JP2000289137A - Laminated foam sheet for car interior material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a subject laminated foam sheet capable of preventing the peel of a skin material at high temp. SOLUTION: An adhesive resin layer 18 with an m.p. of 100-160 deg.C and having crystallinity with energy of crystallization of 35-100 J/g is formed on a laminated foam sheet 10 wherein non-foamed layers 14 comprising a thermoplastic resin as a substrate resin is laminated on both surfaces of a foam layer 12 comprising a heat-resistant resin as a substrate resin. An adhesive resin layer 18 comprising a laminated film of a polyolefinic film and a polystyrenic film is formed on the laminated foam sheet 10 so that the polystyrenic film comes into contact with the surface of the non-foamed layer of the laminated foam sheet 10. Further, a skin material 20 is laminated through the adhesive resin layer 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated foam sheet for an automobile interior material, and more particularly, to a laminated foam for an automobile interior material which is excellent in heat resistance and lightness by preventing peeling of a skin material at a high temperature. It is about the seat.

[0002]

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

However, when the above-mentioned conventional laminated foam sheet for an automobile interior material is used for an application that is exposed to a high temperature for a long time, the heat resistance is insufficient, so that the sheet falls under its own weight, Problems such as deformation were sometimes caused.

[0004] In order to solve these problems,
Lamination for automotive interior materials using a foamed laminated sheet in which a non-foamed layer of a modified PPE-based resin is laminated on both sides of a foamed layer of a lightweight, heat-resistant modified polyphenylene ether-based resin (hereinafter referred to as “modified PPE-based resin”) A foam sheet has been proposed (Japanese Utility Model Laid-Open No. 4-1162). This laminated foam sheet for automobile interior materials is said to improve deformation under high temperature and sag due to its own weight by using a modified PPE-based resin having high heat resistance.

[0005] On the other hand, in laminating a car interior material with a skin material formed using a modified PPE foam laminated sheet, a polyolefin hot melt agent is frequently used as an inexpensive and moderately heat-resistant adhesive. In addition, a polyolefin resin as a base resin maintains adhesion to various skin materials. On the other hand, the adhesiveness to an automobile interior base material is maintained by an amide-based or ester-based additive. However, at present, adhesiveness with a skin material that can withstand a high temperature of about 100 ° C. has not been obtained.

[0006]

SUMMARY OF THE INVENTION In view of the above situation, the present invention uses a heat-resistant resin-laminated foamed sheet so that it can be manufactured inexpensively and easily while maintaining light weight and heat resistance. Provided is a laminated foamed sheet for an automobile interior material which can prevent the peeling of a skin material or the like at a time.

[0007]

The present inventor provides a molded article for a laminated foam sheet for an automobile interior material which has excellent adhesion to a skin material, has a light weight, is inexpensive, and can be easily manufactured. Therefore, as a result of intensive research to develop a laminated foam sheet for automotive interior materials, first, in order to maintain heat resistance at high temperatures in a single-layer hot melt film, it is necessary to select an appropriate base resin Thereby, the heat resistance can be maintained by the melting point, and the adhesive stability can be obtained by the crystal energy, and the adhesive has stable adhesiveness even at a high temperature. There is a limit to the improvement of adhesiveness by additives. Then, it was found that high-temperature adhesiveness could be further obtained by using a laminated film composed of a polyolefin-based film and a polystyrene-based film. That is, the present inventors have found that a polyolefin film having crystallinity produces stable adhesiveness to a skin material, and that a stable heat fusion with the substrate can be achieved by using a polystyrene film of the same type as the substrate, and completed the present invention. I came to.

