JPH04197845A - Insert mold body and manufacture thereof - Google Patents

Abstract

PURPOSE:To form into a complicated shape by a later machining in an insert mold body wherein a metallic insert member is embedded in an EPDM made rubber base body by bonding the insert member to the rubber base body via a laminated film composed of a specific material. CONSTITUTION:In an insert mold body provided with an EPDM made rubber base body 5 and a metallic insert member 3 embedded in this rubber base body 5, the insert member 3 is thermally welded in the rubber base body 5 via a laminated film 7A. The laminated film 7A is constituted of a first film 11A arranged on the side of the rubber base body 5 and a second film 13A arranged on the side of the insert member 3. For a material of the first film 11A an olefin resin having a polar functional group is adapted while for a material of the second film 13A a thermoplastic resin having a polarity, for example, a copolymerized polyester resin is adapted.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an insert molded article in which a metallic insert member is embedded in a rubber base made of EPDM, and a method for manufacturing the same. [Prior art and its problems] Conventionally, rubber made of EPDM has been used in many parts of automobiles where weather resistance, ozone resistance, heat resistance, etc. are important. There are weather strips that are attached around door openings, etc. In such weatherstrips, insert molding is performed in which a rubber base is extruded simultaneously with a metal insert member, and then vulcanization and mechanical processing such as bending are performed to produce a product. However, when molding weatherstrips with complex shapes, if the adhesion between the rubber base and the insert member is not good, the rubber base and the insert member may separate during bending. There was a problem in that it was difficult to bend it into a desired shape. The present invention aims to solve the above-mentioned problems of the conventional technology, and it is possible to integrally embed a metal insert member in a rubber base made of EPDM, and it can be formed into a complicated shape by later machining. The object of the present invention is to provide an insert molded body that can be used as an insert molded body and a method for manufacturing the same.

[Means to solve the problem]

Among the present inventions made to solve the above problems, the invention according to claim 1 provides an insert molded body comprising a rubber base made of EPDM and a metallic insert member embedded in the rubber base, An insert member is thermally welded to the rubber base via a laminated film, and the laminated film includes a first film made of an olefin resin having a polar functional group and disposed on the rubber base side, and the insert. It is characterized in that it uses a laminated film with a second film disposed on the member side and made of a polar thermoplastic resin. Further, the invention of claim 2 provides that the rubber base made of EPDM includes:
In a method for producing an insert molded body in which a metallic insert member is embedded, a rubber base and an insert member laminated with a laminated film are integrally extruded, and the extruded rubber base is vulcanized at a predetermined temperature. At the same time, the insert member is thermally welded to the rubber base through a laminated film, and the laminated film includes a first film made of an olefin resin having a polar functional group and disposed on the rubber base side, and the insert member. It is characterized in that it uses a laminate with a second film disposed on the member side and made of a polar thermoplastic resin. Here, EPDM refers to ethylene-α-olefin-nonconjugated genocopolymer rubber, of which ethylene propylene diene ternary rubber is a typical example. Moreover, a laminated film is a film in which a first film and a second film are laminated. The first film is made by introducing a polar functional group into a non-polar olefin resin. In other words, the first film has adhesiveness to EPDM as an inherent property of olefin-based resins, and also has adhesiveness to resins such as polyethylene and nylon by introducing polar functional groups. It was added. Examples of polar functional groups that impart such properties include carboxyl groups, hydroxyl groups, amine groups, halogen groups, and acrylic groups. Further, the second film is made of a polar resin,
It is a thermoplastic resin that melts when heated. That is, the second film has the property of adhering to both the first film and the metal member. Further, the insert member is a metal member that has the property of adhering to the second film and has strength as a core material, and may be made of, for example, iron, stainless steel, copper, aluminum, or the like. [Function] The rubber substrate of the present invention uses EPDM, which has excellent heat resistance, weather resistance, and ozone resistance. EPDM has poor adhesion to metallic materials. In order to adhere a metallic insert member to an EPDM rubber substrate having such properties, a laminated film is used in the present invention. The laminated film includes a first film made of an olefin resin having a polar functional group,
A second film made of polar thermoplastic and a second film are laminated together. Since the first film has a polar functional group introduced into the non-polar olefin resin, it is easily laminated with the second film which is a polar thermoplastic resin such as polyester. Using such a laminated film, the second layer of the laminated film
The film is placed on the insert member side and extruded at the same time as the rubber base, and then the rubber base is vulcanized. Due to the heat generated during vulcanization, the first film is welded to EPDM, which is an olefin rubber, because it is compatible with the EPDM, and the second film is firmly welded to the insert member because it has polarity.

