Weather strip

Abstract

To provide a weather strip capable of securing water cut-off performance, while maintaining abnormal sound preventive performance, even if a filler exists in a coating film formed on a surface.SOLUTION: A weather strip (200) includes a mounting base (10) attached to a peripheral edge of an opening / closing body (1) or a peripheral edge of an opening of a body (2), and a seal part (20) integrally formed with the mounting base (10) and having a coating film (50) formed thereon, the coating film (50) including a base (60) and a filler (70) added to the base (60). The filler (70) has a mean particle size of 15 to 20 μm and a 10% deformation strength of 0.1 1MPa or less.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a weatherstrip that is attached to the periphery of an opening / closing body such as an automobile side door, back door, trunk lid, or hood, or to the periphery of an opening in the body, and elastically contacts the body side or the opening / closing body when the opening / closing body is closed, thereby sealing between the opening / closing body and the body. [Background technology]

[0002] Conventionally, as shown in Figures 1 and 2, a weatherstrip (door weatherstrip) 200 has been known which includes a mounting base 10 that is attached to the periphery of an opening / closing body 1 such as a vehicle door, and a hollow sealing portion 20 that is integrally molded with the mounting base 10 and has a coating film 50 formed on its surface, which elastically contacts the periphery of the opening on the body 2 side when the opening / closing body 1 is closed (see, for example, Patent Document 1).

[0003] It is also known that fillers such as silicone particles or polyurethane gel particles are added to the coating 50 of automotive weatherstrips to improve noise prevention (see Patent Documents 2 and 3). The noise referred to here refers to the creaking noise that occurs when the weatherstrip slides against the body due to vibrations during driving, and is particularly likely to occur when the weatherstrip is slightly wet, such as in rainy weather, and is one of the factors that deteriorates vehicle quality. Adding fillers improves slipperiness and reduces the occurrence of creaking noise. On the other hand, as shown in Table 1, fillers with larger particle sizes tend to improve noise prevention, but have poorer water-stopping properties compared to fillers with smaller particle sizes. This is thought to be due to the effect that, when the opening / closing body 1 is closed and the weatherstrip 200 comes into contact with the body 2, tiny gaps are created between the filler present on the surface of the paint film 50 of the seal portion 20 and the body 2. In other words, as shown in Figure 3(a), when a filler with a small particle size is added, the gaps are smaller than when a filler with a large particle size is added, so the amount of water that can penetrate is small and the watertightness is good, whereas, as shown in Figure 3(b), when a filler with a large particle size is added, the gaps are larger than when a filler with a small particle size is added, so the watertightness is thought to be worse.

[0004] [Table 1]

[0005] Thus, conventional automotive weatherstrips in which a coating film containing fillers is formed on the surface of the sealing portion have trade-offs between noise prevention and water-stopping properties. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 7418641 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-1710 [Patent Document 3] Japanese Patent Application Laid-Open No. 2000-313234 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide a weatherstrip that can maintain noise prevention properties and ensure watertightness even if a filler is present in the coating film formed on the surface of the sealing portion. [Means for solving the problem]

[0008] In order to achieve the above object, the weatherstrip of the present invention is a weatherstrip (200) comprising an attachment base (10) attached to the periphery of an opening / closing body (1) or the periphery of an opening in a vehicle body (2), and a seal portion (20) integrally formed with the attachment base (10) and elastically contacting the periphery of the opening in the body (2) or the periphery of the opening / closing body (1) when the opening / closing body (1) is closed, A coating film (50) is formed on the surface of the sealing portion (20), in which a filler (70) is added to a base (60), and the filler (70) has an average particle size of 15 to 20 μm and a 10% deformation strength of 0.1 MPa or less.

[0009] The present invention is also characterized in that the base (60) has a hardness of 46 MPa or less when measured with a nanoindentation tester with the maximum indentation load of the indenter set to 20 μN.

[0010] The present invention is also characterized in that the thickness (S) of the base (60) is 20 μm or less.

[0011] It should be noted that symbols in parentheses indicate corresponding elements or matters described in the drawings and in the detailed description to be described later. [Effects of the Invention]

[0012] According to the present invention, in a weatherstrip comprising a mounting base that is attached to the periphery of a vehicle's opening / closing body or the periphery of a body opening, and a sealing portion that is integrally molded with the mounting base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, and that has a coating film formed on its surface to which a filler is added in a base, the average particle diameter of the filler is large at 15 to 20 μm, thereby improving the noise prevention properties of the sealing portion. In addition, since the 10% deformation strength of the filler is small at 0.1 MPa or less, the filler sandwiched between the sealing portion and the opposing part (the periphery of the body opening if the weatherstrip is attached to the periphery of a vehicle opening such as a door, or conversely, the periphery of the opening / closing body if the weatherstrip is attached to the periphery of a body opening) deforms, thereby reducing the gap between the filler and the opposing part, thereby preventing a deterioration in watertightness. In this way, by using a filler with a large particle size and a small 10% deformation strength, it is possible to achieve both noise prevention and water-stopping properties.

