Painted body parts comprising a decorative pattern in hot stamping

Abstract

The invention relates to a body part (10) of a motor vehicle comprising at least one wall (20) made of plastic material, characterized in that said wall (20) is at least partially covered with a colored film (30) comprising a decorative pattern (40) cut in the entire thickness of the colored film (30), the plastic material not covered by the colored film (30) at the decorative pattern (40) comprising a decorative element (50).

Description

Technical Field

[0001] This invention relates to the field of motor vehicles, and more specifically, to the field of body parts made of plastic, such as front or rear bumpers, roofs, tailgate-type closures, trunks or doors, grilles, and radiator grilles.

[0002] Specifically, the present invention relates to a vehicle body part including decorative elements, and a method for manufacturing such a part. Background Technology

[0003] It is often necessary to improve the aesthetic appearance of vehicle body parts to make them more attractive to consumers or to differentiate them from competitors. Various methods are known, such as painting, applying adhesive decorative films, and printing patterns, for example by hot stamping (or hot stamping, marquage à chaud). Hot stamping is a printing method that uses a hot die (hot stamping die) to apply a decorative film to the surface of a part. An example of a method and apparatus for printing patterns by hot stamping is described in document US 2017 / 326860.

[0004] However, current hot stamping technology cannot be applied to plastic parts that have already undergone a painting process. In fact, the paint layer is a combination of primer, color paint, and clear coat, which cannot effectively and repeatedly fix the decorative film applied by hot stamping.

[0005] Different solutions can be considered to obtain the outer surface of body parts, including painted areas with decorative films applied by hot stamping.

[0006] For example, a masking operation can be performed before painting the aforementioned areas to ensure that the areas receiving the decorative film are free of paint. However, this technique may result in defects at the boundary between the painted area and the decorative film applied by hot stamping.

[0007] Another solution considered is to scrape off the paint, for example, using a laser scraper, so that the plastic material comes into direct contact with the hot stamping die. However, this technique is unsatisfactory because the scraped surface has roughness, which results in an unacceptable appearance after the decorative film is applied by hot stamping. Moreover, the boundary between the painted area and the decorative film applied by hot stamping also has unacceptable defects in terms of perceived quality, because the decorative film applied locally to the laser-scraped area is difficult to precisely cover the entire scraped area, and gaps may exist between the painted area and the area covered by the decorative film on the part.

[0008] This problem associated with hot stamping may also be encountered in other processes that do not apply decorative films to painted surfaces, such as pad printing. Summary of the Invention

[0009] The object of the present invention is particularly to overcome these defects by providing a vehicle body part made of plastic material, wherein a colored film is used instead of paint, and this colored film is cut along its entire thickness to form a decorative pattern. Thus, the demarcation of the decorative pattern area is clear, and by means of the cutting of the colored film, there is no need to worry about defects at the boundary. Moreover, the decorative film is applied to the pattern area by, for example, hot stamping, not on paint or on the colored film, but on the plastic material of the cut area of ​​the colored film on the vehicle body part.

[0010] For this purpose, the subject of the invention is a body part of a motor vehicle comprising at least one wall made of a plastic material, wherein the wall is at least partially covered by a colored film comprising decorative patterns cut along the entire thickness of the colored film, and the plastic not covered by the colored film at the decorative patterns comprising decorative elements.

[0011] Therefore, the body part includes a decorative pattern covered by decorative elements that can be applied using a hot stamping process. Moreover, the pattern can be easily changed between different vehicles because the pattern can be reshaped for body parts of the same shape.

[0012] Finally, even after hot stamping, such parts have good visual quality in the boundary area between the colored film and the decorative pattern. This is because the hot stamping die can be adjusted to cover the entire surface of the decorative pattern well, thus avoiding any free space between the colored area (colored film) and the applied decorative film.

[0013] The present invention is also suitable for large-sized vehicle body parts, such as bumpers, fenders, and tailgate covers, and generally suitable for parts with a maximum dimension of 1 m and / or an area of ​​0.5 m2.

