Method for manufacturing decorative parts for vehicle interiors

Abstract

SOLUTION: A method for manufacturing a decorative component for a vehicle interior, comprising a base material and a decorative layer applied to the base material, where the front side of the decorative layer forms a visible side of the decorative component. The method includes the steps of: providing a base film; forming a composite layer by applying a decorative layer to a first surface of the base film; micro-perforating the decorative layer in one or more areas or over an entire surface; inserting or retracting the composite layer consisting of the base film and the micro-perforated decorative layer into a cavity of an injection mold so that the decorative layer of the composite layer is back-injected and a second side of the base film is pressed against the cavity wall; closing the cavity, injecting a plastic material into the cavity and back-injecting it into the decorative layer during formation of the base material in the cavity, so that the decorative layer is attached to a surface of the base material facing the decorative layer, forming a decorating layer of the decorative component; and opening the cavity to remove or eject decorative component.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a decorative part for a vehicle interior. The decorative part to be manufactured comprises a substrate and a decorative layer applied to the substrate, the front side of the decorative layer opposite the substrate forming the visible side of the decorative part. [Background technology]

[0002] In general, when designing the interior of an automobile, a seamless and smooth design surface is desired. Therefore, it is desired that the necessary operating elements and / or display elements and / or lighting elements and other components are functionally integrated in the decorative parts. Therefore, it is desirable to integrate, for example, operating functions and / or information functions and / or lighting functions on the visible side of the decorative parts, and replace independent components for these functions. In order to meet the requirement of a seamless and smooth design surface, it is necessary to design these functions to be integrated into the decorative parts so that they are not visible when they are not in use. That is, when they are not in use, the design surface should be visible to the viewer on the visible side of the decorative parts, and the seamless and smooth design surface should be visible to the viewer. Functions or functional parts should only be visible when they are in use, i.e., when they are active. On the other hand, in the inactive state, functions and functional parts such as switches, buttons, and display devices should be invisible. In this case, the visible side of the decorative part is not obstructed by these, and the viewer sees a seamless, consistent, and smooth design.

[0003] For example, it is known to integrate displays into decorative parts for vehicle interiors. These displays appear as black or dark areas when not in use because the display area is integrated into the visible side of the decorative part. These black or dark areas stand out from the rest of the design of the decorative part and are perceived as unattractive. There is therefore a desire to have the display or the display area of ​​the display on the visible side of the decorative part only visible when the display is switched on and displaying in the display area. Summary of the Invention

[0004] The object of the present invention is to provide a new method for producing decorative parts, in particular a method for producing decorative parts that meets the aforementioned requirements, which should preferably allow for a simple and / or cost-effective production of the decorative parts.

[0005] This object is achieved by a method comprising the features of claim 1. Advantageous embodiments and further developments are defined in the dependent claims. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] The method according to the invention is provided for producing a decorative part for a vehicle interior, the decorative part comprising a substrate and a decorative layer applied to the substrate, the front side of the decorative layer opposite the substrate forming the visible side of the decorative part.

[0007] The method according to the invention comprises the following steps. a) providing a substrate film; b) forming a composite layer by applying a decorative layer to a first surface of a substrate film; c) microperforating the decorative layer in one or more areas or over the entire surface; d) inserting or withdrawing the composite layer composed of the substrate film and the micro-perforated decorative layer into the cavity of the injection mold, such that when the plastic material is injected into the cavity, the decorative layer of the composite layer is back-injected and the second side of the substrate film opposite to the first side is pressed against the wall of the cavity; e) closing the cavity and injecting a plastic material into the cavity to form a substrate of the decorative part, and during the formation of the substrate in the cavity, back-injecting the decorative layer to apply the decorative layer to the surface of the substrate facing the decorative layer, thereby forming a decorative layer of the decorative part; f) Opening the cavity and removing or ejecting the decorative parts.

[0008] The pressure of the plastic material injected in step e) presses the substrate film against the wall of the cavity. The decorative layer, e.g. a lacquer coat, is adhered to the injected plastic material by the temperature and / or pressure of this plastic material. At the same time, the pressure layer can be peeled off from the substrate film, but this is not necessary.

[0009] Microperforation is understood as meaning the introduction of a large number of through holes in the decorative layer. In the area of ​​the holes, the decorative layer has been removed. The cross-sectional dimensions of these holes are, for example, in the range of 50-150 μm, for example 90 μm. All holes may be evenly arranged in the microperforated area. In this case, the density of the holes is constant. Also, all holes may have the same cross-sectional shape and the same dimensions. As a cross-sectional shape, for example, a circle is conceivable. Thus, for example, circular holes may be evenly distributed in the microperforated area of ​​the decorative layer. The diameter of the holes is preferably selected so that, when viewed normally without aids and backlighting, the holes on the visible side are not visible to the viewer, that is, the viewer only sees a uniform, continuous, seamless design. For example, the disruption of the design due to the display of the display device is only visible when the holes are backlit. For typical holes with a diameter in the range of 50-150 μm, the spacing between the holes is typically in the range of 60-160 μm. Such microperforations have a resolution in the range of 423-159 dpi. When the hole spacing is 100 μm, the resolution is 254 dpi. Also, small hole diameters of less than 50 μm, for example, hole diameters of 10 to 50 μm, are possible. In this case, the hole spacing may be, for example, 12 to 60 μm, and the resolution may be in the range of 2117 to 423 dpi.

