JP2003285772A - Automobile outside plate member for vertical portion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automobile outside plate member for a vertical portion with heat resistance against baking finish, excellent dimension stability, excellent surface appearance, and high shock resistance in a low temperature, while having efficient rigidity. <P>SOLUTION: This automobile outside plate member for a vertical portion is composed of a polyamide resin composition obtained by constantly dispersing a silicate layer of swelling laminar silicate in polyamide resin at a molecule level. Addition volume of the swelling laminar silicate is 3-7 weight part per 100 weight part of polyamide resin, a linear expansion coefficient is 6.0×10<SP>-5</SP>/K or less, and a face shock strength is 10 J or more under a temperature of -30°C. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile outer panel member for a vertical portion, and more particularly to a polyamide resin composition in which a silicate layer of a swellable layered silicate is uniformly dispersed at a molecular level. The present invention relates to an automobile outer panel member which is excellent in impact resistance and is excellent in rigidity, heat resistance, dimensional stability, paintability and surface appearance by alloying a thermoplastic elastic copolymer in a base.

[0002]

2. Description of the Related Art In the automobile industry, in order to improve fuel efficiency, a resin-made outer plate material has been used instead of a metal-made outer plate material to reduce the weight. For example, materials mainly composed of polyphenylene ether resin and polyamide resin have been put into practical use. These resin compositions have the advantage that they can be simultaneously coated and baked on a metal automobile body, but have a large linear expansion coefficient and poor dimensional stability. In particular,
In addition to the strength and rigidity, the vertical part of the outer panel of an automobile does not affect the opening and closing of the door due to the temperature of the environment in which it is used. It is necessary to make the gap between the plate and the plate as small as possible, and a linear expansion coefficient lower than that of other parts is required.

In order to solve this problem, attempts have been made to add a filler to the above resin composition, but the rigidity and the dimensional stability are improved, but the impact strength is insufficient. It was Automobiles are usually premised on use in cold regions, and impact strength is required especially at low temperatures, but none of them satisfy this requirement. Further, materials mainly composed of polycarbonate resin and ABS resin and materials mainly composed of polycarbonate resin and polybutylene terephthalate resin have a smaller linear expansion coefficient and better dimensional stability than materials mainly composed of polyphenylene ether resin and polyamide resin. However, since the rigidity is low and the heat resistance is poor, it is necessary to lower the baking temperature at the time of coating and there is a drawback that productivity is poor. When a filler is added in order to improve rigidity and heat resistance, there is a problem that impact strength is greatly reduced like the resin composition described above.

[0004]

Therefore, in order to solve the above problems, an object of the present invention is to provide a vertical portion having excellent impact resistance, rigidity, heat resistance to baking coating, dimensional stability and surface appearance. An object is to provide a vehicle outer plate member.

[0005]

As a result of intensive studies, the present inventors have found that a polyamide resin composition in which a specific amount of a swellable layered silicate is uniformly dispersed in a polyamide resin at a molecular level and a thermoplastic elastic copolymer It was discovered that a resin composition having an excellent balance of rigidity, heat resistance, dimensional stability, and impact resistance in a specific ratio of a polymer can be suitably used as an automobile outer panel member in a vertical portion, and the present invention has been completed. That is, the present invention comprises a polyamide resin composition obtained by uniformly dispersing a silicate layer of a swellable layered silicate in a polyamide resin at a molecular level and a thermoplastic elastic copolymer, and the addition amount of the swellable layered silicate. Is 3 to 7 parts by weight per 100 parts by weight of the polyamide resin, and the coefficient of linear expansion is 6.0 × 10 ⁻⁵ / K or less, −3.
The gist of the present invention is a vehicle exterior plate member for vertical parts, which has a surface impact strength of 10 J or more at 0 ° C.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The polyamide resin composition of the present invention is a polyamide resin in which a silicate layer of a layered silicate is dispersed at the molecular level. Here, the silicate layer is a basic unit constituting a layered silicate, and is obtained by cleaving the layered silicate. The term “dispersed at the molecular level” means a state in which each layer silicate maintains an interlayer distance of 20 Å or more when dispersed in the polyamide resin matrix. The inter-layer distance refers to the distance between the centers of gravity of the silicate layers, and the term “dispersed” means that the silicate layers are parallel to each other or that the average overlap is 5 or less. Alternatively, it means a state in which 50% or more of the particles are present in the polyamide resin matrix without forming lumps randomly or in a state where parallel and random are mixed. Specifically, wide-angle X-ray diffraction measurement was performed on the polyamide resin composition pellet, and the peak due to the thickness direction of the layered silicate disappeared, or a transmission electron microscope of an ultrathin section obtained from the pellet. It can be confirmed by observation.

