JPH1058608A - Manufacture of foamed laminated sheet for automotive vehicle interior material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a foamed laminated sheet for an automotive vehicle interior material at a low cost with high heat resistivity, good dimensional stability, moldability, and an impact resistance. SOLUTION: A foamed laminated sheet for an automotive vehicle interior material is manufactured by extruding a non-foamed layer consisting of a modified polyphenylene ether resin into a film on one surface or both surfaces of a modified polyphenylene ether resin foamed sheet and, in this instance, the non-foamed layer is laminated and subsequently cured to be T2 +130 deg.C<=T<=T1 +170 deg.C in its resin temperature T( deg.C) with respect to the thermal deformation temperature T1 ( deg.C) of the modified polyphenylene ether resin and the thermal deformation temperature T2 ( deg.C) of the modified polyphenylene ether resin, thereby manufacturing a foamed laminated sheet for an automotive vehicle interior material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of manufacturing a foam laminated sheet for an automobile interior material, especially a foam laminated sheet for an automobile ceiling material. More specifically, a non-foamed layer made of a modified PPE resin (II) is formed on one or both sides of a foamed sheet using a modified polyphenylene ether resin (hereinafter also referred to as a modified PPE resin) (I) as a base resin. When manufacturing a foam laminated sheet for automotive interior materials by extruding into the, the resin temperature of the non-foamed layer to a specific temperature,
Preferably, it belongs to the technical field of manufacturing a foam laminated sheet for automotive interior materials, which retains excellent dimensional stability, moldability, and heat resistance by controlling the variation in the width direction to ± 5 ° C. or less.

[0002]

2. Description of the Related Art Conventionally, as interior materials for automobiles, urethane foam laminated on a base material mainly composed of a thermoplastic resin foam, or styrene-maleic anhydride on both 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. And those car interior materials,
It has the features of being lightweight, having high heat insulating properties, and having excellent moldability.

However, when a conventional automobile interior material is used for an application such as an automobile ceiling material which is exposed to a high temperature for a long time, its heat resistance is insufficient, so that it hangs down under its own weight or is deformed. Or may cause problems.

Therefore, in order to improve heat resistance, there has been proposed an automobile ceiling material using a foamed laminated sheet in which a film of a modified polyphenylene ether-based resin is laminated on both sides of a foamed layer of a modified polyphenylene ether-based resin (actually). JP-A-4-11162). This car ceiling material is said to improve the deformation (heat resistance, rigidity, etc.) by using a modified polyphenylene ether-based resin with high heat resistance to reduce deformation under high temperature and sag due to its own weight. Therefore, a non-foamed layer made of a modified polyphenylene ether-based resin is also laminated on both sides of the foamed sheet. In the production of the laminated sheet, a hot press molding method is used in which a foamed layer is extruded in the middle while two films are fed up and down, and they are heat-pressed under predetermined conditions. It is installed as a preferred car ceiling material from the viewpoint of lightness.

[0005] However, in recent years, the price competition of automobiles has intensified, and the price and quality of automobile parts are being reviewed.

[0006]

In the case of the automobile ceiling material, a modified PPE resin previously formed into a film is used in order to improve heat resistance. However, since the resin has high rigidity, it is formed into a film. The processed one has a disadvantage that it is brittle and easily broken. In addition, since the film undergoes stretching during the manufacturing process, it has residual strain, and when hot press molding is performed without removing the residual strain, the film shrinks with cooling after lamination, and the film is molded. There is a disadvantage that the warped sheet is warped. Furthermore, if heating is performed sufficiently during hot press molding to remove residual strain, the heat causes the surface roughness of the non-foamed layer and the tearing of the cell membrane of the foamed layer, and an acceptable molded article cannot be obtained. There are drawbacks.

[0007]

SUMMARY OF THE INVENTION In view of the above circumstances, the present inventor is required to use a modified PPE resin foam laminated sheet as a foam laminated sheet for automobile interior materials such as automobile ceiling materials. In order to satisfy the quality and cost reduction, various examinations were made on the manufacturing conditions when extruding and laminating the modified PPE resin non-foamed layer on both sides or one side of the foamed sheet using a T-die extruder. Intensive studies to develop a foamed laminated sheet for automotive interior materials made of modified polyphenylene ether resin with high dimensional stability, moldability, and impact resistance. The resin temperature at the time of laminating using is set to a specific temperature, and the temperature variation in the width direction is preferably ± 5.
By controlling the temperature to not more than ℃, it is possible to stably laminate in a film shape, without losing the above-mentioned physical properties, moldability, at a low cost, and found that it can be manufactured by simplifying the manufacturing process, The present invention has been completed.

