JP2002283482A - Interior material of automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interior material of an automobile which can reduce the noise in the automobile so as to improve comfortableness of a driver and a passenger, while maintaining the characteristics as the interior material of the automobile, such as lightweight properties, heat insulating properties, moldability and heat resistance. SOLUTION: In respect to a non-air-permeable closed-cell foamed laminated sheet regarded heretofore as difficult to be given a sound-absorbing performance, the degree of freedom of the vibration of a non-foamed layer laminated on a foamed layer is enhanced by making the foamed layer highly foamable and the sound-absorbing performance is given by utilizing the effect of interference of the sound generated by the vibration of the non-foamed layer. Thus, both of the non-air-permeability and the sound-absorbing performance are given compatibly to the material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an automobile interior material. More specifically, the present invention relates to an automobile interior material capable of reducing in-vehicle noise in order to improve occupant comfort.

[0002]

2. Description of the Related Art Conventionally, as an interior material for automobiles, a material obtained by laminating a urethane foam on a base material mainly composed of a thermoplastic resin foam or a styrene-maleic anhydride copolymer foam layer is provided on the upper and lower surfaces. A sheet formed by laminating a non-foamed layer of a maleic acid copolymer into a desired shape is widely used. These automobile interior materials are characterized by being lightweight, having high heat insulating properties, and having excellent moldability.

[0003] However, the conventional automobile interior materials as described above have insufficient heat resistance when exposed to high temperatures for a long period of time, so that the front portion hangs down under its own weight (heat sag), and deformation occurs. May occur.

[0004] In order to solve these problems,
Automotive interior materials based on composite materials of inorganic glass fibers and plastics have been used. However, in this composite material, although the quality of heat resistance can be maintained, there is a problem that the weight cannot be reduced, and the use of glass fiber causes poor recyclability and high cost.

In order to solve such a problem, a non-foamed layer of a modified PPE-based resin is laminated on both sides of a foamed layer of a modified polyphenylene ether-based resin (hereinafter referred to as “modified PPE-based resin”) which is lightweight and has heat resistance. There has been proposed a foam laminated sheet for an automobile interior material using the foamed laminated sheet (Japanese Utility Model Laid-Open No. 4-1162). Also, Japanese Patent Application Laid-Open No. Hei 6-344
No. 483 discloses a foaming ratio of 5 to 20 times and a thickness of 2 to 6 m.
A foam laminated sheet for an automobile interior material has been proposed in which a modified PPE-based resin non-foamed layer is laminated on both sides of a modified PPE-based resin foamed layer having various properties such as m, an open cell ratio of 5 to 25%, and the like. Since the foam laminated sheet for automobile interior materials using these modified PPE resins has excellent heat resistance and is lightweight,
It is said that deformation under high temperature and sagging due to its own weight can be improved.

In recent years, automobiles have become more sophisticated and higher in performance, and quietness inside the car is required. However, in the case of automobile interior materials using the above-described modified PPE resin foam laminated sheet, the quietness inside the car is reduced. Sound absorption performance that is closely related is not provided, and in order to provide sound absorption performance, it is necessary to use expensive skin material with sound absorption performance, paste sound absorbing material such as urethane foam layer, etc. As a result, material costs and manufacturing costs were increased.

On the other hand, urethane foam (JP-A-63-1) has been conventionally used as an automobile interior material having sound absorbing performance.
No. 99182), urethane foam and fiber (Japanese Unexamined Patent Publication No.
No. 63703) and short fibers (JP-A-2-95838) are known. In automobile interior materials having these sound absorbing performances, when sound is applied to the base material, the air vibration is transmitted to the air in the pores inside the base material, and the viscous friction of the air is generated in the pores and the sound is vibrated. A part of the energy is converted into heat energy, and a sound absorbing performance is generated. In other words, the vibration is attenuated by the resistance to the movement of air,
This utilizes the effect of reducing the sound. In order to exhibit this effect, the substrate needs to have air permeability. However, when a base material having air permeability is used, when air flows from the inside of the vehicle to the outside of the vehicle,
The skin layer plays a role of a filter, and the upper part of the skin layer is stained like a hole, which has been a problem.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been proposed to provide a non-breathable closed-cell foam laminated sheet which has been considered difficult to impart sound absorbing performance. Found that by increasing the foaming of the foaming layer, the degree of freedom of vibration of the non-foaming layer laminated on the foaming layer can be increased, and sound absorption performance can be imparted by utilizing the sound interference effect due to the vibration of the non-foaming layer. The present invention has been completed.

