JP2002235010A - Exterior part for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exterior part for a vehicle having excellent conductivity, heat resistance, shock resistance, size stability and surface appearance of a molded product at the same time, and obtainable by molding a thermoplastic resin composition. SOLUTION: The exterior part is obtained from a thermoplastic resin composition comprising (A) 100 pts.wt. of a resin composition consisting of (a) 55-97 wt.% of a thermoplastic resin and (b) 3-45 wt.% of a shock resistance-improving agent, (B) 3-60 pts.wt. of graphite having an average particle size of 1-70 μm and (C) 3-30 pts.wt. of an antistatic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a heat treatment for providing a molded article having conductivity, heat resistance, impact resistance, dimensional stability and good surface appearance of the molded article which are particularly suitable for application to exterior parts of automobiles. The present invention relates to a vehicle exterior part obtained by molding a plastic resin composition.

[0002]

2. Description of the Related Art In recent years, with increasing awareness of environmental issues, weight reduction has been more actively promoted than ever before in order to improve fuel efficiency of automobiles. As one example, the replacement of metal materials for exterior parts with resin materials has become active. The characteristics required for exterior parts include heat resistance to withstand painting processes such as online painting and in-line painting, impact resistance to withstand the impact of collisions, dimensional stability with small dimensional changes due to heat, and class A surface appearance. Has conventionally been required. In recent years, for the purpose of improving productivity and coating quality, resin exterior parts have been required to have electrical conductivity that enables on-line coating similarly to metal exterior parts.

As a method for improving the impact resistance of a molded article, a method of incorporating an impact resistance improving agent such as a thermoplastic elastomer is known. However, when such a component is used, heat resistance and dimensional stability are reduced. There was a problem to do.

On the other hand, a method of incorporating a fibrous or non-fibrous filler in order to improve heat resistance and dimensional stability is known. However, when such a component is used, impact resistance is lowered, and additional When a fibrous filler is used as the filler, the fibrous filler protrudes from the surface of the molded product, which causes a problem of deteriorating the surface appearance of the molded product.

Accordingly, the present inventors have disclosed in Japanese Patent Application No. 2000-286211 a resin composition having simultaneously sufficient impact resistance, heat resistance, dimensional stability and surface appearance, a polyamide resin, an impact modifier, A composition consisting of a specific talc was proposed. However, the present invention does not consider the conductivity.

As a method of imparting conductivity to a thermoplastic resin, a method of adding carbon black is most generally known. However, when carbon black is added to a thermoplastic resin, impact resistance, fluidity, and the like are significantly reduced. Also, as conductive particles other than carbon black,
Methods of adding graphite and metal particles are also being studied. However, when graphite or metal particles are used, there is a problem that impact resistance is reduced.

Therefore, an invention in which an effect is exhibited by a small amount of conductive particles is disclosed in JP-A-62-24749 and JP-A-2-4749.
It is disclosed in JP-A-113068. In the present invention, the conductive particles are unevenly distributed in the sea phase in the multi-component thermoplastic resin matrix forming the sea-island structure, and the amount added is reduced. However, although a decrease in impact resistance is suppressed to some extent, it is not possible to obtain a molded article having sufficient heat resistance and dimensional stability.

In Japanese Patent Application Laid-Open No. 2001-2896, carbon fibers or graphite are used as conductive particles.
Further, a composition containing an elastomer for improving impact resistance has been proposed. However, when carbon fiber is used, the surface appearance deteriorates, and it is necessary to add a large amount to provide conductivity only with graphite. As a result, even if an elastomer is added, impact resistance is reduced. However, there is a problem that the liquidity is not sufficient and the liquidity is greatly reduced.

Thus, the conductivity, heat resistance, impact resistance,
A vehicle exterior component molded from a resin composition having characteristics such as dimensional stability and surface appearance has not yet been obtained.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to form a thermoplastic resin composition which gives excellent molded products by balancing the conductivity, heat resistance, impact resistance, dimensional stability, and surface appearance of the molded products. To provide a vehicle exterior part obtained by the above method.