That is, the present invention relates to (1) a foamed laminated sheet in which a non-foamed layer made of a thermoplastic resin is laminated on both sides of a foamed layer made of a heat-resistant resin as a base resin, An automotive interior material laminated foam sheet having an adhesive resin layer having a crystallinity of 100 JC to 160 C and a crystallization energy of 35 J / g to 100 J / g (Claim 1). 2. The foamed laminated foam sheet for an automobile interior material according to claim 1, wherein the adhesive resin layer having the adhesive resin layer is a hot melt adhesive based on a polyolefin-based resin (claim 2). A foamed laminated sheet in which a non-foamed layer made of a thermoplastic resin is laminated on both sides of a foamed layer made of a resin, and an adhesive resin layer made of a laminated film of a polyolefin-based film and a polystyrene-based film, The automobile according to claim 3, wherein the laminated foam sheet for an automobile interior material is formed so that the Tylene-based film is in contact with the surface of the non-foamed layer of the foamed laminated sheet (Claim 3), and the (4) polyethylene-based film is used as the polyolefin-based film. The laminated foam sheet for an interior material of an automobile according to claim 3 or 4, wherein the polyethylene-based film is made of a linear low-density polyethylene-based resin (claim 5). 6) The laminated foam sheet for an automotive interior material according to any one of claims 3 to 5, wherein the thickness of the polyolefin-based film is 15 to 100 μm (claim 6), and (7) the polystyrene-based film is made of a high-impact polystyrene-based resin. Claims 3 to 6
The laminated foam sheet for an automobile interior material according to any one of (7) and (8), wherein the thickness of the polystyrene film is 10 to 10.
The laminated foam sheet for an automobile interior material according to any one of claims 3 to 7, wherein the heat-resistant resin as a base resin of the foamed layer has a phenylene ether component content of 35 µm. The laminated foam sheet for an automobile interior material according to any one of claims 1 to 8, wherein the modified polyphenylene ether resin is a modified polyphenylene ether-based resin having a content of styrene-based component of 65 to 25% by weight. (9) and (10) a skin material made of a polyethylene terephthalate-based fiber nonwoven fabric is further formed on the surface of the adhesive resin layer.
The present invention relates to a laminated foam sheet for an automobile interior material according to any one of claims 1 to 9 (Claim 10).

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a laminated foam sheet for an automobile interior material according to the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the configuration of a laminated foam sheet 10 for an automobile interior material according to one embodiment of the present invention. A thermoplastic resin is applied to both sides of a foam layer 12 having a heat-resistant resin as a base resin. Non-foamed layer (base non-foamed layer 14)
And a non-foamed layer 16 on the outside of the vehicle, and a skin material 20 is laminated on the lower surface of the non-foamed layer 14 on the inside of the vehicle via an adhesive resin layer 18.

The heat-resistant resin used as the base resin of the foamed sheet of the present invention has a Vicat softening temperature (JIS K7).
A resin having a heat resistance of at least 100 ° C. (measured according to the Vicat softening temperature test method (method B) of thermoplastic resin 206) can be used. For example, heat-resistant polystyrene resin 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 (hereinafter, PPE) , A modified polyphenylene ether resin (modified PPE resin) such as a styrene-phenylene ether copolymer such as a styrene graft polymer onto PPE; a polycarbonate resin; and a polyester resin exemplified by polybutylene terephthalate and polyethylene terephthalate. is there. Two or more of these resins can be used.

Of these, the use of a modified PPE-based resin as a base resin for a foamed sheet is preferable because it has excellent heat resistance and rigidity, and is easy to process and easy to manufacture.

The PPE used for the modified PPE resin is, for example, poly (2,6-dimethylphenylene-1,1).
4-ether), poly (2-methyl-6-ethylphenylene-1,4-ether), poly (2,6-diethylphenylene-1,4-ether), poly (2,6-diethylphenylene-1,4-ether) 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 may be used alone or in combination of two or more.

Among the modified PPE resins, a polystyrene resin (hereinafter referred to as “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-methylstyrene, ethylstyrene and the like. 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, 35 to 75 parts by weight of the phenylene ether component and 65 to 25 parts by weight of the styrene component are used. Preferably, more preferably 35 parts by weight to 60 parts as phenylene ether component
Parts by weight, 65 to 40 parts by weight as a styrene component,
Particularly preferably, a phenylene ether component of 38 to
58 parts by weight and 62 to 42 parts by weight as the styrene component are preferred. If the proportion of the PPE-based resin is small, the heat resistance tends to be inferior. If the proportion of the mixed proportion component of the PPE-based resin is large, the viscosity at the time of heating and flowing increases, and foam molding tends to be difficult.

The primary foamed layer forming the foamed layer 12 using a heat-resistant resin as a base resin has a thickness of 1 to 5 mm,
Further, 1.5 to 3.5 mm, foaming ratio is 3 to 20 times, further 5 to 15 times, cell diameter is 0.05 to 0.9 mm, further 0.1 to 0.7 mm, closed cell rate is It is preferably at least 70%, more preferably at least 80%. When the thickness of the primary foamed layer is less than 1 mm, the strength and the heat insulating property are poor, and it may not be suitable as a laminated foamed sheet for automobile interior materials. On the other hand, when it exceeds 5 mm, heat is applied to the
Is difficult to transmit to the center in the thickness direction, so that sufficient heating cannot be performed and moldability may be deteriorated. In addition, if the heating time is increased to perform sufficient heating, cells on the surface of the foam layer may be broken, and it may be difficult to obtain an acceptable product. If the primary expansion ratio is less than 3 times, the flexibility is poor, the breakage due to bending or the like is likely to occur, and the effect of reducing the weight is small. If the primary expansion ratio exceeds 20 times, the strength tends to decrease and the moldability tends to decrease due to the difficulty in heating to the center. Further, when the cell diameter is 0.05 mm or less, it is difficult to obtain sufficient strength,
When it is 0.9 mm or more, the heat insulating property tends to be poor. When the closed cell ratio is 70% or less, heat insulation and rigidity are poor, and it is difficult to obtain a desired secondary expansion ratio by molding and heating, and the moldability tends to be poor.