In the present invention, the polyamide resin means a polymer formed from aminocarboxylic acid, lactam or diamine and dicarboxylic acid (including a salt consisting of a pair thereof) and having an amide bond in the main chain. . Specifically, polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodeca Mido (nylon 612), polyundecamethylene adipamide (nylon 116), polyundecane amide (nylon 11), polydodecanamide (nylon 12), polytrimethylhexamethylene terephthalamide (nylon TMHT), polyhexamethylene isophthalamide (Nylon 6I), polyhexamethylene terephthal / isophthalamide (nylon 6T / 6I), polybis (4-aminocyclohexyl) methandodecamide (nylon PACM12), polybis (3-methyl-4)
-Aminocyclohexyl) methandodecamide (nylon dimethyl PACM12), polymethaxylylene adipamide (nylon MXD6), polynonamethylene terephthalamide (nylon 9T), polyundecamethylene terephthalamide (nylon 11T), polyundecamethylene hexa Hydroterephthalamide [nylon 11T (H)]
Or a copolymerized polyamide or a mixed polyamide thereof, preferably nylon 6 or nylon 66, or a copolymerized polyamide thereof, more preferably nylon 6
Alternatively, it is a copolyamide thereof.

The relative viscosity of the thermoplastic resin is not particularly limited. For example, when a polyamide resin is used, 96 wt% concentrated sulfuric acid is used as a solvent, the temperature is 25 ° C., and the concentration is 1 g / dl.
The value obtained under the conditions of is preferably in the range of 1.5 to 5.0, and particularly preferably in the range of 2.0 to 3.5. If the relative viscosity is less than 1.5, the mechanical strength is lowered and it cannot be applied as an automobile outer plate member. on the other hand,
If the relative viscosity exceeds 5.0, the moldability is remarkably reduced.

The swellable layered silicate in the present invention has a structure composed of a negatively charged layer containing silicate as a main component and a positive charge (ion) interposed between the layers. Preferred examples of such swellable layered silicates include smectites (eg, montmorillonite, beidellite, saponite, hectorite, sauconite), vermiculites (eg, vermiculite), mica (eg, fluoromica, muscovite, paragonite, There are phlogopite, phlogopite, biotite, lepidrite), brittle mica group (for example, margarite, clintnite, anandite), chlorite group (for example, donbasite, sudoite, cukeite, clinochlore, chamosite, nimmite). Alternatively, montmorillonite is more preferable. Among the fluoromica, swellable fluoromica is particularly preferable in terms of whiteness.

These layered silicates may be naturally occurring or artificially synthesized or modified. Further, they may be those treated with an organic substance such as an onium salt, but the swellable fluoromica described below has excellent dispersibility when added at the time of polymerization in the presence of a polyamide monomer, so that the onium salt, etc. It can be satisfactorily used without treatment of the organic substance.

Among the above layered silicates, the swellable fluoromica is represented by the following formula. Naα (Mg _x Liβ) Si ₄ O _y F _z (wherein 0 ≦ α ≦ 1, 0 ≦ β ≦ 0.5, 2.5 ≦ x ≦ 3
10 ≦ y ≦ 11, 1.0 ≦ z ≦ 2.0) Note that this equation shows an ideal composition ratio,
It does not have to be an exact match.

