JPH10138268A - Skin material for mold press molding and car interior part using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a skin material for mold press molding integrated with a resin core material by a mold press suitable for recycling and excellent in the adhesiveness with the resin core material. SOLUTION: A skin material 30 for mold press molding integrated with a resin core material by press molds 40, 50 is constituted by integrally laminating an adhesive layer 32 composed of a low m.p. olefinic resin with an m.p. of 120-150 deg.C to the rear surface of a TPO sheet 31, for example, in a sheetlike, filmlike, weblike and liquid state. By this constitution, the good adhesiveness of the resin core material and the TPO sheet 31 is ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin material for mold press molding and an automobile interior part using the same.

[0002]

2. Description of the Related Art FIG. 4 is a cross-sectional view showing an automobile door trim 1 formed in a required shape by mold press molding. The automobile door trim 1 is formed into a desired curved surface shape, and has an appropriate shape retention. It is composed of a resin core material 2 provided and a skin material 3 integrally attached to the surface side of the resin core material 2 when the resin core material 2 is subjected to mold press molding.

As the resin core material 2, a polypropylene resin mixed with talc or the like is generally used because of its cost, moldability, rigidity and the like.
7 are conventionally implemented or proposed.

[0005] First, as shown in FIG. 5, a PVC sheet 3a (which has been subjected to a needle hole processing) and a wooly knitted cloth 3b as a skin material 3 are integrated with an adhesive 3c. Since the adhesiveness between 3a and the resin core material 2 (polypropylene resin) is poor, the wooly knitted cloth 3b is used as an adhesive medium.

FIG. 6 shows a laminated sheet in which an olefin-based thermoplastic elastomer (hereinafter, referred to as TPO) sheet 3d is lined with a foam layer 3e such as a polypropylene foam on the back surface, and FIG. , TP
This is a conventional example in which the O sheet 3d alone is used as the skin material 3.

[0006]

As described above, conventionally, at the time of mold press molding of a resin core material 2 made of a polypropylene resin, a skin material 3 for mold press molding which is press-integrated with the resin core material 2 is used. 5 to 7 are used. For example, when a laminated sheet in which a PVC sheet 3a and a wooly knitted cloth 3b are integrated with an adhesive 3c is used, the PVC sheet 3a is used.
The bonding strength between the woven fabric and the wooly knitted fabric 3b is unstable for each rod, and the PVC sheet 3a may peel off in some cases. In addition, the PVC sheet 3a cannot be recycled and there is a problem in terms of effective use of resources.

Next, in the case of a laminated sheet of the TPO sheet 3d and the foamed layer 3e, there is no problem with respect to adhesiveness and recycling, but the cost is high. Not suitable for

[0008] Finally, the TPO sheet 3d alone is applied to the skin material 3
When it is used as a single sheet, it is inexpensive in cost and advantageous in recycling, but when applied to the door trim 1, when the resin core material 2 is molded at the outer peripheral portion of the door trim 1, If the resin temperature is
The melting point of the TPO sheet 3d was lower than that of the TPO sheet 3d.

The present invention has been made in view of such circumstances, and provides a skin material for mold press molding which is inexpensive and has improved adhesion of a TPO sheet suitable for recycling. , TPO with excellent adhesion
It is an object of the present invention to provide an automobile interior part obtained by using a seat.

[0010]

In order to achieve the above object, the present invention relates to a mold press molding skin material which is integrally attached to a surface side of a resin core material formed into a required shape by mold press molding. The skin material for mold press molding is characterized in that it is constituted by a laminate in which an adhesive layer made of a low-melting olefin resin is adhered to the back surface of a TPO sheet.

The TPO sheet is a resin material having a rubber-like feel and does not require a compounding step or a vulcanizing step as in conventional rubber, and is formed in the same manner as a thermoplastic resin such as polyethylene or polypropylene. Processing is possible.

The TPO sheet has excellent heat resistance compared to other soft resins, has a low density, enables lighter products, has excellent flow characteristics at the time of molding, and has excellent chemical resistance,
Excellent weather resistance.

Here, as the TPO sheet, Mirastomer (trade name, manufactured by Mitsui Petrochemical Industries, Ltd.) and the like can be mentioned.

Next, as the adhesive layer made of a low-melting olefin resin, a low-melting polypropylene sheet having a melting point of 120 to 150 ° C. and a thickness of 0.2 to 0.4 mm, preferably 0.3 mm is good. Has a melting point of 12
A film-, web-, or liquid-type low-melting polyolefin hot melt at 0 to 150 ° C can be used. In particular, when a liquid hot melt is used, the back surface of the TPO sheet is integrated by spray coating. Become

Further, according to the present invention, after the above-mentioned skin material for mold press molding is set in a mold for mold press molding, a semi-molten resin as a material of a resin core material is distributed and supplied into the mold. By molding and pressing the resin core into the required shape by engaging and pressing the mold press mold, the TPO sheet is integrated with the surface of the resin core via the adhesive layer to produce interior parts for automobiles. It is characterized by doing.

