JP2000211403A - Automotive interior parts with airbag doors - Google Patents

Abstract

(57) [Summary] (Modifications) [Problem] To provide an automobile interior part in which an airbag door excellent in heat aging performance and adaptable to environmental conditions from low temperature to high temperature is integrated. SOLUTION: It comprises A, B and C components, and A component and B component.
When the total of the components is 100 parts by weight, component A is 95 to 65 parts by weight of a polycarbonate resin having a viscosity average molecular weight of 19000 or more, component B is an aromatic alkenyl compound,
5 to 35 parts by weight of a polymer obtained from at least one monomer selected from methacrylates, acrylates and vinyl cyanide compounds, 20 to 40% by weight of a polyorganosiloxane C component and an acrylate rubber Graft copolymer 1 obtained by graft-polymerizing a type of monomer selected from aromatic alkenyl compounds, methacrylates, acrylates and vinyl cyanide compounds onto a composite rubber consisting of 80 to 60% by weight. 20
It is formed by molding a resin composition containing parts by weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile interior part having an airbag door, and more particularly, to an airbag door excellent in heat aging performance adaptable to a wide range of environmental conditions from a low temperature to a high temperature. The present invention relates to an automobile interior component having an airbag door, such as an instrument panel, a door trim, and a pillar garnish.

[0002]

2. Description of the Related Art In recent years, airbags have been standardly installed in automobiles for the purpose of improving safety performance against human bodies in the event of an accident. It is important that the airbag can be deployed in a wide range of environmental conditions from low to high temperatures.
At present, automotive interior parts such as instrument panels use glass fiber reinforced AS resin or polypropylene resin as the main body material, and the airbag doors that are deployed use thermoplastic olefin elastomers. A material having a low temperature dependency and a high impact resistance is used. However, such a configuration requires a lot of man-hours for attaching and a mold cost, and thus has a problem that it is unavoidable to be expensive.

On the other hand, in recent years, polycarbonate resin and AB
Automotive interior parts such as instrument panels in which an airbag door and a main body are integrally formed using a composite material made of S resin have been developed and are commercially available. However, this has a problem that deterioration due to heat or the like is likely to progress after aging.

[0004]

SUMMARY OF THE INVENTION Under such circumstances, the present invention is to provide an automobile interior part having an excellent heat aging performance which can be adapted to a wide range of environmental conditions from a low temperature to a high temperature, and particularly to an airbag door. It is an object of the present invention to provide an automotive interior part, such as an instrument panel, a door trim, or a pillar garnish, which is formed by molding.

[0005]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to develop interior parts for automobiles having the above-mentioned preferable properties, especially interior parts for automobiles integrated with an airbag door. It has been found that the object can be achieved by using, as a molding material, a resin composition in which a specific polymer and a graft copolymer are combined with a polycarbonate resin. The present invention has been completed based on such findings. That is, the present invention relates to the component (A),
When the total of the component (A) and the component (B) is 100 parts by weight, the component (A) has a viscosity average molecular weight of 19000 or more and a polycarbonate resin of 95 to 65 parts by weight, comprising the components (B) and (C). Part, (B) 5 to 35 parts by weight of a polymer obtained from at least one monomer selected from aromatic alkenyl compounds, methacrylic esters, acrylic esters and vinyl cyanide compounds,
And (C) a composite rubber comprising 20 to 40% by weight of a polyorganosiloxane and 80 to 60% by weight of an acrylate-based rubber, wherein an aromatic alkenyl compound, a methacrylic acid ester, an acrylic acid ester and a vinyl cyanide compound are used. Interior parts for automobiles, in particular, airbag doors integrated with an airbag door obtained by molding a resin composition containing 1 to 20 parts by weight of a graft copolymer obtained by graft polymerization of a selected monomer. Is provided as an interior part for an automobile.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the automotive interior part of the present invention, the polycarbonate resin as the component (A) in the resin composition used as the molding material is not particularly limited, and various resins can be used. This polycarbonate resin can be produced by a commonly used method, for example, by reacting a dihydric phenol with a polycarbonate precursor such as phosgene or a carbonate compound. Specifically, in a solvent such as methylene chloride, in the presence of a known acid acceptor or molecular weight regulator, and further, if necessary, a branching agent is added to react the dihydric phenol with a carbonate precursor such as phosgene. Or a transesterification reaction between a dihydric phenol and a carbonate precursor such as diphenyl carbonate.