The amount of the volatile component remaining in the primary foamed layer forming the foamed layer 12 using the heat-resistant resin as the base resin is 1 to 5% by weight, more preferably 2 to 4% by weight, based on the total weight of the foamed layer. % By weight is preferred. If the residual volatile component is less than 1% by weight, the secondary expansion ratio becomes too low, and good molding may not be achieved. On the other hand, when the residual volatile component exceeds 5% by weight, an air pocket may be generated between the non-foamed layer and the dimensional stability over time. Incidentally, the amount of the remaining volatile components may be measured by gas chromatography,
Usually, the foamed layer sample is heated in a temperature range not lower than the temperature at which the heat-resistant resin starts to soften and not higher than the decomposition temperature to sufficiently volatilize the volatile components, and the measurement is made based on the weight difference before and after the heating.

The base resin of the foamed layer 12 used in the present invention may contain, if necessary, a cell regulator, an impact modifier, a lubricant, an antioxidant, an antistatic agent, a pigment, a stabilizer, an odor, and the like. You may add a reducing agent etc.

In the laminated foam sheet for an automobile interior material according to the present invention, non-foamed layers 14 and 16 of a thermoplastic resin are formed on both sides of a foamed layer 12 having a heat-resistant resin as a base resin. Of these non-foamed layers 14 and 16,
Has a function of suppressing the heat shrinkage of the skin material 20 laminated on one surface thereof, and a function of suppressing the thermal expansion due to the expansion of the cell diameter of the foam layer 12 on the other surface under heating. The non-foamed outside layer 16 has a function of suppressing the thermal expansion of the foamed layer 12.

Next, examples of the thermoplastic resin used for the non-foamed layers 14 and 16 include a heat-resistant PS-based resin and a modified PPE resin, and these may be used alone or in combination of two or more. When a modified PPE-based resin is used as the foamed layer 12, a modified PPE-based resin or a heat-resistant PS-based resin is preferably used from the viewpoint of adhesion to the resin layer.

When a modified PPE-based resin is used as the non-foamed layer 14 on the inside of the vehicle, the P
The PE resin is modified by polymerization or mixing with a monomer mainly composed of a styrene compound or a polymer thereof. For example, a mixed resin of a PPE resin and a PS resin, a styrene resin as a PPE resin. -Styrene copolymer obtained by polymerizing a resin monomer, a mixture of the copolymer and a PS resin or a PPE resin, and the copolymer and PPE
And a mixture of a PS resin and a PS 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 the monomer that can be polymerized with the base resin and the St monomer, and the reason for using the same are the same as those described for the foam layer 12. 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 layers 14 and 16 is large.

When a modified PPE resin is used as the base resin used for the non-foamed layer 14 on the inside of the vehicle, 10 to 50 parts by weight of the phenylene ether component and 90 to 50 parts by weight of the styrene component are preferable. Preferably,
10 to 45 parts by weight as a phenylene ether component, 90 to 55 parts by weight as a styrene component, particularly preferably,
The phenylene ether component is preferably 15 to 40 parts by weight, and the styrene component is preferably 85 to 60 parts by weight. If the use ratio of the PPE resin is too small, the heat resistance tends to be inferior,
If the use ratio of the PPE-based resin is too large, the viscosity at the time of heating and flowing may increase, and extrusion molding may be difficult.

It is preferable to use a heat-resistant polystyrene (PS) resin as the base resin for forming the non-foamed layer 16 on the outside of the vehicle. The heat-resistant PS-based resin is a copolymer of styrene or a derivative thereof and another monomer, and a monomer copolymerizable with styrene or a derivative thereof having an effect of improving heat resistance is, for example, maleic acid. And unsaturated carboxylic acids such as fumaric acid, acrylic acid, methacrylic acid and itaconic acid or derivatives thereof, and acid anhydrides thereof, and nitrile compounds such as 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. Further, when polymerizing styrene or a styrene derivative, one obtained by adding a synthetic rubber or rubber latex and polymerizing the same and an unsaturated carboxylic acid such as maleic acid, fumaric acid, acrylic acid, methacrylic acid, itaconic acid or a derivative thereof. And a copolymer thereof with a nitrile compound such as an acid anhydride, acrylonitrile, and methacrylonitrile. Among them, styrene-maleic anhydride copolymer, styrene-
Acrylic acid-based copolymers, styrene-methacrylic acid-based copolymers, and acrylonitrile-butadiene-styrene copolymers are preferred in view of the heat resistance improving effect, versatility, and cost.