That is, the present invention provides a foamed laminated sheet for automotive interior materials by extruding a non-foamed layer comprising a modified polyphenylene ether-based resin (II) on one or both sides of a foamed sheet of a modified polyphenylene ether-based resin (I). The resin temperature T (° C.) of the non-foamed layer at the time of the production of the modified polyphenylene ether-based resin (I)
₁ (° C) and modified polyphenylene ether resin (I
T ₂ + 130 ° C. ≦ T with respect to the thermal deformation temperature T ₂ (° C.) of I)
≦ T ₁ + 170 ° C., a method for producing a foamed laminated sheet for an automobile interior material, wherein the non-foamed layer is made of a modified polyphenylene ether-based resin (II). 2. The method for producing a foamed laminated sheet for an automobile interior material according to claim 1, wherein the variation in the resin temperature T in the film width direction is ± 5 ° C. or less (claim 2), wherein the modified polyphenylene ether-based resin (II) is a polyphenylene ether-based resin The method for producing a foamed laminated sheet for an automobile interior material according to claim 1 or 2, comprising 25 to 75% (weight%, the same applies hereinafter) and 75 to 25% of a polystyrene resin, and T ₁ ≧ T ₂ . The present invention relates to a method for producing a foamed laminated sheet for an automobile interior material according to claim 1 (claim 4).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a modified PPE resin (I) is used for an automobile interior material in which a non-foamed layer made of a modified PPE resin (II) is extruded into a film on one or both sides of a foamed sheet and solidified by lamination. A foam laminated sheet (primary foam laminated sheet) is manufactured.

As the modified PPE resin (I) for forming the modified PPE resin (I) foamed sheet, a mixed resin of a PPE resin and a polystyrene resin (PS resin);
Copolymers such as grafts and blocks obtained by polymerizing a styrene monomer on a PPE resin are exemplified. Among these, a mixed resin of a PPE-based resin and a PS-based resin is preferred from the viewpoint of easy production.

Examples of the PPE resin include poly (2,6-dimethylphenylene-1,4-ether),
Poly (2-methyl-6-ethylphenylene-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) and poly (2-ethyl-6-chlorophenylene-1,4-ether). These may be used alone or in combination of two or more. Among them, poly (2,6-dimethylphenylene-1,4-ether) is preferable from the viewpoint of versatility of raw materials and cost. Also, if you want to impart flame retardancy,
Poly (2-methyl-6-chlorophenylene-1,4-ether), poly (2-methyl-6-bromophenylene-1,4-ether), poly (2-ethyl-6-) containing a halogen element Chlophenylene-1,4-ether) is preferred.

P which forms a mixed resin with the PPE resin
The S-based resin is a resin containing styrene or a derivative thereof, for example, α-methylstyrene, 2,4-dimethylstyrene, monochlorostyrene, dichlorostyrene, p-methylstyrene, ethylstyrene or the like as a main component (60% or more). . Therefore, the PS resin is not limited to a homopolymer or a copolymer composed of only styrene or a styrene derivative, but may be a copolymer produced by copolymerizing with another monomer. Further, for example, when polymerizing styrene or a styrene derivative, such as high impact polystyrene, a polymer obtained by adding synthetic rubber or rubber latex may be used.

Other monomers copolymerizable with styrene or a derivative thereof which can be used in the production of the PS resin include, for example, acrylonitrile, methacrylonitrile,
Examples include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and maleic anhydride. These may be used alone or in combination of two or more.

Specific examples of the PS resin include polystyrene, styrene-α-methylstyrene copolymer, styrene-butadiene copolymer represented by high impact polystyrene, and styrene-acrylonitrile copolymer. . Among these, polystyrene is preferable in terms of versatility and cost.

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 preferred in terms of versatility and cost.

When the styrene monomer is polymerized on the PPE resin, a monomer copolymerizable with the styrene monomer in a range where the styrene monomer is the main component (60% or more); For example, acrylonitrile, methacrylonitrile,
One or more of methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and maleic anhydride may be contained.

As a method for producing a graft copolymer obtained by polymerizing a PS-based monomer on the PPE-based resin, a conventionally well-known method may be used, for example, Japanese Patent Publication No. 52-30991 and Japanese Patent Publication No. 52-38596. A radical polymerization initiator and a styrene monomer are added to a PPE resin disclosed in a gazette or the like, and the mixture is stirred in a anhydrous state in the presence or absence of an organic solvent in a temperature range of 130 to 200 ° C. A method such as polymerizing a styrene-based monomer may be used.

The PPE resin and the PS resin or PP
The ratio of the styrene-based monomer to be polymerized to the E-based resin (which may contain a monomer copolymerizable with the styrene-based monomer) is preferably a PPE-based resin component of 25 to
For 75%, more preferably 30 to 65%, and particularly preferably 35 to 60%, the PS resin component or PPE
Styrene monomer to be polymerized into the resin is preferably 25.
-75%, more preferably 35-70%, particularly preferably 40-65%. If the proportion of the PPE-based resin is too small, the heat resistance tends to be inferior. If the proportion of the PPE-based resin is too large, the viscosity at the time of heating and flowing increases, and foam molding may become difficult.

The thickness of the primary foamed layer of the foamed sheet of the modified PPE resin (I) using the modified PPE resin (I) as a base resin as described above is 1 to 5 mm, and more preferably 1.5 to 5 mm.
3.5 mm, foaming ratio 3 to 20 times, further 5
~ 15 times, average cell diameter 0.05 ~ 0.9mm,
Furthermore, 0.1 to 0.7 mm, the closed cell rate is 70
% Or more, more preferably 80% or more. Further, the amount of the remaining volatile component in the primary foamed sheet is preferably 1 to 5%, more preferably 2 to 4% based on the total weight of the foamed sheet. The amount of the remaining volatile components is measured, for example, by heating the foamed sheet sample at a temperature not lower than the temperature at which the modified PPE-based resin (I) starts to soften and at a decomposition temperature or lower to sufficiently volatilize the volatile components, and the weight difference before and after heating. Or measured by gas chromatography.