As a method for producing such a swellable fluoromica, for example, silicon oxide, magnesium oxide, and various fluorides are mixed, and the mixture is heated in an electric furnace or a gas furnace at a temperature range of 1400 to 1500 ° C. There is a so-called melting method in which fluorine mica is crystallized in a reaction vessel by completely melting it and cooling it. Further, there is a method in which talc is used as a starting material and an alkali metal ion is intercalated into the starting material to obtain a swellable fluoromica (JP-A-2-149415). In this method, swelling fluoromica can be obtained by mixing talc with alkali silicofluoride or alkali fluoride and heat-treating in a magnetic crucible at about 700 to 1200 ° C for a short time.

The swellable fluoromica can be controlled in particle size by means such as pulverization or classification, or can be removed of coarse particles. The preferred average particle size range is 0.5
˜20 μm, particularly preferably 1 to 10 μm. In addition, purification by removing non-swelling trace components can also be performed by hydration treatment. Among the above layered silicates, montmorillonite is represented by the following formula, and can be obtained by purifying naturally occurring ones. Na _x Si ₄ (Al _2-x Mg _x ) O ₁₀ (OH) ₂ · nH ₂ O (where x is 0.25 to 0.60 and n is an integer of 0 or more.) In addition, this formula or the following formula The groups represent ideal proportions and do not have to be exact matches. In particular, ion-exchangeable cations other than sodium may be present as impurities, as will be described later, and in this case also, they can be used in the present invention. Further, in montmorillonite, the same type ion-substituted compounds of magnesian montmorillonite, iron montmorillonite, and iron magnesian montmorillonite represented by the following formula group also exist, and these may be used. Na _x Si ₄ (Al _1.67-x Mg _{0.5 + x} ) O ₁₀ (OH) ₂ · n
H ₂ O Na _x Si ₄ (Fe (III) _2-x Mg _x ) O ₁₀ (OH) ₂ · nH
₂ O Na _x Si ₄ (Fe (III) _1.67-x Mg _{0.5 + x} ) O ₁₀ (OH)
₂ · nH ₂ O (in the formula, x is 0.25 to 0.60, and n is an integer of 0 or more.) Normally, montmorillonite may have ion-exchangeable cations such as calcium other than sodium between its layers. Ion exchange cations other than sodium existing between layers may be replaced with sodium by ion exchange treatment or the like. Further, purification with removal of non-swelling components can also be performed by hydration treatment.

The proportion of the layered silicate to be blended with the polyamide resin needs to be 3 to 7 parts by weight, preferably 4 to 6 parts by weight, per 100 parts by weight of the polyamide resin. If the blending amount is less than 3 parts by weight, the effect of improving rigidity is difficult to be exhibited, and at the same time, the heat resistance is insufficient, and deformation occurs when baking is performed during coating. Further, in terms of dimensional stability, the coefficient of linear expansion and the warp become large, and it cannot be applied as an automobile outer plate member, particularly as a vertical member. On the other hand, when the blending amount exceeds 7 parts by weight, the rigidity and dimensional stability are excellent, but the toughness and moldability are deteriorated. In order to improve the toughness, a large amount of the thermoplastic elastic copolymer must be blended, and as a result, the dimensional stability required as a vehicle outer panel member is impaired.

To obtain the polyamide resin composition of the present invention, a monomer such as aminocaproic acid, lactam or diamine, which forms the polyamide resin, and a dicarboxylic acid may be polymerized in the presence of a predetermined amount of the layered silicate.
It can also be obtained by melt-kneading an organically treated layered silicate obtained by previously inserting a predetermined amount of an organic compound between layers and the matrix resin.

The thermoplastic elastic copolymer in the present invention is a resin exhibiting rubber elasticity at room temperature, and known materials such as impact resistance improving materials for polyamide resins can be used and are not particularly limited. For example, polyolefin polymer, EP
Examples thereof include DM, MBS, SEBS, and polyamide elastomer. However, the thermoplastic elastomer is not limited thereto, and for example, a thermoplastic elastic copolymer having a functional group such as a carboxylic acid group, an epoxy group or a derivative thereof introduced therein can be used. Among them, it is preferable to use a polyolefin-based copolymer, and examples thereof include "Toughmer" manufactured by Mitsui Chemicals, Inc.