The heat-resistant PS resin may be used alone or in combination of two or more. In addition, heat-resistant PS
The thermoplastic resin may be blended with another thermoplastic resin, and the thermoplastic resin to be blended may be, for example, polystyrene, HIPS, polyolefin such as polyethylene or polypropylene, vinyl chloride resin such as polyvinyl chloride, or a copolymer thereof. Polymers. Among these, HIPS is preferred from the viewpoints of versatility, uniform dispersion, high effect of improving the impact resistance of the non-foamed layer 16 on the outside of the vehicle, cost, and the like. Known HIPS can be used, and the content of the rubber component is usually 1 to 15% by weight.

Next, the thickness of the non-foamed layers 14, 16 is 50 to
It is preferably 300 μm, more preferably 75 to 200 μm. If the thickness of the non-foamed layer is less than 50 μm, the strength, rigidity,
When the heat resistance is poor and the thickness is more than 300 μm, the moldability of the laminated sheet tends to be poor.

Next, a method for producing the laminated foam sheet 10 for an automobile interior material of the present invention will be described. The foamed layer 12 (primary foamed layer) used in the present invention is obtained by extruding a heat-resistant base resin to which various additives have been added by an extruder at 150 ° C to 400 ° C.
Melting and kneading at 150 ° C., then 150-400 ° C., 3-50
Under high temperature and high pressure of MPa, foaming agent 1 to 100 parts of resin
15 parts are press-fitted, adjusted to the optimum foaming temperature (150 to 300 ° C), extruded into a low pressure zone (usually in the atmosphere) using a circular die, etc., and then brought into contact with a mandrel, etc.
For example, it can be manufactured by a method such as forming into a sheet while drawing at a speed of 0.5 to 40 m / min, cutting, and winding.

Examples of the foaming agent used for producing the foamed layer 12 include hydrocarbon-based foaming agents such as butane, propane and pentane. These may be used alone or in combination of two or more.

The non-foamed thermoplastic resin layer 14
As a method of laminating 16, a resin molded in a film shape in advance is bonded to the upper surface and / or lower surface of the foamed layer 12 supplied by foam molding with a hot roll or the like, using a multilayer extrusion die. Co-extrusion laminating method, etc. may be mentioned.
It is preferable that the resin composition for a non-foamed layer supplied from an extruder is layered on the upper surface and / or lower surface of the resin layer, and the non-foamed layers 14 and 16 in a plastic state are fixed by a cooling roller or the like. Above all, a method in which the extrusion foam sheet forming of the foam layer 12 and the extrusion of the non-foam layers 14 and 16 are performed in-line and laminated are preferable in that the manufacturing process can be simplified.

As a method of forming a molded secondary foam laminate as an automobile ceiling material from the obtained primary foam laminate sheet, a foam laminate sheet is clamped and guided to the center of a heating furnace having heaters above and below. After heating to a temperature suitable for molding, for example, 120 to 200 ° C. to cause secondary foaming,
It is molded in a temperature-controlled mold. Examples of molding include vacuum molding, air pressure molding, plug molding, free drawing molding, plug and ridge molding, ridge molding, matched molding, straight molding, drape molding, reverse draw molding, air slip molding, plug assist Molding, plug assist reverse draw molding, and the like.

When the above (primary) foam sheet is subjected to heating and secondary foaming, the primary foam sheet (expansion ratio: 3 to 20) is used.
Times, preferably 5 to 15 times, thickness: 1 to 5 mm, preferably 1.5 to 3.5 mm), and usually 1.2 to 4 times.
Although the secondary foaming is performed twice, it is further preferable that the secondary foaming is performed 1.5 to 3 times. (As a result, the sheet magnification after the secondary foaming is 3.6 to 80 times, preferably 7.5 to 7.5 times.) 45 times,
Particularly preferably, it is 10 to 40 times, and the thickness is 1.2 to 20.
0 mm, preferably 2.25 to 10.5 mm, particularly preferably 3.0 to 7.0 mm).

In the molding of the secondary foam laminated molded article,
It is preferable to mold the foamed laminated sheet in a state before a keloid state is generated on the surface of the laminated sheet by heating. If molding is performed in a state where a keloid state has occurred on the surface during molding heating, the closed cell ratio decreases, and the rigidity of the molded body decreases. The keloid state is caused by the foam breaking of the foamed layer, and therefore, the closed cell rate is reduced.