【Example】

An embodiment of the present invention will be described below. (1) Insert molded body First, in explaining the examples, the basic structure of the insert molded body shown in FIG. 2 and its manufacturing method will be explained. In FIG. 2, the insert molded body 2 has an insert member 3 embedded in a rubber base 5 made of EPDM. The insert member 3 is adhered to the rubber base 5 via the laminated film 7A. The laminated film 7A is composed of a first film IIA disposed on the rubber base 5 side and a second film 13A disposed on the insert member 3 side. Here, EPDM is produced by adding a small amount of a non-conjugated diene such as tylidenobornene, dicyclopentadiene, or 1°4-hexadiene as a third component to ethylene or α-olefin (e.g. propylene). EPDM is copolymerized to introduce double bonds into the side chains, making it sulfur vulcanizable. EPDM usually contains reinforcing fillers (carbon black or white fillers), plasticizers, lubricants, and vulcanization. Auxiliary materials such as sulfur-based chemicals are blended.The material of the first film IIA is an olefin resin having a polar functional group.For example, Atmer (manufactured by Mitsui Petrochemical Industries, Ltd.: trade name), Bond First (Sumitomo Chemical Co., Ltd.: trade name) and Modic (Mitsubishi Yuka Co., Ltd.: trade name) can be used. The material of the second film 13A is a copolymerized polyester resin. For example, Chemit R- 248 (manufactured by Toshi Co., Ltd.: trade name) can be used.Furthermore, the insert member 3 is a core material that has adhesive properties with the second film 13A, and for example, a metal material such as iron can be used. Next, a method for manufacturing the double insert molded body 2 will be explained. The insert molded body 2 is manufactured by the production line shown in FIG. 1, but before explaining the continuous process by the production line, the process of forming the laminated film 7A will be explained. As a method for forming such a laminated film 7A,
Well-known extrusion lamination methods, dry lamination methods, wet lamination methods, hot melt lamination methods, two-layer inflation methods, etc. can be used. Among them, the extrusion lamination method, which is the most suitable method for producing the laminated film 7A, is to produce the first film ILA from a T-shaped die installed at the tip of an extruder.
By co-extruding the respective molten resin materials of the second film 13A and the second film 13A, a wide film is laminated and formed. Furthermore, the dry lamination method is a method in which separately formed films are bonded together using an adhesive in a separate process. Next, the molding process shown in FIG. 1 will be explained. First, the rubber base 5 is extruded together with the insert member 3. That is, the EPDM material 21 is used as the solid rubber material of the rubber base 5, and the laminated film 7
By using the insert member 3 to which A has been heat-welded in advance and extruding it with an extruder 23, the rubber base 5 is formed.
Manufacture. Next, vulcanization treatment is performed. This step is carried out by passing the extruded rubber substrate 5 through a vulcanization tank 25. The temperature for vulcanization is 18, which is suitable for vulcanizing EPDM.
It is carried out at 0°C to 240°C. In this step, the laminated film 7A adhered to the insert member 3 is welded to the rubber base 5 by heat generated during vulcanization of the rubber base 5. In other words, the insert member 3 is adhesively fixed within the rubber base 5. After going through the steps described above and cooling, the product is completed by bending or other processing into a desired shape. In the above embodiment, in order to adhere the insert member 3 into the rubber base 5 made of EPDM, the first film IIA, which is a non-polar olefin resin with polar functional groups introduced therein, and the polar second film 13A are used. A laminated film 7A is used in which the following are laminated. That is, the laminated film 7A is placed between the rubber base 5 and the insert member 3 such that the first film 11A of the laminated film 7A is placed on the rubber base 5 side and the second film 13A is placed on the insert member 3 side. These are interposed and welded by heat during vulcanization of the rubber base 5. This results in
The first film 11A is EP, which is an olefin rubber.
Since it is compatible with DM, it adheres to the rubber base 5, and the second
Since the film 13A has polarity, it firmly adheres to the insert member 3. As a result, the insert member 3 is firmly adhered to the rubber base 5, and the rubber base 5 and the insert member 3 do not separate even during complex processing and molding, thereby obtaining an insert molded product 2 with high workability. be able to. According to the embodiment described above, the following effects can be obtained. (2) Since the rubber base 5 and the insert member 3 are bonded together using heat during vulcanization, productivity is excellent. ■ The heat during vulcanization is used as the energy for thermal welding in the adhesive process, which also contributes to energy savings. ■ Uses heat welding, so no adhesive is required.
Therefore, cost reduction can also be achieved. (2) Weatherstrip Next, an example of a weatherstrip door opening trim (hereinafter referred to as weatherstrip) will be described. As shown in FIG. 3, the weather strip 31 is attached to the periphery of a door opening 35 of an automobile body 33. As shown in FIG. FIG. 4 shows a cross section of the weather strip 31. As shown in Figure 4, the flange of the door opening (not shown)
The rubber base 37 is made of solid rubber and has a U-shaped cross section.
is attached in a press-contact state with a lip 39. An insert member 41 is embedded within the rubber base 37 and is bonded to the rubber base 37 via a laminated film 40 . Furthermore, a decorative insert member 43 is adhered to the surface of the rubber base 37 facing toward the passenger compartment via a laminated film 42 . A hollow seal portion 45 made of sponge rubber for sealing is integrally formed on the side of the rubber base 37. Next, a method for manufacturing a weather strip will be explained with reference to FIG. First, extrusion molding was performed. A crosshead type extruder 51 was used for extrusion molding. That is, so-called co-extrusion was performed in which the EPDM material and sponge rubber material filled in the cylinders 53 and 55, and the insert member 41 serving as the core material were simultaneously extruded. As a result, an extrusion molded body 59 shown in FIG. 6 was extruded. The extrusion speed at this time was set to 5 m/min. The composition of EPDM used in this example is as follows. Compounding amount (M placement part) EPDM
Note 1) 100MAF carbon black 130 paraffin process oil 1o
O Zinc white 5 Stearic acid 1 Dehydrating agent (Cao)
5 Vulcanization accelerator 3.
5 Sulfur 2 Note 1)
rJ 5REP 57CJ Manufactured by Nippon Gosei Com Co., Ltd.
Product name Also, EPD is used as the sponge rubber for the hollow seal part 45.
A mixture of M and a foaming agent was used. Further, as the insert member 41, a plate made of iron was used. Next, vulcanization treatment was performed. This process consists of the extruded body 5
9, a microwave heating device (UHF) mainly for heating
61 and a hot air vulcanizer (HAV) 63 mainly for heat retention.
This was done by passing it through. As the vulcanization conditions at this time, 200°C for 5 minutes was adopted. In this step, the laminated film 40 adhered to the insert member 41 is welded to the rubber base 37 by heat generated during vulcanization of the rubber base 37. In other words, the insert member 41 is adhesively fixed within the rubber base 37. Subsequently, the bonding process for the bonded member 43 was performed. That is, in this step, the member 43 to be adhered to which the laminated film 42 has been adhered is fed out from the roller 65, and in the residual heat immediately after vulcanization, the member 43 to be adhered is welded to the surface of the rubber base 37 by the pressure roller 67. This was done by doing. In addition, the laminated film 40.42 uses an olefin resin Atomer (Mitsui Petrochemical Industries, Ltd.: trade name) as the first film, and a copolymerized polyester resin Chem) R-248 as the second film. (manufactured by Toshi Co., Ltd.: trade name) and were laminated to have film thicknesses of 50 μm and 30 μm, respectively. Further, as the adhered member 43, a woven fabric made of polyester was used. Subsequently, the vulcanized formed body was cooled by a cooler 69 and further bent into a U-shaped cross section by a processing machine 71, thereby completing the weatherstrip 3I shown in FIG. In the above embodiments, the laminated film was laminated only on one side of the insert member, but it may be laminated on both sides of the insert member. In this case, the adhesive force is further strengthened.