[0014] According to the present invention, the part may, individually or in combination, incorporate the following optional features: - Decorative elements are decorative films applied using a hot stamping process; - Colored film has the color of the car body and covers the wall in unpainted areas; - A colored film is molded onto the wall; - The plastic material forming the wall is flush with the free surface of the colored film at the decorative pattern; - The plastic material forming the wall protrudes from the free surface of the colored film at the decorative pattern; - The colored film is made alone or in combination of materials selected from the following: polycarbonate, polyetherimide, polyethersulfone and polymethyl methacrylate, thermoplastic polyolefin, thermoplastic polyurethane, acrylonitrile butadiene styrene, polyvinyl chloride, polypropylene, polyamide, polycarbonate-polyethylene, polyethylene and acrylonitrile butadiene styrene-polycarbonate. - The thickness of the colored film is between 0.1 and 3 mm.

[0015] The present invention also relates to a method for manufacturing body parts of a motor vehicle as described above, wherein the following steps are performed: - Cut decorative patterns into colored films; - Apply a colored film to the wall of the mold cavity; - Close the mold and inject plastic material into the mold cavity to cover the molded walls on the colored film; - Remove the car body parts from the mold; and - Decorative elements are applied locally on the wall, in areas with decorative patterns.

[0016] This method can, for example, achieve a chrome finish on large plastic parts that are painted in the same color as the car body.

[0017] Moreover, this method does not necessarily require an undulating portion in the mold, thus allowing the use of a smooth die. Consequently, the same die can be used for both conventionally painted parts (without patterns) and patterned parts (the die must still allow for the placement of the film to be molded).

[0018] According to this method, the following optional features can be used individually or in combination: * Decorative elements are decorative films applied using a hot stamping process; * Implement the following steps sequentially: - Cut decorative patterns into colored films; - Apply a colored film to the wall of the cavity of the mold; - Close the mold and inject plastic material into the mold cavity to cover the molded walls on the colored film; - Remove the car body parts from the mold; and - A decorative film is applied locally to the wall, specifically to the decorative pattern area, using a hot stamping process.

[0019] * Implement the following steps sequentially: - On the colored film, at least in the area where the decorative pattern should be received, a peelable film is arranged; - Cut decorative patterns in colored and peelable films; - Apply a colored film covered with a peelable film to the wall of the cavity of the mold, the peelable film being arranged to adhere to the cavity. - Close the mold and inject plastic material into the mold cavity to cover the molded walls on the colored film; - Remove the car body parts from the mold; - Remove the peelable film from the surface of the colored film; and - A decorative film is applied locally to the wall, specifically to the decorative pattern area, using a hot stamping process.

[0020] * Implement the following steps sequentially: - Apply a colored film to the wall of the cavity of the mold; - Close the mold and inject plastic material into the mold cavity to cover the molded walls on the colored film; - Remove the car body parts from the mold; - Cutting decorative patterns into colored films; and - A decorative film is applied locally to the wall, specifically to the decorative pattern area, using a hot stamping process. Attached Figure Description

[0021] A better understanding of the invention will be achieved by reading the following description, provided only as an example, with reference to the accompanying drawings, in which: Figure 1 An example of a vehicle body part according to the invention is shown, which includes a wall with a decorative pattern.

[0022] Figure 2 The image shows a detailed section of the wall of an example body part at the pattern, showing the overlay of the wall and membrane, and the cutting of the membrane to form a decorative pattern and give way to the wall made of plastic.

[0023] Figure 3 is a series of diagrams illustrating manufacturing steps of an example of a first embodiment of a vehicle body part according to the present invention. Figures 3A to 3D ).

[0024] Figure 4 is a series of diagrams illustrating an example of the manufacturing steps of a first variant of a second embodiment of a body part according to the present invention. Figures 4A to 4E ).

[0025] Figure 5 is a series of diagrams illustrating an example of the manufacturing steps of a second variant of a second embodiment of a vehicle body part according to the present invention. Figures 5A to 5D ).

[0026] Figure 6 is a series of diagrams illustrating an example of the manufacturing steps of a third variant of a second embodiment of a vehicle body part according to the present invention. Figures 6A to 6E ). Detailed Implementation

[0027] Figure 1The diagram shows a body part 10 of a motor vehicle including an unpainted wall 20, which has an exterior surface visible from the outside of the vehicle. The wall 20 is preferably made of plastic using an injection molding process, and it includes decorative patterns 40 on its exterior surface. Figure 1 In the example, there are two sequences of four patterns.

[0028] Figure 2 A detailed cross-sectional view of a portion of the wall 20 at the decorative pattern 40, according to one embodiment of the body part 10, is shown.

