JP2010274545A - Automotive member and manufacturing method thereof - Google Patents

Abstract

The present invention provides an automobile member that has excellent bonding strength, can reduce variations in adhesive force, and does not cause interface peeling even when exposed to a use environment for a long time, and a method for manufacturing the same.
A metal core material 2, an adhesive layer 3 formed on the metal core material 2, and a polyolefin resin composition layer 4 laminated on the metal core material 2 with the adhesive layer 3 interposed therebetween. The adhesive layer 3 is a mixture of 70 to 99% by mass of a polypropylene resin modified with maleic anhydride and 1 to 30% by mass of a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. Do it. The thickness of the adhesive layer 3 is 0.1 to 10 μm. The polyolefin resin composition layer 4 is preferably made of TPO (thermoplastic polyolefin) or crystalline PP (crystalline polypropylene).
[Selection] Figure 1

Description

  The present invention relates to an automobile member including an automobile molding such as a belt line molding, a window molding, and a side molding, and a manufacturing method thereof.

Conventionally, automotive parts such as belt moldings, window moldings, side moldings, and other automobile moldings have been widely adopted in which a metal such as aluminum or stainless steel is used as a core and the core is covered with a vinyl chloride resin. I came.
However, polyolefin resins such as TPO (thermoplastic polyolefin) and crystalline PP (crystalline polypropylene) have been studied as coating resins to replace vinyl chloride resin due to environmental problems such as the occurrence of dioxins in vinyl chloride resin. Yes.

  As a means of resin coating on the metal core material, an aluminum alloy profile or a long plate of aluminum alloy or stainless steel is formed (for example, bent by roll forming) and then introduced into the die of a resin kneading extruder. Composite extrusion molding in which resin layers are joined in a die is widely performed. Usually, in order to increase the bonding strength between the metal core material and the coating resin, a bonding agent layer is interposed at the interface between them.

  In automotive parts, attempts have been made to improve coating resins with the aim of improving scratch resistance, preventing cracking during use due to residual stress during extrusion, and improving adhesion to metal cores. ing. Specifically, for example, in order to prevent cracks from occurring, a polyolefin resin having a low bending elastic modulus is specified (Patent Document 1), for improving scratch resistance, and for improving adhesion to a metal core, The thing (patent document 2) which uses the polymer composition of the specific ratio of an olefin type thermoplastic elastomer and ethylene type ionomer resin is proposed.

JP 2003-226202 A JP 2003-237495 A

  Usually, a modified polyolefin adhesive or a urethane adhesive is used as an adhesive interposed between the metal core material and a coating resin such as a polyolefin resin. However, when these adhesives are applied, depending on the usage environment, it may be a long time depending on the thermal strain at the time of composite molding with the metal core material by the kneading extruder and the residual stress strain due to bending. It has been found that there is a problem in that peeling occurs at the interface between the metal core material and the adhesive layer.

  The present invention has been made in view of such conventional problems, and is excellent in strength between the metal core material and the resin composition layer, can reduce variations in adhesive force, and is exposed to a use environment for a long time. It is an object of the present invention to provide an automobile member that does not cause interfacial peeling even if it is applied, and a method for manufacturing the same.

The first invention comprises a metal core, an adhesive layer formed on the metal core, and a polyolefin resin composition layer laminated on the metal core via the adhesive layer,
The adhesive layer is prepared by mixing 70 to 99% by mass of a polypropylene resin modified with maleic anhydride and 1 to 30% by mass of a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. And
The thickness of the said adhesive bond layer is 0.1-10 micrometers, It exists in the motor vehicle member characterized by the above-mentioned (Claim 1).

  According to a second aspect of the present invention, a dispersion containing a PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin is applied to a metal core, dried, and then the above. According to another aspect of the present invention, there is provided a method for manufacturing an automobile member, wherein the metal core material is molded, and then the polyolefin resin composition is coated on the metal core material through the dispersion.

  According to a third aspect of the present invention, a dispersion containing a PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin is applied to a metal core, dried, and then the above. An automobile member manufacturing method is characterized in that a metal core material is coated with the polyolefin resin composition via the dispersion, and thereafter the metal core material is molded.