When the thickness of the primary foamed sheet is less than 1 mm, the rigidity is not sufficient and there is a problem in handling. On the other hand, if it exceeds 5 mm, heat will be
It is difficult for the E-based resin (I) to be transmitted to the center in the thickness direction of the foamed layer, so that sufficient heating cannot be performed and moldability may be deteriorated. In addition, if the heating time is extended to perform sufficient heating, cells on the surface of the foam layer may be broken, which may make it difficult to obtain an acceptable product. In addition, when the expansion ratio of the primary foam sheet is less than 3 times, it is inferior in flexibility, is likely to be damaged by bending or the like, and it is difficult to obtain a lightweight one. 20
If the ratio is more than twice, the strength and the moldability tend to decrease due to difficulty in heating to the center. further,
When the average cell diameter is less than 0.05 mm, it is difficult to obtain a molded article having sufficient strength, and when the average cell diameter exceeds 0.9 mm, the obtained molded article tends to have poor heat insulating properties. Also,
When the closed cell ratio is less than 70%, the desired secondary expansion ratio becomes difficult to obtain even by heating for molding, and the heat insulation properties and rigidity of the obtained molded article tend to be inferior. When the residual volatile component is less than 1%, the secondary expansion ratio is too low to be able to be molded satisfactorily. When it exceeds 5%, an air pocket is generated between the non-foamed layer. Or the dimensional stability may deteriorate over time.

The base resin for producing the modified PPE resin (I) foam sheet used in the present invention may contain, if necessary, a cell regulator, an impact modifier, a lubricant, an antioxidant, You may add an antistatic agent, a pigment, etc.

The modified PPE resin (I) foam sheet (primary foam sheet) is a mixed resin of a PPE resin and a PS resin or a copolymer obtained by copolymerizing a PPE resin with a styrene monomer. If necessary, the mixture containing various additives is melted and kneaded by an extruder at 150 to 400 ° C., and then 100 parts of resin (parts by weight, hereinafter referred to as 150 to 400 ° C. and 30 to 500 atm. Foaming agent 1)
~ 15 parts by press-fitting, foaming optimum temperature (190-210 ° C)
And extrude it into a low pressure range (usually in the atmosphere)
It is manufactured by a method such as forming into a sheet shape with a mandrel or the like while taking it up under a condition of 0.5 to 4.0 m / min. When forming the sheet, it is desirable to cool the foamed sheet with an air ring or the like in order to suppress primary foaming on the foamed sheet surface. In the case of insufficient cooling, the primary foaming of the foamed sheet surface is not suppressed, the thickness of the cell membrane is reduced, and the foamed sheet surface is heated by laminating a non-foamed layer on the foamed sheet surface in a later step. Of the primary foamed laminated sheet may be reduced, and it may be difficult to obtain an acceptable product as a product.

As the foaming agent used in producing the modified PPE resin (I) foam sheet, there may be mentioned hydrocarbon-based foams such as butane, propane, pentane, methyl chloride, dichloromethane, chlorofluoromethane, dichloroethane and dichlorodifluoroethane. Foaming agents, halogenated hydrocarbon-based foaming agents, and the like. These may be used alone or in combination of two or more. Among them, hydrocarbon blowing agents are preferred from the viewpoint of versatility and cost.

A non-foamed layer of the modified PPE resin (II) is formed on one or both sides of the primary foam sheet as described above.
When the modified PPE-based resin (II) non-foamed layer is formed only on one side of the primary foamed sheet, the weight is reduced, the process for manufacturing the primary foamed laminated sheet is short and simple, and the material cost is low. This is preferable because the production cost is reduced as a whole. On the other hand, when a modified PPE resin (II) non-foamed layer is formed on both surfaces, it has high rigidity, excellent heat resistance and dimensional stability, and can be used for items with large interior members such as wagons. preferable.

As the modified PPE resin (II) forming the non-foamed layer, as in the case of the primary foam sheet, a PPE resin and a polystyrene resin (PS resin)
And copolymers such as grafts and blocks obtained by polymerizing a styrene-based monomer with a PPE-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 of the PPE-based resin, preferred examples, specific examples of the PS-based resin, preferred examples, preferred examples of the styrene-based monomer, preferred examples, and further include a styrene-based monomer contained in the PS-based resin. Specific examples of the monomer that can be polymerized with the body are the same as those in the case of the primary foam sheet, and thus description thereof is omitted. However, as a preferred specific example of the PS resin, a styrene-butadiene copolymer represented by high impact polystyrene is added because the effect of improving the impact resistance of the non-foamed layer is large.

The ratio of the PPE resin and the PS resin or the styrene monomer polymerized to the PPE resin in the modified PPE resin (II) non-foamed layer is as follows.
The styrene-based monomer to be polymerized into the PS-based resin or the PPE-based resin is preferably 75 to 25%, more preferably 70 to 30% with respect to the PE-based resin 25 to 75%, more preferably 30 to 70%. If the proportion of the PPE-based resin is too small, the heat resistance of the molded article tends to be inferior. If the proportion of the PPE-based resin is too large, the viscosity at the time of heating and flowing increases, which may make extrusion molding difficult. .

Further, the closed cell rate of the primary foam laminated sheet after laminating the non-foamed layer is 70% or more, and more preferably 80% or more.
% Or more is preferable. When the closed cell rate of the primary foam laminated sheet is less than 70%, the heat insulating property and the rigidity tend to be inferior, and it is difficult to obtain a sufficient secondary expansion ratio at the time of mold molding heating, and the moldability tends to be inferior. Occurs.