There are various dihydric phenols, and in particular, 2,2-bis (4-hydroxyphenyl)
Propane (commonly known as bisphenol A) is preferred. Examples of the bisphenol other than bisphenol A include bis (4-hydroxyphenyl) methane; 1,1-
Bis (4-hydroxyphenyl) ethane; 2,2-bis (4-hydroxyphenyl) butane; 2,2-bis (4
-Hydroxyphenyl) octane; 2,2-bis (4-
2,2-bis (4-hydroxy-1-methylphenyl) propane; bis (4-hydroxyphenyl) naphthylmethane; 1,1
-Bis (4-hydroxy-t-butylphenyl) propane; 2,2-bis (4-hydroxy-3-bromophenyl) propane; 2,2-bis (4-hydroxy-3,5
-Tetramethylphenyl) propane; 2,2-bis (4
-Hydroxy-3-chlorophenyl) propane; 2,2
-Bis (4-hydroxy-3,5-tetrachlorophenyl) propane; 2,2-bis (4-hydroxy-3,5
Bis (hydroxyaryl) alkanes such as -tetrabromophenyl) propane; 1,1-bis (4-hydroxyphenyl) cyclopentane; 1,1-bis (4-hydroxyphenyl) cyclohexane; 1,1-bis (4 −
Bis (hydroxyaryl) cycloalkanes such as (hydroxyphenyl) -3,5,5-trimethylcyclohexane, 4,4′-dihydroxyphenyl ether;
Dihydroxyaryl ethers such as 4'-dihydroxy-3,3'-dimethylphenyl ether; 4,4'-
Dihydroxyphenyl sulfide; dihydroxydiaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethylphenyl sulfide; 4,4'-dihydroxyphenyl sulphoxide; 4,4'-dihydroxy-
Dihydroxydiarylsulfoxides such as 3,3'-dimethylphenylsulfoxide, 4,4'-dihydroxydiphenylsulfone;4,4'-dihydroxy-3,
Dihydroxydiarylsulfones such as 3′-dimethyldiphenylsulfone; and dihydroxydiphenyls such as 4,4′-dihydroxydiphenyl. These dihydric phenols may be used alone or as a mixture of two or more.

Examples of the carbonate compound include diaryl carbonates such as diphenyl carbonate, and dialkyl carbonates such as dimethyl carbonate and diethyl carbonate. And as a molecular weight modifier, what is normally used for polymerization of polycarbonate may be used, and various types can be used. Specifically, as the monohydric phenol, for example, phenol, o-
n-butylphenol, mn-butylphenol, p
-N-butylphenol, o-isobutylphenol,
m-isobutylphenol, p-isobutylphenol, ot-butylphenol, mt-butylphenol, pt-butylphenol, on-pentylphenol, mn-pentylphenol, pn-pentylphenol, o -N-hexylphenol, mn
-Hexylphenol, pn-hexylphenol,
pt-octylphenol, o-cyclohexylphenol, m-cyclohexylphenol, p-cyclohexylphenol, o-phenylphenol, m-phenylphenol, p-phenylphenol, on-nonylphenol, mn-nonylphenol, p-octylphenol n-
Nonylphenol, o-cumylphenol, m-cumylphenol, p-cumylphenol, o-naphthylphenol, m-naphthylphenol, p-naphthylphenol, 2,5-di-t-butylphenol; 3,5-dicumylphenol; 3,5-dicumylphenol; p-cresol, bromophenol, tribromophenol and the like. Among these monohydric phenols, pt-butylphenol, p-cumylphenol, p-phenylphenol and the like are preferably used.