[0029] like Figure 2 As shown, wall 20 is covered with a colored film 30. This colored film advantageously has the color of a "car body" to replace the paint that would otherwise be applied to the plastic of wall 20. Thus, the colored film 30 covers the unpainted areas of wall 20.

[0030] The colored film 30 is advantageously made of materials selected alone or in combination from the following: polycarbonate (PC), polyetherimide (PEI), polyethersulfone (PES) and polymethyl methacrylate (PMMA), thermoplastic polyolefin (TPO), thermoplastic polyurethane (TPU), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), polypropylene (PP), polyamide (PA), polycarbonate-polyethylene (PC / PET), polyethylene (PET) and acrylonitrile butadiene styrene-polycarbonate (ABS / PC).

[0031] The thickness of the colored film 30 is preferably 0.1 to 3 mm.

[0032] Advantageously, the colored film 30 is applied to the wall 20 by overmolding through injection molding.

[0033] like Figure 2 As shown, according to the present invention, the colored film 30 includes at least one decorative pattern 40, which is cut to extend through the entire thickness of the colored film 30. The decorative pattern 40 can have any shape, which may include, for example, curves, geometric shapes (e.g., ovals, rectangles, triangles), or even logos or text.

[0034] Since the decorative pattern 40 is cut out over the entire thickness of the colored film 30, the plastic material of the wall 20 is not covered by the colored film 30 at the decorative pattern 40.

[0035] According to the invention, the decorative pattern 40 advantageously covers the decorative element 50, for example, a decorative film applied by hot stamping. In fact, hot stamping (thermal stamping) technology is very suitable for applying localized decorative films to surfaces produced by injection molding of plastic materials.

[0036] Three implementation methods in Figure 2 ,3D As shown in 4E, 5D and 6E, and described below.

[0037] According to the first embodiment ( Figure 2 and 3D The plastic material forming the wall 20 is flush with the free surface of the colored film 30 (i.e., the surface that does not contact the wall 20—this is the surface located on the "outer side" of the vehicle) in the area of ​​the decorative pattern 40. The plastic material of the wall 20 thus forms a protrusion in the area of ​​the decorative pattern 40.

[0038] According to the second embodiment ( Figure 4E and 5D The plastic material forming the wall 20 protrudes from the free surface of the colored film 30 (without contacting the wall 20) in the area of ​​the decorative pattern 40. This is particularly advantageous for preventing the die (punch) 110 of the hot stamping equipment from contacting the colored film 30 during production. In fact, such contact would damage the colored film 30 and result in a decrease in the perceived quality of the body part 10.

[0039] According to the third embodiment ( Figure 6E The plastic material forming the wall 20 is flush with the non-free surface (the surface in contact with the wall 20) of the colored film 30. Therefore, at the decorative pattern 40, there is no plastic material within the thickness of the colored film 30.

[0040] The present invention also relates to a method for manufacturing a body part 10 of a motor vehicle according to the present invention.

[0041] The method according to the present invention includes the following steps: - Cut decorative patterns 40 in the colored film 30; - A colored film 30 is applied to the wall of the mold cavity, which is preferably smooth; - Close the mold and inject the plastic material into the mold cavity to cover the molding wall 20 on the colored film 30; - Remove body parts 10 from the mold; and - On the wall 20, at the location of the decorative pattern 40, decorative elements 50 are applied locally.

[0042] According to a preferred embodiment, after the body part 10 is removed from the mold, a hot stamping step is performed on the body part 10 in the area of ​​the decorative pattern 40 to apply a decorative film (decorative element 50) directly on the wall 20 at the location of the decorative pattern 40.

[0043] Three implementations are shown in Figures 3, 4, 5 and 6, and are described below.

[0044] According to the first embodiment (Figure 3), the method includes the following successive steps: i- Cut decorative patterns 40 in the colored film 30; ii- Apply a colored film 30 to the wall of the cavity 100 of the injection mold. Figure 3A The wall is preferably smooth; iii- Close the mold and inject plastic material into the mold cavity to cover the molded wall 20 on the colored film 30. Figure 3B ); iv- Remove body parts 10 from the mold ( Figure 3C );and v- A decorative film is applied locally on the wall 20 at the decorative pattern 40 using a hot stamping process.

[0045] The body parts thus include decorative patterns covered with decorative elements that can be applied using a hot stamping process. Moreover, the patterns can be easily changed between vehicles because the patterns can be varied for the same body part shape.