When the laminated foam sheet for an automobile interior material, which is a molded secondary foam laminate molded article, has a skin, the production method is to use a material in which an adhesive resin layer 18 has been applied to a skin material 20 in advance. A method in which the adhesive resin layer 18 is bonded to the foamed laminated sheet using a heat roll or the like, and the adhesive resin layer 18 is laminated on the primary foamed laminated sheet by the binder lamination method or the adhesive resin layer 18 previously formed into a film shape by the heat lamination method. A method of bonding the skin material 20 to the foam laminated sheet using a heat roll or the like, a method of temporarily fixing the skin material 20 to the primary foam laminated sheet, and simultaneously performing the molding and the adhesive resin layer 18 during the heat molding, When laminating the layer 18 on the primary foam laminated sheet, a method of simultaneously bonding the skin material 20 and the like can be used.

The adhesive resin layer 18 is used for bonding the skin material 20 to the molded body when the laminated foam sheet for an automobile interior material has a skin. By laminating the adhesive resin layer 18, a skin of the adhesive resin layer 18 due to a contraction of the adhesive resin layer 18 at the time of heating, an air pocket between the non-foamed layer 14 and the adhesive resin layer 18, etc. Poor adhesion of the material 20 can be prevented. In addition, by forming the adhesive resin layer 18 on the foam laminated sheet (10) in advance, the step of temporarily fixing the adhesive resin layer 18 during molding can be omitted, and the cost can be reduced.

As a specific example of the skin material 20, a material used as a conventional automobile interior material can be used. For example, woven fabrics and non-woven fabrics are provided. These include synthetic resins such as polyethylene terephthalate, polyamide (nylon), polyacrylonitrile, and modacrylic (for example, "Kanecaron (registered trademark)" manufactured by Kaneka Chemical Co., Ltd.), wool, and the like. A natural material such as cotton or a combination of them is used as appropriate.If necessary, a foamed layer made of a polyolefin foam such as polyethylene or polypropylene may be further added to the skin material 20 as a single layer or a multilayer. Can be used.

When flame retardancy is required for the laminated foam sheet for automotive interior materials 10 of the present invention, it is preferable to use a skin material 20 having flame retardancy.

When the crystalline adhesive resin layer 18 used in the present invention is a hot melt adhesive, the melting point (J
IS K 7121 is preferably 100 ° C. or more and 160 ° C. or less. Further, from the viewpoint of moldability and thermal cost at the time of secondary molding to obtain a secondary foam laminated molded article, the melting point is 10%.
The temperature is more preferably 0 ° C or more and 125 ° C or less. When the melting point is lower than 100 ° C., the skin material 20 peels off at a high temperature of 100 ° C. in the obtained laminated foam sheet for automobile interior material. If the melting point is higher than 160 ° C., the skin material 20
It is necessary to increase the temperature at which the adhesive resin layer 18 melts, that is, the heating temperature of the laminated foam sheet for an automobile interior material on which the adhesive resin layer 18 is laminated, in order to impart adhesion to the adhesive sheet.
The foamed layer of the laminated foam sheet for automotive interior materials breaks, resulting in poor appearance and reduced rigidity of the laminated foam sheet for automotive interior materials.

The adhesive resin layer 18 having the crystallinity
Means that its crystallization energy (measured according to the method of measuring the transition temperature of JIS K 7121 plastic) is 35 J /
g or more. Furthermore, it is preferable that it is 35 J / g or more and 100 J / g or less. When the crystal energy is less than 35 J / g, the adhesion stability between the laminated foam sheet for automobile interior materials and the skin material is poor, and the skin material may peel off. On the other hand, when the crystallization energy is larger than 100 J / g, the laminated foam sheet for automotive interior materials is subjected to secondary molding to impart adhesion to the skin material 20.
A large amount of heat is required to heat the laminated foam sheet for an automobile interior material on which the adhesive resin layer 18 is laminated when obtaining the next foam laminated molded article.

When a laminated film is used as the crystalline adhesive resin layer 18 used in the present invention, a polyolefin film is disposed on the skin material 20 side, and a polystyrene film is disposed on the indoor non-foamed layer 14 side. It is preferable to use a laminated film composed of a polyolefin-based film and a polystyrene-based film.

It is preferable to use a polyolefin-based film in order to exhibit good adhesion to the skin material 20. More preferably, a polyethylene film such as a linear low-density polyethylene resin is used. Since the linear low-density polyethylene resin has crystallinity and can stably maintain a low-viscosity state by heating, an anchor effect with the skin material is effectively exerted, and strong adhesion with the skin material 20 is obtained. Show.