Other branching agents include, for example, 1,
1,1-tris (4-hydroxyphenyl) ethane;
α, α ', α "-tris (4-hydroxyphenyl)-
1,3,5-triisopropylbenzene; 1- [α-methyl-α- (4′-hydroxyphenyl) ethyl] -4
-[Α ', α'-bis (4 "-hydroxyphenyl) ethyl] benzene; compounds having three or more functional groups such as phloroglysin, trimellitic acid, and isatin bis (o-cresol) can also be used. As the polycarbonate resin used in the above, a viscosity average molecular weight M
Those having v of 19000 or more are preferred, and preferably 1950
0 to 24000. Viscosity average molecular weight Mv of 1900
If it is smaller than 0, the heat aging resistance may be insufficient. The polycarbonate resin may be used alone or in combination of two or more.

In the resin composition, the polymer used as the component (B) is at least one monomer selected from aromatic alkenyl compounds, methacrylic esters, acrylic esters and vinyl cyanide compounds. Or a homopolymer or copolymer obtained from The polymer of the component (B) has a function of imparting fluidity to the resin composition. However, in order to improve the dispersibility of the rubber component as the component (C) described below, the polymer (C) is used. It is desirable to use a polymer obtained from the same graft copolymerization component as the component (A) or a polymer having good compatibility with the component (C). Particularly, a copolymer of an aromatic alkenyl compound and a vinyl cyanide compound is preferable. Polymers are preferred. Examples of the aromatic alkenyl compound include styrene, α-methylstyrene, o-, m- or p-methylstyrene, ethylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene,
Examples thereof include pt-butylstyrene and vinylnaphthalene. Of these, styrene and α-methylstyrene are preferred. Examples of the methacrylate include methyl methacrylate, ethyl methacrylate,
Ethylhexyl methacrylate, glycidyl methacrylate and the like can be mentioned, and among these, methyl methacrylate is preferable. Examples of the acrylate include methyl acrylate, ethyl acrylate, and butyl acrylate. Of these, methyl acrylate and ethyl acrylate are preferred. Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile.

In the present invention, as the component (B), one kind of a homopolymer obtained by appropriately selecting and polymerizing one of the various monomers may be used, or two or more kinds may be appropriately selected,
One of the copolymers obtained by polymerization may be used, or two or more of the homopolymers and copolymers may be appropriately selected and used in combination. Examples of the homopolymer include polystyrene, poly α-methylstyrene, polymethyl methacrylate, polymethyl acrylate, polyethyl acrylate, and polyacrylonitrile. Examples of the copolymer include a styrene-acrylonitrile copolymer and acrylonitrile- Examples include a methyl methacrylate copolymer, an acrylonitrile-styrene-acrylate copolymer, and a styrene-α-methylstyrene copolymer. Among these, a styrene-acrylonitrile copolymer is particularly preferred.

On the other hand, the rubbery component as the component (C) in the resin composition includes a composite rubber of a polyorganosiloxane and an acrylate rubber, an aromatic alkenyl compound, a methacrylate, an acrylate and a vinyl cyanide. A graft copolymer obtained by graft-polymerizing at least one monomer selected from compounds is used. The composite rubber composing the graft copolymer has a polyorganosiloxane content of 20 to 40% by weight, preferably 2 to 40% by weight.
It comprises 5 to 35% by weight, 80 to 60% by weight of acrylate rubber, preferably 75 to 65% by weight. The above-mentioned graft copolymer is used as the composite rubber 1
50 parts by weight of at least one of the above monomers in 50
A graft copolymer obtained by graft polymerization at a ratio of about 80 parts by weight is preferably used.

The component (C) is a rubber component having a core-shell structure obtained by graft-polymerizing a styrene-acryl chain or the like to the composite rubber, and its production method is disclosed in JP-A-64-79257. ing. Examples of the composite rubber in the graft copolymer include an alkyl (meth) acrylate and a polyorganosiloxane latex obtained by adding a crosslinking agent and a graft cross-linking agent (vinyl-containing siloxane) to dimethylsiloxane and polymerizing the same. After impregnating an alkyl (meth) acrylate component consisting of a polyfunctional alkyl (meth) acrylate,
A composite rubber composed of a polyorganosiloxane rubber obtained by polymerization by adding a radical polymerization initiator and an acrylate rubber is preferably exemplified. Examples of the aromatic alkenyl compound, methacrylic acid ester, acrylic acid ester, and vinyl cyanide compound to be graft-polymerized on the composite rubber include the same compounds as those exemplified in the description of the component (B). These monomers may be used alone or in combination of two or more.
In particular, it is preferable to use styrene and acrylonitrile in combination. It is advantageous to carry out the graft polymerization in one or more stages.