[0011]

Means for Solving the Problems The above problems are mainly
(A) Resin composition 100 comprising (a) 55 to 97% by weight of a thermoplastic resin and (b) 3 to 45% by weight of an impact modifier.
Parts by weight and (B) graphite 3 having an average particle size of 1 to 70 μm
This is achieved by providing a vehicle exterior part obtained by molding a thermoplastic resin composition comprising from 60 to 60 parts by weight and (C) 3 to 30 parts by weight of an antistatic resin.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The thermoplastic resin (a) used in the present invention is not particularly limited as long as it is a resin that can be melt-molded, and may be either a crystalline resin or an amorphous resin.
Such thermoplastic resins include, for example, polypropylene, polyethylene, polystyrene, polyvinyl chloride, polyvinyl acetate, ABS resin, AS resin, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyamideimide, polyacetal, polycarbonate, modified polyphenylene oxide, polyvinyl Examples include alcohol, polyalkylene oxide, polysulfone, polyphenylene sulfide, polyarylate, polyetherimide, polyetheretherketone, polyethersulfone, polyimide, liquid crystal polymer, polymethylmethacrylate, and polysulfone.

Above all, it is preferable to use a crystalline thermoplastic resin having a melting point of 200 ° C. or more, since a molded article having excellent heat resistance can be obtained. In particular, a polyamide resin and / or a polyester resin is preferably used, and more preferably a polyamide resin, since a molded article having excellent physical properties such as heat resistance and strength can be obtained.

Here, the polyamide resin is a polyamide obtained by using aminocarboxylic acid, lactam, or diamine and dicarboxylic acid as main components. Typical examples of the main components are 6-aminocaproic acid and 11-amino acid. Aminocarboxylic acids such as aminoundecanoic acid, 12-aminododecanoic acid and paraaminomethylbenzoic acid, lactams such as ε-caprolactam and ω-laurolactam, tetramethylenediamine, hexamethylenediamine, 2-methylpentamethylenediamine, nonamethylenediamine , Undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, meta-xylylenediamine, para-xylylenediamine, 1,3-bis (amino Methyl) cyclohexane,
1,4-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane , 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine, and other aliphatic, alicyclic and aromatic diamines, and adipic acid, suberic acid, azelaic acid, sebacic acid , Dodecane diacid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, aliphatics such as hexahydroisophthalic acid, Alicyclic and aromatic dicarboxylic acids are exemplified. In the present invention, polyamide homopolymers or copolymers derived from these components can be used alone or in combination of two or more.

It is a preferred embodiment to use a crystalline polyamide resin having a melting point of 200 ° C. or higher.
Specific examples thereof include polycaproamide (nylon 6) and polyhexamethylene adipamide (nylon 6
6), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6/66), polytetramethylene adipamide (nylon 46), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon) 612), polyhexamethylene terephthalamide / polycaproamide copolymer (nylon 6
T / 6), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 /
6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66/6
I), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I),
Polyhexamethylene terephthalamide / polydodecaneamide copolymer (nylon 6T / 12), polyhexamethylene terephthalamide / poly (2-methylpentamethylene) terephthalamide copolymer (nylon 6T / M
5T), polyxylylene adipamide (nylon XD
6), polynonamethylene terephthalamide (nylon 9
T), and mixtures or copolymers thereof.

Particularly preferred polyamide resins include nylon 6, nylon 66, nylon 610, nylon 6/66 copolymer, nylon 6T / 66 copolymer, nylon 6T / 6I copolymer, nylon 6T / 1
2 copolymer and nylon 6T / 6 copolymer, and it is also preferable to use these polyamide resins as a mixture depending on required properties such as impact resistance, moldability and compatibility.

The degree of polymerization of the polyamide resin is not particularly limited as long as it has moldability. The relative viscosity of a solution of 1% by weight of the polyamide resin in 98% concentrated sulfuric acid measured at 25 ° C. is 1. In the range of 5 to 5.0, especially 2.0 to 4.
It is preferable to use those in the range of 0.

The above polyester resin is a polymer having an ester bond in the main chain. Specifically, usually
Aromatic dicarboxylic acids (or their ester-forming derivatives) and diols (or their ester-forming derivatives)
And / or hydroxycarboxylic acid as a main component,
A polymer or copolymer obtained by a condensation reaction is exemplified.

Specific examples of the polyester preferably used include polyalkylene terephthalate such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polycyclohexane dimethylene terephthalate, polyhexylene terephthalate, polyethylene-2,6-naphthalenedicarboxylate, and the like. Polybutylene-2,6-naphthalenedicarboxylate, polyethylene-1,2-bis (phenoxy) ethane-4,4'-dicarboxylate, polyethylene isophthalate / terephthalate, polybutylene isophthalate / terephthalate, polybutylene terephthalate / Decanedicarboxylate, poly (ethylene terephthalate / cyclohexane dimethylene terephthalate), polyethylene -4,4'-dicarboxylate /
Non-liquid crystalline polyesters such as terephthalate and mixtures thereof.