That is, the present invention provides [1] a skin material (1)
And a foamed laminate (2), the foamed laminate (2) has a non-foamed layer made of a thermoplastic resin on both sides of a foamed layer (3) having a modified polyphenylene ether-based resin as a base resin. An automobile interior material having a structure in which the foam layers (4) and (5) are laminated, and wherein the expansion ratio of the foam layer (3) is more than 20 times and 100 times or less. [2] The automotive interior material according to [1], wherein the foaming ratio of the foamed layer (3) is 25 to 70 times. [3] The automotive interior material according to [1] or [2], wherein the thermoplastic resin as a base resin of the non-foamed layer (4) is a modified polyphenylene ether-based resin. [4] The content of the phenylene ether component in the modified polyphenylene ether-based resin as the base resin of the foamed layer (3) is 35% by weight to 75% by weight, and the content of the styrene-based component is 65% by weight to 25% by weight. The automobile interior material according to any one of [1] to [3], wherein the content is weight%.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an example of an automotive interior material and a foam laminate sheet for an automobile interior material according to the present invention.

FIG. 1 shows the structure of an automobile interior material according to one embodiment of the present invention. A thermoplastic resin is provided on both sides of a foamed layer (3) using a heat-resistant resin as a base resin. A non-foamed layer (vehicle inner non-foamed layer (4) and vehicle outer non-foamed layer (5)) made of resin is formed, and a hot melt adhesive layer (6) is formed on the upper surface of the car inner non-foamed layer (4). The skin material (1) is laminated via the.

Foamed layer using heat-resistant resin as base resin (3)
Is a layer serving as a base material of an automobile interior material, and since this layer (3) is made of a resin having good heat resistance and moldability, an automobile interior material as a secondary foam laminated molded article can be easily molded.
In addition, since this layer (3) is a foamed layer, it is lightweight and has excellent heat insulating properties, and because of its low density, only a small amount of resin is used, which is cost-competitive.

As the heat-resistant resin used as the base resin of the foamed layer (3) of the present invention, any resin known to those skilled in the art as having heat resistance can be used. For example, heat-resistant polystyrene resins such as styrene-acrylic acid copolymer, styrene-maleic anhydride copolymer, styrene-itaconic acid copolymer; polystyrene or a blend of heat-resistant polystyrene and polyphenylene ether (PPE); Modified polyphenylene ether-based resin (modified PPE-based resin) such as styrene-phenylene ether copolymer such as styrene graft polymer to PPE; polycarbonate resin; and polyester resin exemplified by polybutylene terephthalate and polyethylene terephthalate. . Two or more of these resins can be used. Among these, the use of a modified PPE-based resin as the base resin of the foamed sheet is preferable because it has excellent quality such as heat resistance and rigidity, and is easy to process and easy to manufacture.

Examples of the PPE resin used for the modified PPE resin include poly (2,6-dimethylphenylene-1,4-ether), poly (2-methyl-6-ethylphenylene-4-ether), Poly (2,6-diethylphenylene-1,4-ether), poly (2,6-diethylphenylene-1,4-ether), poly (2-methyl-6-n-propylphenylene-1,4-ether) ), Poly (2-methyl-6-n-butylphenylene-)
1,4-ether), poly (2-methyl-6-chlorophenylene-1,4-ether), poly (2-methyl-6
-Bromophenylene-1,4-ether), poly (2-
Ethyl-6-chlorophenylene-1,4-ether) and the like, and these are used alone or in combination of two or more.

Among the modified PPE resins, the PS resin forming a mixed resin with the PPE resin is styrene or a derivative thereof, for example, α-methylstyrene, 2,4-dimethylstyrene, monochlorostyrene, dichlorostyrene, p-methyl. It is a resin containing styrene, ethylstyrene and the like as main components. Therefore, the PS-based resin is not limited to a homopolymer composed of only styrene or a styrene derivative, and may be a copolymer produced by copolymerizing with another monomer.