The weight ratio of the polyamide resin composition and the thermoplastic elastic copolymer may be appropriately determined from the viewpoint of balance with various physical properties such as rigidity, impact resistance and coefficient of linear expansion, and is not particularly limited, but 95 / The polymerization ratio is preferably from 5 to 80/20, and more preferably from 92/8 to 84/16. If the thermoplastic elastic body is less than 5% by weight, sufficient impact resistance cannot be obtained. On the other hand, if it exceeds 20% by weight, rigidity and dimensional stability are deteriorated, and further flow marks are likely to appear on the surface, which makes it difficult to obtain a beautiful molded product.

Further, various known additives may be added to the resin composition constituting the automobile outer panel structure of the present invention, as long as the characteristics thereof are not significantly impaired. Filler, mold release agent, flame retardant, fluidity improver, heat resistant material, antioxidant, weatherproofing agent, antistatic agent, pigment,
Examples include dyes.

The method for producing the resin composition constituting the present invention is not particularly limited, and known methods can be used.
Melt kneading is generally industrially advantageous. For melt-kneading, a kneading device such as a single-screw or twin-screw extruder, various kneaders, Banbury mixers, and Brabender can be used. In particular, a twin-screw extruder which is advantageous in kneading ability and economy is preferable.

The coefficient of linear expansion of the outer skin member for a vertical portion of the present invention must be 6.0 × 10 ^-5 / K or less.
It is preferably 5.5 × 10 ⁻⁵ / K or less. If this value exceeds 6.0 × 10 ^-5 / K, the temperature of the operating environment will affect the opening and closing of doors, and the gap between adjacent outer panels will need to be designed large, so the exterior appearance of the body It cannot be used for this purpose because it causes problems.

The surface impact strength at -30 ° C must be 10 J or more. When this value is less than 10 J, it is not practical because even a slight impact may cause cracks when placed in a cold environment.

The vehicle exterior plate member for a vertical portion of the present invention can be applied to the upper portion, front and rear sides, and both side portions of an automobile,
For example, it can be used for vertical parts such as side doors, front fenders, rear fenders (or quarters), lift gates (hatchbacks), front hoods, trunk lids and roofs.

Further, the automobile outer plate material for vertical portions of the present invention can be used not only in a general metal or metal-resin integral molding inner frame, but also in combination with a resin inner panel. The inner panel made of resin is not particularly limited, but reinforced polypropylene resin,
Examples include reinforced materials mainly composed of polycarbonate resin and polybutylene terephthalate resin, reinforced materials mainly composed of polycarbonate resin and polyethylene terephthalate resin, and the like. It is possible to contribute to further weight reduction by using the outer panel material for a vertical portion of the present invention in combination with the inner panel made of such a resin.

[0024]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples. The raw materials used in the examples and comparative examples and the methods for measuring the respective physical properties are as follows: 1. Raw material (a) Swellable layered silicate: With respect to talc pulverized by a fluorine mica ball mill so that the average particle size becomes 4 μm, sodium silicofluoride having the same average particle size of 4 μm becomes 20% by weight of the total amount. After mixing, this was put in a porcelain crucible and heat-treated at 800 ° C. for 1 hour in an electric furnace to synthesize fluoromica. Wide-angle X-ray diffraction measurement (RAD, RAD) of the purified fluoromica powder
As a result of using a -rB type X-ray diffractometer, the peak corresponding to the thickness 9.2Å of the raw material talc in the c-axis direction disappeared, and peaks corresponding to 12 to 16Å indicating the formation of fluoromica were observed. (B) Swellable layered silicate: montmorillonite A high-purity montmorillonite “Kunipia-F” manufactured by Kunimine Industries Co., Ltd., which was produced by subjecting natural montmorillonite produced in Yamagata prefecture to a hydrangea treatment, was used.

