Vehicle exterior member

Abstract

A roof rail (1) is provided with a base (2) made of a resin and a coating film (10) having a metallic luster and covering the surface of the base (2), the coating film (10) comprising a primer film (3) attached to the surface of the base (2) and a metal-containing coating film (4) covering the surface of the base (2) with the primer film (3) interposed therebetween, and the film thickness of the metal-containing coating film (4) is greater than the film thickness of the primer film (3).

Description

Technical Field

[0001] This application relates to an external component for a vehicle.

[0002] This application claims priority based on Japanese Patent Application No. 2023-182683, filed on October 24, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] For example, as shown in Patent Document 1, it is sometimes necessary to install roof rails on the roof of a vehicle for loading luggage. Such roof rails are generally provided in two separate sections along the width of the vehicle, with the two roof rails acting as a pair to support the luggage from below.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2009-143276 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] Various exterior vehicle components, such as roof rails as shown in Patent Document 1, are installed on vehicles. These exterior components significantly impact the vehicle's appearance. Sometimes, for example, these components require a metallic sheen. However, if the entire exterior component is made of metal, it increases both material costs and weight. Therefore, most exterior vehicle components use a resin-based substrate that has undergone electroplating. On the other hand, electroplating requires large equipment, so a simpler method has been proposed: forming a metal-containing coating on a resin-based substrate. However, this metal-containing coating forms a primer film covering the substrate surface. In this case, the hue of the primer film can sometimes be visually identified from the outside through the metal-containing coating.

[0009] The present invention was made in view of the above-mentioned problems, and its object is to prevent the color of the primer film from being visually identified by external persons through the metal-containing coating in vehicle exterior parts whose base is made of resin.

[0010] Methods for solving problems

[0011] The present invention employs the following configuration as a means to solve the above-mentioned problems.

[0012] According to a first aspect of the present invention, an exterior component for a vehicle is provided, comprising a base made of resin and a coating film having a metallic luster and covering the surface of the base, wherein the coating film has a primer film attached to the surface of the base and a metal-containing coating film covering the surface of the base in a manner that separates it from the primer film, the thickness of the metal-containing coating film being greater than the thickness of the primer film.

[0013] According to a second aspect of the present invention, in the first aspect described above, the thickness of the metal-containing coating is more than twice the thickness of the primer film.

[0014] According to a third aspect of the present invention, in the first or second aspect described above, the coating film has a protective film that covers the metal-containing coating film from the side opposite to the primer film and is transparent.

[0015] According to a fourth aspect of the present invention, in the third aspect described above, the thickness of the primer film is 5 μm to 10 μm, the thickness of the metal-containing coating film is 20 μm, and the thickness of the protective film is 20 μm to 30 μm.

[0016] According to a fifth aspect of the present invention, a roof longitudinal beam is provided, the roof longitudinal beam comprising vehicle exterior components according to any one of the first to fourth aspects described above.

[0017] According to a sixth aspect of the present invention, in the fifth aspect described above, the surface of the base is an outer side facing the outside of the vehicle, and the coating film is formed to cover the outer side.

[0018] The effects of the invention

[0019] In the above-described manner of the present invention, the metal-containing coating film is thicker, while the primer film is thinner. According to this manner of the present invention, external light can be suppressed from entering the primer film via the metal-containing coating film. Furthermore, even if external light reaches the primer film, the thicker metal-containing coating film prevents external light reflected from the primer film from escaping to the outside. Therefore, according to the above-described manner of the present invention, in vehicle exterior parts with a resin-based base, the color of the primer film can be prevented from being visually identified by external personnel via the metal-containing coating film. Attached Figure Description

[0020] Figure 1 This is a perspective view of the roof of a vehicle having a roof longitudinal beam according to one embodiment of the present invention.

[0021] Figure 2 This is a cross-sectional view of the left roof longitudinal beam, one of the roof longitudinal beams according to an embodiment of the present invention, along... Figure 1 The sectional view observed along line II-II.

[0022] Figure 3 This is a schematic diagram showing the cross-sectional structure of the left roof longitudinal beam, which is one of the roof longitudinal beams according to an embodiment of the present invention. Detailed Implementation

[0023] In the following description, one embodiment of the vehicle exterior component according to the present invention will be explained with reference to the accompanying drawings. Furthermore, in this embodiment, an example of applying the structure of the vehicle exterior component of the present invention to a roof longitudinal beam will be described.