Specific examples of the styrene monomer to be polymerized, preferably graft-polymerized to the PPE resin include, for example, styrene, α-methylstyrene, 2,4-
Examples include dimethylstyrene, monochlorostyrene, dichlorostyrene, p-methylstyrene, ethylstyrene and the like. These may be used alone or in combination of two or more. Of these, styrene is versatile,
It is preferable in terms of cost.

When a modified PPE resin is used as the base resin used in the foamed layer of the present invention, the phenylene ether component is preferably 35 to 75 parts by weight, and the styrene component is preferably 65 to 25 parts by weight, more preferably. Is preferably 35 to 60 parts by weight as a phenylene ether component, 65 to 40 parts by weight as a styrene component, particularly preferably 38 to 58 parts by weight as a phenylene ether component and 62 to 42 parts by weight as a styrene component. When the mixing ratio of the PPE-based resin is small, the heat resistance tends to be inferior. When the mixing ratio of the PPE-based resin is large, the viscosity during heating and flowing tends to increase, and foam molding tends to be difficult.

The modified PPE resin foam layer has a thickness of 3 to 2
It is preferably 0 mm, more preferably 4 to 10 mm. When the thickness of the foamed layer is less than 3 mm, the strength and the heat insulating property are inferior and may not be suitable as an automobile interior material. Meanwhile, 2
If it exceeds 0 mm, it may not be practically appropriate due to reasons such as securing space in the interior of the automobile and restrictions on the interior design.

The modified PPE resin foam layer has an expansion ratio of 20.
It is preferably more than 100 times or less, more preferably 25 to 70 times. Most preferably, it is 30 to 60 times. This is because the automobile interior material of the present invention utilizes a sound interference effect caused by vibration of a non-foamed layer laminated on the foamed layer, by reducing the spring multiplier by increasing the magnification of the foamed layer. Is less than 20 times, the effect of reducing the spring constant is not sufficient, and the sound absorption performance tends not to be improved. When the expansion ratio exceeds 100 times, the cell membrane density tends to be too low and the heat resistance tends to deteriorate.

The modified PPE foamed layer has a closed cell ratio of preferably 70% or more, more preferably 80% or more. 70% closed cell rate
If it is less than 3, the heat insulating property and rigidity tend to be poor.

The base resin of the foamed layer (3) used in the present invention may contain, if necessary, a cell regulator, an impact resistance improver, a lubricant, an antioxidant, an antistatic agent, a pigment and a stabilizer. And an odor reducing agent may be added.

Next, a non-foamed layer (4, 5) of a thermoplastic resin is formed on both sides of the foamed heat resistant resin layer (3) in the interior material of the automobile according to the present invention. Among these non-foamed layers (4, 5), the non-foamed layer (4) on the inside of the vehicle functions to suppress the heat shrinkage of the skin material (1) laminated on one surface and to form the foamed material on the other surface. The cells in which the layer (3) is elongated at the time of molding and flattened have a function of suppressing the heat shrinkage caused by changing the shape in the direction of eliminating the flattening rate at the time of heating. Further, the non-foamed layer (5) on the vehicle outside has a function of suppressing heat shrinkage of the foamed layer (3).

Here, the heat shrinkage of the foamed layer (3) is greatly affected by the cell shape, the change in cell internal pressure due to curing, the closed cell rate, the heating temperature, etc., and it is very difficult to control the shrinkage. . However, the deformation of the front part under high temperature is greatly affected by the heat shrinkage of the foamed layer (3). It is important to suppress in the layers (4, 5).

Next, the thermoplastic resin used for the non-foamed layers (4, 5) includes a heat-resistant PS resin, a modified PPE resin, a polypropylene resin, a polyethylene terephthalate (PET) resin, and a polyamide (nylon) resin. And the like. These may be used alone or in combination of two or more. When a modified PPE-based resin is used as the foamed layer (3), the modified PPE resin is used from the viewpoint of adhesiveness to the resin layer. Resins and heat-resistant PS resins are preferably used.

