Method of manufacturing a vehicle component

Abstract

The method for manufacturing a vehicle component (2) comprises a step of applying a paint layer (6) on a transparent or translucent component (4), and a step of locally irradiating the paint layer (6) with laser radiation (10) in order to etch the paint layer (6) in part of its thickness according to a predetermined pattern.

Description

Field of the Invention

[0001] The present invention relates to a motor vehicle part. More specifically, the present invention relates to a method for manufacturing a transparent vehicle part that contributes to the appearance of the vehicle. Background Art

[0002] Vehicles include a plurality of transparent parts intended to transmit light. In particular, parts for legal lighting purposes, such as parts that protect the optical assemblies of road and turn signal or flash lamps. The vehicle may also have light sources provided for decorative purposes, which improve the aesthetics of the vehicle.

[0003] For these purposes, the surface of the transparent part can be treated to improve its appearance. To this end, a feasible solution lies in overmolding a film with a predetermined opaque pattern on the surface of the transparent part. Thus, when the light source associated with the transparent part emits light, due to the opacity of the pattern, the light is partially blocked and partially passes through the part that is not covered by the pattern. This can improve the aesthetics of the light beam transmitted through the transparent part from the light source towards the external environment. Another feasible solution lies in decorating the transparent part by painting and pasting, which can also achieve a similar effect.

[0004] These options make sense, but they may cause problems. In fact, the film or pasting as described above may cause problems corresponding to the color of the vehicle paint, which has an adverse effect on the aesthetics of the vehicle. Moreover, applying the film or pasting may not obtain a pattern with the desired precision. Moreover, these techniques may cause aging problems.

[0005] To remedy these drawbacks, for example, in document FR 1912347 A1, it is known to apply a paint layer on the transparent part and then apply laser irradiation etching according to a predetermined pattern. This removes the paint layer over the entire thickness of the paint layer in the pattern area, which allows light to pass through the transparent part in the pattern area. However, this solution is not entirely satisfactory because the problem lies in that light passes through the areas of the transparent part that are not covered by the pattern. In fact, the light passes freely through these parts, so that if the light source associated with the transparent part is extinguished, the elements located behind the part can be seen from the outside. This mainly concerns the light source and possibly the wiring elements. The exposure (visibility) of these elements is not desired because it is not conducive to the overall aesthetics of the vehicle, and thus it is preferably avoided. Summary of the Invention

[0006] The object of the present invention is in particular to solve these problems by proposing a method that does not cause color matching problems with the vehicle paint, that is more precise than the prior art, and that can hide the elements located behind the transparent part.

[0007] To this end, the subject of the present invention is a method for manufacturing a vehicle component, which comprises the following steps:

[0008] - applying a paint layer on one side of a transparent or translucent component, the paint layer being single-layer; and

[0009] - locally irradiating the paint layer with laser radiation to etch the paint layer in a part of its thickness according to a predetermined pattern.

[0010] Thus, the paint can be applied on one side of the transparent component, and then, according to the selected predetermined pattern, a part of the thickness of the paint is removed by etching using laser radiation. In other words, only a residual layer of the paint is retained in the predetermined pattern area. It can be understood that, compared with implementing any of the above-mentioned prior art methods, the laser can remove the paint to obtain a more precise rendering. Moreover, the cladding color is provided by the paint, rather than by a film or a sticker as in the prior art, which enables the selection of a paint corresponding to the paint layer used for the vehicle body. Thus, fewer color correspondence problems occur. In addition, the manufacturing method only implements a single step of applying a cladding (i.e., a paint layer) on a transparent or translucent component, which enables the method to only require a single pass in the workshop where the paint is applied or in the deposition chain (which should be understood broadly here). This helps to make the manufacturing method simple and fast to implement, and more generally, makes the manufacturing method more competitive industrially.

[0011] The residual paint layer present in the pattern area enables preventing the line of sight from passing through (seeing through) the transparent or translucent component when the light source combined with the transparent or translucent component is turned off, but does not prevent the light emitted by the light source from passing through when the light source is lit. Thus, it can be understood that the elements located behind the transparent or translucent component are prevented from affecting the aesthetics of the vehicle because these elements are blocked by the paint layer.

[0012] Advantageously, the paint layer is a synthetic paint layer.

[0013] ″Synthetic paint″ refers to a paint having a hardener. As an implementation example, the synthetic paint can be made based on a thermosetting resin, especially an alkyd resin or a glycerol phthalate resin, or based on polyurethane. Such synthetic paints can obtain a coloring rendering effect with a layer thickness much smaller than that required to obtain a rendering effect with conventional paints. It should be noted that the synthetic paint is an industrial synthetic paint, and in particular, it is not a natural gum resin, a natural resin, or a natural or synthetic varnish. Industrial synthetic paints are more durable than conventional paint series and do not require a protective varnish layer to be applied above them.

