Skin for interior trim parts of a vehicle including operating elements

Abstract

The skin (1) comprises at least one outer elastomeric layer (5) having an inner and an outer surface, and at least one operating element (8A) bonded to the inner surface of the skin layer (5). The operating element (8A) is intended to be connected to an electrical or electronic component and enable the operation of this component to be controlled. To indicate the position of the operating element (8A) within the skin (1) with minimal distortion of the skin's visual appearance, the operating surface (9) of the operating element (8A) extends within a first region (11) of the visible surface of the skin (1), which has a first surface texture that differs from the surface texture of a surrounding region (12) of the visible surface of the skin. Both textures may, in particular, produce different glosses, and the first region (11) may further comprise surface relief elements (16, 17).

Description

Technical Field

[0001] The present invention relates to a skin for vehicle interior trim parts.

Background Art

[0002] The skin includes at least an outer elastomer layer having an inner surface and an outer surface that form the visible surface of the skin, i.e., the so-called A side. The skin has an operating surface and further includes at least one operating element adhered to the inner surface of the outer layer of the skin. The operating element is intended to be connected to this component so as to be able to control the operation of an electrical or electronic component.

[0003] Automobiles such as cars or trucks are equipped with many electrical or electronic components that can be controlled by a driver or a passenger. Operating elements such as buttons, switches, and sliders used to control the operation of these components are usually mechanically attached individually or as an assembly to an opening in the trim part itself. Between the areas having the operating elements, the trim part usually includes an area formed by an elastomeric skin optionally having other functional or aesthetic parts integrated into the skin. On its outer surface, the elastomeric skin has a surface texture. This texture can be intended to mimic leather, but can also be intended to reduce the gloss of the skin material. This can be important, for example, at the top of the dashboard, to avoid overly strong light reflection.

[0004] The operating element may be adhered to the back of the elastic skin. In the method disclosed in Patent Document 1, this is done by manufacturing the skin according to a powder slush process on the mold surface and applying the operating element to the back of the powder slush skin when the skin material has not yet fully cured. In this way, the operating element adheres to the skin by the adhesive properties of the curable skin material. In a similar method disclosed in Patent Document 2, the operating element is applied to the back of the first polyurethane skin layer before the reactive material used to manufacture this skin layer is fully cured. Subsequently, a further polyurethane skin layer is sprayed onto the back of the first skin layer and the back of the operating element to embed the operating element in the elastic polyurethane skin.

[0005] In recent years, there has been an increasing interest in integrating the operating element into the skin so that it is hardly visible. For example, reference can be made to Patent Document 3 and Patent Document 4.

[0006] In Patent Document 3, the operating element is a pressure-sensitive element covered by a flexible skin material. Since it is thus invisible to the user, an assignment field is provided on the outer surface of the skin to indicate the presence of the operating element.

[0007] In Patent Document 4, a proximity sensor and a light source are arranged on the back of the skin. An icon layer between the light source and the skin can project a mark onto the skin. Thus, the switch assembly is hidden unless it is actuated to emit light by the light source. The problem with such a hidden arrangement is that in daylight, when the light source is not operating, the user cannot see the presence or position of any of the operating elements.

[0008] In Patent Document 5, this problem is solved by spraying a mark on the outer surface of the skin, or by forming the skin layer in the form of a switch or button, so that a raised portion is formed at the position of the switch or a depression around the switch or the depression. The problem with forming the skin layer in this way is that the degree of freedom in design is very limited and the position of the switch cannot be clearly shown in detail. As a result, the visual appearance of the skin may be considerably disrupted by the visual display of the position of the switch.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0010] Therefore, an object of the present invention is to provide a new skin having an operating element, more specifically an operating element capable of indicating the position of its operating surface, with minimal distortion of the visual appearance of the skin.

Means for Solving the Problems

[0011] For this purpose, the skin according to the invention is characterized in that the operating surface of the operating element extends into a first region of the visible surface of the skin, which is at least partially surrounded by a second region of the visible surface of the skin, the outer surface of the outer layer having a first surface texture on at least a part of the first region and a second surface texture different from the first surface texture on the second region. The operating element is configured to be connected to an electrical or electronic component, in particular in order to enable a user to control the operation of this electrical or electronic component.