When the modified PPE resin is used as the non-foamed layer (4, 5), similar to the foamed layer (3),
Modified by polymerization or mixing with a monomer or a polymer mainly composed of a PPE-based resin and a styrene-based compound. For example, a mixed resin of a PPE-based resin and a PS-based resin, and styrene as a PPE-based resin. P obtained by polymerizing system monomers
Examples thereof include a PE-styrene copolymer, a mixture of the copolymer with a PS-based resin or a PPE-based resin, and a mixture of the copolymer with a PPE-based resin and a PS-based resin. Among these, a mixed resin of a PPE-based resin and a PS-based resin is preferred from the viewpoint of easy production.

Specific examples and preferable examples of the PPE resin, PS resin and styrene monomer are described.
Specific examples of monomers that can be polymerized with a series resin or styrene monomer,
The reason for using it is the same as that described for the foam layer 3. However, as a preferred specific example of the PS-based resin, a styrene-butadiene copolymer represented by HIPS is added because the effect of improving the impact resistance of the non-foamed layer (4, 5) is large.

When a modified PPE resin is used as the base resin used in the non-foamed layers (4, 5), the phenylene ether component is preferably 15 to 75 parts by weight, and the styrene component is preferably 75 to 25 parts by weight. And more preferably,
The phenylene ether component is preferably 20 to 60 parts by weight, and the styrene component is preferably 80 to 40 parts by weight. If the use ratio of the PPE-based resin is too small, the heat resistance tends to be poor. If the use ratio of the PPE-based resin is too large, the viscosity during heating and flowing increases, and molding may be difficult.

A preferred heat-resistant PS resin as a base resin for the non-foamed layers (4, 5) is a copolymer of styrene or a derivative thereof and another monomer (hereinafter, referred to as "St copolymer"). As a monomer copolymerizable with styrene or a derivative thereof having an effect of improving heat resistance, for example, maleic acid, fumaric acid, acrylic acid, methacrylic acid, unsaturated carboxylic acid such as itaconic acid or a derivative thereof And nitrile compounds such as acid anhydrides, acrylonitrile and methacrylonitrile or derivatives thereof. These may be used alone or in combination of two or more. The monomer copolymerizable with styrene or a derivative thereof having an effect of improving heat resistance is used in an amount of usually 40% by weight or less, preferably 30% by weight or less.

When polymerizing styrene or a styrene derivative, a polymer obtained by adding a synthetic rubber or rubber latex to an unsaturated carboxylic acid such as maleic acid, fumaric acid, acrylic acid, methacrylic acid or itaconic acid is used. Alternatively, the copolymer may be a derivative thereof and a copolymer thereof with a nitrile compound such as an acid anhydride, acrylonitrile, and methacrylonitrile. Among them, styrene-maleic anhydride-based copolymer, styrene-acrylic acid-based copolymer, styrene-methacrylic acid-based copolymer, acrylonitrile-butadiene-styrene copolymer have the effect of improving heat resistance and versatility. It is preferable from the viewpoint of cost.

The heat-resistant PS resin may be used alone or in combination of two or more. In addition, heat-resistant PS
The system resin may be used by blending with another thermoplastic resin. Examples of the blended thermoplastic resin include polystyrene, HIPS, polycarbonate, polyester,
Polyolefins such as polyethylene and polypropylene,
Examples thereof include vinyl chloride resins such as polyvinyl chloride, polyether ether sulfone, polysulfone, polyamide, and copolymers thereof. Among them, HIPS is preferred from the viewpoints of versatility, uniform dispersion, high effect of improving the impact resistance of the non-foamed layer, cost, and the like.
Known HIPS can be used, and the content of the rubber component is usually 1 to 15% by weight.

The thickness of the non-foamed layers (4, 5) is 50 to 300.
μm, and more preferably 75 to 200 μm. When the thickness of the non-foamed layer (4, 5) is less than 50 μm, the strength,
When the rigidity and heat resistance are poor, and when the thickness is more than 300 μm, the moldability of the laminated sheet tends to be poor.

