JP2000108807A - Weather strip for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the seal part from causing a kink phenomenon, and to reduce waste by arranging the recoverable/reusable part by forming a seal member of a cross-linked/reacted foaming rubber material, and forming a trim member of thermoplastic elastomer. SOLUTION: In a seal member 3, a rubber material, desirably, ethylene propylene rubber and an additive are kneaded, and unvulcanized rubber is supplied to a rubber extruder. The seal member is molded by a die arranged on the tip of the extruder, and is cut out after being heated and vulcanized. A trim member 5 is molded by supplying a pellet of thermoplastic elastomer to the extruder, and is cut out in a desired dimension, that is, in the same length as the seal member 3. The seal member 3 is a hollow shape, and the seal member engaging part 9 is arranged. The trim member 5 is formed by using a metallic plate as a hard core material, and the seal member engaging part 9 being the recessed part for engaging the seal member 3 is fitted to the trim member engaging part 11 to be engaged with the trim member 5 to form this weather strip.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weather strip used for preventing rainwater or the like from entering the inside of an opening / closing section of an automobile. A weatherstrip including a trunk seal used for a trunk portion, a cowl seal used for a bonnet portion, and the like,
The present invention relates to a weatherstrip provided with a seal member made of a foamed elastic material and a non-foamed or low-foamed trim member, and is suitably used especially as a trunk seal among the above.

[0002]

2. Description of the Related Art Conventionally, as a material for forming a weather strip for an automobile, a rubber material of a cross-linking reaction type such as polychloroprene rubber and ethylene propylene rubber (EPDM) has been used. It was formed of a crosslinked rubber. However, it is difficult to reuse cross-linked rubber, so it is cut into chips and solidified with a binder for use as sheets or blocks, or as an industrial waste except for burning to make a part of fuel. In addition, there has been a need to switch to reusable materials from the viewpoint of reducing waste and protecting the environment.

[0003] As a reusable material, a thermoplastic elastomer has been studied and improved as a weatherstrip material, and is already known, and is a weatherstrip in which a sealing member and a trim member are integrated. What is formed is known in the art.
-246646).

[0004]

Incidentally, the weather strip is a member having a shape having a seal portion generally formed of a foamed elastic member having a hollow portion.
A movable part, such as a trunk cover, and a fixed part, such as a trunk frame of the vehicle body, are attached to the fixed part by a method such as fitting a trim member mainly at an openable and closable position, and contact with an end of the movable part. The sealing member is subjected to compressive deformation and exerts a sealing effect by a restoring force based on its rubber-like elasticity. Therefore, if the permanent set is large, the sealing ability based on the restoring force is reduced, so that the original purpose cannot be achieved.

[0005] A thermoplastic elastomer is essentially a material having a permanent set greater than that of a crosslinked rubber material at the same hardness because the molecules do not have a crosslinking point, and is a foamed elastic material using a conventional crosslinked rubber. In order to achieve the same permanent set as that of the seal portion made of the member, it is necessary to increase the hardness of the thermoplastic elastomer. In this case, if a small curvature radius such as a corner portion of the trunk is given, the thermoplastic elastomer foam described in JP-A-7-246646 is bent, causing a so-called kink phenomenon, and the sealing performance of this portion is greatly reduced. Also, the appearance quality is not preferable.

An object of the present invention is to provide a kink phenomenon even when a solid portion is made of a thermoplastic elastomer and a foamed elastic member constituting a seal portion is made of a crosslinked rubber foam and has a small curvature radius. Another object of the present invention is to provide a weatherstrip which does not cause a problem and is provided with a portion which can be recovered and reused to reduce waste.

[0007]

SUMMARY OF THE INVENTION The present invention is an automotive weatherstrip in which a seal member and a trim member are engaged, wherein the seal member is a cross-linked foamed rubber material, and the trim member is a thermoplastic member. It is an elastomer.