Particularly preferred are polybutylene terephthalate, polyethylene terephthalate, and polyethylene-2,6-naphthalenedicarboxylate. These polyester resins have properties required for molding, heat resistance, toughness, surface properties and the like. Accordingly, it is practically preferable to use it as a mixture.

The degree of polymerization of the polyester resin is not particularly limited. For example, in the case of polybutylene terephthalate, the intrinsic viscosity measured at 25 ° C. in a 0.5% by weight o-chlorophenol solution is from 0.36 to 0.36. 3.00 range,
Particularly, those having a range of 0.50 to 2.00 are preferable. 0.5% by weight for polyethylene terephthalate
Of phenol / tetrachloroethane in a 1: 1 solvent mixture at 25 ° C.
To 3.00, particularly preferably 0.40 to 2.25.

The carboxy terminal group content of the polyester resin is, for example, in the case of a polybutylene terephthalate resin, a value obtained by potentiometric titration of an m-cresol solution with an alkali solution, from 1 to 50 equivalents / t (per ton of polymer). Are in the range of (end group amount of).
Further, the anisotropy is preferably used because it is suppressed.

In the present invention, the resin composition of the component (A) contains 55 to 97% by weight of the thermoplastic resin (a) described above,
(B) It contains 3 to 45% by weight of an impact modifier. The proportion of the thermoplastic resin (a) is preferably 55 to 90% by weight. If it is less than 55% by weight, heat resistance is poor. Also,
If it exceeds 97% by weight, the impact resistance is poor.

In the present invention, other resins such as an antistatic resin are contained as described later. However, since a molded article having excellent heat resistance is easily obtained, it occupies the thermoplastic resin composition of the present invention. The proportion of the thermoplastic resin of the component (a) is preferably at least 35% by weight, more preferably at least 40% by weight, particularly preferably at least 45% by weight, based on the whole resin component. The upper limit is not particularly limited, but is about 94% by weight.

The impact modifier used in the present invention is:
(A) A component that improves impact resistance when alloyed with the thermoplastic resin of the component, and includes, for example, a (co) polymer obtained by polymerizing an olefin compound and / or a conjugated diene compound. .

Examples of the above (co) polymer include an ethylene copolymer, a conjugated diene polymer, and a conjugated diene-aromatic vinyl hydrocarbon copolymer.

Here, the ethylene-based copolymer means a copolymer of ethylene and another monomer and a multi-component copolymer, and the other monomer copolymerized with ethylene has 3 carbon atoms.
It can be selected from the above α-olefins, non-conjugated dienes, vinyl acetate, vinyl alcohol, α, β-unsaturated carboxylic acids and derivatives thereof.

As the α-olefin having 3 or more carbon atoms,
Examples thereof include propylene, butene-1, pentene-1, 3-methylpentene-1, and octacene-1, and propylene and butene-1 can be preferably used. Non-conjugated dienes include 5-methylidene-2-norbornene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-propenyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-crotyl -2-norbornene, 5- (2-methyl-2-butenyl) -2-norbornene, 5- (2-ethyl-2-butenyl) -2-
Norbornene compounds such as norbornene and 5-methyl-5-vinylnorbornene, dicyclopentadiene, methyltetrahydroindene, 4,7,8,9-tetrahydroindene, 1,5-cyclooctadiene 1,4-hexadiene, isoprene, 6 -Methyl-1,5-heptadiene, 11-tridecadiene and the like, and preferably 5-methylidene-2-norbornene, 5-ethylidene-2-norbornene, dicyclopentadiene, 1,4-
Hexadiene and the like. Examples of the α, β-unsaturated carboxylic acid include acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and butenedicarboxylic acid. Esters, glycidyl esters, acid anhydrides, imides can be mentioned as examples.

The conjugated diene-based polymer is a polymer containing at least one kind of conjugated diene as a constituent component.
For example, a homopolymer such as 1,3-butadiene or 1,3-butadiene
Butadiene, isoprene (2-methyl-1,3-butadiene), 2,3-dimethyl-1,3-butadiene, 1,
Examples include a copolymer of one or more monomers selected from 3-pentadiene. Those in which some or all of the unsaturated bonds of these polymers are reduced by hydrogenation can also be preferably used.

The conjugated diene-aromatic vinyl hydrocarbon-based copolymer is a block copolymer or a random copolymer consisting of a conjugated diene and an aromatic vinyl hydrocarbon. And 1,3-butadiene and isoprene are particularly preferred.
Examples of the aromatic vinyl hydrocarbon include styrene, α-methyl styrene, o-methyl styrene, p-methyl styrene, 1,3-dimethyl styrene, vinyl naphthalene and the like. Among them, styrene can be preferably used. Further, a conjugated diene-aromatic vinyl hydrocarbon-based copolymer in which some or all of the unsaturated bonds other than the double bond other than the aromatic ring are reduced by hydrogenation can also be preferably used.