The present invention also provides a highly foamed foamed layer (3).
The resonance frequency is tuned by adjusting the rigidity and the basis weight of the non-foamed layers (4, 5) by utilizing the sound interference effect due to the vibration of the non-foamed layers (4, 5) laminated on the automobile. This makes it possible to improve the sound absorption performance in the frequency range required as an interior material. Therefore, the basis weight and rigidity of the non-foamed layer are arbitrarily set depending on the frequency region in which the sound absorbing performance is desired to be improved.

Further, for the purpose of broadening the resonance vibration peak in the non-foamed layers (4, 5),
5) An adhesive layer such as a nonwoven fabric such as felt, a foam made of polyurethane foam or a polyolefin foam such as polyethylene or polypropylene, a cushioning material (air cap) having a structure in which air is trapped between non-breathable resin films, etc. The layers may be laminated through the intermediary. In particular, laminating the cushioning material (air cap) on the non-foamed layers (4, 5) is effective because the resonance vibration peak can be broadened at low cost.

When the non-foamed layer (4, 5) is formed, if necessary, an impact resistance improver, a filler, a lubricant, an antioxidant, an antistatic agent, a pigment, a stabilizer, an odor reducing agent, etc. May be added alone or in combination of two or more.

The impact resistance improver is prepared by laminating a non-foamed layer (4, 5) on a foamed layer (3) and forming a secondary foamed laminated sheet as an interior material for an automobile. It is effective to prevent cracking of the non-foamed layer (4, 5) when transporting the molded article or the molded article. Any impact modifier may be used without particular limitation as long as the effect is exhibited by mixing with the base resin. The impact modifier may be a component capable of exhibiting the impact modifying effect introduced into the thermoplastic resin by modification by polymerization. For example, a mixture containing an impact modifying component such as HIPS may be mixed. When used for non-foamed layers,
5) Impact resistance can be imparted.

A hot-melt adhesive layer (6) is formed on the surface of the non-foamed layer (4) on the vehicle interior side of the foam laminated sheet.
The hot melt adhesive is usually used for bonding the skin material (1) to the molded body. Examples of the hot melt adhesive include polyolefin, modified polyolefin, polyurethane, ethylene-vinyl acetate copolymer resin, polyamide, polyester, thermoplastic rubber, styrene-butanediene copolymer, and styrene-isoprene copolymer. Those containing a resin such as a system as a component are exemplified.

As a specific example of the skin material (1), a material used as a conventional automobile interior material can be used. For example, woven fabrics and nonwoven fabrics are provided. These include polyethylene terephthalate, polypropylene, polyamide (nylon), polyacrylonitrile, and modacrylic (for example,
Synthetic resins such as "Kanecaron (registered trademark)" manufactured by Kanegabuchi Chemical Industry Co., Ltd., natural materials such as wool, cotton, and the like, as appropriate, are used. A material obtained by laminating a single layer or multiple layers of a foamed layer made of a polyurethane foam or a polyolefin foam such as polyethylene or polypropylene on the skin material (1), if necessary, can be used.

[0038]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. Table 1 shows the resins used in Examples and Comparative Examples.
In addition, each code regarding the resin shown in Table 1 is as follows.

[0039]

[Table 1] [Type of Resin] Modified PPE: Modified polyphenylene ether PS: Polystyrene SMAA copolymer: Styrene-methacrylic acid copolymer HIPS: High impact polystyrene Evaluation methods performed in Examples and Comparative Examples are shown below. [Expansion ratio] A sample was cut out from a general portion of an automobile interior material, and after separating each constituent layer, the density df of the foamed layer was determined by JI.
It was measured according to SK7222, and the density dp of the modified PPE-based resin was measured according to JIS K7112. Expansion ratio = dp / df