The thickness of the non-foamed layer is 50 to 300 μm,
Furthermore, 75 to 200 μm is preferable. When the thickness of the non-foamed layer is less than 50 μm, strength, rigidity, heat resistance and the like tend to be inferior, and when the thickness is more than 300 μm, moldability tends to be inferior. When a non-foamed layer is provided on both surfaces (upper and lower surfaces) of the primary foam sheet, the thickness of the non-foamed layer is preferably 50 to 200 μm, and a non-foamed layer is provided on one of the upper and lower surfaces. In such a case, the thickness of the non-foamed layer is preferably from 75 to 300 μm.

When the modified PPE-based resin (II) non-foamed layer is formed, the modified PPE-based resin (II) non-foamed layer may be provided with an impact resistance improver, An agent (for example, an inorganic filler), a lubricant, an antioxidant, an antistatic agent, a pigment, and the like may be added alone or in combination of two or more.

The impact resistance improver is formed by laminating a modified PPE resin (II) non-foamed layer on a modified PPE resin (I) foamed sheet and subjecting it to secondary foaming to form a foam laminated sheet for automotive interior materials. When transporting the body or performing further punching on the foam laminated sheet molded body for automotive interior materials,
It is a component used to prevent cracking of the non-foamed layer.

According to the study of the present inventor, the reason that the non-foamed layer is apt to be cracked is that the foamed layer depends on its material properties.
This is probably because the non-foamed layer absorbs impact and is hardly damaged, but the non-foamed layer has a small impact absorbing power and is easily damaged when subjected to stress concentration due to bending or impact. Therefore, when an impact resistance improver is added to the non-foamed layer where stress concentration is applied, the flexibility and impact resistance of the non-foamed layer are improved, and damage due to bending and impact is prevented. I found it.

The impact resistance improver is not particularly limited as long as it exhibits its effect by being mixed with the base resin or is capable of exhibiting its effect by being polymerized into the base resin. sell. For example, when a PS resin containing an impact resistance improving component is used as the PS resin used for modifying the PPE resin, such as impact-resistant polystyrene, the modified PPE resin (II) non-foamed layer should have a high impact resistance. Can be provided.

Examples of the impact modifier include rubbers such as natural rubber and synthetic rubber, and monomers having an olefin double bond such as styrene and methyl methacrylate grafted around rubber particles. Those and the like are preferably used.

Specific examples of the rubber include styrene-butadiene rubber, butadiene rubber, isoprene rubber, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, acrylonitrile-butadiene copolymer, chloroprene rubber, and butyl rubber. , Urethane rubber, silicone rubber, polysulfide rubber, hydrogenated nitrile rubber, special polyether rubber, fluoro rubber, ethylene tetrafluoride-propylene rubber, acrylic rubber, chlorosulfonated polyethylene rubber, epichlorohydrin rubber, propylene oxide rubber , Ethylene-acrylic rubber, liquid rubber, norbornene rubber, styrene-based thermoplastic elastomer, olefin-based thermoplastic elastomer, urethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polyamide Thermoplastic elastomers, 1,2
Polybutadiene-based thermoplastic elastomer, PVC-based thermoplastic elastomer, fluorine-based thermoplastic elastomer, MB
S resin, ethylene-vinyl acetate copolymer and the like. These may be used alone or in combination of two or more. Of these, styrene-butadiene rubber is preferred from the viewpoint of high compatibility with the modified PPE-based resin and versatility.

The addition amount of the impact modifier is preferably 2 to 25%, more preferably 4 to 20%, based on the PPE resin.
If the impact resistance improver is less than 2%, the effect of improving the flexibility and impact resistance of the non-foamed layer will not be sufficiently exhibited, and breakage due to bending or impact will not be sufficiently prevented. When the amount of the impact resistance improver exceeds 25%, heat resistance and rigidity tend to be inferior.

The filler is a component used for improving strength, rigidity, dimensional stability and the like, and the filler used is not particularly limited. Specific examples of the filler include talc (magnesium silicate), calcium carbonate (heavy, light, colloid, etc.), mica, magnesium oxide, magnesium carbonate, barium sulfate, calcium sulfate, calcium sulfite, silica, clay, kaolin , White carbon, magnesium hydroxide, carbon black, zeolite, molybdenum and the like. Of these, talc, calcium carbonate and mica are particularly preferred.

The amount of the filler to be added is as follows.
The amount is 1 to 50 parts, preferably 5 to 40 parts with respect to 00 parts. When this addition amount is less than 1 part, filler (inorganic)
Cannot be obtained, and if added over 50 parts, the impact strength of the non-foamed layer is significantly reduced. Further, the viscosity of the resin composition increases, and a large load is applied to the extruder, which is not preferable.

A preferred specific example of the primary foam laminated sheet in which the modified PPE resin (I) has a non-foamed layer formed on one or both sides of the foamed sheet of the modified PPE resin (I) is the modified PPE resin described above. It is a combination of (I) a preferred example of a foamed sheet and a modified PPE-based resin (II) a preferred example of a non-foamed layer.