[0010] Step f) may be followed directly or, if necessary, after further intermediate steps, by step g), which provides for removing the substrate film during or after removal or ejection of the decorative part from the cavity, with the decorative layer remaining on the substrate as a decorative layer, although alternatively the substrate film may remain on the decorative part.

[0011] If the method according to the invention is provided with the aforementioned step g), the substrate film may be a continuous film to which the decorative layer is applied either all over or in specific areas. In this case, in step d), the area of ​​the substrate film provided with the decorative layer is drawn into the cavity, for example by automatic feeding. In step g), the substrate film is peeled off from the decorative layer being produced when the decorative part is removed or ejected. Steps e), f) and g) can be carried out after the decorative part has been removed or ejected from the cavity, since the area of ​​the substrate film free of the decorative layer moves out of the cavity and at the same time, according to step d), another area of ​​the substrate film provided with the decorative layer enters the cavity. This sequence can be repeated many times, in particular in an automated manner.

[0012] It is also possible in step d) to insert an individual substrate film provided with a microperforated decorative layer into the cavity and then rear-inject according to step e). In this case, the substrate film may remain on the decorative part after ejection. However, it is also possible to remove the substrate film after removal or ejection of the decorative part according to the aforementioned step g). It is also possible to automate this process.

[0013] The above description shows that the production of microperforations in the decorative layer before it is applied to the substrate allows for a simple, efficient and therefore cost-effective method sequence in the production of decorative parts.

[0014] The application of the decorative layer to the substrate provided according to the present invention allows the preparation of the decorative layer, and thus the decorative layer, before the actual application by transferring the decorative layer applied to the substrate film. The decorative layer is micro-perforated on the substrate film. Since the micro-perforations are through holes, the irradiation of the laser to form the holes may cause damage to the substrate, such as the substrate becoming cloudy. The micro-perforation of the decorative layer on the substrate film may only damage the substrate film, which is not necessary for the production of the decorative part and is removed in any case.

[0015] The vanishing effect is also advantageous, i.e. the micro-perforated holes are invisible to the observer when they are not backlit. In this case, the visible side of the decorative part appears to the observer as a seamless, smooth, consistent design surface without defects. However, with backlighting, the operating and / or information and / or lighting functions integrated into the decorative part become visible. These functions can therefore be replaced by independent components.

[0016] A further development provides that the plastic material injected in step e) is a transparent plastic material and the formed substrate is a transparent substrate. This results in a decorative part having a relatively high transmittance. The clouding or other damage of the transparent substrate when microperforations are introduced is eliminated in the method according to the invention, because the microperforations are generated in a decorative layer prepared for this purpose on the substrate film before the decorative layer is applied to the substrate and are only transferred to the substrate afterwards. This eliminates a decrease in transmittance and / or a change in color rendering, which may occur if microperforations are formed in a decorative layer already applied to the substrate.

[0017] According to one embodiment of the present invention, the decorative part produced comprises a display device, which is attached, for example after step f) or step g), to the back side of the substrate opposite the decorative layer and / or in a recess in the substrate, such that the display area of ​​the display device faces the decorative layer and the display generated by the display area is thereby visible through the micro-perforations of the decorative layer on the visible side of the decorative part.

[0018] This allows the viewer to perceive the display generated by the display area on the visible side of the decorative part. In any case, the display is visible when the viewing angle is 90°, i.e. when the viewer of the decorative part looks vertically at the front side of the decorative part, and therefore parallel to the extension of the microperforations through the decorative layer.

[0019] In the case of oblique viewing angles, i.e. angles between 0° (parallel to the front surface of the decorative part) and 90° (perpendicular to the front surface of the decorative part), the visibility depends on the thickness of the decorative layer and the cross-sectional dimensions of the holes, i.e. in the case of circular holes, the diameter of the holes. The thinner the decorative layer with the same cross-sectional dimensions, the smaller the viewing angle at which the display is still visible to the viewer. Furthermore, the larger the cross-sectional dimensions of the decorative layer with the same thickness, the smaller the viewing angle at which the display is still visible to the viewer. However, in order to obtain a high resolution of the visualized display, the holes of the selected microperforations must be as small as possible. Therefore, for a certain hole diameter, the thickness of the decorative layer determines the possible oblique viewing angles. Starting from a direct view at a viewing angle of 90°, the smaller the viewing angle and therefore the more oblique the possible view of the display, the thinner the decorative layer. Thus, in the method according to the invention, a decorative part with microperforations covering the display surface of a display device, in which the display shown by the display device has a relatively low viewing angle dependence, i.e. starting from a perpendicular viewing angle on the front side of the decorative layer, the display becomes visible even at small viewing angles. As a result, the indicia can be seen and read at various positions in the vehicle. This visibility, i.e. either the smallest viewing angle at which the indicia is visible or the sharpest from the vertical, can be set by correspondingly selecting the conditions of the thickness of the decorative layer or decorative layer on the one hand and the diameter of the holes in the decorative layer or decorative layer on the other hand.