[0014] Advantageously, the paint layer comprises a transparent primer sub-layer. Advantageously, the synthetic paint layer comprises a transparent primer sub-layer.

[0015] Advantageously, the laser radiation has the following parameters: a wavelength in the infrared, an operating frequency between 5 and 10 W, a scanning speed between 1800 and 2200 mm / s, and a pulse frequency between 25000 and 35000 Hz.

[0016] Thereby, it is possible to etch the paint layer, in a part of its thickness, in a particularly controlled and reproducible manner.

[0017] Advantageously, after local irradiation, the paint layer has a thickness between 1 and 8 μm in a predetermined pattern.

[0018] Such a thickness corresponds to a good compromise between the residual transmission of light through the paint layer in the pattern area and hiding the light source when the light source is turned off.

[0019] Advantageously, the transparent or translucent part is made by molding a plastic material such as polycarbonate (PC), polypropylene (PP), polyamide (PA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyurethane (PU), polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene (ABS), styrene-acrylonitrile (SAN), acrylonitrile-styrene-acrylate (ASA), polymethyl methacrylate (PMMA), cycloolefin copolymer (COC) or cycloolefin polymer (COP).

[0020] Thereby, the transparent or translucent part is easy to manufacture and not costly.

[0021] Advantageously, the paint layer is opaque, preferably black or grey.

[0022] The opacity of the paint or synthetic paint makes it possible to improve the lighting quality of the pattern produced by a light source arranged behind the vehicle part, thus preventing the formation of a blurred halo at the edges of the pattern.

[0023] Advantageously, the light source is mounted opposite the paint layer.

[0024] Thereby, the paint layer is intended to face the interior of the vehicle when the vehicle part is mounted in the vehicle. It is thus no longer necessary to protect the paint layer from external aggressions such as mechanical stress or ultraviolet radiation from the sun.

[0025] According to the invention, there is also provided a vehicle part comprising a transparent or translucent part on which a paint layer is applied, the paint layer having a first thickness in a predetermined pattern and a second thickness outside the predetermined pattern, the first thickness being less than the second thickness.

[0026] Advantageously, the haze coefficient, or Haze coefficient, of the vehicle component in a predetermined pattern is greater than or equal to 60%, preferably greater than or equal to 75%, for example approximately equal to 80%, and more preferably greater than or equal to 90%.

[0027] Advantageously, the transparency of the vehicle component in a predetermined pattern is greater than or equal to 20%, preferably greater than or equal to 30%, and more preferably between 35% and 45%.

[0028] These values correspond to a good compromise between the transmission of light through the paint layer in the pattern area and hiding the light source when the light source is turned off.

[0029] Advantageously, the vehicle component further includes a light source mounted opposite the paint layer. The transparent or translucent component is intended to protect the light source while allowing the light emitted by the light source to pass through locally. Description of the Drawings

[0030] The present invention will be better understood by reading the following description, given by way of example only, with reference to the accompanying drawings:

[0031] Figure 1 is a cross-sectional view of the first implementation step of a method for manufacturing a vehicle component according to an embodiment of the present invention;

[0032] Figure 2 is a cross-sectional view of the second implementation step of a method for manufacturing a vehicle component according to an embodiment of the present invention; and

[0033] Figure 3 is a cross-sectional view of the third implementation step of a method for manufacturing a vehicle component according to an embodiment of the present invention. Detailed Description of the Invention

[0034] Figure 1 Illustrates the first step of a method for manufacturing a vehicle component 2 according to an embodiment of the present invention.

[0035] ​​​The vehicle component 2 includes a transparent or translucent component 4 intended to protect a light source. "Transparent" and "translucent" mean that they are respectively transparent and translucent at least for light radiation with wavelengths in the visible spectrum (i.e., 380 to 780 nm). The component 4 is here transparent and is made of a plastic material with this characteristic, which is in this example polycarbonate, commonly referred to as "PC". However, it can be provided to be made of any other plastic, such as polypropylene (PP), polyamide (PA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyurethane (PU), polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), styrene acrylonitrile (SAN), acrylonitrile styrene acrylate (ASA), polymethyl methacrylate (PMMA), cycloolefin copolymer (COC) or cycloolefin polymer (COP). The transparent or translucent component 4 is made by molding. Such methods are known and will not be further described hereinafter.