(C) Polyamide resin composition (PA-1) 1 kg of water and 3 to 10 kg of ε-caprolactam
00g of fluoromica (a) was added, and this was added to an internal volume of 3
It was placed in a 0 liter autoclave, heated to 260 ° C., and increased until the internal pressure became 1.5 MPa. After that, gradually releasing water vapor, pressure 1.5 MPa, temperature
After the polymerization was carried out for 2 hours while maintaining the temperature at 260 ° C., the pressure was released to normal pressure over 1 hour, and the polymerization was further carried out for 40 minutes. When the polymerization was completed, the above reaction product was discharged in a strand form, cooled, solidified, and cut to obtain pellets composed of a polyamide resin composition. Then, the pellets at 95 ° C
After scouring with hot water for 8 hours, it was vacuum dried. The obtained polyamide resin contains 3.2% by weight of a silicate layer,
The relative viscosity was 2.5. Further, when a wide-angle X-ray diffraction measurement was performed on the pellets of this polyamide resin composition, the peak in the thickness direction of fluoromica completely disappeared, and fluoromica was dispersed in the polyamide resin at the molecular level. I understood.

(D) Polyamide resin composition (PA-2) The above (c) except that 500 g of fluoromica (a) was used.
Pellets of a reinforced polyamide resin were obtained in the same manner as in. The obtained polyamide resin contained a silicate layer in an amount of 5.4% by weight and had a relative viscosity of 2.5. Moreover, when a wide-angle X-ray diffraction measurement was performed on the pellets of this polyamide resin composition, the peak in the thickness direction of fluoromica completely disappeared, and fluoromica was dispersed in the polyamide resin at the molecular level. I understood.

(E) Polyamide resin composition (PA-3) 400 g of fluoromica (a) was previously mixed with 100 g of ε-caprolactam, 10 kg of water and 85% by weight phosphoric acid aqueous solution.
16.1 g was added to the solution obtained by mixing, and the mixture was kept at 80 ° C. and stirred for 60 minutes using a homogenizer, and a mixed solution containing organically treated fluoromica (hereinafter referred to as “organized mica”). Got The organized mica was recovered by repeated filtration / washing with a Buchner funnel, then dried and ground. 400 g of this organic mica was added to nylon 6
After mixing with resin (Unitika's A1030BRL) pellets, using a twin-screw extruder (Ikegai Iron Works' PCM-30 type), melt kneading at a cylinder temperature of 250 ° C., then discharging into a strand, cooling and solidifying Then, the pellets were cut to obtain a reinforced polyamide resin pellet. Next, the pellets were scoured with hot water at 95 ° C. for 8 hours and then vacuum dried.
The obtained polyamide resin contained 6.5% by weight of a silicate layer and had a relative viscosity of 2.5. Moreover, when a wide-angle X-ray diffraction measurement was carried out on the pellets of this polyamide resin, the peak in the thickness direction of fluoromica completely disappeared, and it was found that fluoromica was dispersed in the polyamide resin at the molecular level. It was

(F) Polyamide resin composition (PA-4) Montmorillonite (b) instead of fluoromica (a)
Pellets of the polyamide resin composition were obtained in the same manner as in (c) except that the above was used. The obtained reinforced polyamide resin contains 4.3% by weight of a silicate layer and has a relative viscosity of 2.5.
Met. Further, when wide-angle X-ray diffraction measurement was performed on the pellets of this polyamide resin composition, the peak in the thickness direction of montmorillonite completely disappeared, and it was found that montmorillonite was dispersed in the polyamide resin at the molecular level. It was

(G) Polyamide resin composition (PA-5) The above (c) except that 150 g of fluoromica (a) was used.
Pellets of a reinforced polyamide resin were obtained in the same manner as in. The obtained polyamide resin contained 1.6% by weight of a silicate layer and had a relative viscosity of 2.5. Moreover, when a wide-angle X-ray diffraction measurement was performed on the pellets of this polyamide resin composition, the peak in the thickness direction of fluoromica completely disappeared, and fluoromica was dispersed in the polyamide resin at the molecular level. I understood.

