JPH07315142A - Synthetic resin side molding - Google Patents

Abstract

PURPOSE:To provide a side molding which can obviate the necessity of molding an extrusion molding article in which a metal insert is embedded, which can not form an edge in a side part, caused by cutting the extrusion molding article, and which can be directly used as a complete article without requiring end- molding of the extrusion molding article. CONSTITUTION:A synthetic side molding is adapted to be bonded to a door side panel or the like of an automobile through the intermediary, and is obtained by cutting an extrusion molding article 1 which is composed of a molding body layer 5, a thermal expansion and contraction restraining layer 7 which is embedded partly or entirely in the bottom part of the molding body layer 5 and which is simultaneously extruded with the molding body layer 5. The molding body layer 5 is made of a styrene group thermoplastic elastomer, and the thermal expansion and contraction restraining layer 7 is made of hard olefin group resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin side molding (hereinafter simply referred to as "side molding") which is attached to an automobile door side plate or the like via an adhesive layer. In particular, the invention relates to a side molding that can be manufactured with good productivity.

[0002]

2. Description of the Related Art Conventional side moldings are usually extruded using a thermoplastic synthetic resin material such as soft polyvinyl chloride or soft polypropylene, and cut into a predetermined length.
The terminal was injection molded.

Since the thermoplastic synthetic resin material has a high linear thermal expansion coefficient of 10 × 10 ^-5 / ° C. or more, it is particularly adhered to an automobile side plate made of an iron plate (the linear thermal expansion coefficient is 11 × 10 ^-6 / ° C.). When assembled via the agent layer, there is a risk of separation,
It is necessary to embed a metal insert and extrude. In the case where the insert is embedded and manufactured, it is necessary to hide the end surface of the metal insert because it appears on the end surface of the metal insert by cutting.

Further, the thermoplastic material usually has an edge formed on a ridge portion formed by cutting, and the hardness thereof usually exceeds about 60 ° in Shore A hardness. Therefore, the edge generated by this cutting needs to be rounded (R-attached), but the R-attachment work is troublesome and a finishing mark is likely to appear.

For these reasons, injection molding of the above-mentioned end portion is required.

Although the inventive property of the present invention is not directly affected, in JP-A-4-366635, a sandwich molding comprising a skin layer made of styrene type TPE and a core layer made of PP type resin is disclosed. Sidemall is disclosed.

[0007]

SUMMARY OF THE INVENTION In view of the above, the present invention eliminates the need for embedding a metal insert to form an extrusion-molded product, and has an edge at a ridge formed by cutting the extrusion-molded product. An object of the present invention is to provide a side molding that is not formed and can be used as a product as it is without extruding an extruded product after cutting.

[0008]

The synthetic resin side molding of the present invention is a styrene thermoplastic elastomer (hereinafter referred to as "styrene TPE") in the process of earnestly developing to solve the above problems. .) Found that almost no edge was generated by cutting, and found that if a heat expansion / contraction suppressing layer was formed of a hard olefin resin having a low linear expansion coefficient, a metal insert was not necessary. I thought about the side mall of the composition.

In a side molding that is manufactured by cutting an extrusion-molded product, which is attached to an automobile door side plate or the like via an adhesive layer, the extrusion-molded product includes a molding body layer and a molding body portion. Consisting of a heat expansion and contraction suppressing layer which is wholly or partially embedded on the bottom side and is extruded simultaneously, wherein the molding body layer is composed of a styrene-based thermoplastic elastomer,
The heat expansion / contraction suppressing layer is made of a hard olefin resin.

[0010]

EXAMPLES The present invention will now be described in detail based on examples.

(1) The side molding of the present invention is an extrusion-molded article 1 which is adhered to an automobile door side plate or the like via an adhesive layer.
Is cut and manufactured.

From the standpoint of workability, it is desirable that the adhesive layer is formed by attaching the double-sided tape 3 to the back surface of the side molding 1. The double-sided tape 3 is formed by forming an acrylic pressure-sensitive adhesive layer 3b on both sides of a base material sheet 3a such as foamed polyethylene and protecting it with a release paper 3c.

(2) The extruded product 1 comprises a molding body layer 5 and
A thermal expansion and contraction suppressing layer 7 which is wholly or partially embedded in the bottom side of the molding body layer 5 and is extruded simultaneously.

Here, the molding main body layer 5 is a hollow type from the viewpoint of weight reduction and shock absorption, but may be a solid type from the viewpoint of designability and the like. Also, the thermal expansion / contraction suppressing layer 7
From a design standpoint, the bottom side is exposed so that the pressing force on the double-sided tape acts uniformly, but it may be an entire buried structure covering the bottom side.

(3) In this embodiment, the molding body layer 5 is made of a styrene type TPE material. This styrene type T
In the extruded product molded with PE, the ridge (corner) generated by cutting has R (1 to 2 mmR), and the finishing work of the terminal edge is unnecessary, and by extension, the terminal molding is unnecessary.

Here, as the type of styrene-based TPE, polystyrene (PS) is used as the hard segment and polybutadiene, polyisoprene, and polyolefin are used as the soft segments, respectively, SBS, SIS, SE.
Any of the BSs can be used. In particular, SEBS having no double bond is desirable because it is excellent in heat aging resistance, weather resistance, abrasion resistance, and the like, and is excellent in compatibility with the heat expansion / contraction suppressing layer made of a hard olefin resin.