[Mounting Heat Resistance Test] A car interior material (width 930 mm × length 1424 mm) as shown in FIG. 2 was mounted on the ceiling (cut body) of a car, and a sun visor, a room mirror, a room lamp, a ganish, and a pillar were mounted. And fixed so as to be equivalent to the actual vehicle. In the drawings, 7 is an assist grip mounting hole, 8 is a sun visor mounting hole, 9 is a sun visor fixing mounting hole, 10 is a rearview mirror mounting hole, 1
Reference numeral 1 denotes a room light mounting hole. In addition, six measurement points were marked on the front part at intervals of 120 mm symmetrically with the center line of the molded body (a to f in FIG. 1). A marking line was provided near the measurement point in the front part, and the vertical distance was measured. Next, 100 ± 1 ° C
After placing the automobile ceiling with the ceiling material in the constant temperature chamber set for 24 hours, the absolute value of the vertical dimensional change of the measurement point stamped on the front of the molded body was measured, and a to
The maximum value of f was recorded. In addition, the maximum displacement amount entered in Table 3 is a value measured by setting the vertical warping direction to plus (+) and the vertical sagging direction to minus (-).

The following criterion was used in consideration of the practicality as an interior material of an automobile. [Sound Absorbing Property] A test piece was cut out from a general portion of an automobile interior material and evaluated by measuring a normal incidence sound absorbing coefficient according to JIS-A-1405. In addition, in order to approach the state of being mounted on an automobile, a back air layer of 20 mm was provided, and sound was incident from the skin material side. [Air permeability] A test piece was cut out from a general portion of an automobile interior material and evaluated by measuring the air permeability according to JIS-L-1004. The following criterion was used as a criterion for judgment in consideration of practicality as an interior material of an automobile.

[0042]

(Embodiment 1) Foam layer: 40% by weight of PPE resin component, 60% by weight of PS resin component (72.7 parts of modified PPE resin (a) and 27.3 parts of PS resin (b) 5.8 mm thick)
Foamed layer with 32 times expansion ratio Indoor non-foamed layer: PPE resin component 20% by weight, PS resin component 80% by weight (modified PPE resin (a) 28.6)
Part, 71.4 parts of PS resin (b) are mixed).
20 μm film Outdoor non-foamed layer: SMAA copolymer resin (c) 47.5
Part of HIPS resin (d), 47.5 parts of HIPS resin (d), and 5 parts of impact modifier (e). 0 mm) Adhesive layer: A test piece was cut out from a general part of an automobile interior material composed of a hot melt film (Kurabo Co., Ltd., Cranbetter X2200), and the normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

(Example 2) Foamed layer: 40% by weight of PPE resin component, 60% by weight of PS resin component (72.7 parts of modified PPE resin (a) and 27.3 parts of PS resin (b) are mixed) Consisting of 5.1 mm,
A test piece was cut out from a general portion of an automobile interior material having the same configuration as in Example 1 except that the foamed layer had a foaming ratio of 34 times, and the normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

Example 3 Foamed layer: 40% by weight of PPE resin component and 60% by weight of PS resin component (72.7 parts of modified PPE resin (a) and 27.3 parts of PS resin (b) are mixed) A thickness of 5.0 mm,
A test piece was cut out from a general portion of an automobile interior material having the same configuration as in Example 1 except that the foamed layer had a foaming ratio of 42, and the normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

Example 4 Outdoor non-foamed layer: PPE resin component 20% by weight, PS
76.2% by weight of system resin component, 3.8% of rubber component (28.6 parts of modified PPE resin (a), 41.4% of PS resin (b)
Part, 30 parts of HIPS resin (d) are mixed)
A test piece was cut out from a general portion of an automobile interior material having the same configuration as in Example 1 except that the film had a thickness of 20 μm.
The normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

Example 5 A general portion of an automobile interior material having the same structure as that of Example 3 except that a cushioning material (Minapack, a polyethylene foam cushioning material manufactured by Sakai Chemical Industry Co., Ltd.) was laminated on the outdoor skin layer. From Fig. 4, a test piece was cut out, and the normal incidence sound absorption coefficient and air permeability were measured, and the measurement results are shown in Fig. 4 and Table 2. Further, the interior material of the automobile was attached to the cut body, and
A mounting heat resistance test was performed at 0 ° C. for 24 hours. Table 2 shows the measurement results.
Shown in