(H) Polyamide resin composition (PA-6) 400 g of fluoromica (a) was previously mixed with 100 g of ε-caprolactam, 10 kg of water and 85% by weight phosphoric acid aqueous solution.
16.1 g was added to the solution obtained by mixing, and the mixture was kept at 80 ° C. and stirred for 60 minutes using a homogenizer, and a mixed solution containing organically treated fluoromica (hereinafter referred to as “organized mica”). Got The organized mica was recovered by repeated filtration / washing with a Buchner funnel, then dried and ground. 400 g of this organic mica was added to nylon 6
After mixing with resin (Unitika Co., A1030BRL) pellets, using a twin-screw extruder (Ikegai Tekko Co., Ltd., PCM-30 type), melt and knead at a cylinder temperature of 250 ° C., then paying out in a strand form, cooling and solidifying Then, the pellets were cut to obtain a reinforced polyamide resin pellet. Next, the pellets were scoured with hot water at 95 ° C. for 8 hours and then vacuum dried. The obtained polyamide resin contained 9.0% by weight of a silicate layer and had a relative viscosity of 2.5. In addition, when wide-angle X-ray diffraction measurement was performed on the pellets of this polyamide resin, the peak in the thickness direction of fluoromica completely disappeared, and it was found that fluoromica was dispersed in the polyamide resin at the molecular level. It was

(I) Non-reinforced polyamide resin (PA-
7): Unitika, A1030BRL (j) ABS resin (ABS): Asahi Kasei, Styrac 220 (k) Thermoplastic elastic copolymer: Maleic anhydride modified polyolefin copolymer, Mitsui Chemicals, Tuffmer MH50.
20 (l) Modified polyphenylene ether (modified PPE): poly
25 g of maleic anhydride was mixed with 5 kg of (2,6-dimethyl-1,4-phenylene) ether powder in a super mixer for 3 minutes, and melt-kneaded at 290 ° C. using a twin-screw extruder to obtain modified PPE. Got (M) Needle-shaped titanium oxide: FTL-200S manufactured by Ishihara Sangyo Co., Ltd.
(Average diameter 0.12 μm, fiber length 4 to 12 μm)

2. Measurement method (1) Flexural modulus: Measured according to the method described in ASTM-D790. (2) Deflection temperature under load: Measured with a load of 0.45 MPa according to the method described in ASTM-D648. (3) Surface impact strength: The surface impact strength was measured by dropping a weight from a predetermined height on a disk molded piece having a thickness of 1.6 mm and a diameter of 100 mm using a DuPont type falling weight impact tester. N = 5 under the condition of each height and weight combination, temperature-
It was measured at 30 ° C. The surface impact strength G is energy calculated by the following formula. _{G (J) = G 0 +} (G 1 -G 2) / 2 G0 :( maximum height molded piece does not destroy) × (gravitational acceleration) × (minimum height falling weight load) G1 :( molded piece is broken X) (gravitational acceleration)
X (Falling weight load) (4) Coefficient of linear expansion: Measured according to ASTM-D696. The sample was heated to 25 to 150 ° C in a heating furnace, and the coefficient of linear expansion was determined from the change in sample length between 30 and 140 ° C. (5) Warpage: A disk molded piece having a thickness of 1.6 mm and a diameter of 100 mm was placed on a horizontal plate and the maximum height and the minimum height were measured with a gauge, and the difference was defined as the amount of warpage. If there is no warp, the value will be 0 mm. (6) Thermal deformation: L: 127 mm, W: 127 mm, T:
A 3 mm plate was heat-treated at 180 ° C. for 30 minutes in an air oven, and the deformation was observed. Those that did not deform were marked with ◯, and those that deformed were marked with x. (7) Appearance: A test piece having a size of 50 mm × 90 mm and a thickness of 2 mm was prepared, and the gloss value at an incident angle of 60 degrees was measured with a gloss meter.

Example 1 A polyamide resin composition (PA-1) and a thermoplastic elastic copolymer (PO) were mixed at a weight ratio of 95/5 using a tumbler, and the mixture was mixed at 250 ° C. using a twin-screw extruder. Was melt-kneaded in, then discharged in a strand form, cooled, solidified, and then cut into pellets. The obtained pellets were dried with a hot air dryer at 120 ° C. for 3 hours, and then an injection molding machine (manufactured by Toshiba Machine,
(IS-80G), a test piece was prepared under the conditions of a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C., and each performance was evaluated. The results are shown in Table 1.