Further, in order to finely control the dispersion particle diameter of the impact modifier in the resin composition, various unsaturated carboxylic acids and / or derivatives thereof and vinyl monomers are further subjected to a graft reaction or a copolymerization. (Co) obtained by polymerization
Polymers can also be used preferably. The amount of the unsaturated carboxylic acid and / or its derivative or vinyl monomer which has been graft-reacted or copolymerized with respect to the impact modifier is preferably 0.01 to 20% by weight. Examples of the unsaturated carboxylic acid used for the graft reaction or copolymerization include acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and butenedicarboxylic acid. In addition, as their derivatives, alkyl esters, glycidyl esters, di-
And esters, acid anhydrides or imides having a tri-alkoxysilyl group, among which glycidyl esters, unsaturated carboxylic acid esters having a di- or tri-alkoxysilyl group, acid anhydrides and imides are preferred.

Preferred examples of unsaturated carboxylic acids or derivatives thereof include maleic acid, fumaric acid, glycidyl acrylate, glycidyl methacrylate, diglycidyl itaconate, diglycidyl citraconic ester,
Butenedicarboxylic acid diglycidyl ester, butenedicarboxylic acid monoglycidyl ester, maleic anhydride, itaconic anhydride, citraconic anhydride, maleic imide,
Examples thereof include itaconic imide and citraconic imide, and particularly, glycidyl methacrylate, maleic anhydride, itaconic anhydride, and maleic imide can be preferably used. Examples of the vinyl monomer include an aromatic vinyl compound such as styrene, a vinyl cyanide compound such as acrylonitrile, and a vinylsilane compound such as vinyltrimethoxysilane. Alternatively, two or more vinyl monomers may be used in combination. Known methods can be used for grafting these unsaturated carboxylic acids or their derivatives or vinyl monomers.

Further, a polyamide elastomer or a polyester elastomer can also be used. Two or more of these impact resistance improving materials can be used in combination.

Specific examples of such impact modifiers include ethylene / propylene copolymer, ethylene / butene-1 copolymer, ethylene / hexene-1 copolymer and ethylene / propylene / dicyclopentadiene copolymer. Polymer, ethylene / propylene / 5-ethylidene-2-norbornene copolymer, unhydrogenated or hydrogenated styrene / isoprene /
Styrene triblock copolymer, unhydrogenated or hydrogenated styrene / butadiene / styrene triblock copolymer, ethylene / methacrylic acid copolymer and some or all of the carboxylic acid moiety in these copolymers are sodium, lithium , Potassium, zinc, salt with calcium,
Ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl methacrylate copolymer, ethylene / ethyl methacrylate copolymer, ethylene / ethyl acrylate-g-maleic anhydride copolymer , (“G” represents a graft, the same applies hereinafter), ethylene / methyl methacrylate-g-maleic anhydride copolymer, ethylene / ethyl acrylate-g-maleimide copolymer, ethylene / ethyl acrylate-g- N-phenylmaleimide copolymer and partially saponified products of these copolymers, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer, ethylene / methyl methacrylate / glycidyl methacrylate copolymer, ethylene / Glycidyl acrylate copolymer, d Len / vinyl acetate / glycidyl acrylate copolymer, ethylene / glycidyl ether copolymer, ethylene / propylene-g-maleic anhydride copolymer, ethylene / butene-1-g-maleic anhydride copolymer, ethylene / propylene / 1,4-hexadiene-g-maleic anhydride copolymer, ethylene / propylene / dicyclopentadiene-g-maleic anhydride copolymer, ethylene / propylene / 2,5-norbornadiene-g-maleic anhydride copolymer Coalesce, ethylene / propylene-g-N-phenylmaleimide copolymer, ethylene / butene-1-g-N-phenylmaleimide copolymer,
Hydrogenated styrene / butadiene / styrene-g-maleic anhydride copolymer, hydrogenated styrene / isoprene / styrene-
g-maleic anhydride copolymer, ethylene / propylene-
g-glycidyl methacrylate copolymer, ethylene / butene-1-g-glycidyl methacrylate copolymer, ethylene / propylene / 1,4-hexadiene-g-glycidyl methacrylate copolymer, ethylene / propylene / dicyclopentadiene -G-glycidyl methacrylate copolymer, hydrogenated styrene / butadiene / styrene-g-glycidyl methacrylate copolymer, nylon 12 / polytetramethylene glycol copolymer, nylon 12 / polytrimethylene glycol copolymer, poly Butylene terephthalate / polytetramethylene glycol copolymer, polybutylene terephthalate / polytrimethylene glycol copolymer and the like can be mentioned. Among them, ethylene / methacrylic acid copolymers and some or all of the carboxylic acid moieties in these copolymers are sodium, lithium,
Salts with potassium, zinc and calcium, ethylene / propylene-g-maleic anhydride copolymer, ethylene / butene-1-g-maleic anhydride copolymer, hydrogenated styrene / butadiene / styrene-g- Maleic anhydride copolymers are more preferred, and ethylene / methacrylic acid copolymers and those in which some or all of the carboxylic acid moieties in these copolymers are salts with sodium, lithium, potassium, zinc, calcium, ethylene / Propylene-g
-Maleic anhydride copolymer, ethylene / butene-1-g
-Maleic anhydride copolymers are particularly preferred.