[0024] Figure 1 This is a perspective view of the roof 101 of a vehicle 100 having the roof longitudinal beam 1 of this embodiment. As shown in the figure, the roof longitudinal beam 1 of this embodiment is an elongated member that is longer in the longitudinal direction of the vehicle 100. There are two roof longitudinal beams 1 of this embodiment relative to the vehicle 100. These roof longitudinal beams 1 of this embodiment are arranged at intervals in the vehicle width direction and are parallel to each other.

[0025] The roof longitudinal beam 1 located on the left side of the vehicle 100 is called the left roof longitudinal beam 1A. The roof longitudinal beam 1 located on the right side of the vehicle 100 is called the right roof longitudinal beam 1B. These left roof longitudinal beams 1A and right roof longitudinal beams 1B are formed in a symmetrical shape. Therefore, in the following description, the structure of the left roof longitudinal beam 1A will be described in detail with reference to the accompanying drawings, while the detailed description of the structure of the right roof longitudinal beam 1B will be omitted.

[0026] Figure 2 This is a sectional view of the left-side roof longitudinal beam 1A, equivalent to along... Figure 1 A sectional view taken along centerline II-II. (See attached image.) Figure 2 As shown, the left-side roof longitudinal beam 1A has a main body wall 1a. (As indicated...) Figure 2 As shown, the main body wall 1a is a hollow component with a cross-sectional shape that is approximately hemispherical. The main body wall 1a is formed to open downwards. The outer wall surface 1b of such a main body wall 1a is an exposed surface that can be visually identified from the outside of the vehicle 100. In addition, the inner wall surface 1c of the main body wall 1a is a surface that cannot be visually identified from the outside of the vehicle 100.

[0027] Additionally, the left roof longitudinal beam 1A includes a fastening part (not shown) that is fastened to the vehicle body, or an engaging part (not shown) that engages with the vehicle body. The left roof longitudinal beam 1A is fixed to the vehicle body by these fastening parts and engaging parts.

[0028] Figure 3 This is a schematic diagram showing the cross-sectional structure of the left roof longitudinal beam 1A. As shown in the figure, the left roof longitudinal beam 1A has a base 2, a primer film 3, a metal-containing coating film 4, and a clear coating film 5 (protective film). Among them, the primer film 3, the metal-containing coating film 4, and the clear coating film 5 constitute a coating film 10 covering the surface of the base 2.

[0029] The base 2 is formed of resin. For example, the base 2 is formed of polycarbonate (PC) or polyethylene terephthalate (PET). Such a base 2 can be formed, for example, by injection molding of resin. Such a base 2 is a major part of the main body wall 1a, and like the main body wall 1a, its cross-sectional shape is formed as approximately hemispherical. That is, the base 2 has: a surface facing the outside of the vehicle 100 (a surface that can be visually identified from the outside), namely the outer surface 2a, and a surface on the side opposite to the outer surface 2a (a surface that cannot be visually identified from the outside), namely the inner surface (not shown). In addition, the base 2 may also form the fastening part or engaging part described above.

[0030] The primer film 3 is used to improve the smoothness and adhesion of the metal-containing coating film 4 on the surface of the substrate 2. The surface of the substrate 2 has more unevenness compared to the surface of the primer film 3. Conversely, the surface of the primer film 3 has fewer unevenness than the surface of the substrate 2. By forming the metal-containing coating film 4 on the substrate 2 via such a primer film 3, the adhesion of the metal-containing coating film 4 to the substrate 2 is improved.

[0031] Such a primer film 3 can be formed by applying a paint before it dries to the surface of the substrate 2 and allowing the paint to dry after application. For example, the primer film 3 has a black hue. Such a primer film 3 is formed, for example, with a film thickness of 5 μm to 10 μm. Alternatively, the color of the primer film 3 can also be a color other than black.

[0032] The thickness of the primer film 3 according to this embodiment is less than that of a commonly used primer film (e.g., 20 μm to 25 μm). This thinner primer film 3 prevents solvent components contained in the coating from remaining inside the primer film 3 before drying. Therefore, the influence of residual solvent components inside the primer film 3 on the metal-containing coating film 4 can be suppressed.