[0012] The texture of the surface of the skin is the visual or tactile surface characteristics of this surface and its appearance. The surface of the skin may be quite rough or completely smooth. Even if the surface is completely smooth or flat, this is considered to be a textured surface, that is, the absence of texture is also considered to be a texture.

[0013] The texture is formed by the surface of the outer elastomer layer, but not by the shape of the outer elastomer layer itself. When molding the elastomer layer, the shape of the outer surface of the elastomer layer is generally the shape of the negative inner surface. On the contrary, the texture of the outer surface is independent of the texture of the inner surface of the elastomer layer. In practice, the inner surface of the elastomer layer may be a smooth surface, while the outer surface may exhibit a rougher surface texture.

[0014] More specifically, the texture includes, in particular, the surface characteristics that affect the gloss of the surface. Since the surface texture is defined by the outer surface of the outer elastomer layer itself, the shape or form of the outer elastomer layer does not need to be modified to indicate the presence of the operating surface of the operating element. This means that there is no need to distort the shape or form of the visible surface of the skin in order to provide an indication of the position of the operating surface of the operating element. Instead, only the surface texture of the outer surface of the outer layer needs to be modified. In other words, the overall contour and visual appearance of the visible surface of the skin can be maintained.

[0015] The surface texture of the outer surface of the outer elastomer layer is preferably a molded surface texture, i.e., a surface texture obtained by molding the outer elastomer layer against a textured mold surface. The outer elastomer layer may be made of a thermoplastic material that is molded in a molten state against the mold surface in a slush molding process or the like. Alternatively, a layer (foil) of such a thermoplastic material may be molded against the mold surface in a solid state. The solid layer of the thermoplastic material is molded by urging or sucking it against the textured mold surface with sufficient pressure so that the negative texture of the mold surface is transferred to the skin layer. The skin layer and / or the mold surface are preferably heated to assist the molding process. The elastomer layer may also be manufactured from a reactive mixture, such as a polyurethane reactive mixture, which can be applied in a liquid state against the textured mold surface and cured against this mold surface.

[0016] Preferably, the second surface texture is visually different from the first surface texture. This can be achieved in various ways. One of the textures can be, for example, a rough texture, and the other texture can be a finer texture. Both textures can be rough, but may also include other texture elements having different shapes. Alternatively or additionally, both textures may have different light reflection characteristics such that different texture regions have different glosses. One region may be, for example, matte, and the other region may be glossier.

[0017] An important advantage of distinguishing the first and second regions of the visible surface of the skin by different surface textures is that such different surface textures can be easily obtained without additional process steps by molding the outer elastomer layer against a mold surface provided with negative first and second surface textures.

[0018] In one embodiment of the skin according to the present invention, a part of the first region forms a visible display indicating the presence of the operating surface of the operating element.

[0019] The visible display may be a symbol or an icon. It may also be letters or numbers, having several letters or numbers formed by different parts of the first region, preferably forming even a word or text or numbers.

[0020] In one embodiment of the skin according to the present invention, the outer surface of the outer elastomer layer has at least one surface relief element in the first region that forms a visible display indicating the presence of the operating surface of the operating element, and this surface relief element includes at least one depression on the outer surface, the thickness of the outer elastomer layer is thin, and / or includes at least one raised portion on the outer surface, and the thickness of the outer elastomer layer is thick.

[0021] The visible display formed by the surface relief element may be a symbol or an icon. It may also be letters or numbers, having several letters or numbers formed by different parts of the first region, preferably forming even a word or text or numbers.

[0022] Similar to the first and second surface textures, the surface relief element is not formed by the shape or form of the outer elastomer layer itself, but is formed as a raised portion or a depression on the outer surface of the outer elastomer layer. Therefore, the surface relief element is generally only visible on one side of the outer layer, that is, its outer (visible) surface. One or more surface relief elements can be distinguished individually (visually, preferably also tactilely), and thus appear as individual elements on the outer surface of the outer elastomer layer.

[0023] Thus, in one embodiment of the skin according to the invention having at least one surface relief element in the first region, one or more surface relief elements cover preferably less than 50%, more preferably less than 40%, and more specifically less than 30% of the surface of the first region. In this way, they are at a substantial distance from each other.