The remarkable point of the automobile member of the first invention is that an adhesive layer having the above-described specific configuration is provided between the metal core material and the polyolefin resin composition layer.
The PP resin alone modified with maleic anhydride can obtain the initial adhesion between the metal core material and the polyolefin resin composition layer, but the adhesion to the metal core material is significantly reduced at low temperatures. is there.
Moreover, the styrene-isoprene-butadiene block copolymer and the styrene-α-olefin copolymer do not lose flexibility even in a low-temperature environment and hardly crack.

  And the adhesive layer is blended at a specific ratio by combining the polypropylene resin modified with maleic anhydride and the styrene-isoprene-butadiene block copolymer and / or styrene-α-olefin copolymer, And it forms so that it may have the said specific film thickness.

Thereby, the said adhesive bond layer can acquire the initial adhesiveness of the said metal core material and the said polyolefin resin composition layer. Further, in a use environment of about -40 ° C to 80 ° C, it is possible to follow the expansion and contraction of the metal core material, and the adhesiveness between the metal core material and the polyolefin resin composition layer in a low temperature environment is reduced. Can be suppressed. Therefore, the variation in adhesive force can be reduced.
Moreover, the said adhesive bond layer can exhibit favorable adhesiveness with the said polyolefin resin composition layer.
That is, good adhesion can be obtained at the interface between the adhesive layer and the metal core material and at the interface between the adhesive layer and the polyolefin resin composition layer.

  Therefore, even if it is used for a long time, the adhesion between the metal core material and the polyolefin resin composition layer can be maintained. Even if the stress strain due to the molding process remains, it is possible to suppress the occurrence of interfacial peeling.

Thus, according to the present invention, it is possible to provide an automotive member that has excellent bonding strength, can reduce variations in adhesive strength, and does not cause interface peeling even when exposed to a use environment for a long time. it can.
Moreover, the said automobile member can have damage resistance with the said polyolefin resin composition layer, and can prevent the crack generation at the time of use resulting from the residual stress at the time of extrusion molding, etc.

  According to the second and third aspects of the invention, there is provided a method for producing an automobile member comprising a PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer, and a metal core material and a polyolefin resin composition, This is characterized in that a dispersion having styrene-α-olefin is interposed and bonded to each other. And the automobile member obtained by the said manufacturing method has the structure of the above-mentioned 1st invention.

  That is, according to the method of manufacturing the automobile member of the second and third inventions, the bonding strength is excellent, the variation in the adhesive force can be reduced, and the interfacial peeling is caused even when exposed to the use environment for a long time. An automobile member that does not occur can be obtained.

Explanatory drawing which shows the motor vehicle member in Example 1. FIG.

As described above, the automobile member of the first invention includes a metal core, an adhesive layer formed on the metal core, and a polyolefin resin laminated on the metal core via the adhesive layer. It consists of a composition layer.
As the metal core material, for example, a metal core material (shape material, strip, etc.) made of aluminum (pure aluminum and aluminum alloy), stainless steel or the like can be used.

  The adhesive layer is composed of 70 to 99% by mass of a polypropylene resin (modified PP resin) modified with maleic anhydride, 1 of a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. -30 mass% is mixed.

  When the content of the modified PP resin is less than 70% by mass, the initial adhesion between the metal core material and the polyolefin resin composition layer may not be sufficiently obtained. On the other hand, when the content of the modified PP resin exceeds 99% by mass, the adhesion between the metal core material and the polyolefin resin composition layer may be significantly reduced in a low temperature environment.

  When the total content of the styrene-isoprene-butadiene block copolymer and / or styrene-α-olefin copolymer is less than 1% by mass, the metal core material after the cooling test and the polyolefin resin composition There is a possibility that sufficient adhesion of the layer cannot be obtained. On the other hand, when the total content of the styrene-isoprene-butadiene block copolymer and / or the styrene-α-olefin copolymer exceeds 30% by mass, the initial adhesion between the metal core material and the polyolefin resin composition layer is as follows. There is a possibility that sufficient sex cannot be obtained.