[0033] The metal-containing coating 4 is a coating containing a glossy coating that contains metal. For example, the metal-containing coating 4 can be formed using a glossy coating containing metal flakes such as aluminum in a solvent. The solvent contains, for example, a water-soluble resin as a main component other than the metal flakes. The water-soluble resin is, for example, black in color. For example, the metal flakes are in the shape of flakes with a thickness of less than 100 nm and are treated to impart surface hydrophobicity. For example, the metal-containing coating 4 can be formed by applying the glossy coating over a primer film 3 and then allowing the glossy coating to dry. During this drying process of the glossy coating, since the surface of the metal flakes is hydrophobic, the metal flakes are configured to float to the surface of the water-soluble resin, and multiple metal flakes are densely distributed on the surface of the coating, thereby achieving gloss. That is, for example, such a metal-containing coating 4 has metal flakes densely distributed on the surface of the metal-containing coating 4. Therefore, compared to the case where the metal flakes are uniformly dispersed in the metal-containing coating, the uniformity of orientation in the direction parallel to the surface can be further improved.

[0034] The metal-containing coating 4 is formed, for example, with a film thickness of 20 μm. In this embodiment, the film thickness of the metal-containing coating 4 is greater than the film thickness of the primer film 3. Specifically, the film thickness of the metal-containing coating 4 is more than twice the film thickness of the primer film 3. In this way, the layer of the metal-containing coating 4, which is thicker than the primer film 3, is formed by densely packed metal sheets, and the gaps between the metal sheets can be filled. As a result, the gloss of the metal-containing coating 4 can be improved. In addition, the metal-containing coating 4 contains a layer made of dried water-soluble resin in the lower layer (the layer on the primer film 3 side) of the layer formed by densely packed metal sheets. The film thickness of the layer made of water-soluble resin is greater than the film thickness of the layer formed by densely packed metal sheets. With this double-layer structure of the layer formed by densely packed metal sheets and the layer made of water-soluble resin, compared with the conventional case where the metal sheets are uniformly dispersed in the metal-containing coating, the film thickness of the metal-containing coating 4 can be increased while improving the orientation uniformity of the metal sheets.

[0035] By increasing the gloss of the metal coating 4, the specular reflectivity of the metal coating 4 (i.e., the coating film 10) can be improved. Therefore, the absorption rate of external light incident on the left roof longitudinal beam 1A from outside the vehicle can be reduced. Thus, for example, the temperature rise of the left roof longitudinal beam 1A under sunlight exposure can be suppressed.

[0036] The transparent coating 5 is a transparent protective film that covers the metal coating 4 from the side opposite to the primer film 3. Such a transparent coating 5 is formed by applying a transparent coating material overlapping the metal coating 4 and then allowing the transparent coating material to dry. For example, acrylic transparent coatings, polyurethane transparent coatings, silicone transparent coatings, or fluorine transparent coatings can be used as the transparent coating material. The transparent coating 5 is formed, for example, with a film thickness of 20 μm to 30 μm.

[0037] The roof rail 1 of this embodiment includes a base 2 and a coating film 10. The base 2 is made of resin. The coating film 10 has a metallic luster and covers the surface of the base 2. In addition, the coating film 10 has a primer film 3 and a metallic coating film 4. The primer film 3 is attached to the surface of the base 2. The metallic coating film 4 covers the surface of the base 2 in a manner that separates it from the primer film 3. Furthermore, the thickness of the metallic coating film 4 is greater than the thickness of the primer film 3.

[0038] In this embodiment of the roof longitudinal beam 1, the metal coating 4 has a thicker film thickness, while the primer film 3 has a thinner film thickness. According to this embodiment, the roof longitudinal beam 1 can suppress external light from entering the primer film 3 via the metal coating 4. Furthermore, even if external light reaches the primer film 3, the thicker metal coating 4 prevents external light reflected from the primer film 3 from escaping to the outside. Therefore, the roof longitudinal beam 1 according to this embodiment, for roof longitudinal beams with a resin base 2, can prevent the color of the primer film 3 from being visually identified by external personnel via the metal coating.

[0039] Furthermore, in the roof longitudinal beam 1 of this embodiment, the thickness of the metal coating 4 is more than twice the thickness of the primer film 3. According to this embodiment of the roof longitudinal beam 1, the specular reflectivity of the metal coating 4 can be further improved, the color of the primer film 3 can be prevented from being visually identified by external personnel, and the base 2 can be prevented from expanding or contracting due to temperature changes.