Here, as interior parts for automobiles, it can be applied to door trims, rear corner trims and the like for automobiles, and as a resin core material, filler such as talc is mixed in consideration of cost, rigidity, moldability and the like. Polypropylene resins are preferred.

As is apparent from the above configuration, the skin material for mold press molding according to the present invention has an integrated adhesive layer made of a low-melting olefin resin on the back surface of the TPO sheet. When the skin material is set and the resin core material is subjected to mold press molding, the temperature of the semi-molten resin, which is the material of the resin core material, is 190 around the gate portion.
To 210 ° C., but 140 to 1 at the die end.
Although the temperature drops to 50 ° C., since the melting point of the adhesive layer made of the low-melting olefin resin is 120 to 150 ° C.,
The adhesive layer is melted, so that the TPO sheet can be satisfactorily adhered to the surface of the resin core even at the outer peripheral portion of the product.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a mold press molding skin material and an automobile interior part using the same according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a front view showing a door trim for an automobile manufactured using the surface material for mold press molding according to the present invention, FIG. 2 is a cross-sectional view showing the structure of the door trim for the automobile, and FIG. It is explanatory drawing which shows the mold press molding process of a door trim.

In FIG. 1 and FIG. 2, the automobile door trim 10 is generally constituted by a resin core material 20 and a skin material 30 integrally attached to the surface side of the resin core material 20.

More specifically, the resin core 20 is made of PP
PP mixed with resin or inorganic filler such as talc
A resin material such as a composite resin is distributed and supplied in a semi-molten state into a mold press molding die having a required curved surface shape, and is formed into a complicated curved surface shape by clamping the mold press molding die.

On the other hand, as the skin material 30, the resin core material 20 is used.
Are molded at the same time during mold press molding of
In the present embodiment, a laminated sheet having a two-layer structure in which an adhesive layer 32 made of a low-melting-point olefin-based resin is laminated on the back surface of the TPO sheet 31 is used.

The TPO sheet 31 has a thickness of 0.4 mm.
With a melting point of 160 to 180 ° C., a rubber-like surface feel, excellent heat resistance, very low density, excellent moldability, chemical resistance, weather resistance, and the like. Meilastomer (Mitsui Petrochemical Industry Co., Ltd.)
Made).

Further, the TPO sheet 31 may be subjected to a needle hole processing for the purpose of eliminating the air pool due to the shape of the door trim 10.

Next, the adhesive layer 32 provided on the back surface of the TPO sheet 31 has a thickness of 0.3 mm and a melting point of 12 mm.
A low melting point PP sheet of 0 to 150 ° C. is used.
Adhesive layer 32 composed of PO sheet 31 and low melting point PP sheet
Are integrated into a sheet by a frame laminator or the like.

Next, a process of forming the automobile door trim 10 using the skin material 30 will be described with reference to FIG.

First, the skin material 30 is set on the set pins 41 of the upper mold 40 for mold press molding with the TPO sheet 31 facing upward and the adhesive layer 32 facing downward.

When the setting of the skin material 30 is completed, the semi-molten resin M, which is the material of the resin core material 20, is placed on the mold surface of the lower mold 50 for mold press molding when the upper mold 40 is lowered by a predetermined stroke. Are distributed and supplied.

This molten resin M is distributed and supplied from the injection molding machine 60 connected to the lower mold 50 onto the mold surface of the lower mold 50 through the hot runner 51 and the gate 52 provided in the lower mold 50. You.

Thereafter, the upper mold 40 for mold press molding is lowered to the bottom dead center, and the upper and lower molds 40 and 50 are engaged with each other while maintaining a predetermined clearance, whereby the resin core material 20 is formed into a desired curved surface shape. At the same time, the skin material 30 is press-integrated on the surface side of the resin core material 20.

At this time, the resin heat temperature of the semi-molten resin M is
In the portion A near the gate 52, the temperature is 190 to 210 ° C.,
As the distance from the gate 52 increases, for example,
In the peripheral portion of the lower mold 50 indicated by B in the figure, the resin temperature of the semi-molten resin M decreases to 140 to 150 ° C.

However, the skin material 30 for mold press molding according to the present invention has a low melting point PP sheet 32 on the back surface of the TPO sheet.
Since the adhesive layer 32 is lined, the adhesive layer 32 is melted even in the portion B where the resin temperature decreases, and the resin core material 20 and the TPO sheet 31 are satisfactorily integrated through the adhesive layer 32. You.