The graphite (B) used in the present invention includes:
There are so-called natural graphites and artificial graphites, and both graphites can be used. These may be used in combination. The graphite may be in the form of flakes, scales, earth, or the like, but is preferably flakes or scales from the viewpoint of heat resistance and dimensional stability.

The thermoplastic resin composition used in the present invention contains graphite having an average particle size of 1 to 70 μm.
Preferably, 3 to 30 μm, more preferably, 5 to 2
0 μm. When the average particle size is less than 1 μm, not only the balance of physical properties such as heat resistance and dimensional stability is insufficient, but also the working environment is deteriorated due to scattering of fine powder, and the production is difficult. If it exceeds 70 μm, the surface appearance deteriorates. As described above, even if carbon black or a general conductivity-imparting agent is used, and graphite is not particularly in a specific particle size range, the conductivity can be improved, and even if the impact resistance is improved. Even if the agent is used in combination, it is not possible to obtain a molded article having sufficient heat resistance, impact resistance, dimensional stability and surface appearance of the molded article.

The average particle size is determined by cutting out a cross section of the resin composition, measuring the longest portion of 100 graphites extracted at random by taking an image using a transmission electron microscope or an optical microscope, and calculating the number average thereof. Can be

The content of the graphite of the component (B) is 3 to 60 parts by weight based on the resin composition (A). If the amount is less than 3 parts by weight, conductivity will not be exhibited, and if it exceeds 60 parts by weight, impact resistance will be insufficient and the surface appearance will be poor.

In the thermoplastic resin composition of the present invention, (B) graphite is present in an amount of 30% or more, more preferably 50% or more in the thermoplastic resin composition of the present invention in (C) an antistatic resin described later. Is preferred. With such a configuration, conductivity can be efficiently improved.

In the present invention, (C) an antistatic resin is mainly contained in order to further improve the antistatic property and conductivity. Here, the antistatic resin refers to a resin having a surface specific resistance of less than 1 × 10 ¹² Ω, and the type thereof is not particularly limited. The (C) antistatic resin has good compatibility and can obtain an antistatic effect and an effect of improving conductivity without impairing other physical properties. Therefore, the polyamide resin and the polyoxyalkylene unit are the main constituents. Polymers are preferred.

The polyamide unit is derived from a salt of an aminocarboxylic acid having 10 or less carbon atoms or a lactam or a diamine having 10 or less carbon atoms and a dicarboxylic acid having 10 or less carbon atoms. Examples of such compounds include aminocarboxylic acids such as 6-aminohexanoic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 9-aminononanoic acid and 10-aminodecanoic acid, lactams such as caprolactam, enantholactam and caprylactam. And ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, 2,2,4- or 2,4,4-triamine Chill hexamethylene diamine, 1,
Aliphatic or alicyclic or aromatic diamine selected from 3- or 1,4-bis (aminomethyl) cyclohexane, meta-xylylenediamine, para-xylylenediamine and the like and adipic acid, suberic acid, sebacic acid, 1,3 -Or 1,4-cyclohexanedicarboxylic acid, isophthalic acid,
Examples thereof include salts composed of aliphatic, alicyclic, and aromatic dicarboxylic acids selected from terephthalic acid and the like, and these can be used alone or in the form of a mixture of two or more. Among these, caprolactam, hexamethylenediamine-adipate, hexamethylenediamine-
Sebacate is particularly preferably used.

Examples of the polyoxyalkylene unit include polyoxyethylene, polyoxypropylene, polyoxytetramethylene, polyoxypentamethylene,
Examples thereof include polyoxyhexamethylene, polyoxyethylene / propylene, and polyoxyethylene / tetramethylene. Among them, polyoxyethylene, polyoxyethylene / propylene, and polyoxyethylene / tetramethylene are preferable.