[0008] With this configuration, the use of a foamed rubber material that has undergone a cross-linking reaction as the seal member prevents the seal portion from having a kink phenomenon even in a curved portion having a small radius of curvature. Since there is no reduction and the trim member can be recovered and reused, industrial waste can be reduced. It is environmentally preferable that the trim member constituent resin is a resin containing neither a halogen element nor a plasticizer such as a phthalate ester.

[0009] The seal member does not need to be entirely foamed, but may have a partially solid rubber portion in cross-sectional shape. In particular, the seal member engaging portion engaging with the trim member is a cross-linked solid member. Rubber is preferable, and the engagement strength can be increased.

The crosslinked foamed rubber used for the weather strip of the present invention has a density of about 0.2 to 0.7 as a material, and the crosslinked solid rubber and the thermoplastic elastomer of the solid portion have a density of about 0.1 to 0.7. Those having about 7 to 1.2 are preferably used.

[0011] In the weather strip of the present invention,
It is preferable that the trim member is further combined with a hard core material.

The shape retention of the weatherstrip as a whole is improved, more excellent sealing properties are obtained when the weatherstrip is used for a seal portion of a trunk, and the weatherstrip can be securely attached to a fixed portion.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the weather strip of the present invention, known materials can be used as the crosslinked rubber material constituting the sealing member without any particular limitation. In particular,
Examples of the rubber material include diene rubbers such as chloroprene rubber, ethylene propylene rubber, styrene butadiene rubber, butadiene rubber, and isoprene rubber, natural rubber, and acrylic rubber, and can be used alone or in combination of two or more. Considering the burning treatment, it is preferable to use a rubber material containing no halogen element.

The above rubber material is used by adding known fillers, process oils, plasticizers, auxiliaries, accelerators, antioxidants and the like, if necessary, together with a crosslinking agent and a foaming agent.
Known crosslinking methods such as sulfur vulcanization and peroxide vulcanization can be used without particular limitation.

Known blowing agents can be used without limitation. Specifically, sodium bicarbonate,
Inorganic blowing agents such as ammonium bicarbonate, nitroso compounds such as N, N'-dinitrosopentamethylenetetramine,
Azodicarbonamide, azo compounds such as azobisisobutyronitrile, benzenesulfonyl hydrazide, sulfonyl hydrazides such as toluenesulfonyl hydrazide,
Examples thereof include p-toluenesulfonyl semicarbazide. It is also preferable to use salicylic acid, urea and a foaming aid containing these together with these foaming agents.

As the thermoplastic elastomer used in the solid portion of the present invention, known thermoplastic elastomers can be used without limitation, and polyamide elastomers, polyester elastomers, polyolefin elastomers, and other polyolefin resins such as vulcanized rubber Examples thereof include a thermoplastic elastomer composited with particles and the like.

Among the combinations of materials exemplified above, ethylene propylene rubber (EPDM, EPR), butyl rubber (IIR),
Halogen-free diene rubbers such as styrene butadiene rubber (SBR), butadiene rubber (BR) and isoprene rubber (IR) are used, and as a thermoplastic elastomer, IIR, EPDM, EPR, NBR, or polyolefin elastomer or polyolefin resin is used. IIR, SB
A combination using a thermoplastic elastomer in which vulcanized rubber particles of one or more rubbers selected from R, BR and natural rubber are dispersed is particularly preferred. With this configuration, when the elastic material including the seal member is finely pulverized and the polyolefin resin is added, the entire polymer component can be reused as the thermoplastic elastomer without separating the vulcanized rubber and the thermoplastic elastomer. Become.

In the present invention, a material usable as a hard core material is a material used as a hard core material of a weatherstrip using a conventional crosslinking reaction type rubber material.
It can be used without any particular limitation, and examples thereof include metal materials such as iron, aluminum, brass, copper, and stainless steel, and highly rigid resins such as polyphenylene sulfide, polyacrylic resin, and ABS resin. Especially equipped with notches and spaces,
A ribbon-shaped steel plate that can be bent to a predetermined shape if necessary, and that is a continuous hard core material during weather strip production, but that can be finally separated into a predetermined length by external force such as bending Use is preferred.