[0024] Preferably, the depression and / or the elevation create a height difference of at least 0.10 mm, preferably at least 0.15 mm on the outer surface. The height difference can be even larger and can be greater than 0.20 mm, greater than 0.25 mm, or greater than 0.30 mm.

[0025] Such a height difference makes the surface relief elements better distinguishable individually. The height difference is determined as the maximum vertical height difference between the surface relief element and the surface area immediately adjacent to the surface relief element. When the surface relief element is a protrusion located immediately adjacent to a surface relief element formed by a depression, the height difference caused by the protrusion or the height difference caused by the depression is the height difference between the top of the protrusion and the bottom of the depression measured on a profile in a plane perpendicular to the outer surface of the outer layer.

[0026] Preferably, the surface relief element has a projected surface area on a flat plane in contact with the outer surface of the outer elastomeric layer of at least 1 mm 2 and preferably at least 2 mm 2 . This also helps to distinguish the surface elements individually.

[0027] In one embodiment of the skin according to the invention having at least one surface relief element in the first region, at least a part of the surface of the surface relief element has a first surface texture.

[0028] Due to the difference in texture between the surface of the surface relief element and the surface of the second region of the visible surface of the skin, the surface relief element becomes more distinguishable from the second region of the visible surface. Therefore, this feature helps to more clearly indicate the position of the operating surface of the operating element.

[0029] In one embodiment of the skin according to the invention having at least one surface relief element in the first region, the outer surface of the outer layer has a first surface texture on at least a part of the first region adjacent to the surface relief element.

[0030] Due to the difference in texture between the surface of the first region adjacent to the surface relief element, or, if there are several surface relief elements in the first region, the surface between the surface relief elements, and the surface of the second region of the visible surface of the skin, the first region can be more easily distinguished from the second region. In other words, the position of the surface relief element is more clearly indicated on the visible surface of the skin.

[0031] In another embodiment of the skin according to the invention having at least one surface relief element within the first region, at least a part of the surface of the surface relief element and at least a part of the first region adjacent to the surface relief element have a first surface texture. In this way, most of the first region, or preferably substantially the entire first region, has a first surface texture and can thus be more easily distinguished from the second region of the visible skin surface as a whole, clearly indicating the position of the operating surface of the operating element.

[0032] In one embodiment of the skin according to the invention, the second surface texture is different from the first surface texture in order to generate a difference in gloss value between the part of the first region having the first texture and the second region having the second surface texture. The second surface texture has, in particular, a profile (outer surface, contour) with a different roughness and / or a different root mean square gradient value from the first surface texture.

[0033] The difference in gloss serves to distinguish a first region and a second region of the visible surface of the skin. Since the difference in gloss is generated by the surface texture, no additional post - treatment steps such as post - painting or other post - surface treatment of the generated skin are required to obtain this difference. The advantage of the difference in gloss is that it clearly visually shows the difference in surface texture. A further advantage is that it is associated with a different tactile sensation. Thus, the driver can feel the difference in texture so that they do not need to look at the skin to see the exact position of the operating surface of the operating element.

[0034] The gloss values of the first and second regions s can be measured in accordance with ASTM D523 - 14(2018). The roughness of the surface texture, in particular the roughness Ra, can be measured as defined in DIN EN ISO4287:1998, and the root - mean - square gradient value, in particular the delta q value Rdq, can be determined in accordance with DIN EN ISO4287:1998. The greater the surface roughness Ra, i.e., the higher the peaks and the deeper the valleys, and / or the greater the delta q value, i.e., the steeper the gradient, the smaller the specular reflection of light, in other words, the less light is reflected into the eye, and thus the lower the gloss of the skin surface.

[0035] In one embodiment of the skin according to the invention, the first surface texture is smoother than the second surface texture to provide a higher gloss by a part of the first region having the first surface texture, and the second region of the skin has a gloss value, in particular, measured in accordance with ASTM D523 - 14(2018) at an angle of less than 2.0, more particularly less than 1.5, at 60°.

