inorganic filler (b) for measurement can be collected from the obtained residue by putting a thin portion of the molded product in an electric furnace and incinerating the contained organic matter.

The content of the fibrous inorganic filler (b) in the thin portion of the present embodiment is not particularly limited, but is 5 to 30% by mass with respect to 100% by mass of the resin composition contained in the thin portion. , More preferably 8 to 25% by mass, and even more preferably 10 to 20% by mass.
By setting the content to 5% by mass or more, it is possible to suppress a dimensional change in the longitudinal direction of the thin portion. Further, by setting the content to 30% by mass or less, the warp of the thin portion can be suppressed.

Further, the content of (c) scaly inorganic filler in the resin composition contained in the thin portion is relative to the content of (b) fibrous inorganic filler in the resin composition contained in the thin portion of the present embodiment. The ratio (component (c) / component (b)) is preferably 0.3 to 5.0, more preferably 0.4 to 4.0, and even more preferably 1.0 to 3. It is 0, particularly preferably 1.5 to 2.0. When the ratio is less than 1.0, (b) the content of the fibrous inorganic filler is relatively large, so that the mechanical strength can be increased. Further, when the ratio is more than 1.0, the abundance of (c) the scaly inorganic filler is relatively large, and the warp can be reduced.

[(C) Scale-like inorganic filler]
The resin composition of the thin portion of the molded product of the present embodiment contains (c) a scaly inorganic filler having an aspect ratio (L1 / L2) of an average major axis L1 and an average minor axis L2 of 3 or less. When the resin composition contains (c) a scaly inorganic filler, it is possible to reduce mainly warpage deformation of the thin portion.
The scaly shape refers to a flat particle shape in which the average thickness T is shorter than the average minor diameter L2.

(C) The scaly inorganic filler is not particularly limited as long as the aspect ratio (L1 / L2) of the average major axis L1 and the average minor axis L2 is 3 or less, but for example, glass flakes, mica, and the like. And at least one selected from the group consisting of talc.

(C) The scaly inorganic filler has an average major axis L1 of preferably 1000 μm or less, more preferably 1 to 500 μm, and further preferably 1 to 200 μm.
The average minor axis L2 is preferably 1000 μm or less, more preferably 1 to 500 μm, and further preferably 1 to 200 μm.

(C) The aspect ratio (L1 / L2) of the average major axis L1 and the average minor axis L2 of the scaly inorganic filler is 3 or less, preferably 2 or less, and more preferably 1.6 or less.
Further, (c) the scaly inorganic filler has an aspect ratio (L1 / T) of an average major axis L1 and an average thickness T preferably more than 5, more preferably 10 or more, and further preferably 30 or more.
The average major axis L1, average minor axis L2, and average thickness T of the scaly inorganic filler (c) are all number averages. (C) The average major axis L1, the average minor axis L2, and the average thickness T of the scaly inorganic filler were 50 or more arbitrarily selected (c) scaly as in the case of the fibrous inorganic filler. It can be measured and calculated by performing image analysis on the inorganic filler with a digital microscope.
The scaly inorganic filler (c) for measurement can be collected from the obtained residue by putting a thin portion of the molded product in an electric furnace and incinerating the contained organic matter.

The (c) scaly inorganic filler may be surface-treated as in (b) the fibrous inorganic filler for the purpose of improving the affinity with the resin component.
Further, when (c) glass flakes are used as the scaly inorganic filler, it is preferable that the glass flakes further contain a sizing agent.

The content of the (c) scaly inorganic filler in the thin portion of the present embodiment is not particularly limited, but is 5 to 30% by mass with respect to 100% by mass of the resin composition contained in the thin portion. , More preferably 10 to 25% by mass, and even more preferably 10 to 20% by mass.
By setting the content to 5% by mass or more, it is possible to provide a molded product having excellent flatness. Further, by setting the content to 30% by mass or less, excellent mechanical properties can be maintained.

[Other materials constituting the resin composition]
The resin composition contained in the thin portion of the molded product of the present embodiment may optionally contain other materials other than the above-mentioned component (a), component (b), and component (c).