[0020] A further advantage of the method according to the invention is the pre-fabrication of micro-perforated holes on the substrate film, the edges of which are designed with a relatively high edge sharpness at the ends of the holes facing the substrate and / or the visible side, which provides a relatively precise and smooth visibility of the presentation or display to the viewer.

[0021] In connection with display devices, a further advantage of the microperforations of the decorative layer produced by means of the method according to the invention is the very good reproducibility of the brightness and color point of the display visible through the microperforations.

[0022] The advantage for the display device is that a lower brightness and cheaper superior display technology can be used, since the decorative layer on the substrate film is already micro-perforated, and the associated clouding and / or changes in color rendering of the transparent substrate are avoided. Also, the required reduction in brightness allows the omission of heat sinks or their dimensions to be reduced.

[0023] Display devices can be designed in a variety of ways, including LCD, LED displays, and PLED displays.

[0024] According to one embodiment, in step e), the plastic material penetrates, upon injection, into the microperforations produced in step d), such that the microperforations are partially or completely filled with the injected plastic material.

[0025] The injected plastic material may be or includes polyurethane (PUR) and / or polycarbonate (PC).

[0026] The microperforation of the decorative layer in step c), i.e. the introduction of holes in the decorative layer, can be carried out, for example, by means of a laser. This can certainly damage the substrate film. However, this does not cause damage, since it is in any case removed from the decorative part. On the other hand, if microperforations are formed in a decorative layer that has already been applied to a substrate, this can have adverse effects on the substrate, for example by clouding and / or color changes.

[0027] The substrate film provided in step a) may be a hot stamping film and / or an IMD film, i.e. a film suitable for the method called in-mold decoration (IMD for short). Step e) may constitute hot stamping, in which case the decorative layer is transferred from the substrate film to the substrate during production by heat and / or pressure.

[0028] The substrate film has, for example, a thickness of the order of magnitude of about 200 μm.

[0029] The decorative layer applied in step b) may be a lacquer coat and / or a paint coat.

[0030] The decorative layer can be applied to the base film, for example, by a printing method.

[0031] In a variant of the method, a protective layer and / or an optical layer is applied to the front side of the decorative layer, in particular after step f) or after step g), which may comprise or be formed from PUR and / or thermoplastic materials.

[0032] As intermediate steps or also after the described method steps, method steps known per se can be carried out for the final processing of the molded part, such as, for example, cutting and / or milling and / or grinding steps.

Claims

1. A method for manufacturing a decorative part for a vehicle interior, comprising the steps of: The decorative part includes a base material and a decorative layer applied to the base material, a front side of the decorative layer opposite the substrate forms a visible side of the decorative part, The method includes the steps of: a) providing a substrate film which is a hot stamping film and / or an IMD film; b) forming a composite layer by applying a decorative layer to a first surface of the substrate film; c) microperforating said decorative layer in one or more areas or over the entire surface; d) inserting or withdrawing the composite layer, consisting of the base film and the micro-perforated decorative layer, into the cavity of an injection mould such that when plastic material is injected into the cavity, the decorative layer of the composite layer is back-injected and a second side of the base film opposite to the first side is pressed against the wall of the cavity; e) closing the cavity and injecting a plastic material into the cavity to form the substrate of the decorative part, wherein during the formation of the substrate in the cavity, a back-injection is performed on the decorative layer, so that the decorative layer is applied to the surface of the substrate facing the decorative layer, thereby forming a decorative layer of the decorative part; f) opening said cavity and removing or ejecting said decorative component.

2. 2. The method according to claim 1, characterized in that after step f) the following steps are performed: g) removing the substrate film during or after the removal or ejection of the decorative part from the cavity, with the decorative layer remaining on the substrate as a decorative layer.

3. The plastic material injected in step e) is a transparent plastic material, and the formed substrate is a transparent substrate. The method according to claim 1 or claim 2.

4. The decorative part to be manufactured has a display device, The display device is attached to the back side of the substrate opposite the decorative layer and / or to a recess in the substrate; The mounting is performed such that a display area of ​​the display device faces the decorative layer, whereby a display generated by the display area is visible through the micro-perforations of the decorative layer on the visible side of the decorative part. The method according to claim 3.

5. In step e), the plastic material penetrates the microperforations created in step d) during injection, the microperforations being partially or completely filled with the injected plastic material.

5. The method according to any one of claims 1 to 4.

6. characterised in that the injected plastic material is or comprises polyurethane (PUR) and / or polycarbonate (PC), 6. The method according to any one of claims 1 to 5.

7. characterised in that the microperforation of the decorative layer in step c) is carried out using a laser; 7. The method according to any one of claims 1 to 6.

8. characterised in that the decorative layer applied in step b) is a lacquer coat and / or a paint coat.

8. The method according to any one of claims 1 to 7.

9. A protective layer and / or an optical layer is attached to the front side of the decorative layer.

9. The method according to any one of claims 1 to 8.