[0036] The more shiny area enables it to be clearly distinguished from the surrounding area, especially when the surrounding area is a matte area. In particular, in a matte area where the gloss value is less than 2.0, or even less than 1.5 gloss units (100 gloss units corresponding to the gloss value of the black glass standard), a difference of several gloss units, especially a difference of 2.0 gloss units, can be easily recognized by the human eye. In particular, when forming an elastomer layer on a smooth mold surface such that the outer surface has a roughness Ra defined by DIN EN ISO4287:1998 (in combination with ISO11562:1996 which specifies a Gaussian phase correction filter for removing fine roughness profiles) of less than 10 μm, the gloss value of the outer surface is at least 2 - 3 gloss units higher than that of a more coarsely textured outer surface and can include, for example, 4 gloss units for an elastomer mold polyurethane layer.

[0037] In one embodiment of the skin according to the invention, the skin comprises an inner layer adhered to the inner surface of the outer layer, and the operating element preferably comprises a sensor element and a light source and is embedded between the outer layer and the inner layer.

[0038] The advantage of this embodiment is that the operating element is completely shielded from dust or moisture. Furthermore, the operating element can be easily and completely integrated when forming the two skin layers against the mold surface. Thus, the operating element is protected from damage when transferring the skin to the next mold, especially a backform mold, and the substrate is adhered to the back of the skin via a foam layer.

[0039] The operating element may comprise a mechanical switch element having two stable positions. In one embodiment of the skin according to the invention, the operating element includes a sensor element. Such a sensor element can be more reliable and compact than a bistable mechanical on / off switch. The sensor element may be a contact sensor, such as a resistance sensor or a pressure sensor, or may be a remote sensor, such as a capacitance sensor, an infrared sensor or an electromagnetic sensor, which enables reading RFID data, for example.

[0040] Preferably, the operating element further comprises a light source. This light source is preferably activated when the operating element is operated.

[0041] In one embodiment of the skin according to the invention, the visible surfaces of the skin in the first region and the second region are formed of exactly the same material.

[0042] The elastomer layer may be manufactured from one material or may further comprise a coating layer applied by an in-mold coating process, thus forming the outer surface of the (composite) outer elastomer layer. Thus, the visible surface is formed by a single material of the outer layer or a coating layer in both the first region and the second region. Thus, there is no need to apply the coating layer separately to the first region or the second region to indicate the position of the first region within the second region, or to remove a part of the coating layer, for example by laser. Thus, the visible outer surface of the skin is preferably formed in one step against the mold surface when the skin is molded.

[0043] The invention also relates to a vehicle trim part comprising a skin according to the invention adhesively bonded to a substrate layer, in particular via an intermediate foam layer.

[0044] Finally, the invention also relates to a method for manufacturing a skin according to the invention, a step of applying the outer surface of the outer elastomer layer against a mold surface to mold the outer elastomer layer, wherein the mold surface is provided with a negative first surface texture for generating a first surface texture on the outer surface of the outer elastomer layer and a negative second surface texture for generating a second surface texture on the outer surface of the outer elastomer layer, and a step of bonding an operating element to the inner surface of the outer layer.

[0045] The advantage of this method is that one or more relief elements, which further indicate different textures of the visible surface of the skin and optionally the position of the operating elements, are obtained immediately in one step during the shaping process.

[0046] In a preferred embodiment of the method according to the invention, it comprises a further step of embedding the operating element between an outer layer and an inner layer, the inner layer being adhered to the inner surface of the outer layer after the operating element has been placed against the inner surface of the outer layer, the operating element preferably comprising a sensor element and a light source.

[0047] Manufacturing the skin in two layers is actually already being done. For example, reference can be made to European Patent No. 2024413, in which the outer layer is made of a light-stable aliphatic polyurethane material and the inner layer is made of a more flexible aromatic polyurethane material. The operating element can be easily embedded in the correct position between the two layers by placing it on the back side of the first layer before spraying the second layer.

[0048] Other advantages and particularities of the present invention will become apparent from the following description of some specific embodiments of the skin according to the present invention and the method of manufacturing the skin. This description is given by way of example only and is not intended to limit the scope of the present invention. The reference numbers used in this specification relate to the accompanying drawings.