In the present invention, as the component (C), one kind of the graft copolymer may be used, or two or more kinds thereof may be used in combination. About the compounding ratio of each component in the resin composition used as the molding material of the interior parts for automobiles of the present invention, 95-65 parts by weight, preferably 90-75 parts by weight, of the component (A) and 5-35 of the component (B).
100 parts by weight, preferably 10 to 25 parts by weight
Component (C) may be selected in an amount of 1 to 20 parts by weight, preferably 5 to 15 parts by weight, based on parts by weight. (A)
When the amount of the component (A) is less than 65 parts by weight in the mixing ratio of the component and the component (B), it is difficult to obtain a desired heat aging resistance.
If it exceeds 95 parts by weight, the fluidity may decrease. On the other hand, if the amount of the component (C) is less than 1 part by weight, the desired elongation may not be obtained after the heat aging test, and if it exceeds 20 parts by weight, the fluidity tends to decrease.

[0015] In addition to the essential components, the resin composition
If desired, various known additives such as antioxidants such as phosphorus-based antioxidants, phenol-based antioxidants, and sulfur-based antioxidants, benzotriazole-based and benzophenone, as long as the object of the present invention is not impaired. UV absorber, hindered amine light stabilizer, aliphatic carboxylic acid ester, paraffin, silicone oil, polyethylene wax and other internal lubricants, as well as flame retardants, flame retardant assistants, antistatic agents, inorganic fillers Agent, organic filler, release agent,
A coloring agent and the like can be blended. The method for preparing the resin composition is not particularly limited, and a known method can be used. For example, the component (A), the component (B),
The component (C) and various additives optionally used are compounded using a ribbon tumbler, a Henschel mixer, a Banbury mixer, a drum tumbler, a single screw extruder, a twin screw extruder, a co-kneader, a multi-screw extruder, or the like. By kneading, a resin composition can be prepared. In addition, the heating temperature at the time of kneading is usually selected in the range of 240 to 300 ° C.

In the present invention, the resin composition thus obtained has a tensile elongation at 23 ° C. or −10 ° C. of 30% or more after a heat aging test at 110 ° C. for 2400 hours. The embrittlement temperature after the test is −30 ° C. or less,
Those having a melt flow rate (280 ° C., 5.0 kg load) of 30 g / 10 min or more are suitable as molding materials for interior parts for automobiles. The heat aging test is performed according to the following method. JI using resin composition
An SA type test piece was prepared and left in an oven at 110 ° C. for 2400 hours to perform a heat aging test.
According to STM D638, the tensile elongation (%) and the embrittlement temperature (° C.) at each of 23 ° C. and −10 ° C. are measured. The automotive interior part of the present invention is obtained by molding the above resin composition according to a known method, and particularly preferably is one integrally molded with an airbag door. FIG. 1 is a perspective view showing an instrument panel, which is an example of an automobile interior part of the present invention, integrally formed with an airbag door. The airbag is stored.

[0017]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The materials used are as follows. Polycarbonate resin: "Teflon FN2200A" / "FN1900A" manufactured by Idemitsu Petrochemical Co., Ltd. was blended to adjust the viscosity average molecular weight (Mv) to 20,500. AS resin: "290FF" manufactured by Technopolymer ABS resin: "AT-05" manufactured by Mitsui Chemicals, Inc. Composite rubber S1: "METABLEN SR" manufactured by Mitsubishi Rayon Co., Ltd.
K-200 ", polyorganosiloxane content 30% by weight Composite rubber S2:" METABLEN S- "manufactured by Mitsubishi Rayon Co., Ltd.
2001 ", polyorganosiloxane content 10% by weight