Moreover, the thickness of the said adhesive bond layer is 0.1-10 micrometers.
When the thickness of the adhesive layer is less than 0.1 μm, the adhesive effect by the adhesive layer may not be sufficiently obtained. On the other hand, when the thickness of the adhesive layer exceeds 10 μm, cohesive failure occurs in the adhesive layer when the cooling and heating cycle is repeated, which may reduce the adhesive effect.
The thickness of the adhesive layer is more preferably 0.5 to 5 μm.

  Moreover, as said polyolefin resin composition layer in the said motor vehicle member, it can be set as the layer which consists of polyethylene, a polypropylene, etc., for example. In the present invention, the polyolefin resin composition layer may be TPO (thermoplastic polyolefin) or crystalline PP (crystalline polypropylene).

  As described above, the production method of the second invention uses, as a metal core, a dispersion comprising a PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin. After applying and drying, the metal core material is molded, and then the metal core material is coated with the polyolefin resin composition via the dispersion.

In this invention, after apply | coating the said dispersion, it is preferable to heat and dry beyond the melting | fusing point of the said modified PP resin, and to cool after that.
The dispersion can be applied by, for example, coating with a bar coater, roll coating, flow coating, spray coating, dip coating, or the like.

Moreover, as said shaping | molding process, processing methods, such as roll forming and press molding, are applicable, for example.
Moreover, it is preferable to perform a degreasing process before coat | covering the said polyolefin resin composition.
The polyolefin resin composition can be coated by, for example, a method in which the metal core material is introduced into a resin kneading extruder, a hot press method, or the like.

  As described above, the production method of the third invention uses, as a metal core, a dispersion comprising a PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin. After coating and drying, the metal core material is coated with the polyolefin resin composition via the dispersion, and then the metal core material is molded.

The dispersion can be applied by the same method as described above.
Moreover, after apply | coating the said dispersion, it is preferable to heat and dry beyond the melting | fusing point of the said modified PP resin, and to cool after that.

The polyolefin resin composition can be coated by a method such as hot pressing or lamination.
Further, as the molding process, a method similar to the above can be applied.

In the second and third inventions, the dispersion is a resin mixture comprising a polypropylene resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. The body is preferably dispersed in an organic solvent such as toluene, xylene, or solvesso.
Further, the resin mixture is composed of 70 to 99% by mass of a polypropylene resin (modified PP resin) modified with maleic anhydride, 1 of a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. It is preferably composed of ˜30% by mass.
The polyolefin resin composition is preferably TPO (thermoplastic polyolefin) or crystalline PP (crystalline polypropylene).

Example 1
In this example, an automobile member according to an embodiment of the present invention will be described.
In this example, eight types of automobile members (sample E1 to sample E8) were produced as examples, and five types of automobile members (sample C1 to sample C5) were produced as comparative examples.
The present invention is not limited only by these examples.

As shown in FIG. 1, the automobile member 1 (sample E <b> 1 to sample E <b> 8) includes a metal core 2, an adhesive layer 3 formed on the metal core 2, and a metal core via the adhesive layer 3. And a polyolefin resin composition layer 4 laminated on the material 2. The adhesive layer 3 is a mixture of 70 to 99% by mass of a polypropylene resin modified with maleic anhydride and 1 to 30% by mass of a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. Do it. The thickness of the adhesive layer 3 is 0.1 to 10 μm.
Samples C1 to C5 are prepared so that the composition or film thickness of the adhesive layer is outside the scope of the present invention.

In producing the automobile member 1 (sample E1 to sample E8 and sample C1 to sample C5), first, a metal made of an aluminum alloy plate (A5052P-H34, 0.5 mm thickness) subjected to phosphoric acid chromate treatment. A core material 2 was prepared.
In addition, resin dispersions (dispersion e1 to dispersion e6 and dispersion c1 to dispersion c3) constituting the adhesive layer 3 were prepared.
Moreover, the olefin type thermoplastic elastomer (EXCELINK1300, MFR170g / 10min, 230 degreeC, the product made from JSR) which comprises the polyolefin resin composition layer 4 was prepared.

