JP2002087178A - Weather strip for car and method of manufacturing the weather strip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a weather strip capable of providing a visually soft feeling in addition to a manually soft touch feeling. SOLUTION: This weather strip 10 comprises a mounting base part 12 installed on a body side member and formed of an EPDM solid rubber, a cushion layer 18 stacked on the mounting base part 12 and formed of an EPDM sponge rubber, a skin layer 20 stacked on the cushion layer 18 and formed by foaming an olefin-based thermoplastic elastomer, and an olefin-based adhesive layer 22 for adhering the cushion layer 18 to the skin layer 20. Since the skin layer 20 is a foamed layer, the layer provides a visually soft feeling. The cushion layer 18 is provided on almost all the areas of the portions having the skin layer 20 installed thereon, and provides a tactily soft feeling given when the skin layer 20 is touched manually.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weather strip for automobiles, which is made of solid rubber, has a cushion layer, and whose surface is decorated, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a technique disclosed in Japanese Patent Application Laid-Open No. Hei 6-16094 is known as this kind of weather strip for automobiles. That is, this weather strip is an ethylene-propylene-diene copolymer (E
PDM), a rubber base made of solid rubber of PDM), a decorative skin material for covering the rubber base in a region of the rubber base exposed in the vehicle interior, and an EPDM between the decorative skin material and the base.
And a cushion layer made of sponge rubber.
The cushion layer collapses following an external force from the decorative skin material side and returns to its original shape by release of the external force, thereby giving a soft touch feeling.

[0003]

However, the decorative skin material mounted on the surface of the cushion layer is a woven fabric made of a polyester fiber which is previously colored, or a resin sheet material such as PVC. A soft feeling in appearance cannot be obtained from itself. Moreover, even if it is polyester, PV
C, since there is no adhesiveness to the EPDM rubber substrate, a special two-layer adhesive film having adhesiveness is required for the adhesion between the skin material and the EPDM rubber substrate. Has contributed to the rise. Further, in this weather strip, the cross section U
The cushion layer is provided only between the top part of the rubber base of the letter shape and the skin material, and the outer lip protruding inside the car is
Since it is formed only of solid rubber, a soft feeling at this portion cannot be sufficiently obtained. For this reason, there has been a problem that sufficient softness and luxury cannot be obtained as interior materials for automobiles.

The present invention solves the above-mentioned problems of the prior art, and provides a soft feeling in appearance in addition to the tactile sensation at a portion where the skin layer is provided and over the entire area, and is relatively inexpensive. It is an object of the present invention to provide a weather strip for an automobile and a manufacturing method thereof.

[0005]

Means for Solving the Problems and Action / Effect Thereof A first invention for solving the above-mentioned problems is directed to a weather strip for an automobile, which is mounted on a vehicle body side member and is made of EPR solid rubber. A cushion layer formed of EPR sponge rubber laminated on the base and the mounting base; a skin layer laminated on the cushion layer and formed by foaming an olefin-based thermoplastic elastomer; a cushion layer and a skin layer And an olefin-based adhesive layer for adhering the above.

A weather strip for an automobile according to the first invention is attached to a vehicle body-side member by an attachment base made of EPR solid rubber. A skin layer is mounted on the mounting base via a cushion layer and an adhesive layer. Since the skin layer is a foamed layer, it can give a soft feeling in appearance. Further, the cushion layer disposed below the skin layer is formed of sponge rubber of EPR, and is provided substantially over the entire area where the skin layer is provided, so that a soft feeling can be given on the tactile sensation. Further, since the mounting base, the cushion layer, the adhesive layer, and the skin layer are all formed of an olefin-based material, they are firmly thermally welded to each other and do not peel off.

A second aspect of the present invention is a method of manufacturing a weather strip for an automobile according to the first aspect of the present invention, in which an EPR is extruded to form an extruded body serving as a mounting base and a cushion layer; A step of vulcanizing the molded body, and while extruding a foamable olefin-based thermoplastic elastomer to form a skin layer, the adhesive sheet made of an olefin-based material for forming an adhesive layer is formed of the above-mentioned skin sheet and cushion layer. Extruding the skin sheet so as to be interposed between them, and setting the temperatures of the skin sheet, the adhesive sheet, and the extruded body so as to maintain the foamed cells of the skin sheet, and superimposing the three members. A step of heat-welding the skin sheet to the surface of the cushion layer via the adhesive sheet by pressing with a roller,
A method for manufacturing a weather strip, comprising: It is characterized by having.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of the present invention will be described below.