As a method for extruding and laminating a non-foamed layer made of the modified PPE resin (II), a modified PPE resin sheet which has been foam-formed in advance is fed out, and various additives are added to both surfaces or one surface of the primary foam sheet. It is preferable that the modified PPE-based resin is heated and melted (plasticized) by an extruder, extruded into a film by a T-die, laminated, and pressed by a cooling roll. Among them, a method of extruding a primary foam sheet of a foam layer and extruding a non-foam layer in-line and laminating them is particularly preferable. Further, the temperature of the cooling roll is preferably set to a temperature at which the non-foamed layer does not fuse to the roll surface, and is equal to or lower than the thermal deformation temperature of the non-foamed layer.

Resin temperature T during extrusion of non-foamed layer to be laminated
(° C.) is the thermal deformation temperature of the modified PPE resin (I) of the foamed sheet T ₁ (° C.), and the modified PPE resin (I) of the non-foamed layer is
Assuming that the thermal deformation temperature of I) is T ₂ (° C.), T ₂ + 130 ° C.
≦ T ≦ T ₁ + 170 ° C., preferably T ₂ + 140 ° C. ≦ T ≦
T ₁ + 160 ° C. When the resin temperature T is lower than T ₂ + 130 ° C., the flexibility of the non-foamed layer and the adhesion between the foamed sheet and the non-foamed layer are inferior. When the resin temperature T is higher than T ₁ + 170 ° C., This leads to breakage of the cell membrane on the surface of the foamed sheet, and the moldability of the primary foam laminated sheet is reduced, and the molding area is narrowed.

The heat distortion temperature is a value measured under a load of 18.6 kgf / cm ² according to ASTM D648.

[0043] Also, preferably T ₁ ≧ T _2, and more preferably a T _1> T _2. In this case, damage to the foamed layer during heating during molding can be reduced, and a foamed laminated sheet molded article for interior materials for automobiles having more excellent moldability and heat resistance can be obtained. If T ₁ > T ₂ , T ₁ is T ₂
It is particularly preferred that the temperature is + 4 ° C. or higher.

In the present invention, the variation in the resin temperature in the width direction of the film when forming the non-foamed layer is preferably ± 5 ° C. or less. When the variation in the resin temperature in the width direction of the film exceeds ± 5 ° C., the resin fluidity in the T-die becomes non-uniform, and the variation in the lamination thickness (film thickness) of the non-foamed layer tends to increase. As a result, heating unevenness is likely to occur during molding, and molding failure is likely to be induced. The variation of the resin temperature T is particularly preferably ± 2 ° C. or less.

The variation in the resin temperature in the width direction of the film is 270 mm from the center of the T-die of the resin of the non-foamed layer discharged from the outlet of the T-die slip, two points at both ends, and the center. The average value (root mean square) of the resin temperature was obtained from the value measured by a method of reading the resin temperature by putting the sensor part of the thermometer into the resin for the non-foaming layer at a total of five points at two positions in the width direction. (A value obtained by adding ± to the value of a large difference among the differences between the highest value or the lowest value and the average value).

The resin temperature T is usually 230 to 320 ° C. in view of the flexibility of the non-foamed layer, the adhesion between the primary foamed sheet and the non-foamed layer, and the breaking of the cell membrane on the surface of the primary foamed sheet. Is preferably 240 to 310 ° C.

The above T ₁ is usually from 110 to 150 ° C., more preferably from 120 to 140 ° C., and T ₂ is usually from _{100 to 1} ° C.
50 ° C, further 110-140 ° C. T ₁ is 11
If the temperature is lower than 0 ° C., the heat resistance tends to be inferior, and 150 ° C.
In some cases, the ratio of the PPE-based resin is too high and extrusion foaming becomes difficult. When T ₂ is less than 100 ° C., the heat resistance tends to be inferior, and when T ₂ exceeds 150 ° C., extrusion of the non-foamed layer may become difficult.

In the present invention, the resin temperature T of the non-foamed layer is
It is controlled by controlling the T-die and the heater for heating the extruder. As a control method of a heater for heating a T die and an extruder, there are a heater heating ON-OFF control method and a heater current variable control method which are generally used. Reduce temperature variations, eg ± 2 ° C
The variable heater current control method is preferable from the viewpoint that the temperature can be controlled within the range. Above all, P (proportional) I (integral)
A system combining D (differential) operation is preferable because variation in heater heating capacity (heater current) can be controlled to be small.

A skin material may be laminated on the primary foam laminated sheet as needed.

As a specific example of the skin material, there is a skin material such as a woven fabric or a nonwoven fabric, which is a skin material used as a conventional automobile interior material. These may be those using synthetic resins such as polyethylene terephthalate, polypropylene, polyamide, polyacrylonitrile, nylon, and the like, or natural materials such as wool and cotton, or a combination thereof. Also,
A foamed layer may be laminated instead of the woven or nonwoven fabric, or a foamed layer of urethane or polyolefin may be laminated between the woven or nonwoven fabric and the primary foam laminated sheet.

When flame retardancy is required for the foam laminated sheet for automobile interior materials of the present invention, it is preferable to use a skin material provided with flame retardancy.

In the present invention, as a specific method for bonding the skin material, a method in which an adhesive is previously attached to the skin material is bonded to the primary foamed laminated sheet using a hot roll or the like. A method of laminating an adhesive that has been processed into a film shape beforehand on the next foam laminated sheet by a binder lamination method or a heat lamination method, and then bonding the skin material using a heat roll, etc., bonding the skin material to the primary foam laminated sheet Examples of the method include a method of temporarily fixing via a material and simultaneously forming and bonding at the time of heat molding, and a method of simultaneously laminating and bonding a skin material when laminating an adhesive on a primary foam laminated sheet.