[0036] The vehicle component 2 includes a paint layer 6 applied (deposited) on the first face of the transparent or translucent component 4, which first face is intended to face the interior of the vehicle when the vehicle component 2 is installed on the vehicle. The paint layer 6 is single-layered, i.e., a single product is applied on the component to achieve the paint layer, and the paint is deposited by a single application. The paint layer is here a synthetic paint layer 6, but the present invention can be implemented with a so-called "conventional" paint layer. "Synthetic paint" means a paint with a curing agent. As an example, the synthetic paint can be made of a thermosetting resin, especially alkyd resin or glycerol phthalate resin, or made of polyurethane. It should be noted that the said synthetic paint is a synthetic paint for industrial use and is in particular not a natural gum resin, natural resin or natural or synthetic varnish. Here, the synthetic paint layer 6 is opaque. Preferably, it is black or grey. The synthetic paint layer 6 has a thickness approximately equal to 25 μm. Optionally, a transparent primer sub-layer is deposited below the synthetic paint layer 6, and in the applicable case, the thickness of the transparent primer sub-layer is 25 to 30 μm.

[0037] The vehicle component 2 includes a varnish layer 8, which is applied on the second face of the transparent or translucent component 4 opposite to the first face. In other words, the varnish layer 8 and the paint layer 6 are applied on opposite faces of the transparent or translucent component 4. The varnish layer 8 can protect the transparent or translucent component 4 from any ultraviolet radiation (especially from the sun) to which it may be exposed. This is particularly advantageous if the transparent or translucent component 4 is made of polycarbonate.

[0038] According to the first step of the method for manufacturing the vehicle component 2, the varnish layer 8 and the synthetic paint layer 6 are applied (deposited) on the transparent or translucent component 4. The thickness of the synthetic paint layer 6 is sufficient for it to completely absorb all light beams in the visible spectrum. This thickness is here 25 to 50 μm.

[0039] Figure 2 Shows the second step after the first step of the method for manufacturing a vehicle component 2. In this second step, a part of the vehicle component 2 is irradiated with laser radiation 10 to etch the synthetic paint layer 6. This operation is commonly referred to as "laser-etching" (English term), which is translated as "laser etching". The laser radiation 10 has the following parameters: a wavelength included in the infrared range, an operating power between 5 and 10 W, a scanning speed between 1800 and 2200 mm / s, and a pulse frequency between 25000 and 35000 Hz. As an example, the laser radiation 10 here has the following parameters: a wavelength equal to 1064 nm; an operating power equal to 8 W; a scanning speed equal to 2000 mm / s; a pulse frequency equal to 30000 Hz. By irradiating the synthetic paint layer 6 in the combustion pattern area with the laser radiation 10, only the combustion residues of the layer are retained, and the parameters of the laser radiation are set to achieve this result. In the pattern area, the residues partially migrate into the transparent or translucent component 4, forming a thin residual synthetic paint layer. It is not dense (compact), not homogeneous (uniform), and has a sparse granular appearance, such that it transmits light in a scattered (diffuse) manner.

[0040] The irradiation is carried out only in a part of the vehicle component 2, that is, according to a predetermined pattern formed on the synthetic paint layer 6. The irradiation is controlled such that the synthetic paint layer 6 is irradiated only in a part of its thickness within the pattern, and not the transparent or translucent component 4. If there is a transparent primer sublayer, the transparent primer sublayer can protect the transparent or translucent component 4 from the heat effect of the laser radiation 10 by creating a separation distance between the irradiated synthetic paint layer 6 and the transparent or translucent component 4. In fact, in the absence of a primer sublayer, it is observed that under the action of the laser radiation 10, the transparent or translucent component 4 tends to turn yellow, especially if it is made of polycarbonate.

[0041] After irradiation, the synthetic paint layer 6 has two levels.

[0042] In the predetermined pattern area, the synthetic paint layer 6 exists with a first thickness equal to a proportion of its original thickness, and this first thickness is between 1 and 8 μm here. Thus, it is the single layer itself that forms the synthetic paint layer 6 that is etched. In this area, the vehicle component 2 has a haze coefficient (which is more often referred to as the "Haze coefficient" in English) greater than or equal to 60%, preferably greater than or equal to 75%, preferably greater than 90%, and a transparency greater than or equal to 20%, preferably greater than or equal to 30%, more preferably between 35% and 45% (ideally equal to 40%).

[0043] Outside the predefined pattern area, the synthetic paint layer 6 is intact and has a second thickness equal to the applied deposition thickness of the synthetic paint layer 6. Thus, the first thickness is less than the second thickness.

[0044] After the irradiation step, an additional step of polishing the transparent or translucent component 4 may be provided. It allows improving the transparency in the predefined pattern area and, more generally, the aesthetics of the vehicle component 2. In addition, this polishing can round the corners formed by the etching carried out during the irradiation step and thus reduce the light scattering phenomenon that would interfere with the light beam passing through the vehicle component 2.