FIG. 1 is an external view showing an automobile body BD to which a weather strip 10 is attached. Car body B
A weather strip 10 is attached to the periphery of the door opening D of D. FIG. 2 is a sectional view showing the weather strip (weather strip door opening trim) 10.

In FIG. 2, the weather strip 10 is
EPD that is attached to the vehicle body side member and is a kind of EPR
M mounting base 12 made of solid rubber, mounting base 1
2, a cushion layer 18 formed of EPDM sponge rubber, a skin layer 20 laminated on the cushion layer 18 and formed by foaming an olefin-based thermoplastic elastomer, a cushion layer 18 and a skin layer An olefin-based adhesive layer 22 for adhering the mounting base 12, a hollow seal portion 24 projecting from one side surface (outside of the vehicle) of the mounting base 12, and a hollow sealing portion 24 projecting from the other side surface (inside of the vehicle) of the mounting base 12. Outer lip 18a.

The mounting base 12 has a rubber base 13 made of solid rubber having a U-shaped cross section and a support lip 14 protruding inside the rubber base 13. Rubber base 13
Inside, an insert member 16 for retaining the U-shaped shape is embedded.

The cushion layer 18 has an outer lip 18a protruding so as to be in pressure contact with the interior member W on the vehicle interior side.
, That is, substantially the entire area of the rubber base 13 that is to be exposed in the vehicle interior. The cushion layer 18 is made of a highly foamed sponge rubber of EPDM and has a thickness of 1 to 8 mm, and is formed so as to collapse following an external force from the skin layer 20 and to return to its original shape by releasing the external force. The rubber base 13 and the cushion layer 18 are integrally extruded by simultaneous extrusion, and are simultaneously vulcanized and joined.

FIG. 3 shows the cushion layer 18 and the skin layer 20.
FIG. 2 is an explanatory diagram showing an enlarged view of the laminated structure of FIG. Skin layer 20
Are bonded to the cushion layer 18 via an adhesive layer 22 for heat welding. The skin layer 20 is formed in a sheet shape by foaming an olefin-based thermoplastic elastomer, and has a thickness of 0.3 to 0.7 mm. In addition,
The skin layer 20 is colored in advance with a color that matches the color tone in the vehicle cabin by adding a pigment, a pigment, a paint, or the like.

The adhesive layer 22 is a film-like layer interposed between the skin layer 20 and the cushion layer 18 and heat-sealed to each other, and is formed of polyethylene (PE) having a melting point of 110 to 140 °. ing. The thickness of the adhesive layer 22 is about 0.1 mm, and performs an adhesive action.
After vulcanizing the rubber base 13 and the cushion layer 18, a soft feeling is lost in consideration of an action of blocking the remaining sulfur vulcanizing chemicals and the like bleeding to the surface from migrating to the skin layer 20. Not set to thickness. The adhesive layer 22 also plays a role of blocking the black color of the rubber of the cushion layer 18 of the sponge rubber and brightening the color of the skin layer 20 when a film of a bright color such as white is used.

The hollow seal portion 24 is hollowly formed of sponge rubber from one side surface (outside of the vehicle) of the rubber base 13,
It is formed so as to perform a sealing action with the door side member.

Next, a method of manufacturing the weather strip 10 will be described with reference to a schematic view of a production line shown in FIG. As shown in FIG. 4, first, extrusion molding of the rubber base 13 and the like is performed. For the extrusion molding, a crosshead type extruder 30 is used. That is, the extruder 30 includes a solid rubber extruder 32 including a cylinder filled with an unvulcanized EPDM solid rubber material and a screw, a cylinder filled with an unvulcanized EPDM sponge rubber material, and a screw. A sponge rubber extruder 34, 36 having
A core material feeder 40 accommodating a core material 16A serving as the insert member 16, from which a solid rubber material, a sponge rubber material and a core material 16A are supplied to one extrusion head and simultaneously extruded, so-called co-extrusion is performed; An extruded body 12A is formed. Here, EPDM refers to an ethylene-α-olefin-non-conjugated diene copolymer rubber represented by an ethylene-propylene-diene ternary rubber.
EPDM solid rubber and sponge rubber materials usually include reinforcing fillers (carbon black), plasticizers,
Auxiliary materials such as lubricants and vulcanizing agents are blended. The sponge rubber contains a foaming agent in addition to the above.