The hardness of the styrene-based TPE material is not particularly limited, but it is desirable that the Shore A is in the range of 50 to 60 ° from the viewpoints of the ease of forming with R and the shape retention of the material.

(5) The heat expansion / contraction suppressing layer 7 is made of a hard olefin resin. This hard olefin-based resin is a non-polar polymer material similar to the styrene-based TPE that is the material for forming the molding main body layer 5, and therefore, when the molding main body layer 5 and the thermal expansion / contraction suppressing layer 7 are co-extruded, the interface Satisfactorily melts together, and a strong bonding force is obtained between the layers 5 and 7. Therefore, even without using a metal insert, the thermal expansion / contraction suppressing layer 7 imparts a necessary thermal expansion / contraction suppressing effect to the side molding adhered to the vehicle body via the adhesive layer.

It is desirable that the hard olefin resin has a coefficient of thermal expansion as small as possible, and a coefficient of linear thermal expansion of 5 × 10 5.
It is desirable to use the one in which the inorganic fibers are filled so that the temperature is ^-5 / ° C or less.

Here, as the hard olefin resin,
Examples thereof include polypropylene and polyethylene. As the inorganic fibers, glass fibers, whiskers (whisker crystals) and the like can be preferably used. The blending amount of the inorganic fibers is 10 to 200 parts by weight with respect to 100 parts by weight of the resin content.

The thickness of the thermal expansion and contraction suppressing layer 7 usually depends on the thickness of the main molding layer, but is usually 1 to 3 mm. If it is too thin, it will be difficult to exert the effect of suppressing thermal expansion and contraction, and if it is too thick, the soft feeling and cushioning function of the side molding will be hindered
Also, when cut, the upper edge of the expansion-contraction suppressing layer 7 relatively shifts to the upper side, which is not desirable.

[0022]

As described above, the synthetic resin side molding according to the present invention has the following structure because the molding main body layer is made of a styrene-based TPE material and the thermal expansion / contraction suppressing layer is made of a hard olefin-based resin. Has various functions and effects.

(1) Since the molding body layer is made of a styrene-based TPE material, the ridges formed by cutting the extruded product have R, so that edge finishing for rounding and terminal molding are unnecessary. Become.

(2) Since a nonpolar hard olefin resin similar to the styrene-based TPE forming the molding body layer is used as the thermal expansion / contraction suppressing layer, when both layers are coextruded,
Good phase fusion is achieved, and a strong bonding force is obtained between both layers. Then, the heat expansion / contraction suppressing layer imparts a necessary heat expansion / contraction suppressing effect to the side molding adhered to the vehicle body via the adhesive layer. Further, since the cut end surface of the heat expansion and contraction suppressing layer is not a metal but a synthetic resin and is flush with the cut end surface of the molding body layer, it is not necessary to conceal it by terminal molding.

Therefore, it is not necessary to embed a metal insert to form an extrusion-molded product, and the extruded product after cutting need not be end-molded and can be used as a product as it is.

The side molding of the cross section shown in FIG.
The molding main body layer 5 and the heat expansion / contraction suppressing layer 7 are extrusion-molded (molding temperature: 185 ° C.) using styrene-based TPE and hard olefin-based resin having the following specifications, respectively, and cut at an inclination angle (relative to the bottom surface) of 60 °. As a result, the ridge portion generated by cutting had 1.5R.

Styrenic TPE: SEB manufactured by Mitsubishi Petrochemical Co., Ltd.
S, hardness: Shore A 55 ° hard olefin resin ... Glass fiber-filled PP manufactured by Dai Nippon ink Co., Ltd. Filling amount: 15 wt%, coefficient of linear thermal expansion: 3 × 10 ⁻⁵

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a side molding showing an example of the present invention.

[Explanation of symbols]

 1 Extruded product 3 Adhesive layer 5 Mall body layer 7 Thermal expansion / contraction layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshio Yamazaki Yoshio Yamazaki, 1 Ochiai, Ochiai, Kasuga-cho, Nishikasugai-gun, Aichi Prefecture, Toyoda Gosei Co., Ltd. Toyoda Gosei Co., Ltd.

Claims (2)

[Claims] 1. A side molding that is produced by cutting an extruded product, which is attached to a door side plate of an automobile via an adhesive layer, wherein the extruded product comprises a molding body layer and a molding body. A heat expansion and contraction suppressing layer that is wholly or partially embedded in the bottom of the layer and is extruded simultaneously, the molding body layer is made of a styrene-based thermoplastic elastomer, and the heat expansion and contraction suppressing layer is made of a hard olefin resin. A synthetic resin side molding characterized by this. 2. The mold body layer according to claim 1, wherein the molding body layer is made of a styrene-based thermoplastic elastomer having a hardness of Shore A of 50 to 60 °, and the thermal expansion and contraction suppressing layer has a coefficient of linear thermal expansion of 5 × 10 ⁻⁵ / A synthetic resin side molding, characterized in that it is made of a hard olefin-based resin filled with inorganic fibers so that the temperature is not higher than ° C.