[0045] Figure 3 A third step of a method for manufacturing the vehicle component 2 is shown. In this step, which occurs after the irradiation step, the light source 12 is combined with the transparent or translucent component 4. Here, the light source 12 is mounted facing the synthetic paint layer 6 such that when the vehicle component 2 is installed in the vehicle, the synthetic paint layer faces the interior of the vehicle. In other words, the synthetic paint layer 6 is deposited on the face (first face) of the transparent or translucent component 4 that is opposite to the face (second face) of the transparent or translucent component 4 that is visible from the outside when the vehicle component 2 is installed in the vehicle. When referring to this arrangement, it is generally stated in English that the synthetic paint layer 6 is located on the B side (B face). The varnish layer 8 is then applied on the A side (A face). Thus, the above-mentioned first face and second face correspond to the B face and A face respectively.

[0046] When the light source 12 is turned off, it does not emit light; due to the presence of the synthetic paint layer 6, which exists in its entire thickness outside the pattern area and in its partial thickness in the pattern area, the light source is not visible through the transparent or translucent component 4.

[0047] When the light source 12 is lit so that it emits light towards the transparent or translucent component 4, the light partially passes through the synthetic paint layer 6 in the pattern area and is blocked by the synthetic paint layer 6 outside the pattern area. Since the synthetic paint layer 6 is opaque and black or grey in color, it does not change or does not significantly change the color of the light that passes through it, and the transmitted light does not form a blurred halo at the edges of the pattern area.

[0048] The present invention is not limited to the illustrated factual manner, and other embodiments will be apparent to those skilled in the art.

[0049] The light source can be an optical unit for the low beam and high beam lights of a vehicle, an optical unit for the turn signal lights of a vehicle, or even a part of an optical unit for decorative lights.

[0050] The paint or synthetic paint can be made of a coloring material. Thus, the scattering of the light emitted by the light source through the partial synthetic paint layer is accompanied by the coloring of the light, which gives it a certain aesthetic effect.

[0051] Alternative embodiments can be provided, in which a paint layer or a synthetic paint layer is applied and deposited on the A side of a transparent or translucent component. In this case, a varnish layer is applied and deposited above the paint layer or the synthetic paint layer, and the B side of the transparent or translucent component can be left exposed, with a light source arranged in front of this B side.

[0052] List of reference numerals

[0053] 2: Vehicle component

[0054] 4: Transparent or translucent component

[0055] 6: Paint layer / Synthetic paint layer

[0056] 8: Varnish layer

[0057] 10: Laser radiation

[0058] 12: Light source

Claims

1. A method for producing a vehicle component (2), characterized in that The method comprises the following steps: - applying a paint layer (6) on one side of the transparent or translucent component (4), the paint layer (6) being a single layer; and - locally irradiating the lacquer layer (6) with laser radiation (10) in order to etch the lacquer layer (6) in a portion of its thickness according to a predetermined pattern.

2. The method of claim 1, wherein: The paint layer (6) is a synthetic paint layer.

3. A method as claimed in any one of the preceding claims, wherein: The laser radiation (10) has the following parameters: wavelength in the infrared, operating frequency between 5 and 10 W, scanning speed between 1800 and 2200 mm / s, and pulse frequency between 25000 and 35000 Hz.

4. A method as claimed in any one of the preceding claims, wherein: After the local irradiation, the paint layer (6) has a thickness of 1 to 8 μm in the predetermined pattern.

5. A method as claimed in any one of the preceding claims, wherein: The transparent or translucent component (4) is manufactured by molding a plastic material such as polycarbonate, polypropylene, polyamide, polyethylene terephthalate, polybutylene terephthalate, polyurethane, polyvinyl chloride, propylene styrene butadiene, styrene acrylonitrile, acrylonitrile styrene acrylate, polymethyl methacrylate, cycloolefin copolymer or cycloolefin polymer.

6. A method as claimed in any one of the preceding claims, wherein: The paint layer (6) is opaque, preferably black or grey.

7. A method as claimed in any one of the preceding claims, wherein: A light source (12) is mounted opposite the paint layer (6).

8. A vehicle component (2), characterized in that The vehicle component comprises a transparent or translucent component (4) on which a paint layer (6) is applied, the paint layer having a first thickness in a predetermined pattern and a second thickness outside the predetermined pattern, the first thickness being smaller than the second thickness.

9. The vehicle component (2) according to claim 8, wherein: The haze factor, or Haze coefficient, of the vehicle component in the predetermined pattern is greater than or equal to 60%, preferably greater than or equal to 75%, more preferably greater than or equal to 90%.

10. The vehicle component (2) according to claim 8 or 9, wherein: The transparency of the vehicle component in the predetermined pattern is greater than or equal to 20%, preferably greater than or equal to 30%, more preferably between 35% and 45%.

11. The vehicle component (2) according to any one of claims 8 to 10, further comprising a light source (12) mounted opposite the paint layer (6).

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