Examples of the adhesive include a thermoplastic adhesive, a hot melt adhesive, a rubber adhesive, a thermosetting adhesive, a monomer reactive adhesive, an inorganic adhesive, and a natural adhesive. However, a hot melt adhesive is preferred because it can be easily bonded.

Examples of the hot melt adhesive include polyolefin, modified polyolefin, polyurethane, and the like.
Examples thereof include resins containing resins such as an ethylene-vinyl acetate copolymer, a polyamide, a polyester, a thermoplastic elastomer, a styrene-butadiene copolymer, and a styrene-isoprene copolymer. These may be used alone or in combination of two or more.

The foam laminated sheet for automobile interior materials manufactured by the present invention is the primary foam laminated sheet as described above. The primary foam laminated sheet is heated and secondary foamed, and molded using a mold. The molded secondary foam laminate sheet obtained is used as an interior material for automobiles.

As a method of manufacturing a molded secondary foam laminated sheet which is a molded article of a foam laminated sheet for an automobile interior material from the primary foam laminated sheet, a heating furnace having upper and lower heaters is heated at a temperature suitable for molding. For example, 120-300 ° C
After heating the heating furnace, the primary foam laminated sheet is clamped to the center of the heating furnace, guided, heated and subjected to secondary foaming, and then vacuum-molded or air-pressure molded in a temperature-controlled mold. Examples of vacuum forming and compressed air forming include plug forming, free drawing forming, plug and ridge forming, ridge forming,
Examples include methods such as matched mold molding, straight molding, drape molding, reverse draw molding, air slip molding, plug assist molding, and plug assist reverse draw molding. Of these, plug molding, matched
A method capable of changing the mold clearance, such as molding, is preferable.

It is preferable that the primary foamed laminated sheet be molded in a state before a keloid state is generated on the surface of the primary foamed laminated sheet by heating in the molding. As a result of the study of the present inventors, it has been found that when molding is performed in a state where a keloid state is generated on the surface during molding heating, the closed cell ratio is reduced and the rigidity of the molded body is reduced. The keloid state is caused by the foam breaking of the foamed layer, and therefore, the closed cell rate is reduced.

As in the case of straight molding, secondary molding may be carried out using a mold having only one mold, followed by molding.

Thus, preferably 2 to 10 mm
A foamed laminated sheet molded article for automobile interior materials (a secondary foamed laminated sheet molded article) having a thickness of 2 mm is manufactured.

The thickness of the formed secondary foam laminated sheet is 2.0 to 10 mm, preferably 3.0 to 8 mm.
mm, the expansion ratio (secondary expansion ratio) with respect to the primary foam sheet is 1.2 to 4 times, further 1.5 to 3 times, and the average cell diameter is 0.1 to 2.0 mm, and more preferably 0.1 to 2.0 mm. 2
1.6 mm, the closed cell rate is 60% or more, and more preferably 70% or more.

When the thickness of the formed secondary foam laminated sheet is less than 2.0 mm, strength and heat insulation are poor, and the molded article may not be suitable as a foam laminated sheet molded article for automobile interior materials. On the other hand, if it exceeds 10 mm, the inside of the vehicle tends to be unnecessarily bulky and narrow. When the secondary expansion ratio is less than 1.2 times, the flexibility is inferior and breakage due to bending or the like is likely to occur. On the other hand, if it exceeds 4 times,
The strength tends to decrease. Furthermore, when the average cell diameter is 0.
When it is less than 1 mm, it is difficult to obtain sufficient strength as a foamed molded article, and when it is more than 2.0 mm, the heat insulating property tends to be poor. Furthermore, the closed cell rate of the molded article is 60%.
If it is less than 30, rigidity tends to be inferior.

In the method of the present invention for producing a foamed laminated sheet for an automotive interior material using the modified PPE resin as a base resin, a modified PPE resin ( For example, when the modified PPE-based resin (II) is extruded into a film and extruded into a film and laminated, the resin temperature in the T-die is regulated to a predetermined range. However, since a method is preferably adopted in which the variation in the resin temperature in the film width direction is set to ± 5 ° C. or less, the adhesiveness between the foamed sheet and the non-foamed layer is good, and the unevenness during molding is not uniform. A primary foam laminated sheet without secondary foaming, surface roughness, and uneven molding can be obtained at low cost and with a simplified production process.

[0063]

EXAMPLES The production method of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Table 1 shows the resins used in the examples and comparative examples.

[0065]

[Table 1]

In Table 1, the PPE resin component is a polymer of 2,6-dimethylphenylene-1,4-ether, the PS resin component is polystyrene, and the rubber component is styrene-butadiene rubber.

In the examples and comparative examples, the non-foamed layer resin temperature variation in the width direction, heat deformation temperature, adhesiveness,
The heating test and the uneven thickness ratio of the non-foamed layer were evaluated according to the following methods.

(Non-foaming layer resin temperature T and variation in width direction) Two points at both ends, one point at the center, and the center of the non-foaming layer resin discharged from the exit of the T die slip (1080 mm width) Thermometer (DIGITAL SUR manufactured by Anritsu Keiki Co., Ltd.)
The sensor part of FACE THERMOMETER was put in the non-foamed layer resin, and the resin temperature was measured. The root mean was performed from the measured five resin temperatures to obtain the resin temperature T. In addition, the maximum or minimum value of the five resin temperatures and the resin temperature T
(Average value) and the difference in the width direction, which is a value obtained by adding ± to the value of the large difference, was determined.