As described above, the skin material 30 for mold press molding according to the present invention has an adhesive layer 32 made of a low-melting PP sheet integrally formed on the back surface of a TPO sheet 31 excellent in tactile sensation, heat resistance, moldability, and weather resistance. As described above, even in mold press molding of large parts, good adhesiveness can be ensured up to the end of the product as described above, and since all are unified with polyolefin resin,
It is suitable for recycling and inexpensive, and has high practical value.

Furthermore, in the above-described embodiment, a low melting point PP sheet is used as the adhesive layer 32. Instead, a hot melt made of a low melting point olefin resin having a melting point of 120 to 150 ° C. is used as the adhesive layer 32. The hot melt may be used in the form of a film, a web, or a liquid. In the case of a liquid, the hot melt can be applied to the back surface of the TPO sheet 31 by spray coating.

[0035]

As described above, the present invention has the following special functions and effects.

(1) The present invention comprises a laminated sheet material in which an adhesive layer made of a low-melting-point olefin resin is laminated on the back of a TPO sheet as a skin material for mold press molding. At the end of the mold where the resin temperature of the semi-molten resin decreases during mold press molding with the resin, the resin core material and the TPO sheet can be firmly bonded and integrated via the adhesive layer, and the skin material is peeled off This has the effect of maintaining good quality performance without fear of occurrence.

(2) The present invention has a structure in which an adhesive layer made of a low-melting-point olefin resin is integrated on the back surface of the TPO sheet as a skin material for mold press molding. Since it is inexpensive and unified with olefin-based resins, it is suitable for recycling and has the effect of greatly contributing to resource saving.

(3) The present invention provides an interior part for automobiles obtained by integrally molding a resin core material and a mold press molding skin material in which an adhesive layer made of a low melting point olefin resin is integrated on the back surface of a TPO sheet. Therefore, even if the resin temperature of the semi-molten resin, which is the material of the resin core material, is reduced by the mold shape of the mold press mold, good adhesion with the skin material can be achieved. There is also an effect that restrictions on the setting position of the gate are also eased, and the degree of freedom in designing a molded product and a molding die is greatly improved.

[Brief description of the drawings]

FIG. 1 is a front view showing an automobile door trim using a skin material for mold press molding according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is an explanatory view showing a mold press molding step of the automotive door trim shown in FIG. 1;

FIG. 4 is a sectional view showing a configuration of a conventional automobile door trim.

FIG. 5 is a cross-sectional view showing a conventional resin core material and skin material.

FIG. 6 is a cross-sectional view showing a conventional material of a resin core material and a skin material.

FIG. 7 is a cross-sectional view showing a conventional resin core material and skin material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Automotive door trim 20 Resin core material 30 Skin material for mold press molding 31 TPO sheet 32 Adhesive layer 40 Upper mold for mold press molding 50 Lower mold for mold press molding 52 Gate 60 Injection molding machine A Gate vicinity B Mold periphery

Claims (5)

[Claims] 1. A mold press molding skin material (30) integrally attached to a surface side of a resin core material (20) formed into a required shape by mold press molding, wherein the mold press molding skin material (30) is provided. ) Is a skin material for mold press molding, comprising a laminate in which an adhesive layer (32) made of a low-melting olefin-based resin is adhered to the back surface of a TPO sheet (31). 2. The skin material (3) for the mold press molding.
2. The skin material for mold press molding according to claim 1, wherein the adhesive layer (32) is a low-melting olefin resin sheet having a melting point of 120 to 150 [deg.] C. and a thickness of 0.2 to 0.4 mm. . 3. The mold press molding skin material (3)
The skin for mold press molding according to claim 1, wherein the adhesive layer (32) of (0) is a low melting point polyolefin resin hot melt having a melting point of 120 to 150 ° C formed in a film shape or a web shape. Wood. 4. The mold press molding skin material (3)
The adhesive layer (32) of (0) is made of a liquid hot melt made of a low melting point olefin resin having a melting point of 120 to 150 ° C. by TPO.
The skin material for mold press molding according to claim 1, wherein the back surface of the sheet (31) is integrated by spray coating. 5. A mold press molding die (40,5) comprising the mold press molding skin material (30) according to claim 1.
After setting in the mold, the semi-molten resin (M) as the material of the resin core material (20) is distributed and supplied into the mold, and the mold press molding dies (40, 50) are engaged and pressed. An automobile characterized in that the resin core material (20) is molded into a required shape by press molding, and the TPO sheet (31) is integrated with the surface of the resin core material (20) via an adhesive layer (32). Interior parts.