Brief Description of the Drawings

[0049]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

DETAILED DESCRIPTION OF THE INVENTION

[0050] The present invention generally relates to a skin 1 for vehicle interior trim parts 2 such as dashboards, door panels, consoles, glove compartment lids, etc. As shown in FIG. 3, the trim part comprises a skin 1 adhered to a rigid base material layer 3. The skin 1 can be adhered directly to the base material layer 3 by an adhesive or by an overmolding process in which the skin 1 is molded onto the base material layer 3. Preferably, the skin 1 is adhered to the base material layer 3 via a foam layer 4. This foam layer 4 can be produced by a molding process between the skin 1 and the base material layer 3.

[0051] The skin 1 according to the present invention includes at least a flexible outer elastomer layer 5, and the inner surface 6 and the outer surface 7 form the visible surface of the skin 1, i.e., the A surface. The outer elastomer layer 5 may be a thermoplastic layer or foil, particularly a TPE (thermoplastic elastomer) layer such as a TPO or PVC skin. Such a thermoplastic skin layer can be molded by a thermoforming process or, for example, by a slush molding process. The elastomeric outer skin layer 5 can also be produced starting from a curable composition, particularly a curable polyurethane composition. This curable composition is a fluid material that is applied onto a mold surface and cured on that mold surface to produce the outer elastomeric skin layer 5.

[0052] The curable composition can be applied to the surface of an open mold by a spraying process or can be applied to a closed mold, more specifically poured, but preferably injected according to a reaction injection moulding (RIM) process. A light-stable colored PU reaction mixture can be used. Reference can be made to European Patent No. 0303305, European Patent No. 0379246, International Publication No. 98 / 14492 pamphlet, European Patent No. 0929586 and International Publication No. 04 / 000905 pamphlet, which are hereby incorporated by reference into this specification.

[0053] In a variant embodiment, a finishing layer, in particular a light-stable paint or a so-called in-mold coating (either water- or solvent-based), can be applied to the mold surface as a first coating layer. This paint is subsequently composed with the elastomeric layer to be applied and the outer elastomeric skin layer 5.

[0054] The skin layer 5 is elastomeric, which generally means having an elongation of at least 30%, preferably at least 50%, as measured according to DIN / EN / ISO527-3. Its flexural modulus measured according to ASTM D790-03 is preferably less than 100 MPa, more preferably less than 75 MPa, most preferably less than 55 MPa, or even less than 40 MPa. Generally, its overall density is greater than 300 kg / m 3 greater, preferably greater than 500 kg / m 3 greater, more preferably greater than 600 kg / m 3 greater.

[0055] In contrast to the outer layer 5, the base layer 3 is relatively rigid and has a flexural modulus of more than 500 MPa, preferably more than 700 MPa, as measured in accordance with ASTM D790. The base layer can be made of a thermosetting material, but the base is preferably made of a thermoplastic material. This thermoplastic material is preferably selected from the group consisting of PC (polycarbonate), ABS (acrylonitrile butadiene styrene) and ABS blends, especially PC / ABS, SMA (styrene maleic anhydride), PPO (polyphenylene oxide), TPO (thermoplastic olefin), especially PP (polypropylene), polyacetal, especially POM (polyoxymethylenes), nylon, polyester, acrylic and polysulfone.

[0056] The outer elastomeric skin layer 5 may also be manufactured from two or more layers, each manufactured from a curable composition, as described in WO 2007 / 137623.

[0057] The skin 1 according to the invention has an operating surface 9 and further comprises at least one operating element 8 adhered to the inner surface 6 of the outer elastomeric layer 5. In the present specification and claims, the term operating element refers to an element configured to be connected to an electrical or electronic component to enable a user to control the operation of this component.

[0058] To adhere the operating element 8 to the outer layer 5, the operating element 8 can be adhered by an adhesive, or when the material of the outer layer 5 has not yet fully cured, the operating element 8 can be applied to the operating element 8 during the manufacture of the outer layer. It is also possible to apply the operating element 8 onto the base layer 3 and overmold the operating element 8 together with the base layer 3 with the liquid material used to manufacture the outer layer 5.