In the extruded body 12A, the portion where the solid rubber material is extruded from the solid rubber extruder 32 becomes the rubber base 13, the portion where the sponge rubber material is extruded from the sponge rubber extruder 34 becomes the cushion layer 18,
The portion where the sponge rubber material is extruded from another sponge rubber extruder 36 becomes the hollow seal portion 24. In addition, the cushion layer 18 and the hollow seal portion 24 may be connected to each other, and the same sponge rubber material may be extruded so that one sponge rubber extruder may be used. Further, a plate made of stainless steel or mild steel can be used for the core 16A.

Next, a vulcanization step is performed. The vulcanization step is a step of vulcanizing the rubber by passing the extruded body 12A of unvulcanized rubber through a microwave heating device (UHF) 44 and a hot air vulcanizing device (HAV) 46. In this step, a temperature of 180 ° C. to 24 ° C. suitable for vulcanizing EPDM is used.
Perform at 0 ° C. The vulcanization time (passing time of the heating device and the vulcanization device) is about 3 to 10 minutes. The vulcanized extrudate 12A is passed through a cooling
Allow to cool to ° C. In this vulcanization step, EP
The foaming agent in the DM sponge rubber foams, and a predetermined sponge rubber is obtained.

Subsequently, a step of laminating the skin layer 20 is performed. That is, in this step, a material obtained by adding a foaming agent to a thermoplastic elastomer is extruded from the extruder 50 to form the skin sheet 20A, and at the same time, an adhesive sheet 22A made of PE is formed on one back of the skin sheet 20A by one extrusion head. And extrude it into a laminate. As the thermoplastic elastomer, polypropylene (PP) 2 is added to 80 parts by weight of EPDM.
What mixed 0 weight part can be used. In addition,
In the cylinder of the extruder 50, the thermoplastic elastomer is
It is heated to 00 to 260 ° C. to be in a molten state, and at this time, the dispersed foaming agent also melts and foaming starts,
It is not bubbled by the pressure in the cylinder,
When it is extruded from the extrusion head and becomes under atmospheric pressure,
The foamed skin sheet 20A is formed by swelling and bubbles.

The laminated sheet of the skin sheet 20A and the adhesive sheet 22A is guided to the pressure roller 52, and is pressed by the pressure roller 52 onto the extruded body 12A. At this time, the temperature of the skin sheet 20A decreases before reaching the pressure roller 52, and at the time of the pressure roller 52, the temperature is lower than the temperature at which the thermoplastic elastomer is thermally deformed.
Since the temperature is about 140 ° C., that is, a low temperature at which the bubbles are not crushed, the bubbles are not crushed even when pressed by the pressure roller 52 and are restored to maintain a foamed state. On the other hand, since the adhesive layer 22 is made of PE having a melting point of 110 to 140 ° C., the adhesive layer 22 is in a sufficiently softened state even when guided to the pressure roller 52, and is easily thermally welded to the cushion layer 18. Can be. Therefore, the laminated sheet can be thermally welded to the cushion layer 18 without increasing the surface temperature of the skin layer 20 and without crushing the foamed bubbles. After the pressure bonding step by the pressure roller 52, the skin layer 20 is bonded to the cushion layer 18 by heat welding via the adhesive sheet 22A.

Subsequently, the product obtained by bonding the skin layer 20 to the extruded product 12A after vulcanization is cooled by a cooler (not shown), and further bent by a processing machine into a U-shaped cross section to have a predetermined length. Through a process such as cutting, the weather strip 10 of FIG. 1 is completed.

As described above, according to weather strip 10 of the present embodiment, skin layer 20 is a foamed layer in a range exposed in the vehicle cabin, so that a soft feeling can be given in appearance. it can. In addition, skin layer 2
The cushion layer 18 is provided in substantially the entire area below the 0 layer, and this cushion layer 18 can give a soft feeling in tactile sensation. Thus, the weatherstrip 10 can give a soft feeling to both the appearance and the touch.