The test method used in the examples is as follows. (1) Method for measuring viscosity average molecular weight Mv The method for measuring viscosity average molecular weight Mv is to measure the viscosity of a methylene chloride solution at 20 ° C. with an Ubbelohde viscometer,
After obtaining the intrinsic viscosity [η] from this, it is calculated by the following equation. [Η] = 1.23 × 10 ⁻⁵ Mv ^0.83 (2) Measurement of tensile elongation In accordance with ASTM D638, the tensile elongation (%) at 23 ° C. and −10 ° C. in a temperature atmosphere is measured. (3) Measurement of embrittlement temperature According to JIS K7216, an Ambient temperature at which the number of brittle fractures becomes 5 or more for the first time using ten A-type test pieces is measured as an embrittlement temperature. It is impossible to measure below −65 ° C. due to the measuring instrument, and when the number of fractures of 10 test pieces measured at −65 ° C. is 5 or less, the embrittlement temperature is −
65 ° C. or less. (4) Measurement of melt flow rate The melt flow rate is measured at 280 ° C. under a load of 5.0 kg according to JIS K7210.

Example 1 The following component (a): 80 parts by weight, component (b): 20 parts by weight,
(C) Component 15 parts by weight, phosphorus-based antioxidant (Irgafos 168, manufactured by Ciba Specialty Chemicals Co., Ltd.)
1 part by weight and a phenolic antioxidant (Irganox 107 manufactured by Ciba Specialty Chemicals Co., Ltd.)
6) 0.1 parts by weight were uniformly mixed using a Henschel mixer, and then melt-kneaded at a resin temperature of about 250 ° C. to 300 ° C. in a single screw extruder (NVC 50B), and pelletized at 100 k.
g was obtained. (A) Polycarbonate having a viscosity average molecular weight of 20,000 (a blend of Teflon FN2200 and FN1900 at a mixing ratio of 1: 2, manufactured by Idemitsu Petrochemical Co., Ltd.) (hereinafter referred to as "PC1") (b) Styrene-acrylonitrile copolymer Combined (Techno Polymer Co., Ltd., 290FF) (hereinafter referred to as "AS resin") (c) Polyorganosiloxane content in composite rubber is 3
A graft copolymer (manufactured by Mitsubishi Rayon Co., Ltd.) which is 0% by weight, has an n-butyl acrylate rubber content of 70% by weight, and is 50 parts by weight of styrene-acrylonitrile (based on 100 parts by weight of the composite rubber). , Metablen S
RK-200) (hereinafter referred to as “S1”) Using the obtained pellets, first, a melt flow rate was measured, and then a tensile elongation test piece and an embrittlement temperature test piece were prepared. The specimen was left to stand for at least 24 hours in an atmosphere, and the condition was adjusted, and a tensile test and an embrittlement temperature test were performed. The initial tensile elongation (%) and the initial embrittlement temperature (° C) were respectively performed.
And Further, the test piece after the conditioning was heated to a temperature of 110 ° C.
Was left in an oven for 2400 hours to perform a heat aging test. After the lapse of time, remove the test piece from the oven,
After standing for at least 24 hours in an atmosphere of a temperature of 23 ° C. and a humidity of 50%, the condition was adjusted, a tensile test and an embrittlement temperature test were performed, and a tensile elongation (%) after the heat aging test and a brittleness after the heat aging test, respectively. Temperature (° C.). Table 1 shows the evaluation results.

Example 2 In Example 1, the amount of the component (a) was changed from 80 parts by weight to 90 parts by weight.
A resin composition was prepared and evaluated in the same manner except that the amount of the component (b) was changed from 20 parts by weight to 10 parts by weight, and the amount of the component (c) was changed from 15 parts by weight to 10 parts by weight. did. Table 1 shows the evaluation results.

Example 3 In Example 1, the amount of the component (a) was changed from 80 parts by weight to 85 parts by weight.
A resin composition was prepared and evaluated in the same manner except that the amount of the component (b) was changed from 20 parts by weight to 15 parts by weight, and the amount of the component (c) was changed from 15 parts by weight to 5 parts by weight. did. Table 1 shows the evaluation results.

COMPARATIVE EXAMPLE 1 In Example 1, the component (a) was replaced by a component having a viscosity average molecular weight of 185.
No. 00 polycarbonate (manufactured by Idemitsu Petrochemical Co., Ltd.
A resin composition was prepared and evaluated in the same manner except that Toughlon FN1700 and FN1900 were blended at a blending ratio of 1: 3 (hereinafter referred to as "PC2"). Table 1 shows the evaluation results.