The number average molecular weight of the polyoxyalkylene component is preferably within a range from 200 to 6000, and is preferably from 250 to 40.
A range of 00 is more preferred. When the number average molecular weight is less than 200, the mechanical properties of the obtained antistatic resin are remarkably inferior,
If the number average molecular weight exceeds 6,000, conductivity is impaired, which is not preferable.

The content of the (C) antistatic resin is 3 to 30 parts by weight, preferably 3 to 20 parts by weight, per 100 parts by weight of the resin composition (A). If the amount exceeds 30 parts by weight, the heat resistance and dimensional stability tend to decrease, although the improvement in the antistatic effect is small.

The thermoplastic resin composition of the present invention preferably contains (D) an inorganic filler. Known inorganic fillers generally used as inorganic fillers for resins are used as the inorganic filler, and can improve the strength, rigidity, heat resistance, dimensional stability and the like of the thermoplastic resin composition of the present invention. For example, fibrous inorganic fillers such as glass fiber, carbon fiber, potassium titanate whisker, zinc oxide whisker, aluminum borate whisker, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, masonry fiber, and metal fiber , Wollastenite, zeolite, sericite, kaolin, mica, clay, pyrophyllite, bentonite, montmorillonite, asbestos, silicates such as aluminosilicate, alumina, silicon oxide, magnesium oxide, zirconium oxide, titanium oxide, iron oxide, etc. Metal oxides, carbonates such as calcium carbonate, magnesium carbonate, and dolomite; sulfates such as calcium sulfate and barium sulfate; hydroxides such as magnesium hydroxide, calcium hydroxide, and aluminum hydroxide; glass beads; and ceramics Over's, boron nitride, non-fibrous inorganic fillers such as silicon carbide and silica. These may be hollow, and it is also possible to use two or more of these inorganic fillers. Further, these inorganic fillers may be used after being treated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound, or an epoxy compound. Also,
As for montmorillonite, an organized montmorillonite obtained by cation exchange of interlayer ions with an organic ammonium salt may be used.

Among these inorganic fillers, it is preferable to use a non-fibrous reinforcing material in terms of excellent surface appearance. Further, among the non-fibrous reinforcing materials, talc is preferable because of excellent dimensional stability and heat resistance. The talc preferably has an average particle size of 0.5 to 7 μm, and
Is more preferred. In the case of talc having an average particle diameter of less than 0.5 μm, aggregation tends to occur and the impact resistance may be poor. Also, talc having an average particle size of more than 7 μm may have poor impact resistance. The average particle size is a number average particle size that can be determined as a 50% integrated value of the particle size measured by a laser diffraction method.

The content of the inorganic filler (D) contained in the thermoplastic resin composition used in the present invention is as follows:
The amount is preferably 5 to 60 parts by weight, more preferably 10 to 50 parts by weight, based on 0 parts by weight. Within such a range, the balance between heat resistance, impact resistance and dimensional stability will be further improved. If it exceeds 60 parts by weight, impact resistance may be reduced.

The thermoplastic resin composition used in the present invention includes:
Other components such as antioxidants and heat stabilizers (such as hindered phenols, hydroquinones, phosphites and derivatives thereof) within a range not to impair the object of the present invention;
Weathering agents (resorcinol, salicylate, benzotriazole, benzophenone, hindered amine, etc.), release agents and lubricants (montanic acid and its metal salts, esters, half esters, stearyl alcohol, stearamide, various bisamides, bis Urea and polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.), dyes (nigrosine, etc.), crystal nucleating agents (talc, silica, kaolin, clay, etc.), plasticizers (octyl p-oxybenzoate, N -Butylbenzenesulfonamide, etc.), antistatic agents (alkyl sulfate type anionic antistatic agents, quaternary ammonium salt type cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine) Amphoteric charging Blocking agents, etc.), conductive particles (metal fine particles, carbon black, etc.), flame retardants (eg, red phosphorus, melamine cyanurate, magnesium hydroxide, hydroxides such as aluminum hydroxide, ammonium polyphosphate, brominated polystyrene, Contains brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resin or a combination of these brominated flame retardants with antimony trioxide), a coloring inhibitor (such as hypophosphite), and other polymers Can be.