[0046] As shown in Figure 3, even after hot stamping, such parts have good visual quality in the boundary area between the colored film and the decorative pattern. This is because the adjustable die (punch) can cover the entire surface of the decorative pattern well, so as to avoid any free space between the colored area (colored film) and the applied decorative film.

[0047] According to a first variant of the second embodiment (Figure 4), the method includes the following successive steps: i- On the colored film 30, at least in the area where the decorative pattern 40 should be received, a peelable film 60 (temporary film) is arranged. ii- Decorative patterns 40 are cut into the colored film 30 and the peelable film 60, that is, throughout the entire thickness of the two films 30 and 60; iii- A colored film 30 covered with a peelable film 60 is applied to the wall of the cavity 100 of the injection mold, the wall preferably being smooth, the peelable film 60 being arranged to adhere to the cavity 100. Figure 4A ); iv- Close the mold and inject plastic material into the mold cavity to cover the molded wall 20 on the colored film 30. Figure 4B ).

[0048] v- Remove body parts 10 from the mold ( Figure 4C ); vi- Remove the peelable film 60 from the surface of the colored film 30 ( Figure 4D );and vii- By hot stamping, a decorative film is applied locally on the wall 20 at the decorative pattern 40. Figure 4E ).

[0049] Using this method, the plastic material forming the wall 20 protrudes from the free surface of the colored film 30 (without contacting the wall 20) in the area of ​​the decorative pattern 40. Thus, the decorative pattern 40 is raised relative to the colored film 30. This is particularly advantageous for the stamping die 110 of the hot stamping equipment to avoid contact with the colored film 30 during the hot stamping step. In practice, such a die typically includes cutting elements around its perimeter that could damage the colored film 30 and reduce the perceived quality of the body part 10 (see...). Figure 4E ).

[0050] The peelable film 60 has heat resistance strength higher than the melting temperature of the injected plastic material.

[0051] Furthermore, this variation does not require undulations in the mold, thus allowing the use of a smooth die. This allows the same die to be used for both conventionally painted parts (without patterns) and patterned parts.

[0052] According to a second variant of the second embodiment (Fig. 5), the mold used includes a cavity capable of molding a wall 20 having a thickened portion in the area to which the decorative pattern 40 should be received. Figure 5A The method includes the following sequential steps: i- Cut decorative patterns 40 in the colored film 30; ii- Apply a colored film 30 to the wall of the cavity 100 of the injection mold. Figure 5A ); iii- Close the mold, inject plastic material into the mold cavity to cover the molded wall 20 on the colored film 30, and have a thickened portion in the area where the decorative pattern 40 should be received ( Figure 5B ).

[0053] iv- Remove body parts 10 from the mold ( Figure 5C );and v- By hot stamping, a decorative film is applied locally on the wall 20 at the decorative pattern 40. Figure 5D ). Using the method described above, the plastic material forming the wall 20 protrudes from the free surface of the colored film 30 (without contacting the wall 20) in the area of ​​the decorative pattern 40. Thus, the decorative pattern 40 is raised relative to the colored film 30. This is particularly advantageous for the stamping die 110 of the hot stamping equipment to avoid contact with the colored film 30 during the hot stamping step. In practice, such a die typically includes cutting elements around its perimeter that could damage the colored film 30 and reduce the perceived quality of the body part 10 (see...). Figure 4E ).

[0054] This variant avoids the use of peelable film 60 and the resulting manufacturing steps and material costs.

[0055] According to the third embodiment (Figure 6), the method includes the following successive steps: i- Apply a colored film 30 to the wall of the cavity 100 of the injection mold. Figure 6A The wall is preferably smooth; ii- Close the mold and inject plastic material into the mold cavity to cover the molded wall 20 on the colored film 30. Figure 6B ).

[0056] iii- Remove body parts 10 from the mold ( Figure 6C ); iv- Cut decorative patterns 40 in colored film 30 ( Figure 6D );and v- By hot stamping, a decorative film is applied locally on the wall 20 at the decorative pattern 40. Figure 6E ).

[0057] This implementation method facilitates the arrangement and positioning of the colored film on the wall 20.

[0058] In step iv, decorative patterns 40 can be cut into the colored film 30 by, for example, laser cutting.

[0059] This invention is not limited to the described embodiments, and other embodiments will be apparent to those skilled in the art. In the three embodiments, it is particularly feasible to use techniques other than hot stamping to apply other types of decorative elements 50.