Comparative Example 2 In Example 1, the amount of the component (a) was changed from 80 parts by weight to 60 parts by weight.
A resin composition was prepared and evaluated in the same manner except that the amount of the component (b) was changed from 20 parts by weight to 40 parts by weight, and the amount of the component (c) was changed from 15 parts by weight to 10 parts by weight. did. Table 1 shows the evaluation results.

Comparative Example 3 In Example 1, the amount of the component (a) was changed from 80 parts by weight to 10 parts.
A resin composition was prepared in the same manner except that the amount of the component (b) was changed from 20 parts by weight to 0 parts by weight and the amount of the component (c) was changed from 15 parts by weight to 10 parts by weight. evaluated. Table 1 shows the evaluation results.

Comparative Example 4 In Example 1, the content of the polyorganosiloxane in the composite rubber as the component (c) was 10% by weight and n
The butyl acrylate rubber content is 70% by weight,
50 parts by weight of styrene-acrylonitrile (composite rubber 10
(Based on 0 parts by weight) (METABLEN S2001 manufactured by Mitsubishi Rayon Co., Ltd.) (hereinafter referred to as “S2”).
), And the amount of the component (a) is changed from 80 parts by weight to 90 parts by weight.
A resin composition was prepared and evaluated in the same manner except that the amount of the component (b) was changed from 20 parts by weight to 10 parts by weight, and the amount of the component (c) was changed from 15 parts by weight to 5 parts by weight. did. Table 1 shows the evaluation results.

Comparative Example 5 In Example 1, the amount of the component (a) was changed from 80 parts by weight to 70 parts by weight.
Parts by weight of component (b) from 20 parts by weight to 0 parts by weight, and component (c) from S1 to ABS resin (Santac AT
−05, butadiene content: 12 to 13%), and a resin composition was prepared and evaluated in the same manner. Table 1 shows the evaluation results.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

The automotive interior parts of the present invention are excellent in heat aging performance adaptable to a wide range of environmental conditions from low to high temperatures, and satisfy the airbag deployment performance. In particular, the interior parts and the airbag door for automobiles What was integrated and molded,
In addition to having the above performance, it is advantageous in terms of cost.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of the present invention in which an instrument panel main body and an airbag door are integrally formed.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) C08L 25:00 51:08 51:00) (C08L 69/00 33:06 51:08 51:00) ( C08L 69/00 33:18 51:08 51:00) (72) Inventor Koichi Hara 1-1, Anesaki Beach, Ichihara City, Chiba Prefecture (72) Inventor Toshiaki Sugawara 1, Toyota-cho, Toyota City, Aichi Prefecture Toyota Automobile Stocks Inside the company (72) Inventor Hideaki Takahashi 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (4)

[Claims] 1. Component (A), component (B) and component (C), wherein component (A) has a viscosity average molecular weight of 100 parts by weight based on the total of component (A) and component (B). 1900
95 to 65 parts by weight of a polycarbonate resin which is 0 or more,
Component (B) is 5 to 35 parts by weight of a polymer obtained from at least one monomer selected from aromatic alkenyl compounds, methacrylic acid esters, acrylic acid esters and vinyl cyanide compounds; 20 to 40% by weight of polyorganosiloxane and acrylate rubber 80 to 6
1 to 20% by weight of a graft copolymer obtained by graft-polymerizing a type of monomer selected from aromatic alkenyl compounds, methacrylates, acrylates and vinyl cyanide compounds onto a composite rubber comprising 0% by weight. Interior parts for automobiles in which an airbag door formed by molding a resin composition containing a part is integrated. 2. The automotive interior part according to claim 1, wherein the component (B) is a styrene-acrylonitrile copolymer. 3. The automotive interior according to claim 1, wherein the resin composition has a tensile elongation at 23 ° C. or −10 ° C. of 30% or more after a heat aging test at 110 ° C. for 2400 hours. parts. 4. The vehicle interior part according to claim 1, wherein the vehicle interior part is an instrument panel.