〔〔Flame retardants〕〕
The resin composition contained in the thin portion of the molded product of the present embodiment may contain a flame retardant. As the flame retardant for improving the flame retardancy, a flame retardant added to a normal thermoplastic resin can be used, but it is preferable to add a halogen-free organic phosphorus-based flame retardant.

Examples of the organic phosphorus-based flame retardant include phosphoric acid ester-based compounds and phosphazene-based compounds.

The phosphoric acid ester compound is added to improve the flame retardancy of the resin composition, and any organic phosphoric acid ester compound generally used as a flame retardant can be used.

Specific examples of the phosphate ester compound include triphenyl phosphate, trisnonylphenyl phosphate, resorcinolbis (diphenylphosphate), resorcinolbis [di (2,6-dimethylphenyl) phosphate], 2,2-bis {4-. Examples thereof include [bis (phenoxy) phosphoryloxy] phenyl} propane and 2,2-bis {4- [bis (methylphenoxy) phosphoryloxy] phenyl} propane, but the present invention is not limited thereto. Further, as phosphorus-based flame retardants other than the above, for example, trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, tricresyl phosphate, cresylphenyl phosphate, octyldiphenyl phosphate, diisopropylphenyl phosphate and the like. Organophosphate flame retardant, diphenyl-4-hydroxy-2,3,5,6-tetrabromobenzylphosphonate, dimethyl-4-hydroxy-3,5-dibromobenzylphosphonate, diphenyl-4-hydroxy- 3,5-Dibromobenzyl phosphate, tris (chloroethyl) phosphate, tris (dichloropropyl) phosphate, tris (chloropropyl) phosphate, bis (2,3-dibromopropyl) -2,3-dichloropropyl phosphate, tris ( 2,3-Dibromopropyl) phosphate, and bis (chloropropyl) monooctyl phosphate Hydroquinonyldiphenyl phosphate, monophosphate ester compounds such as phenylnonylphenylhydroquinonyl phosphate, phenyldinonylphenyl phosphate, and bisphenol A. bis ( Examples thereof include aromatic condensed phosphoric acid ester compounds such as diphenyl phosphate).
Of these, aromatic condensed phosphoric acid ester compounds are preferably used because they generate less gas during processing and are excellent in thermal stability and the like.

As the aromatic condensed phosphoric acid ester compound that can be used in the present embodiment, the aromatic condensed phosphoric acid ester compound represented by the following general formula (I) or the following general formula (II) is preferable. Particularly preferred is an aromatic condensed phosphoric acid ester compound represented by the following general formula (I).

（一般式（Ｉ）および（ＩＩ）中、Ｑ１、Ｑ２、Ｑ３およびＱ４は、各々置換基であって各々独立に炭素数１から６のアルキル基を表し、Ｒ１１およびＲ１２は各々メチル基を表し、Ｒ１３およびＲ１４は各々独立に水素原子またはメチル基を表し、ｎは１以上の整数であり、ｎ１およびｎ２は各々独立に０から２の整数を示し、ｍ１、ｍ２、ｍ３およびｍ４は各々独立に０から３の整数を示す。）
上記一般式（Ｉ）または（ＩＩ）で示される縮合リン酸エステル化合物は、それぞれの分子において、ｎは、好ましくは１から３の整数である。

(In the general formulas (I) and (II), Q1, Q2, Q3 and Q4 are substituents and each independently represents an alkyl group having 1 to 6 carbon atoms, and R11 and R12 each represent a methyl group. , R13 and R14 each independently represent a hydrogen atom or a methyl group, n is an integer of 1 or more, n1 and n2 each independently represent an integer of 0 to 2, and m1, m2, m3 and m4 are independent of each other. Indicates an integer from 0 to 3.)
In the condensed phosphate compound represented by the general formula (I) or (II), n is preferably an integer of 1 to 3 in each molecule.