[0060] List of reference numerals 10: Vehicle body parts 20: Wall of body part 10 (from plastic material injection) 30: Colored film 40: Decorative patterns on a colored film, cut across the entire thickness of the colored film 30. 50: Decorative elements, such as decorative films applied by hot stamping. 60: A temporary / peelable film disposed on a colored film, which adheres to the wall of the die cavity 100 of the mold during the manufacturing process. 70: Boundary area between decorative element 50 and colored film 30 100: Cavity of injection mold 110: The die for hot stamping equipment.

Claims

1. A body part (10) of a motor vehicle, comprising at least one wall (20) made of plastic material, characterized in that, The wall (20) is at least partially covered by a colored film (30) comprising decorative patterns (40) cut throughout the thickness of the colored film (30), and the plastic material not covered by the colored film (30) at the decorative patterns (40) comprises decorative elements (50).

2. The vehicle body part (10) as claimed in claim 1, wherein, The decorative element (50) is a decorative film applied by a hot stamping process.

3. The vehicle body part (10) as described in claim 1 or 2, wherein, The colored film (30) has the color of the car body and covers the wall (20) in the unpainted area.

4. The vehicle body part (10) as described in claim 1 or 2, wherein, The colored film (30) is molded onto the wall (20).

5. The vehicle body part (10) as described in claim 1 or 2, wherein, The plastic material forming the wall (20) is flush with the free surface of the colored film (30) at the decorative pattern (40).

6. The vehicle body part (10) as claimed in claim 1 or 2, wherein, The plastic material forming the wall (20) protrudes from the free surface of the colored film (30) at the decorative pattern (40).

7. The vehicle body part (10) as claimed in claim 1 or 2, wherein, The colored film (30) is made of materials selected alone or in combination from the following: polycarbonate (PC), polyetherimide (PEI), polyethersulfone (PES) and polymethyl methacrylate (PMMA), thermoplastic polyolefin (TPO), thermoplastic polyurethane (TPU), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), polypropylene (PP), polyamide (PA), polycarbonate-polyethylene (PC / PE), and polyethylene (PE).

8. The vehicle body part (10) as claimed in claim 1 or 2, wherein, The thickness of the colored film (30) is between 0.1 and 3 mm.

9. A method for manufacturing a body part (10) of a motor vehicle as described in any one of claims 1-8, characterized in that, Implement the following steps: - Cut decorative patterns (40) in the colored film (30); - Apply the colored film (30) to the wall of the mold cavity; - Close the mold and inject plastic material into the mold cavity to cover the molded wall (20) on the colored film (30). - Remove the body part (10) from the mold; and - Decorative elements (50) are applied locally on the wall (20) at the decorative pattern (40).

10. The method of claim 9, wherein, The decorative element (50) is a decorative film applied by a hot stamping process.

11. The method of any one of claims 9 and 10, wherein, The following steps will be implemented successively: - Cut the decorative pattern (40) in the colored film (30); - Apply the colored film (30) to the wall of the cavity (100) of the mold. - Close the mold and inject plastic material into the mold cavity of the mold to cover the molded wall (20) on the colored film (30). - Remove the body part (10) from the mold; and - A decorative film is applied locally on the wall (20) at the decorative pattern (40) by hot stamping process.

12. The method of any one of claims 9 and 10, wherein, The following steps will be implemented successively: - On the colored film (30), at least in the area where the decorative pattern (40) should be received, a peelable film (60) is arranged. - Cut the decorative pattern (40) in the colored film (30) and the peelable film (60); - Apply the colored film (30) covered with the peelable film (60) to the wall of the cavity (100) of the mold, the peelable film (60) being arranged to abut against the cavity (100). - Close the mold and inject plastic material into the mold cavity to cover the molded wall (20) on the colored film (30). - Remove the body part (10) from the mold; - Remove the peelable film (60) from the surface of the colored film (30); and - A decorative film is applied locally on the wall (20) at the decorative pattern (40) by hot stamping process.

13. The method of any one of claims 9 and 10, wherein, The following steps will be implemented successively: - Apply the colored film (30) to the wall of the cavity (100) of the mold. - Close the mold and inject plastic material into the mold cavity to cover the molded wall (20) on the colored film (30). - Remove the body part (10) from the mold; - Cut the decorative pattern (40) in the colored film (30); and - A decorative film is applied locally on the wall (20) at the decorative pattern (40) by hot stamping process.

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