[0040] Furthermore, in the roof longitudinal beam 1 of this embodiment, the coating film 10 has a transparent coating film 5 covering the metal coating film 4 from the side opposite to the primer film 3. According to the roof longitudinal beam 1 of this embodiment, the deterioration of the metal coating film 4 can be suppressed by the transparent coating film 5.

[0041] The specular reflectance value of the roof longitudinal beam 1 of this embodiment was measured using a VC-2 colorimeter from SUGA Testing Machine Co., Ltd. The specular reflectance value is the L value, which represents the brightness of the specularly reflected light; a higher specular reflectance value indicates higher reflectivity and a brighter color. For comparison, measurements were also taken under the same conditions for a roof longitudinal beam with a coating instead of the coating 10, a roof longitudinal beam with a satin-finish coating instead of the coating 10, and a roof longitudinal beam made of aluminum.

[0042] The specular reflectance value of the roof longitudinal beam 1 in this embodiment is 500. Furthermore, the specular reflectance value of the roof longitudinal beam with a coating is 785. Additionally, the specular reflectance value of the roof longitudinal beam with a satin-style coating is 437. The specular reflectance value of the roof longitudinal beam made of aluminum is 622. Based on these measurement results, it can be seen that the specular reflectance value of the roof longitudinal beam 1 in this embodiment is higher than that of the roof longitudinal beam with a satin-style coating, and is close to that of the roof longitudinal beam made of aluminum or the roof longitudinal beam with a coating. Therefore, it can be concluded that the roof longitudinal beam 1 of this embodiment has the same metallic luster as the coating or aluminum.

[0043] Furthermore, in the coating film 10 of the roof longitudinal beam 1 in this embodiment, the thickness of the primer film 3 is 5 μm to 10 μm, the thickness of the metal coating film is 20 μm, and the thickness of the clear coating film 5 is 20 μm to 30 μm. That is, as can be seen from the above measurement results, by setting the thicknesses of the primer film 3, the metal coating film 4, and the clear coating film 5 within the above ranges, the roof longitudinal beam has a good metallic luster.

[0044] Furthermore, in the roof longitudinal beam 1 of this embodiment, the base 2 has a surface facing the outside of the vehicle 100, namely the outer surface 2a. Additionally, the coating 10 is formed to cover the outer surface 2a. According to this embodiment, the roof longitudinal beam 1, since the coating 10 is provided on the outer surface 2a, can reflect sunlight and suppress the base 2 from heating up due to sunlight exposure.

[0045] While preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these embodiments. The various shapes or combinations of the constituent components shown in the above embodiments are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0046] For example, in the above embodiments, an example of applying the vehicle exterior component of the present invention to a roof longitudinal beam was described. However, the present invention is not limited thereto. The present invention can be applied to vehicle exterior components that can be visually identified from the outside of the vehicle.

[0047] Explanation of reference numerals in the attached figures

[0048] 1...Roof longitudinal beams (external components for vehicles); 1a……Main wall section; 1A……Left roof longitudinal beam (external vehicle component); 1b...external wall surface; 1B...Right roof longitudinal beam (external vehicle component); 1c...inner wall surface; 2...base; 2a……outer surface; 3... Primer film; 4...containing metallic coatings; 5... Transparent coating (protective film); 10……covered with film.

Claims

1. An exterior component for a vehicle, comprising a base made of resin and a coating having a metallic sheen and covering the surface of said base, wherein, The coating film has the following characteristics: A primer film is attached to the surface of the substrate; as well as A metallic coating is applied to the surface of the substrate, in a manner that separates it from the primer film. The thickness of the metal-containing coating is greater than the thickness of the primer film.

2. The vehicle exterior component according to claim 1, wherein, The thickness of the metal-containing coating is more than twice the thickness of the primer film.

3. The vehicle exterior component according to claim 1 or 2, wherein, The coating film has a protective film that covers the metal-containing coating film from the side opposite to the primer film and is transparent.

4. The vehicle exterior component according to claim 3, wherein, The thickness of the primer film is 5 μm to 10 μm. The thickness of the metal coating is 20 μm. The thickness of the protective film is 20 μm to 30 μm.

5. A roof longitudinal beam, wherein, Includes vehicle exterior components according to any one of claims 1 to 4.

6. The roof longitudinal beam according to claim 5, wherein, The surface of the base is the outer side facing the outside of the vehicle. The coating is formed to cover the outer surface.

Images