The mounting base 12, the cushion layer 18,
Since the adhesive layer 22 and the skin layer 20 are all formed of an olefin-based material, they are firmly thermally welded to each other and do not peel off. In addition, since the adhesive layer 22 is formed of PE having a low melting point, even when the temperature is reduced to a temperature at which foaming bubbles of the skin layer 20 are not crushed at the time of roller pressing, heat welding of PE to the cushion layer 18 can be performed firmly. it can. Furthermore, since all are formed from olefin-based materials, there is no need to use a special two-layer adhesive film described in the prior art, and the manufacturing cost can be reduced.

Further, since the skin layer 20 can be easily changed according to the color tone of the interior member W on the vehicle interior side, matching with the color tone in the vehicle interior is easy.

According to the weather strip 10, since the bonding between the cushion layer 18 and the skin layer 20 is performed on a series of production lines after extruding the extruded body 12A, the productivity is excellent. ing.

The present invention is not limited to the above-described embodiment, but can be embodied in various modes without departing from the gist thereof. For example, the following modifications are possible.

(1) FIG. 5 is a sectional view showing a weather strip 100 according to another embodiment. In the weather strip 100, an outer layer portion 18 b, which is a part outside the insert member 16 of the mounting base 112 having a U-shaped cross section, is formed of sponge rubber, and this is included in the cushion layer 118. In this case, a single sponge rubber extruder can be manufactured by continuously and integrally molding the hollow seal portion 24 and the outer lip 18a. Further, the thickness of the sponge rubber can be made thicker than that of FIG. 2, and a softer feeling can be obtained.

(2) In the step of manufacturing the weather strip 10, the skin layer 20 is adhered to the extruded body 12A by the pressure roller 52, but is not limited to this. Is also good.

[Brief description of the drawings]

FIG. 1 is an external view showing an automobile body BD to which a weather strip 10 is attached.

FIG. 2 is a sectional view showing the weather strip 10.

FIG. 3 is an enlarged explanatory view showing a laminated structure of a cushion layer 18 and a skin layer 20.

FIG. 4 is a schematic diagram showing a production line for the weather strip 10.

FIG. 5 shows a weather strip 100 according to another embodiment.
FIG.

[Explanation of symbols]

 10, 100 ... weather strip 12 ... mounting base 12A ... extruded body 13 ... rubber base 14 ... support lip 16 ... insert member 16A ... core material 18 ... cushion layer 18a ... outer lip 20 ... skin layer 20A ... skin sheet 22 ... Adhesive layer 22A Adhesive sheet 24 Hollow seal 30 Extruder 32 Solid rubber extruder 34, 36 Sponge rubber extruder 40 Core feeder 44 Microwave heating device 46 Hot air vulcanizing device 48 Cooling Device 50: Extruder 52: Crimping roller BD: Automobile body D: Door opening W: Interior member

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D024 AA02 AB06 AB19 AB24 AB34 AB36 AB57 4F213 AA09 AA45 AB02 AG03 AH23 WA06 WA15 WA43 WA53 WA87 WB02

Claims (2)

[Claims] 1. A weather strip for an automobile, wherein the mounting strip is attached to a vehicle body-side member and is made of a solid rubber of ethylene / propylene rubber (hereinafter, EPR); A cushion layer, a skin layer laminated on the cushion layer and formed by foaming an olefin-based thermoplastic elastomer, and an olefin-based adhesive layer for bonding the cushion layer and the skin layer. Characteristic automotive weather strip. 2. A method for manufacturing a weather strip for an automobile according to claim 1, wherein an EPR is extruded to form an extruded body serving as a mounting base and a cushion layer, and the extruded body is vulcanized. Process, while extruding a foamable olefin-based thermoplastic elastomer to form a skin layer, an adhesive sheet made of an olefin-based material for forming an adhesive layer is interposed between the skin sheet and the cushion layer. And the temperature of the skin sheet, the adhesive sheet and the extruded body are set so as to maintain the foamed bubbles of the skin sheet, and the above three members are pressure-bonded with an overlapping roller. Heat-welding the skin sheet to the surface of the cushion layer via an adhesive sheet. Method of manufacturing-up.