The thickness of the polyolefin film is 15 to
It is preferably 100 μm, more preferably 20 to 50 μm. When the thickness of the polyolefin-based film is smaller than 15 μm, the polyolefin-based film reduced in viscosity by heating does not penetrate into the skin material 20,
An appropriate anchor effect cannot be exhibited, and good adhesion to the skin material is not shown. On the other hand, when it is thicker than 100 μm, a large amount of the polyolefin-based film whose viscosity has been reduced by heating penetrates the skin material 20 and deteriorates the feel of the skin material.

In the bonding on the non-foamed layer side, it is preferable to use the same type of polystyrene film for effective thermal bonding. It is preferable to use a high-impact polystyrene resin because distortion during molding can be suppressed.

The thickness of the polystyrene film is 10 to 1
The thickness is preferably 00 μm, more preferably 20 to 50 μm. If the thickness of the polystyrene-based film is less than 10 μm, stable adhesiveness with the non-foamed layer cannot be obtained. On the other hand, if it is thicker than 100 μm, a large amount of heat can give a stable adhesiveness to the non-foamed layer, but will cause a significant decrease in productivity.

Although various embodiments of the laminated foam sheet for automobile interior materials according to the present invention have been described above, the present invention is not limited to the above embodiments. For example, the laminated foam sheet for an automobile interior material can be used as a laminated foam sheet for an interior material such as a train as an application, and should be interpreted in a broad sense. In addition, the present invention is based on the knowledge of those skilled in the art without departing from the spirit thereof, and various improvements,
The present invention can be implemented in a modified or modified mode.

[0046]

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.

[0047]

[Table 1] [Types of Resin] Modified PPE: Modified polyphenylene ether PS: Polystyrene SMA copolymer: Styrene-maleic anhydride copolymer HIPS: High impact polystyrene Evaluation methods performed in Examples and Comparative Examples are shown below. [Thickness of foam layer and molded article] The thickness of the primary foamed sheet and the molded article at 20 locations in the width direction was measured, and the average of the measured values was calculated. [Expansion ratio] Determine the density df of the primary foam sheet according to JIS K
The density dp of the modified PPE resin was measured according to 7222.
Was measured in accordance with JIS K 7112, and determined by the following equation. Expansion ratio = dp / df [Independent cell ratio] It was determined by evaluating according to ASTM D-2859 (using a multi-pycnometer (manufactured by Beckman)). [Cell Diameter] The cross section of the foamed layer was observed with an optical microscope, the diameters of 20 cells were measured, and the average of the measured values was calculated. [Eye weight] From 5 places in the extrusion direction of the primary foam sheet,
Cut out a test piece of 100 mm x 100 mm in size,
After measuring their weight, the average value was calculated. [Appearance of foamed laminated sheet at the time of secondary molding] Before the plug molding, the appearance of the foamed laminated sheet for the laminated foamed sheet for automotive interior materials subjected to secondary heating was visually observed and recorded. [Skin material adhesion test] As shown in FIG. 2, a laminated foam sheet 22 for automobile interior materials (width 930 mm × length 1424 m)
m) was mounted on the ceiling (cut body) of an automobile, and fixed via a sun visor, a room mirror, a room lamp, a ganish, and a pillar so as to be equivalent to an actual vehicle. In addition,
In the figure, 24 is an assist grip mounting hole, 26 is a sun visor mounting hole, 28 is a sun visor fixing mounting hole, 30 is a room mirror mounting hole, and 32 is a room light mounting hole. Then, 1
After putting the automobile ceiling with the laminated foam sheet for automobile interior material into the constant temperature room set at 00 ± 1 ° C., the skin material at the front end and rear end of the molded body after 2 hours and 24 hours The peeled state was visually observed and recorded.

[0048]

Example 1 A mixed resin 100 obtained by mixing 57.1 parts of a PPE resin (A) and 42.9 parts of a PS resin (B) so as to have a PPE resin component of 40% by weight and a PS resin component of 60% by weight.
Parts of the foaming agent containing iso-butane as a main component (is
(o-butane / n-butane = 85/15) 3.4 parts and talc 0.34 parts were kneaded by an extruder, extruded by a circular die, and taken up through a take-up roll at a speed of 8 m / min. Wound into a roll, primary thickness 2.4 mm, primary expansion ratio 12 times, closed cell ratio 90%,
A foam sheet having a cell diameter of 0.19 mm and a basis weight of 180 g / m2 was obtained. Next, the foamed sheet is rolled for 5
While feeding at a speed of m / min, 43.9 parts of a styrene-maleic anhydride copolymer (C) and HIPS (D)
9 parts and 12.2 parts of impact modifier (E) (total rubber component 1)
0 wt%) and a resin temperature of 245 ° C.
The mixture is melted and kneaded with an extruder and extruded into a film using a T-die.
m heat-resistant PS resin non-foamed layer was formed. Further, while the sheet on which the PS resin non-foamed layer having improved heat resistance is formed is unwound from a roll at a speed of 5 m / min, the PPE
PPE resin (A) 42.9 parts, PS resin (B) 45.6 parts, impact resistance 30% by weight of PS resin, 63.1% by weight of PS resin, and 6.9% by weight of rubber The mixed resin obtained by mixing 11.5 parts of the property improver (E) is melted and kneaded with an extruder so that the resin temperature becomes 275 ° C., extruded into a film shape using a T die, and the other side of the foam laminated sheet is formed. A modified PPE-based resin non-foamed layer having a thickness of 120 μm was formed on the substrate, and a foamed laminated sheet having a non-foamed layer laminated on both sides was obtained.