Next, a method for obtaining the thermoplastic resin composition used in the present invention will be described with reference to examples. The thermoplastic resin composition of the present invention can be obtained by melt-kneading each component by a known kneading method. As the kneading method, either a batch method or a continuous method can be adopted, but the continuous method is preferable in terms of productivity. Examples of the kneading apparatus include single-screw and twin-screw extruders, kneaders, kneaders, and the like, but are not particularly limited. Twin screw extruders are preferred in terms of productivity and the like. When an extruder is used, (1) a method in which each raw material is supplied to the extruder collectively, or (2) a plurality of arbitrary components are melt-kneaded in advance, pelletized, and the remaining components are extruded. To the machine.
(3) When using an extruder having two or more supply ports, one or more arbitrary components are supplied from the first (upstream) supply port, and the second and subsequent (downstream side) are supplied. A) The remaining optional one or more components may be supplied from a supply port. From the viewpoint of productivity, the method (3) is preferable. In particular, in the methods (2) and (3), (C)
When the antistatic resin of the component is used, a method of previously melting and kneading the antistatic resin of the component (C) and the graphite of the component (B), or a method of supplying both components from the first supply port. Is preferred. In particular, the (C) component antistatic resin and (B)
It is preferable to first melt-knead or supply the mixture from the first supply port with only two components of graphite.

As a method for molding the thermoplastic resin composition used in the present invention, a known method can be used.
For example, extrusion molding, injection molding, injection compression molding, blow molding, press molding and the like, and are not particularly limited,
Injection molding and injection compression molding are preferred in terms of productivity and the like.

The vehicle exterior part of the present invention is obtained by molding the above-mentioned thermoplastic resin composition, and specifically includes a fuel lid, a bumper, a front fender, a rear fender, a door panel, and a tailgate. Panels, licensed garnishes, bonnets, trunk lids, etc. In particular, vehicle exterior parts such as front fenders, rear fenders, door panels, and tailgate panels are useful.

[0052]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. The evaluation methods used in the examples are as follows.

A. Dimensional stability: Coefficient of linear expansion at 30 to 80 ° C. Using TMA100 manufactured by SEIKO Electronics Co., Ltd., cut out from the square plate or near the center of the fuel lid and 3 × 3 ×
A test piece prepared to a size of 10 mmh is
It was determined from the dimensional change when the temperature was raised to 2 ° C at a rate of 2 ° C / min.

B. Conductivity: surface resistivity ULTRA MEGOHMMETER manufactured by Toa Denpa Kogyo
Using model SM-10E, applied voltage 500
In V, the surface resistivity of the square plate was measured.

C. Surface appearance: visually When the surface of each prepared plate or test piece had conspicuous irregularities, x was given; when there was no problem, ○ was given;

D. Impact resistance: Notched Izod impact strength Using a Toyo Seiki Izod impact strength tester, thickness 1
ASTM D256-87 using a / 8 inch sample
It was measured according to.

E. Heat resistance: Deflection temperature under load under a load of 0.46 MPa Using HDT-TESTER manufactured by Toyo Seiki Co., Ltd., height 1 /
Using a 2 inch, 1/4 inch wide sample, ASTM
It was measured according to D648-82.

Examples 1 to 11 and Comparative Examples 1 to 16 The following materials were blended in the proportions shown in Tables 1 to 4, melt-kneaded by a twin screw extruder TEX-30 manufactured by Nippon Steel Works, and pelletized.

A. Materials used Polyamide resin (thermoplastic resin 1): "Amilan" CM
1001 (Product No. CM1007) (manufactured by Toray Industries, Inc.) Polyester resin (thermoplastic resin 2): PBT1100
S (product No. 1401-X07) (manufactured by Toray Industries, Inc.) Impact modifier 1: "Himilan" 1706 (manufactured by DuPont-Mitsui Polychemicals) Impact modifier 2: "N-Tuffmer" MH5020 (Mitsui Chemicals) Antistatic resin: 60 parts by weight of epsilon caprolactam, 40 parts by weight of polyethylene glycol having an average molecular weight of 400, and a mixture of adipic acid equivalent to the terminal group amount of the polyethylene glycol are charged into a pressure-reduced melt polymerization vessel and stirred. The N6 / PEG copolymer having a melting point of 179 ° C. was obtained by melt-pressure polymerization. This sample was injection molded, and the surface resistivity measured by the following method was 10 ¹¹ Ω. Graphite 1: Graphite 3243 (Asbury
Graphite Mills), average particle size 50
μm Graphite 2: BF-5A (manufactured by Chuetsu Graphite), average particle size: 5 μm Graphite 3: graphite (manufactured by Katayama Chemical), average particle size: 200 μm Carbon black: # 3030B (manufactured by Mitsubishi Chemical Corporation) Talc: average particle size: 4.5 μm Talc 2: NK48 (manufactured by Fuji Talc), average particle size: 24 μm Glass fiber: T258DE (manufactured by NEC Corporation).