Here, a manufacturing process of the resin dispersion (dispersion e1 to dispersion e6 and dispersion c1 to dispersion c3) will be described.
First, 15 parts of maleic anhydride and 400 parts of xylene were added to 100 parts of polypropylene resin (MFR 10 g / 10 min, 230 ° C.), and the mixture was stirred in a nitrogen gas atmosphere while heating to 130 ° C. A 1% xylene solution of benzoyl peroxide was added dropwise thereto over 2 hours. Furthermore, after stirring for 60 minutes at 130 ° C., the mixture was allowed to cool to room temperature. The obtained suspension was filtered, washed with methyl ethyl ketone, and a polypropylene resin (PP resin) modified with maleic anhydride was obtained.

And as a resin dispersion used for the sample E1, 10 parts of a styrene-isoprene-butadiene block copolymer was added to 90 parts of the modified PP resin to obtain a dispersion e1 dispersed in toluene.
Moreover, as a resin dispersion used for the sample E2, 30 parts of a styrene-isoprene-butadiene block copolymer was added to 70 parts of the modified PP resin to obtain a dispersion e2 dispersed in toluene.

Moreover, as a resin dispersion used for the sample E3, 1 part of a styrene-isoprene-butadiene block copolymer was added to 99 parts of the modified PP resin to obtain a dispersion e3 dispersed in toluene.
Moreover, as a resin dispersion used for the sample E4, 10 parts of a styrene-α-olefin copolymer was added to 90 parts of the modified PP resin to obtain a dispersion e4 dispersed in toluene.

Moreover, as a resin dispersion used for the sample E5, 1 part of a styrene-α-olefin copolymer was added to 99 parts of the modified PP resin to obtain a dispersion e5 dispersed in toluene.
Further, as a resin dispersion used for the sample E6, 15 parts of a styrene-isoprene-butadiene block copolymer and 15 parts of a styrene-α-olefin copolymer are added to 70 parts of the modified PP resin and dispersed in toluene. The body e6 was obtained.

Moreover, as a resin dispersion used for the sample C1, a dispersion c1 in which 100 parts of the modified PP resin was dispersed in toluene was obtained.
Moreover, as a resin dispersion used for the sample C2, 35 parts of a styrene-isoprene-butadiene block copolymer was added to 65 parts of the modified PP resin to obtain a dispersion c2 dispersed in toluene.
Moreover, as a resin dispersion used for the sample C3, 35 parts of a styrene-α-olefin copolymer was added to 65 parts of the modified PP resin to obtain a dispersion c3 dispersed in toluene.

  Then, each of the resin dispersions (dispersion e1 to dispersion e6 and dispersion c1 to dispersion c3) is applied to the metal core material 2 using a bar coater so as to have a dry film thickness of 1 μm. After that, it was heated so that the plate temperature reached temperature was 210 ° C. and then allowed to cool to form the adhesive layer 3.

The aluminum alloy plate having the adhesive layer thus obtained was molded into the shape of the metal core material 2 shown in FIG. 1 by roll forming.
Next, with respect to the obtained metal core material 2, using a single screw extruder equipped with a full flight type screw with a compression ratio of 3, an olefin-based thermoplastic elastomer (EXCELINK 1300, MFR 170 g / 10 min, 230 ° C., JSR ( Co., Ltd.) was coated by extrusion to a thickness of 3 mm to form a polyolefin resin composition layer 4 to obtain an automobile member 1 (samples E1 to E6 and samples C1 to C3).

  In addition, four types of automobile members (sample E7, sample E8, sample C4, and sample C5) in which the film thickness of the adhesive layer of the sample E1 was changed to the film thickness shown in Table 1 were produced. These were produced by the same method as Sample E1, except that the film thickness was changed.

Next, about the said automobile member 1 (sample E1-sample E8 and sample C1-sample C5), the tear test was done and adhesiveness evaluation was performed by observing a fracture | rupture form.
The tear test was carried out for each sample five times for each of the sample before the cooling test and the sample after the cooling test.
The cold test was performed by performing 2000 cycles of a cold test in which the test material was heated for 30 minutes at a temperature of 110 ° C. and then held for 30 minutes at a temperature of −40 ° C.