On the other hand, low-density PE (Sumikacene F1103, manufactured by Sumitomo Chemical Co., Ltd.) was added to 60% by weight of hot melt material (Cranbetter X2200, manufactured by Kurabo Co., Ltd.).
Extruding a mixed resin having a melting point of 102% by weight.
A hot melt film having a thickness of 30 μm and comprising a polyethylene resin having a crystallization energy of 85.3 J / g at a temperature of 8 ° C. was obtained.

The foamed laminated sheet is fed out, and at the same time, the modified P
The hot melt film is unwound as an adhesive resin layer on the PE resin non-foamed layer side, and the surface temperature is 120 ° C., 10 m
And wound up via a heat roll adjusted to a speed of / min to obtain a primary foam laminated sheet having an adhesive resin layer formed on the surface of the non-foamed layer of the modified PPE resin. On the surface of the adhesive resin layer of the primary foam laminated sheet, four sides of the primary foam laminated sheet having a skin material in which a PET nonwoven fabric skin material (RVC-100 manufactured by Japan Vilene Co., Ltd., about 1 mm thick) is temporarily fixed are clamped. And put it in the oven, and the foamed laminated sheet surface temperature is 140 ° C
Was heated for 60 seconds. Then, the modified PPE-based resin non-foamed layer is placed in the mold so as to be on the inside of the vehicle, plug-molded with a mold clearance of 5.0 mm, trimmed and punched, and a laminated foam sheet for automotive interior materials is obtained. Was. The obtained laminated foam sheet for an automobile interior material was mounted on a cut body, and a skin material adhesion test was performed at 100 ° C. after 2 hours and 24 hours after mounting. Table 2 shows the results.

[0051]

[Table 2]

[0052]

Example 2 A urethane-based adhesive was formed by bonding a 25 μm thick linear low density polyethylene (Sumikasen FZ103 manufactured by Sumitomo Chemical Co., Ltd.) film and a 25 μm thick high impact polystyrene (Stylon 475D manufactured by Asahi Kasei Corporation) film. A laminated foam sheet for an automobile interior material was obtained in the same manner as in Example 1, except that an adhesive resin layer composed of a laminated film dry-laminated with an agent was used. The obtained laminated foam sheet for an automobile interior material was subjected to a skin material adhesion test on mounting heat resistance in the same manner as in Example 1. Table 2 shows the results.

[0053]

Example 3 A 50 μm thick linear low-density polyethylene film (Sumikasen FZ103 manufactured by Sumitomo Chemical Co., Ltd.) and a 25 μm thick high impact polystyrene (Stylon 475D manufactured by Asahi Kasei Corp.) film were used. A laminated foam sheet for automotive interior materials was obtained in the same manner as in Example 1 except that an adhesive resin layer composed of a laminated film dry-laminated with an adhesive was used. The obtained laminated foam sheet for an automobile interior material was subjected to a skin material adhesion test on mounting heat resistance in the same manner as in Example 1. Table 2 shows the results.

[0054]

Example 4 A linear low-density polyethylene film (Sumikasen FZ103 manufactured by Sumitomo Chemical Co., Ltd.) having a thickness of 25 μm and a high impact polystyrene (Stylon 475D manufactured by Asahi Kasei Corporation) film having a thickness of 10 μm were mixed with a urethane-based film. A laminated foam sheet for automotive interior materials was obtained in the same manner as in Example 1 except that an adhesive resin layer composed of a laminated film dry-laminated with an adhesive was used. The obtained laminated foam sheet for an automobile interior material was subjected to a skin material adhesion test on mounting heat resistance in the same manner as in Example 1. Table 2 shows the results.