(Heat Deformation Temperature) According to ASTM D648 (load: 18.6 kgf / cm ² ).

(Adhesiveness) The primary foam laminated sheet was 540 m
m (extrusion direction of the primary foam laminated sheet) × 540 mm (1
(Width direction of the next foam laminated sheet)
After heating to a surface temperature of 150 ° C., the test piece was taken out of the furnace, and visually observed whether or not there was peeling due to generation of bubbles between the non-foamed layer and the foamed layer. The evaluation was based on the following criteria.

：: No bubbles were generated and no peeling was observed. ×: Air bubbles are generated and peeling is observed.

(Heating test) The primary foamed laminated sheet was 540
mm (extrusion direction of primary foam laminated sheet) x 540 mm
(To the width direction of the primary foam laminated sheet)
After placing in a heating furnace at 50 ° C. and heating to a surface temperature of 150 ° C., the test piece was taken out of the heating furnace, and the surface roughness of the entire non-foamed layer was visually observed and evaluated according to the following criteria.

：: No surface roughness (keloid state) is observed on the entire surface. Δ: Surface roughness (keloid state) occurs partially, and cannot be used in actual use. ×: Surface roughness (keloid state) was observed on the entire surface, and it could not withstand actual use.

(Thickness deviation of non-foamed layer)
A 25 mm wide kraft adhesive tape (manufactured by Nitto Denki Kogyo Co., Ltd.) is stuck on the next foam sheet so as to be perpendicular to the extrusion direction of the primary foam sheet without wrinkling. Laminated. After that, cut off the non-foamed layer at the place where the kraft tape is stuck, and dial thickness gauge (Teclock dial thickness gauge)
The thickness was measured at 36 points at equal intervals of 30 mm using the following formula.

[0075]

(Equation 1)

From the above, the thickness deviation rate of the non-foamed layer was calculated.

Example 1 A mixed resin obtained by mixing 72.7 parts of the modified PPE resin (A) and 27.3 parts of the PS resin (C) so that the PPE resin component was 40% and the PS resin component was 60% ( T ₁ 124
C.) 100 parts by weight, 3 parts of a blowing agent containing iso-butane (iso / n = 85/15) and 0.32 part of talc were heated and kneaded with an extruder.
It was cooled to 98 ° C., extruded from a circular die, cut open, and wound up on a take-up roll via a take-up roll at a speed of 5 m / min.

The obtained primary foam sheet has a thickness of 2.6 m.
m, width 1080 mm, primary expansion ratio 10 times, average cell diameter 0.19 mm, basis weight 240 g / m ² , closed cell rate 83
% Foam sheet.

The obtained primary foamed sheet was fed at 5 m / min, and a PPE resin component 30% and a PS resin component 64
%, The modified PPE resin (A) so that the rubber component is 6%.
And a mixed resin (T ₂ 117 ° C.) obtained by mixing the PS resin (B) and the impact resistance improving agent (C) are melted and kneaded at a resin temperature of 270 ° C., and extruded into a film shape using a T-die having a width of 1080 mm. A non-foamed layer having a thickness of 150 μm was laminated on one side of the foamed sheet. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 2 ° C. After laminating the non-foamed layer, it was pressed and solidified at a cooling roll temperature of 60 ° C., and the obtained primary foamed laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Example 2 A primary foam sheet was produced by the method described in Example 1 and wound into a roll.

The obtained primary foamed sheet was fed out, and the same mixed resin for the non-foamed layer as used in Example 1 was melted and kneaded at a resin temperature of 285 ° C., and formed into a film using a T-die having a width of 1080 mm. And a non-foamed layer having a thickness of 150 μm was laminated on one side of the primary foam sheet. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 2 ° C. After laminating the non-foamed layer, it was pressed and solidified at a cooling roll temperature of 60 ° C., and the obtained primary foamed laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Example 3 A PPE resin component and a PS resin component each contained 55
% And 45 parts of the modified PPE resin (A) per 100 parts of a foaming agent containing iso-butane as a main component (is
3 parts of o-butane / n-butane = 85/15) and 0.32 part of talc were added and kneaded at 315 ° C. by an extruder.
The resin was cooled until the resin temperature reached 205 ° C., extruded from a circular die, cut open, and wound up on a take-up roll via a take-up roll at a speed of 5 m / min.

The obtained primary foam sheet has a thickness of 2.3 m.
m, width 1080 mm, primary expansion ratio 10 times, average cell diameter 0.17 mm, basis weight 240 g / m ² , closed cell rate 83
%Met.

While feeding the obtained primary foamed sheet at a speed of 5 m / min, the modified PPE resin is adjusted so that the PPE resin component, the PS resin component and the rubber component become 40%, 54% and 6%, respectively. (a), PS resin (B) and the impact modifier (C) the mixture was mixed resin (T ₂ 1
24 ° C.) at a resin temperature of 300 ° C.
A non-foamed layer having a thickness of 150 μm was laminated on one side of the primary foam sheet by extruding the film into a film shape using a 0-mm T die. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 2 ° C. After laminating a non-foamed layer, cooling roll temperature 60 ° C
, And the obtained primary foam laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Example 4 A primary foam sheet was produced by the method described in Example 3 and wound into a roll.