The condensed phosphoric acid ester compound represented by the general formula (I) or (II) is preferably the condensed phosphoric acid ester compound represented by the general formula (I), and is m1, m2, m3, m4 in the formula (I). , N1 and n2 are zero and R13 and R14 are methyl groups, or Q1, Q2, Q3, Q4, R13 and R14 in formula (I) are methyl groups, and n1 and n2. A condensed phosphate compound in which m1, m2, m3 and m4 are integers of 1 to 3 and n is an integer of 1 to 3 (particularly preferably n is 1). It is preferable that the acid ester compound contains 50% by mass or more.

These aromatic condensed phosphoric acid ester compounds are generally commercially available, and for example, CR741, CR733S, PX200 manufactured by Daihachi Chemical Industry Co., Ltd., FP600, FP700, FP800 manufactured by ADEKA Corporation, and the like are known. There is.

Particularly preferable among these aromatic condensed phosphoric acid ester compounds are aromatic condensed phosphoric acid ester compounds having an acid value (value obtained in accordance with JIS K2501) of 0.1 or less from the viewpoint of thermal stability. is there.

Further, as the phosphazene compound, phenoxyphosphazene and a crosslinked product thereof are preferable, and phenoxy having an acid value (value obtained in accordance with JIS K2501) of 0.1 or less is particularly preferable from the viewpoint of thermal stability. It is a phosphazene compound.

The content of the flame retardant varies depending on the required flame retardant level, but is preferably in the range of 5 to 30% by mass, more preferably 10 to 25% by mass, based on 100% by mass of the resin composition of the thin portion. The range. When the content of the flame retardant is 5% by mass or more, the flame retardancy of the resin composition is excellent, and when it is 30% by mass or less, the flame retardancy of the resin composition is sufficient and exceeds 30% by mass. And reduces the heat resistance of the resin composition.

[[Hydrogenated copolymer]]
The resin composition of the thin portion of the molded product of the present embodiment is water obtained by hydrogenating a block copolymer having a coupling structure and consisting of a conjugated diene monomer unit and a vinyl aromatic monomer unit. A hydrogenated random copolymer block obtained by hydrogenating a non-hydrogenated random copolymer block which is a copolymer and is composed of a conjugated diene monomer unit and a vinyl aromatic monomer unit. It is possible to contain a hydrogenated copolymer having (hereinafter, also simply referred to as “hydrogenated copolymer”). When the resin composition contains a hydrogenated copolymer, the mechanical strength can be improved.

The content of the hydrogenated copolymer is preferably 10 to 30% by mass, more preferably 10 to 20% by mass, based on 100% by mass of the resin composition of the thin portion. By setting the content to 10% by mass or more, the mechanical strength can be improved. Further, by setting the content to 30% by mass or less, the mechanical strength can be balanced.

In particular, when (a) the amorphous resin is a polyphenylene ether-based resin, if the hydrogenated copolymer is contained as a resin component, the effect of improving the vibration damping property is enhanced, and the flame retardancy is also increased. It becomes easier to give.

[[Other additives]]
In the resin composition of the thin portion of the present embodiment, in addition to the various materials described above, various additives added to a normal thermoplastic resin as needed, such as a heat stabilizer, an ultraviolet absorber, and a mold release agent, are used. , Lubricants, dyes, pigments and the like may be contained.
The content of the other additives is preferably 5% by mass or less with respect to 100% by mass of the resin composition of the thin portion.

The content of the resin composition of the thin portion of the present embodiment is preferably 80% by mass or more, particularly preferably 100% by mass, with respect to 100% by mass of the thin portion.