When a metal is used as a hard core material, it is possible to separate and recover the metal core material and the resin by melting the resin and using a strainer or the like. Depending on the material, the resin constituting the hard core material may be dissolved, and the whole may be reused as a thermoplastic elastomer or a thermoplastic resin.

In the weather strip of the present invention, the engagement method for engaging the seal member and the trim member has a function of preventing the intrusion of rainwater or the like without the product after engagement being separated during transportation or mounting. The method is not particularly limited as long as the method is used. Specifically, a fitting method, bonding with an adhesive, an engaging method using an engaging member, and the like are exemplified.
However, considering that one of the main objects of the present invention is the recovery and reuse of the material, the sealing member using the crosslinked rubber and the solid portion using the thermoplastic elastomer are engaged so that they can be easily separated. And the above-mentioned fitting method is particularly suitable.

It is preferable that at least a part of the surface of the weatherstrip of the present invention is coated with a coating agent. In particular, the surface of the sealing member is adhered to a movable member, for example, a window glass, or slides. It is preferable to have a coating agent layer in order to prevent abrasion. As such a coating agent, it is particularly preferable to apply a polyurethane-based paint from the viewpoint of abrasion resistance. In order to reduce the surface friction coefficient of the coating film, a silicone-based compound or a fine powder of a fluororesin is contained. It is also a preferred embodiment to provide a coated film.

The method of manufacturing a weather strip according to the present invention will be described below. For the sealing member, a predetermined rubber material, preferably EPDM, and additives are kneaded by a method well known to those skilled in the art, and the unvulcanized rubber is supplied to a rubber extruder as a ribbon. The unvulcanized rubber is extruded into a desired shape by a die provided at the end of the extruder, and then sent to a heating and vulcanizing device. The rubber material foamed and vulcanized in the heating vulcanizing device is a continuous sealing member, which is cut into a predetermined size.

The crosslinked solid rubber portion such as a seal member engaging portion provided on the seal member as necessary is formed by a known method. To illustrate specifically, an unvulcanized rubber raw material that does not contain a foaming agent and a foamed rubber raw material are supplied to separate extruders each arranged to have a common die,
It is formed by extruding separately, joining at the same time with the die, and feeding the vulcanizer.

The trim member is supplied to a thermoplastic resin extruder by pellets of a thermoplastic elastomer compounded in a predetermined composition, formed into a predetermined shape by a die provided at the tip of the extruder, cooled, and continuously cooled. A solid portion is formed. This is cut into a desired size, that is, the same length as the sealing member, and is used for manufacturing the weather strip of the present invention. When a hard core material is used, the hard core material is supplied to the extruder head at a predetermined speed in a continuous state from a direction different from the screw axis of the extruder, and the molten and extruded thermoplastic elastomer is formed of metal. The hard core material is coated with a predetermined thickness and shape by the mold. The extruded trim member is cut to a predetermined length. After the trim member is cut, the hard core material is separated into lengths of 0.5 to several cm, and the trim member is processed so as to be flexible as a whole.

After the seal member and the trim member manufactured by the above-described steps are engaged, the ends are joined as necessary, and then processed into an endless shape. The joining method of the ends is performed by using an adhesive using an adhesive, or using a mold having an outer mold and a middle mold that match the outer shape and inner shape of the weather strip. Examples include an injection molding method in which a vulcanized rubber or a thermoplastic resin is injection-molded, an unvulcanized rubber is cured by crosslinking, and a thermoplastic resin is cured and bonded by cooling, and can be used without limitation.

An example of a weather strip according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a cross section of the seal member 3 and the trim member 5 before engagement, and shows an example in which the entire seal member 3 is a foam. Seal member 3
Has a hollow shape and is provided with a seal member engaging portion 9. The trim member 5 is formed by using a metal plate as a hard core material, and is provided with a trim member engaging portion 11 which is a concave portion for engaging a seal member. The engagement with the engagement portion 11 engages with the trim member 5 to form a weather strip.