While feeding the obtained primary foam sheet at a speed of 5 m / min, the modified PPE resin is adjusted so that the PPE resin component, the PS resin component and the rubber component become 25%, 69% and 6%, respectively. A mixed resin obtained by mixing (A), PS resin (B) and impact resistance modifier (C) is melted and kneaded at a resin temperature of 250 ° C., and extruded into a film shape using a T-die having a width of 1080 mm, and primary foaming is performed. A non-foamed layer having a thickness of 150 μm was laminated on one side of the sheet. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 2 ° C. After laminating the non-foamed layer, it was pressed and solidified at a cooling roll temperature of 60 ° C., and the obtained primary foamed laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Example 5 A primary foam sheet was produced by the method described in Example 1 and wound into a roll. The obtained primary foamed sheet was fed out, and the same non-foamed layer mixed resin used in Example 1 was melted and kneaded at a resin temperature of 270 ° C., and extruded into a film shape using a T-die having a width of 1080 mm. Next, a non-foamed layer having a thickness of 150 μm was laminated on one surface of the foamed sheet. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 7 ° C. After laminating a non-foamed layer, it is solidified by compression at a cooling roll temperature of 60 ° C,
The obtained primary foam laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Example 6 A primary foam sheet was produced by the method described in Example 1 and wound into a roll. The obtained primary foamed sheet was fed out, and the same non-foamed layer mixed resin as used in Example 1 was melted and kneaded at a resin temperature of 285 ° C., and extruded into a film shape using a T-die having a width of 1080 mm. Next, a non-foamed layer having a thickness of 150 μm was laminated on one surface of the foamed sheet. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 7 ° C. After laminating a non-foamed layer, it is solidified by compression at a cooling roll temperature of 60 ° C,
The obtained primary foam laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Comparative Example 1 A primary foam sheet was produced by the method described in Example 1 and wound into a roll.

The obtained primary foamed sheet was fed out, and the same mixed resin for the non-foamed layer as used in Example 1 was melted and kneaded at a resin temperature of 300 ° C., and formed into a film using a T-die having a width of 1080 mm. And a non-foamed layer having a thickness of 150 μm was laminated on one side of the primary foamed sheet. At this time, T is adjusted so that the variation in the resin temperature in the film width direction becomes ± 7 ° C.
The die heater temperature was adjusted. After laminating a non-foamed layer, it was pressed and solidified at a cooling roll temperature of 60 ° C.
Next, the foamed laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

Comparative Example 2 A primary foam sheet was produced by the method described in Example 1 and wound into a roll.

The obtained primary foamed sheet was fed out, and the same mixed resin for the non-foamed layer as used in Example 1 was melted and kneaded at a resin temperature of 245 ° C., and a film was formed using a T-die having a width of 1080 mm. And a non-foamed layer having a thickness of 150 μm was laminated on one side of the primary foam sheet. At this time, the temperature of the T-die heater was adjusted so that the variation in the resin temperature in the film width direction was ± 7 ° C. After laminating the non-foamed layer, it was pressed and solidified at a cooling roll temperature of 60 ° C., and the obtained primary foamed laminated sheet was wound into a roll.

A test piece was cut out from the obtained roll-shaped primary foam laminated sheet, and the adhesion, the heating test, and the uneven thickness ratio of the non-foamed layer were evaluated. Table 2 shows the results.

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[Table 2]

From the results shown in Table 2, it can be seen that the primary foamed laminated sheets obtained in Examples 1 to 4 have no practical problems and are excellent in moldability.

[0103]

According to the method of the present invention for producing a foamed laminated sheet for an automobile interior material, a non-foamed layer of a modified PPE resin having a high heat resistance in a plasticized state is processed into a film in a separate step in advance. Since it is directly laminated on the primary foamed sheet at a specific resin temperature without any problem, the adhesive strength between the foamed layer and the non-foamed layer is improved, and a foamed laminated sheet for automotive interior materials having good moldability can be obtained. Moreover, according to the production method of the present invention, a film production facility in a separate process is not required, the production method is simplified, and it is economically excellent, and an easily stable foam laminated sheet for automobile interior materials can be obtained. Provided.

Claims (4)

[Claims] When a non-foamed layer made of a modified polyphenylene ether-based resin (II) is extruded into a film on one or both sides of a foamed sheet of a modified polyphenylene ether-based resin (I), a foamed laminated sheet for an automobile interior material is produced. non-foamed layer of the resin temperature T (° C.) is, with respect to thermal deformation temperature T ₂ of the thermal deformation temperature T ₁ of the modified polyphenylene ether resin (I) (℃) and modified polyphenylene ether resin (II) (℃) of T ₂ + 130 ° C ≦ T ≦ T ₁ + 170 ° C.
A method for producing a foamed laminated sheet for an automobile interior material, comprising laminating and solidifying the laminate. 2. A modified polyphenylene ether resin (I)
The method for producing a foamed laminated sheet for an automobile interior material according to claim 1, wherein a variation in the resin temperature T of the non-foamed layer formed in I) in the film width direction is ± 5 ° C or less. 3. A modified polyphenylene ether resin (I)
I) is a polyphenylene ether resin 25 to 75% by weight
The method for producing a foamed laminated sheet for an automobile interior material according to claim 1 or 2, comprising 75 to 25% by weight of a polystyrene resin. 4. The method according to claim 1, wherein T ₁ ≧ T ₂ .