[Manufacturing method of resin composition]
The resin composition used in this embodiment is preferably obtained by melt-kneading the raw material components with an extruder. The conditions for melt-kneading can be appropriately adjusted depending on the type of resin used, but the extruder used in this embodiment is preferably a twin-screw extruder that rotates in a different direction or rotates in the same direction.
The configuration of the extruder is not particularly limited, but it is preferable to have a device (side feed) capable of adding a material in the middle of the extruder, and it is more preferable to have a plurality of devices (side feeds). For example, with respect to the flow direction of the raw material, the first raw material supply port is located upstream, the first vacuum vent is located downstream of the first raw material supply port, and the second raw material supply port (side feed) is located downstream of the first vacuum vent. (If necessary, third and fourth raw material supply ports may be further provided downstream of the second raw material supply port), and a second vacuum vent is further provided downstream of the second raw material supply port. Is preferable. In particular, a kneading section is provided upstream of the first vacuum vent, a kneading section is provided between the first vacuum vent and the second raw material supply port, and between the second to fourth raw material supply ports and the second vacuum vent. Those provided with a kneading section are more preferable.

As a method of blending the raw material components of the resin composition used in the present embodiment, (a) an amorphous resin is added from the first raw material supply port on the upstream side of the extruder, and (b) a fibrous inorganic filler, ( c) A method of adding the scaly inorganic filler from the second raw material supply port (side feed) is preferable. By this method, it is possible to suppress the pulverization of (b) the fibrous inorganic filler and (c) the scaly inorganic filler, and it is possible to suppress the decrease in the effect of the inorganic filler on preventing deformation of the molded product. ..

Further, it is preferable to adjust the barrel temperature, the screw rotation speed, the discharge amount, and the like so that the resin temperature at the time of melt-kneading can be adjusted in the range of 220 to 330 ° C. By melt-kneading in such a method, the kneadability can be improved and the deterioration of the resin can be suppressed.

[Manufacturing method of molded product]
The thin portion of the molded product of the present embodiment can be molded by a conventionally known method using the above-mentioned resin composition. For example, it can be molded by a known method such as injection molding, injection press molding, gas injection molding, or compression molding.
Further, when the entire molded body of the present embodiment is molded using the above-mentioned resin composition, it can be molded by a known method such as injection molding, injection press molding, gas injection molding, compression molding or the like.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.
First, the raw materials used in Examples and Comparative Examples are shown.

[(A) Amorphous resin]
<I> Polyphenylene ether resin (PPE)
Poly (2,6-dimethyl-1,4-phenylene) ether <ii> high-impact polystyrene resin (HIPS) having an intrinsic viscosity of 0.52 (30 ° C., in chloroform) and a crystallization enthalpy of 0 J / g.
High-impact polystyrene CT60 (manufactured by Petrochemicals), crystallization enthalpy: 0 J / g
<Iii> Polystyrene resin (GPPS)
PSJ Polystyrene 685 (manufactured by PS Japan Corporation), Crystallization enthalpy: 0J / g

[(B) Fibrous inorganic filler]
<I> Glass fiber ECS03T-249 (manufactured by Nippon Electric Glass Co., Ltd., average fiber diameter D: 13 μm, average fiber length L: 3000 μm, aspect ratio (L / D): 231)

[(C) Scale-like inorganic filler]
<I> Glass flakes Micro glass flakes REFG-315 (manufactured by Nippon Sheet Glass, aspect ratio (L1 / L2): approx. 1)
<Ii> Mica Suzolite Mica 200KI (manufactured by Kuraray Co., Ltd., aspect ratio (L1 / L2): approx. 1)
<Iii> Talc RGE-250 (manufactured by Fuji Talc Industry Co., Ltd., aspect ratio (L1 / L2): approx. 1)

[(D) Flame Retardant]
Bisphenol A / Bis (diphenyl phosphate) (BDP) (Product name: E890 (
Registered trademark), manufactured by Daihachi Chemical Industry)

《Test and evaluation》
Tests and evaluations were carried out by the following methods using the test pieces prepared in Examples and Comparative Examples.