[0013] Furthermore, according to the present invention, the hardness of the base is 46 MPa or less when measured using a nanoindentation tester with the maximum indentation load of the indenter set to 20 μN, thereby further improving noise prevention.

[0014] Furthermore, according to the present invention, the average particle size of the filler is 15 to 20 μm, while the thickness of the base is set to 20 μm or less, so the amount of filler that is not exposed on the surface of the coating film is reduced, allowing the filler's capabilities to be fully utilized. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view showing a weatherstrip 200 according to an embodiment of the present invention. [Figure 2] 2 is a cross-sectional view showing a state in which the weatherstrip 200 shown in FIG. 1 is bent. [Figure 3] FIG. 3 is an enlarged cross-sectional view taken along line AA in FIG. 2, schematically showing a main part of a weatherstrip 200 on which a coating film is formed according to a conventional example. [Figure 4] FIG. 3 is an enlarged cross-sectional view taken along line AA in FIG. 2, schematically showing a main part of a weatherstrip 200 on which a coating film according to an embodiment of the present invention is formed. DETAILED DESCRIPTION OF THE INVENTION

[0016] A weatherstrip 200 according to an embodiment of the present invention will be described with reference to FIGS. 1, 2 and 4. FIG. This weatherstrip 200 comprises a mounting base 10 that is attached to the opening and closing body 1 of the vehicle, in this case the side door 1, and a hollow sealing portion 20 made of sponge rubber that is integrally molded with the mounting base 10 and elastically contacts the periphery of the opening of the body 2 when the side door 1 is closed, and has a coating film 50 formed on its surface. The thickness of the coating film 50 in the drawing is an image for ease of understanding; the actual thickness of the coating film is in μm (microns), while the thickness of the hollow seal portion 20 is in mm (millimeters), so the thickness of the coating film is on the order of approximately 1 / 1000 of the thickness of the hollow seal portion 20.

[0017] The sponge rubber used for forming the hollow seal portion 20 of the weatherstrip 200 according to the embodiment of the present invention has a specific gravity of 0.40.

[0018] The specific gravity can be determined by separating the hollow seal portion 20 of the weatherstrip 200 by cutting it off or the like, and then subjecting it to an underwater displacement method.

[0019] The hollow seal portion 20 is made of a rubber material mainly composed of EPDM (ethylene propylene diene rubber), but is not limited to EPDM, and may be made of rubber materials mainly composed of other synthetic rubbers or various thermoplastic elastomers.

[0020] 4, the coating film 50 formed on the surface of the hollow seal portion 20 is made by adding filler 70 to a base 60, and the average particle size of the filler 70 in the coating film 50 is set to 15 to 20 μm, and the 10% deformation strength of the filler 70 is set to 0.1 MPa or less. Here, filler 70 with an average particle size of 20 μm and a 10% deformation strength of 0.1 MPa was used.

[0021] This is because, as shown in Table 2 below, the evaluation revealed that the larger the average particle size of the filler is, from 8 μm to 15 μm to 20 μm, the better the noise prevention performance, and as shown in Table 3, the smaller the 10% deformation strength is, from 25.0 MPa to 10.0 MPa to 0.5 MPa to 0.1 MPa, the better the water-stopping performance.

[0022] The 10% deformation strength of the filler was measured using a microparticle crushing force measuring device, Model NS-A300 (manufactured by Nano Seeds Co., Ltd.), in accordance with JIS Z 8844: 2019, the method for measuring the breaking strength and deformation strength of microparticles. The particle diameter was measured using image analysis software, and the diameter (length) of the particle sandwiched between the indenter and the flat surface to which the particle was attached was measured from the image taken during measurement.

[0023] Although silicone particles are used as filler 70, other materials such as polyethylene, nylon, acrylic, urethane, and fluorine may be used as long as the 10% deformation strength is 0.1 MPa or less.

[0024] The base 60 is made by blending a carbodiimide-based curing agent with an aqueous polyurethane resin (solid content 30%), but is not particularly limited to this.

[0025] The hardness of the base 60 is preferably 46 MPa or less, and here, a hardness of 46 MPa was used.

[0026] This is because, as shown in Table 4 below, evaluation revealed that the lower the hardness of the base 60 was, from 205 MPa to 122 MPa to 46 MPa to 26 MPa, the better the noise prevention properties were.