  In the tear test method, first, a cut is made between the metal core material (aluminum alloy plate) and the polyolefin resin composition layer using a knife at the end of the sample. Thereafter, the polyolefin resin composition layer was pulled by hand and peeled off from the metal core.

  And the fracture | rupture form was observed, and when the polyolefin resin composition layer remained and peeled in the metal core material surface in all 5 times, it judged that adhesiveness was favorable and evaluated as (circle). When the polyolefin resin composition layer did not remain on the surface of the metal core material even once out of 5 times, the adhesion was judged to be poor, and the evaluation was x. The results are shown in Table 1.

As is known from Table 1, all of Samples E1 to E8 have good adhesion between the metal core material before the cooling test and after the cooling test and the polyolefin resin composition layer, and have excellent adhesion. I understand that
Thus, according to this example, it can be seen that it is possible to obtain an automobile member that has excellent bonding strength, can reduce variations in adhesive strength, and does not cause interfacial peeling even when exposed to a use environment for a long time. .

  In addition, the adhesive layer of sample C1 is composed only of a polypropylene resin modified with maleic anhydride and does not contain any of a styrene-isoprene-butadiene block copolymer and a styrene-α-olefin copolymer. Although the adhesion before the test was excellent, the adhesion after the cooling test was not acceptable.

Moreover, since the content of the polypropylene resin modified with maleic anhydride is lower than the lower limit of the present invention and the content of the styrene-isoprene-butadiene block copolymer exceeds the upper limit of the present invention, the adhesive layer of sample C2 is, Both the adhesion before the cooling test and the adhesion after the cooling test were unacceptable.
In addition, the adhesive layer of Sample C3 has a content of the polypropylene resin modified with maleic anhydride below the lower limit of the present invention, and the content of the styrene-α olefin copolymer exceeds the upper limit of the present invention. Neither the previous adhesion nor the adhesion after the cooling test was rejected.

Moreover, since the film thickness of an adhesive layer is less than the minimum of this invention, the sample C4 cannot fully obtain the adhesive effect by an adhesive layer, and the adhesiveness before a thermal test and the adhesiveness after a thermal test All were unacceptable.
Moreover, since the film thickness of the adhesive layer exceeded the upper limit of this invention, the adhesive improvement effect by an adhesive layer was not fully acquired for sample C5, but the adhesiveness after a thermal test was inadequate.

  In this example, the metal core material 2 is molded before the polyolefin resin composition layer is formed, but may be molded after the polyolefin resin composition layer is formed. And if it has the structure of this invention, even if it is a case where the shaping | molding process is performed after polyolefin resin composition layer formation, the outstanding adhesiveness can be exhibited.

DESCRIPTION OF SYMBOLS 1 Automobile member 2 Metal core material 3 Adhesive layer 4 Polyolefin resin composition layer

Claims (4)

A metal core, an adhesive layer formed on the metal core, and a polyolefin resin composition layer laminated on the metal core via the adhesive layer,
The adhesive layer is prepared by mixing 70 to 99% by mass of a polypropylene resin modified with maleic anhydride and 1 to 30% by mass of a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin copolymer. And
The thickness of the said adhesive bond layer is 0.1-10 micrometers, The automotive member characterized by the above-mentioned.   The automobile member according to claim 1, wherein the polyolefin resin composition layer is made of TPO (thermoplastic polyolefin) or crystalline PP (crystalline polypropylene).   A dispersion containing PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin is applied to a metal core, dried, and then molded into the metal core. And then coating the polyolefin resin composition on the metal core through the dispersion.   A dispersion having a PP resin modified with maleic anhydride, a styrene-isoprene-butadiene block copolymer and / or a styrene-α-olefin is applied to a metal core, dried, and then dispersed in the metal core. A method for producing an automobile member, characterized in that a polyolefin resin composition is coated through a body and thereafter the metal core material is molded.

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