<I> Warp deformation ISO-A dumbbell (total length 170 mm, parallel part width 10 mm, parallel part length 80 mm, thickness 4 mm) test piece and ISO-A except that the thickness is 2 mm and 3 mm, respectively. The flatness was measured for a total of three types of test pieces having the same shape as the dumbbell, and the warp deformation was evaluated according to the following criteria. The flatness was measured using a 3D microscope (“VR-3200”, manufactured by KEYENCE CORPORATION, condition: 10 points on the end surface on the extension of the parallel portion of the test piece were measured). The sample table was used as a reference plane, and the difference between the maximum value and the minimum value of 10 measurement points was defined as flatness x (μm).
(Evaluation criteria)
◎ (excellent): x ≦ 170 μm.
◯ (possible): 170 μm <x ≦ 210 μm.
X (defective): 210 μm <x.

<Ii> Dimensional change ISO-A except for the test piece of ISO-A dumbbell (total length 170 mm, width of parallel part 10 mm, length of parallel part 80 mm, thickness 4 mm) and the thickness of 2 mm and 3 mm, respectively. The dimensions of a total of three types of test pieces having the same shape as the dumbbell were measured, and the dimensional change was evaluated according to the following criteria. The dimension (longitudinal length) of the test piece was measured using a 3D scope (“VR-3200”, manufactured by KEYENCE CORPORATION, condition: measuring the total length in the longitudinal direction of the central part of the test piece). The difference between the size of the test piece immediately after molding and the size of the test piece after 72 hours was determined and used as the dimensional change y (μm).
(Evaluation criteria)
◎ (excellent): y ≦ 5 μm.
◯ (possible): 5 μm <y ≦ 10 μm.
X (defective): 10 μm <y.

[Examples 1 to 3 and Comparative Examples 1 to 2]
(Preparation of resin composition pellets)
Melt each component using a twin-screw extruder (“ZSK-40”, manufactured by WENER & PFLIDERE) in which the barrel temperature is set to 290 to 320 ° C., the screw rotation speed is set to 500 rpm, and the discharge rate is set to 670 kg / hour according to the compounding composition shown in Table 1. The mixture was kneaded to obtain resin composition pellets. In the twin-screw extruder, a first raw material supply port is provided on the upstream side with respect to the flow direction of the raw material, a first vacuum vent and a second raw material supply port (side feed) are provided downstream of the first raw material supply port, and further downstream thereof. A second vacuum vent was provided. The component (a) was supplied from the first raw material supply port, and the components (b), (c), and (d) were supplied from the second raw material supply port.

(Preparation of test piece)
Using the resin composition pellets obtained above, injection molding was performed under the conditions of a cylinder temperature of 280 to 300 ° C. and a mold temperature of 60 to 80 ° C., and an ISO-A dumbbell (total length 170 mm, parallel portion width 10 mm). A total of three types of test pieces were prepared: a test piece having a parallel portion (length 80 mm and a thickness of 4 mm) and a test piece having the same shape as the ISO-A dumbbell except that the thickness was 2 mm and 3 mm, respectively.
Table 1 shows the evaluation results of Examples and Comparative Examples.

According to the present invention, it is possible to provide a molded product in which warpage deformation and dimensional change are reduced, and it can be suitably used for parts for electronic devices and the like.

Claims (6)

It has a thin portion having an average thickness of 3 mm or less and a length in the longitudinal direction that is four times or more the length in the lateral direction orthogonal to the longitudinal direction.
The thin portion is (a) an amorphous resin, (b) a fibrous inorganic filler having an aspect ratio (L / D) of 8 or more between the average fiber length L and the average fiber diameter D, and (c). A molded product comprising a resin composition containing a scaly inorganic filler having an aspect ratio (L1 / L2) of an average major axis L1 and an average minor axis L2 of 3 or less. The molded product according to claim 1, wherein the amorphous resin (a) is a polyphenylene ether-based resin. Ratio of the content of the (c) scaly inorganic filler in the resin composition to the content of the (b) fibrous inorganic filler in the resin composition ((c) component / (b) component ) Is 0.4 to 2.0, according to claim 1 or 2. The molded product according to any one of claims 1 to 3, wherein the fibrous inorganic filler (b) is glass fiber. The molded product according to any one of claims 1 to 4, wherein the (c) scaly inorganic filler is mica. The molded product according to any one of claims 1 to 5, wherein the thin portion is formed by injection molding.