(Comparative Example 1) Foamed layer: PPE resin component 40% by weight, PS resin component 60% by weight (72.7 parts of modified PPE resin (a) and 27.3 parts of PS resin (b) are mixed) 3.5 mm thick,
A test piece was cut out from a general portion of an automobile interior material having the same configuration as in Example 1 except that the foamed layer had a foaming ratio of 19 times, and the normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

(Comparative Example 2) Foamed layer: PPE resin component 40% by weight, PS resin component 60% by weight (72.7 parts of modified PPE resin (a) and 27.3 parts of PS resin (b) are mixed) 2.2 mm thick,
A test piece was cut out from a general portion of an automobile interior material having the same configuration as in Example 1 except that the foamed layer had a foaming ratio of 12 times, and the normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

(Comparative Example 3) Foamed layer: PPE resin component 40% by weight, PS resin component 60% by weight (72.7 parts of modified PPE resin (a) and 27.3 parts of PS resin (b) are mixed) 1.8 mm thick,
A test piece was cut out from a general portion of an automobile interior material having the same configuration as in Example 1 except that the foamed layer had a foaming ratio of 15 times, and the normal incidence sound absorption coefficient and air permeability were measured. The measurement results are shown in FIG. Further, an automobile interior material was attached to the cut body, and a mounting heat test was performed at 100 ° C. for 24 hours. Table 2 shows the measurement results.

(Comparative Example 4) Foamed layer: PPE resin component 20% by weight, PS resin component 80% by weight (28.6 parts of modified PPE resin (a) and 71.4 parts of PS resin (b) are mixed) Consisting of 5.8 mm,
A foam layer having a foaming ratio of 32 times was used, and an automobile interior material having the same structure as that of Example 1 was attached to the cut body except for the above.
A mounting heat resistance test was performed at 00 ° C. for 24 hours. Table 2 shows the measurement results.

[Table 2]

[0051]

The automotive interior material of the present invention has improved heat resistance, and has improved deformation due to use at high temperatures and droop due to its own weight. In addition, both non-breathability and excellent sound absorption performance, which have been difficult so far, have been achieved.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional explanatory view of a main part of an automobile interior material according to the present invention.

FIG. 2 is an explanatory plan view showing an example of a trimmed automobile interior material according to the present invention.

FIG. 3 shows a measurement result of a normal incidence sound absorption coefficient provided with a 20 mm air layer behind an automobile interior material of Examples 1 to 3 according to the present invention.

FIG. 4 is a graph showing the measurement results of the normal incidence sound absorption coefficient of the vehicle interior materials of Examples 4 and 5 according to the present invention in which an air layer 20 mm behind was provided.

FIG. 5 is a measurement result of a normal incidence sound absorption coefficient of a vehicle interior material of Comparative Examples 1 to 4 according to the present invention in which an air layer 20 mm behind was provided.

[Explanation of symbols]

 1: Skin material 2: Foam laminate 3: Foam layer 4: Non-foam layer inside car 5: Non-foam layer outside car 6: Hot melt adhesive layer 7: Assist grip mounting hole 8: Sun visor mounting hole 9: Sun visor Fastening mounting hole 10: Interior mirror mounting hole 11: Interior light mounting hole

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) JH01 JJ02 JJ03 JL01 JL03 YY00B

Claims (4)

[Claims] 1. An automotive interior material comprising a skin material (1) and a foam laminate (2), wherein the foam laminate (2) is provided on both sides of a foam layer (3) using a modified polyphenylene ether-based resin as a base resin. A non-foamed layer made of a thermoplastic resin (4,
(5) An automobile interior material having a structure in which the foamed layer (3) is laminated, and the foaming ratio of the foamed layer (3) is more than 20 times and 100 times or less. 2. The automotive interior material according to claim 1, wherein the expansion ratio of the foam layer (3) is 25 to 70 times. 3. The automotive interior material according to claim 1, wherein the thermoplastic resin as the base resin of the non-foamed layer (4) is a modified polyphenylene ether-based resin. 4. The modified polyphenylene ether resin as a base resin of the foamed layer (3) has a phenylene ether component content of 35% by weight to 75% by weight and a styrene component content of 65% by weight. The interior material of an automobile according to claim 1, 2 or 3, wherein the content is from 25 to 25% by weight.