【Effect of the invention】

As explained above, according to the insert molded article of the present invention, since the insert member is bonded within the rubber base made of EPDM, it can be molded into a complicated shape by machining. Furthermore, in order to adhere the insert member within the rubber base, a laminated film that adheres to the rubber base and the insert member, respectively, is used, so the adhesive strength is excellent. Furthermore, since the rubber base and the insert member are bonded together at the same time as the rubber base is vulcanized after extrusion molding, it not only improves productivity but also contributes to energy saving.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a method of manufacturing an insert molded body according to an embodiment of the present invention, FIG. 2 is a sectional view showing the insert molded body, FIG. 3 is an explanatory diagram showing the external appearance of an automobile, and FIG. FIG. 5 is an explanatory diagram showing the production line of this embodiment, and FIG. 6 is a sectional view showing an extrusion molded product of this embodiment. 2... Insert molded body 3.41... Insert member 5, 37... Rubber base 7A, 40... Laminated film 11A... First film

Claims (1)

[Scope of Claims] 1. In an insert molded article comprising a rubber base made of EPDM and a metallic insert member embedded in the rubber base, the insert is thermally welded into the rubber base via a laminated film. The laminated film includes a first film made of an olefin resin disposed on the rubber base side and having a polar functional group, and a thermoplastic resin having polarity disposed on the insert member side. An insert molded article characterized by using a laminated product including a second film consisting of: 2 In a method for manufacturing an insert molded body in which a metallic insert member is embedded in a rubber base made of EPDM, the rubber base and an insert member laminated with a laminated film are integrally extruded, and the extruded rubber At the same time as the base is vulcanized at a predetermined temperature, the insert member is thermally welded to the rubber base via a laminated film, and the laminated film is an olefin resin disposed on the rubber base side and having a polar functional group. A method for manufacturing an insert molded article, characterized in that a first film made of the above-mentioned material is laminated with a second film made of a polar thermoplastic resin disposed on the insert member side and made of a polar thermoplastic resin.