[0055]

Comparative Example 1 A foam laminated sheet was obtained in the same manner as in Example 1. Next, in the same manner as in Example 1, a 30 μm-thick hot melt film made of a polyethylene resin having a melting point of 94 ° C. and a crystallization energy of 42.1 J / g (Cranbetter X2200 manufactured by Kurabo Industries, Ltd.) ) Was used as an adhesive layer to obtain a laminated foam sheet for an automobile interior material in the same manner as in Example 1. The obtained laminated foam sheet for an automobile interior material was subjected to a skin material adhesion test on mounting heat resistance in the same manner as in Example 1. Table 2 shows the results.

[0056]

Comparative Example 2 Low-density polyethylene film (Sumikasen L705 manufactured by Sumitomo Chemical Co., Ltd.) having a thickness of 25 μm and ethylene-vinyl acetate copolymer (Evaflex manufactured by DuPont-Mitsui Polychemical Co., Ltd.) having a thickness of 25 μm A laminated foamed sheet for automotive interior materials was obtained in the same manner as in Example 1 except that an adhesive resin layer composed of a laminated film obtained by dry laminating with a urethane-based adhesive was used. Example 1 of the obtained laminated foam sheet for automobile interior materials
In the same manner as in the above, a skin material adhesion test at mounting heat resistance was performed.
Table 2 shows the results.

[0057]

According to the present invention, when an adhesive resin layer having a specific melting point and crystallization energy and having crystallinity is used, it is possible to obtain high-temperature adhesion stability and low-cost adhesion. it can. When a specific laminated film is used as the adhesive resin layer having crystallinity,
Since the function can be separated for the adhesion of the different materials such as the skin material and the base material, it is possible to further reduce the cost and obtain higher adhesiveness.

[Brief description of the drawings]

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

FIG. 2 is an explanatory plan view showing an example of a laminated foam sheet for an automobile interior material subjected to a trimming process according to the present invention.

[Explanation of symbols]

 10: Laminated foam sheet for automotive interior materials 12: Foam layer 14: Non-foam layer inside the vehicle 16: Non-foam layer outside the vehicle 18: Adhesive layer 20: Skin material 22: Molded product for automotive interior material 24: Assist grip mounting hole 26: Sun visor mounting hole 28: Sun visor fixing jig mounting hole 30: Room mirror mounting hole 32: Interior light mounting hole a to f: Front end portion of molded body for automobile interior material g ~ l: Automotive interior material Rear end of molded body

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B32B 27/36 B32B 27/36 C08L 71/12 C08L 71/12 // C08J 9/04 CEZ C08J 9/04 CEZ 101 101 C08L 25/04 C08L 25/04

Claims (10)

[Claims] 1. A foamed laminated sheet in which a non-foamed layer made of a thermoplastic resin is laminated on both sides of a foamed layer made of a heat-resistant resin as a base resin, has a melting point of 100 ° C. or more and 160 ° C. or less, And a crystallization energy of 35 J / g or more and 100 J /
An automotive interior material laminated foam sheet having an adhesive resin layer having crystallinity of not more than g. 2. The foamed laminated foam sheet for an automobile interior material according to claim 1, wherein the adhesive resin layer having crystallinity is a hot melt adhesive based on a polyolefin resin. 3. A foamed laminated sheet in which a non-foamed layer having a thermoplastic resin as a base resin is laminated on both sides of a foamed layer having a heat-resistant resin as a base resin, a polyolefin-based film and a polystyrene-based film A laminated foam sheet for an automobile interior material in which an adhesive resin layer composed of a laminated film is formed such that a polystyrene film is in contact with the surface of the non-foamed layer of the foam laminated sheet. 4. The laminated foam sheet for an automobile interior material according to claim 3, wherein a polyethylene film is used as the polyolefin film. 5. The laminated foam sheet for an automobile interior material according to claim 3, wherein the polyethylene-based film is made of a linear low-density polyethylene-based resin. 6. The polyolefin-based film having a thickness of 15
The laminated foam sheet for an automobile interior material according to any one of claims 3 to 5, wherein the thickness is from 100 to 100 µm. 7. The laminated foam sheet for an automobile interior material according to claim 3, wherein the polystyrene-based film is made of a high-impact polystyrene-based resin. 8. A polystyrene film having a thickness of 10 to 10.
The laminated foam sheet for an automobile interior material according to any one of claims 3 to 7, which is 100 µm. 9. The heat-resistant resin as the base resin of the foamed layer has a phenylene ether component content of 35% by weight to 75% by weight and a styrene component content of 65% by weight to 25% by weight.
The laminated foam sheet for an automobile interior material according to any one of claims 1 to 8, which is a modified polyphenylene ether-based resin in an amount of 1% by weight. 10. The laminated foam sheet for an automobile interior material according to claim 1, wherein a skin material made of polyethylene terephthalate-based nonwoven fabric is further formed on the surface of the adhesive resin layer.