[0027] The hardness of the base 60 was measured in accordance with ISO 14577 using an Anton Paar "UNHT3" nanoindentation tester and a Berkovich indenter, with the maximum indentation load of the indenter set to 20 μN and the loading / unloading rate set to 600 μN / min. The hollow seal portion 20 was cut into a square measuring 10 mm in length and 10 mm in width, which was used as the measurement specimen. The thickness of the measurement specimen was approximately 1.8 mm.

[0028] The weight ratio of the filler 70 to the base 60 is preferably 1 part filler 70 to 6 parts base 60 or less, and here the filler 70 was mixed in a ratio of 1 part filler to 2 parts base 60.

[0029] The noise prevention evaluation in Tables 2 and 4 was based on a sensory evaluation of the creaking noise generated in semi-wet conditions, with "○" indicating that no noise was generated, "△" indicating that slight noise was generated, and "×" indicating that noise was generated. The watertightness evaluation in Table 3 was conducted by simulating rainy weather and evaluating water leakage when the weatherstrip elastically contacted the opposing surface. Water was supplied to the elastic contact area and the time it took for it to pass through was measured. "○" indicates 30 minutes or more, "△" indicates 10 to less than 30 minutes, and "×" indicates less than 10 minutes.

[0030] From the viewpoint of filler exposure, the thickness S of the base 60 is preferably 20 μm or less. More preferably, it is 17 μm or less, and even more preferably, it is 15 μm or less. Here, the thickness S of the base 60 is set to 20 μm. There is no particular lower limit to the thickness S, but from the viewpoint of maintaining the durability of the hollow seal portion 20, it is preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more.

[0031] The thickness S of the base 60 was measured using image analysis software, measuring the vertical length of the base 60 relative to the hollow seal portion 20 at the measurement point from an image of the cross-sectional surface of the hollow seal portion 20 enlarged and displayed using a digital microscope.

[0032] [Table 2]

[0033] [Table 3]

[0034] [Table 4]

[0035] According to the weatherstrip 200 configured in this manner, the average particle diameter of the filler 70 of the coating film 50 formed on the surface of the hollow seal portion 20 is large at 15 to 20 μm, thereby improving the prevention of abnormal noise when the hollow seal portion 20 is in elastic contact with the periphery of the opening of the body 2. In addition, since the 10% deformation strength of the filler 70 is small, at 0.1 MPa or less, as shown in Figure 4, the filler 70 sandwiched between the hollow seal portion 20 and the opposing part (the periphery of the opening of the body 2) deforms, thereby reducing the gap between the filler and the opposing part (the periphery of the opening of the body 2), thereby preventing a deterioration in watertightness. In this way, by using a filler with a large particle size and a small 10% deformation strength, it is possible to achieve both noise prevention and water-stopping properties.

[0036] Furthermore, since the hardness of the base 60 is set to 46 MPa or less, noise prevention can be further improved.

[0037] Furthermore, since the average particle diameter of filler 70 is 15 to 20 μm and the thickness of the base is set to 20 μm or less, the amount of filler 70 that is not exposed on the surface of the coating film is reduced, allowing filler 70 to fully demonstrate its capabilities.

[0038] In this embodiment, the door weatherstrip 200 is attached along the periphery of the side door 1 and elastically contacts the periphery of the opening of the body 2. However, the door weatherstrip may be attached along the periphery of the opening of the body 2 and elastically contacts the periphery of the side door 1 when the door is closed. The hollow seal portion 20 may be solid, such as a lip. The hollow seal portion 20 is not limited to being made of sponge rubber, and may be configured as a single layer of solid rubber or a multi-layer of solid rubber and sponge rubber. The specific gravity of the sponge rubber may be higher or lower than 0.40. The invention is applicable to any weatherstrip, such as a weatherstrip attached to an opening / closing body such as a back door, trunk lid, or hood of an automobile. [Explanation of symbols]

[0039] 1 Opening and closing body (side door) 2 Body 10 Mounting base 20 Hollow seal part 50 coating 60 base 70 Filler 200 Weatherstrip W water

Claims

1. A weatherstrip comprising: an attachment base portion attached to a periphery of an opening / closing body or a periphery of a body opening of a vehicle; and a seal portion integrally formed with the attachment base portion and elastically contacting the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, A coating film having a base and a filler added thereto is formed on the surface of the sealing portion, The weatherstrip is characterized in that the filler has an average particle size of 15 to 20 μm and a 10% deformation strength of 0.1 MPa or less.

2. 2. The weatherstrip according to claim 1, wherein the base has a hardness of 46 MPa or less when measured with a nanoindentation tester with a maximum indentation load of an indenter set to 20 μN.

3. 3. The weather strip according to claim 1, wherein the thickness of the base is 20 μm or less.

Images