The engagement may be simple physical engagement, or at least partially using an adhesive, a clip, or the like. Since the foam easily undergoes compressive deformation, it is a preferable embodiment to form at least a part of the seal member engaging portion 9 larger than the trim member engaging portion 11 in order to increase the engaging force. In this example, the neck portion on which the seal member engaging portion 9 is erected is formed larger than the opening of the trim member engaging portion 11.

FIG. 2 is a sectional view showing an example of a sealing member and a trim member of a weather strip of a type in which two kinds of sealing members are mounted. In this example, a part of the seal member is made of solid rubber and the seal member engagement portions 9a, 9a are used.
b. The weather strip of FIG. 2 has seal member engaging portions 9a and 9b formed in a concave shape and trim member engaging portions 11a and 11b formed in a convex shape, and is configured to be fittable. And the sealing member 3 and the trim member 5
The engaging portion 13 is provided on the seal member engaging portion 9, and the engaging portion 15 is provided on the trim member engaging portion 11 so that the engagement is not easily released.
Are provided respectively. Regarding the shape of the engaging portion, any of the seal portion and the trim portion may be concave and any of the convex portions may be convex.

As described above, FIG. 2 shows an example in which the crosslinked solid rubber is formed in a concave shape as the seal member engaging portion. When the crosslinked solid rubber is made concave, the permanent elongation is small, so the permanent rubber is caused by permanent elongation in the engaged state as compared with the case where the trim portion using a thermoplastic elastomer is made concave to receive elongation stress. This is more preferable because separation due to a decrease in engagement force is less likely to occur.

FIG. 3 shows an example of the shape of the seal member engaging portion 9a and the trim member engaging portion 11a. The shape of the trim member engaging portion 11a forms a fitting concave portion, and the engaging portion 13 for preventing the detachment of the seal member engaging portion 9a has a thickness r of 2 to 5 m.
m and the width q are preferably 2 to 5 mm, and the opening for receiving the seal member engaging portion 9 a preferably has a width of 1 to 3 mm. Preferably, the locking portion of the seal member engaging portion 9a has a thickness of 2 to 5 mm. If it is smaller than this range, the engagement strength will be insufficient, and if it exceeds this range, the shape of the engagement portion will be too large to meet the requirements of the trunk seal.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a weather strip in which a sealing member is entirely formed of a foam.

FIG. 2 is a view showing an example of a weather strip in which only a sealing member engaging portion of a sealing member is formed of a non-foamed material.

FIG. 3 is a view showing an example of a shape of a seal member engaging portion and a trim member engaging portion.

[Explanation of symbols]

 3 Seal member 5 Trim member

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D024 AA02 AA17 AB06 AB18 AB34 AB57 4F100 AL09B AN00A AR00C BA02 BA03 BA10A BA10B DB02 DB13 DJ01A EJ02A EJ05A GB36 JB16B JK12 JL01 JL16

Claims (6)

[Claims] 1. A weather strip for an automobile in which a seal member and a trim member are engaged, wherein the seal member is a member including a foam seal portion formed of a foamed rubber material that has undergone a cross-linking reaction, and the trim member Is an automotive weatherstrip made of a thermoplastic elastomer. 2. The automotive weather strip according to claim 1, wherein said trim member is further combined with a hard core material. 3. The seal member has a seal member engaging portion, and the trim member has a trim member engaging portion. The seal member and the trim member have a seal member engaging portion and a trim member engaging portion. 3. The weatherstrip for an automobile according to claim 1, wherein the weatherstrip is formed by fitting. 4. The automotive weather strip according to claim 3, wherein said seal member engaging portion is concave with a locking portion, and said trim member engaging portion is convex with a locking portion. 5. The automotive weather strip according to claim 3, wherein said seal member engaging portion is formed of a solid rubber that has undergone a crosslinking reaction. 6. A cross section of the locking portion of the sealing member engaging portion has a thickness of 2 to 5 mm, a width of 2 to 5 mm, and an opening of 1 to 3 mm.
The weatherstrip for an automobile according to any one of claims 3 to 5, wherein the locking portion of the trim member engaging portion has a cross-sectional thickness of 2 to 5 mm.