In Example 3, the antistatic resin and graphite were supplied from the first supply port, and the other raw materials were supplied from the second supply port. Otherwise, all raw materials were supplied from the first supply port, and were melt-kneaded and then pelletized.

In Example 7, the obtained pellets were
Hot air drying was performed at 8 ° C. for 8 hours. Otherwise, the obtained pellets were vacuum dried at 80 ° C. for 12 hours. Using the dried pellets, a test piece and an 80 × 80 × 3 mm square plate were formed using an injection molding machine SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd. The impact resistance, dimensional stability, conductivity, surface appearance, and heat resistance were evaluated.

In Examples 2 and 3, the proportion of graphite present in the antistatic resin was determined using a transmission electron microscope.

A fuel lid of 14 cm × 16 cm × 3 mm was formed from the material of Example 5 using an injection molding machine. The surface appearance of the obtained fuel lid was evaluated. Further, a sample was cut out from the vicinity of the center of the fuel lid, and dimensional stability was evaluated. The coefficient of linear expansion was 5.2 × 10 ⁻⁵ / ° C. In addition, it was confirmed that it had an extremely excellent appearance.

[0064]

[Table 1]

[0065]

[Table 2]

[0066]

[Table 3]

[0067]

[Table 4]

[0068]

According to the present invention, a vehicle obtained by molding a thermoplastic resin composition which gives an excellent molded product by balancing the conductivity, heat resistance, impact resistance, dimensional stability and surface appearance of the molded product. Exterior parts can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 67/02 C08L 67/02 77/00 77/00 // (C08L 67/02 (C08L 67/02 101 : 00 101: 00 77:12) 77:12) (C08L 77/00 (C08L 77/00 101: 00 101: 00 77:12) 77:12) (C08L 101/00 (C08L 101/00 77:12) ) 77:12) F-term (reference) 3D003 AA01 AA05 BB01 CA55 4J002 AA011 BB031 BB052 BB072 BB082 BB102 BB121 BB152 BB212 BB232 BC031 BC061 BD041 BF021 BG061 BN032 BN061 CF01 001 BF021 BN151 001 CL051 CL092 CL093 CM041 CN021 CN031 DA017 DA026 DE047 DE077 DE087 DE107 DE117 DE137 DE147 DE187 DE237 DG047 DG057 DJ007 DJ017 DJ027 DJ037 DJ047 DJ057 DK007 DL007 FA047 FA067 FD016 FD017 FD020 FD070 FD070 FD080 D130 FD160 FD170 GN00

Claims (9)

[Claims] (1) 55 to 97% by weight of a thermoplastic resin,
(B) 100 parts by weight of (A) a resin composition comprising 3 to 45% by weight of an impact resistance improver, (B) 3 to 60 parts by weight of graphite having an average particle size of 1 to 70 μm, (C) antistatic resin 3 ~ 3
A vehicle exterior part obtained by molding a thermoplastic resin composition comprising 0 parts by weight. 2. A vehicle obtained by molding the thermoplastic resin composition according to claim 1, wherein the content of the impact modifier (b) in the resin composition (A) is 10 to 45% by weight. Exterior parts. 3. The thermoplastic resin according to claim 1, wherein (a) the thermoplastic resin is crystalline and has a melting point of 200 ° C. or higher.
Or a vehicle exterior part obtained by molding the thermoplastic resin composition according to 2. 4. A vehicle exterior part obtained by molding the thermoplastic resin composition according to any one of claims 1 to 3, wherein (a) the thermoplastic resin comprises a polyamide resin and / or a polyester resin. 5. The thermoplastic resin composition according to claim 1, wherein (C) the antistatic resin is a copolymer having a polyamide unit and a polyoxyalkylene unit as main components. Vehicle exterior parts. (6) 100 parts by weight of the resin composition (A)
(D) 5 to 60 parts by weight of an inorganic filler.
5. A vehicle exterior component obtained by molding the thermoplastic resin composition according to any one of the above items 5. 7. A vehicle exterior part obtained by molding the thermoplastic resin composition according to claim 6, wherein the inorganic filler (D) is a non-fibrous inorganic filler. 8. The method according to claim 6, wherein (D) the inorganic filler is talc.
Or a vehicle exterior part obtained by molding the thermoplastic resin composition according to 7. 9. An inorganic filler having an average particle diameter of 0.5 to 7 μm.
A vehicle exterior part obtained by molding the thermoplastic resin composition according to claim 8, which is talc of m.