[0034]

[Table 1]

Example 2 Instead of the polyamide resin composition (PA-1), PA-2 was used.
Was used, and melt kneading and injection molding were carried out in the same manner as in Example 1 except that the ratio with the thermoplastic elastic copolymer was set to 90/10.

Example 3 Instead of the polyamide resin composition (PA-1), PA-3 was used.
Was used, and melt kneading and injection molding were performed in the same manner as in Example 1 except that the ratio with the thermoplastic elastic copolymer was set to 94/16.

Example 4 Instead of the polyamide resin composition (PA-1), PA-4 was used.
Was used, and melt kneading and injection molding were carried out in the same manner as in Example 1 except that the ratio with the thermoplastic elastic copolymer was set to 88/12, and test pieces were prepared.

Comparative Example 1 PA-5 was used instead of the polyamide resin composition (PA-1).
Was used, and melt kneading and injection molding were performed in the same manner as in Example 1 except that the ratio with the thermoplastic elastic copolymer was set to 98/2, and test pieces were prepared and subjected to the tests.

Comparative Example 2 PA-6 was used instead of the polyamide resin composition (PA-1).
Was used, and melt kneading and injection molding were carried out in the same manner as in Example 1 except that the ratio with the thermoplastic elastic copolymer was set to 70/30, and test pieces were prepared.

Comparative Example 3 PA-5 was used instead of the polyamide resin composition (PA-1).
Melt kneading and injection molding were carried out in the same manner as in Example 1 except that the test pieces were used to prepare test pieces, which were then subjected to the tests.

Comparative Example 4 Using ABS resin, an injection molding machine (manufactured by Toshiba Machine Co., IS-8
0G), cylinder temperature 200 ℃, mold temperature 60 ℃
A test piece was prepared under the conditions described above and each performance was evaluated. The results are shown in Table 1.

Comparative Example 5 Modified PPE, PA-5, and acicular titanium oxide were mixed in a ratio of 40/50 /
The mixture was mixed in a weight ratio of 10 using a tumbler, melt-kneaded using a twin-screw extruder at 280 ° C., then discharged in a strand form, cooled and solidified, and then cut and pelletized. The obtained pellets are dried with a hot air dryer at 120 ° C for 6 hours, and a test piece is prepared with an injection molding machine (TOSHIBA MACHINE, IS-80G) under the conditions of a cylinder temperature of 280 ° C and a mold temperature of 80 ° C. , Each performance was evaluated. The results are shown in Table 1.

As is clear from Table 1, in any of the comparative examples, the characteristics are deteriorated, whereas in this example, all the characteristics are well balanced,
It can be seen that it is suitable as a vehicle outer panel member for vertical parts.

[0044]

INDUSTRIAL APPLICABILITY The material of the present invention has excellent heat resistance to baking coating, dimensional stability, surface appearance, and high impact resistance at low temperatures, yet has sufficient rigidity, especially in vertical parts. It is suitable as a vehicle outer panel member.

Claims (3)

[Claims] 1. A polyamide resin composition comprising a polyamide resin in which a silicate layer of a swellable layered silicate is uniformly dispersed at a molecular level and a thermoplastic elastic copolymer, and the addition amount of the swellable layered silicate is 3 per 100 parts by weight of polyamide resin
-7 parts by weight, a linear expansion coefficient of 6.0 x 10 ^-5 / K or less, and a surface impact strength at -30 ° C of 10 J or more. 2. The automobile exterior panel member for a vertical portion according to claim 1, wherein the weight ratio of the polyamide resin composition and the thermoplastic elastic copolymer is 95/5 to 80/20. 3. A side door, a front fender, a rear fender, a lift gate, a front hood, a trunk lid, and a roof.
Or the vehicle exterior plate member for vertical parts according to 2.