[0059] In the embodiment shown in FIG. 3, the operating element 8 is adhered to the outer elastomer layer 5 by an inner elastomer layer 10 formed on the inner surface of the outer elastomer layer 5. The inner elastomer layer 5 may have the same composition and may be manufactured in the same manner as described above for the outer elastomer layer 5. In particular, both layers 5 and 10 can be manufactured as disclosed in WO 2007 / 137623. The outer elastomer layer 5 is preferably manufactured by applying a first curable polyurethane composition to the mold surface and the inner elastomer layer 10, by applying a second curable polyurethane composition to the back surface of the outer elastomer layer 5. The first curable polyurethane composition is preferably an aliphatic polyurethane composition, and the second curable polyurethane composition is preferably an aromatic polyurethane composition.

[0060] The trim part 2 shown in FIG. 1 is a dashboard. The dashboard 2 includes an elastomer skin 1 having an opening for integrating functional elements such as an instrument panel into the skin 1. The skin 1 also includes an area integrated on the back side of the skin so that the operating element 8 is hidden from view. These operating elements 8 may be provided on an electronic printed foil 15 having a tail protruding from the trim part 2 so that the operating element 8 can be connected to a controller.

[0061] To avoid deformation of the integrated area when the product is exposed to different ambient temperatures, the integrated printed foil preferably has a shrinkage rate similar to that of the elastomer skin and / or the E modulus (Young's modulus) must be the same as or less than the E modulus of the elastomer layer. Printed foils of TPU material are very suitable for use in combination with elastomer materials.

[0062] The electronic printed foil can already be foreseen with electronic surface mount devices such as LEDs, tactile actuators, electric coils for non-contact charging, RFID readers, antennas, etc. The printed foil may be an OLED display.

[0063] The first operating element 8A may be intended to turn on the illumination behind other hidden operating elements so that the other hidden operating elements can be seen. This comprises an on / off switch formed by a pressure sensor 13 having an operating surface 9. The first operating element 8A also comprises a light source 14 having two opposing LEDs 14A and 14B. The space between the LEDs is filled with a light guiding material that diffuses the light of the LEDs in different directions to create a uniform illumination of the first region 11. Furthermore, the light source 14 can be completely or partially covered by an optical filter that filters a specific wavelength, for example to show a colored image. Such an optical filter also forms part of the light source 14 since it determines the wavelength of the light supplied to the inner surface 6 of the outer elastomer layer 5 by the light source 14. The LEDs 14A and 14B are biased during the initial actuation of the pressure sensor 13 and have a visual indication of the actuation of the operating element 8A, making it possible to see the position of the first operating element 8A more clearly. Also, the light sources of the other hidden operating elements 8 may be biased during the actuation of the first operating element 8A so that they become visible to the user.

[0064] To indicate the position of the first operating element 8A when its light source 14 is not energized, the operating surface 9 of the first operating element 8A is located within the first region 11 of the visible surface of the skin 1 surrounded by the second region 12 of this visible surface. At least a part of the first region 11 has a first surface texture that is different from the surface texture of the second region 12, i.e. different from the second surface texture.

[0065] Typically, the second surface texture is present over a major portion of the surface of the skin. This second surface texture may be, for example, a leather texture or any other texture used for trim parts. Such a leather texture is shown at a larger microscopic scale in FIG. 4. It has very deep valleys and very high mountains, and the surface forming the mountains and valleys is also very rough. The Ra value (roughness value) measured as defined in DIN EN ISO 4287:1998 (arithmetic mean deviation of the evaluated texture profile) includes, for example, the illustrated texture profile of 54 μm, but the Pt value, i.e., the total height of the profile measured as defined in DIN EN ISO 4287:1998 (sum of the height of the maximum profile peak and the maximum profile valley depth within the evaluation length) includes, for example, about 220 μm. The root mean square gradient value, in particular the delta q value Rdq determined in accordance with DIN EN ISO 4287:1998, is equal to, for example, about 1.27. The larger the delta q value, the steeper the gradient of the profile and the greater the diffuse reflection of light and thus of the surface of the substance. Higher roughness also causes the surface of the substance. These parameter values of the second surface texture and the reflection coefficient of the polyurethane material from which the skin is made (by the spray process against the textured mold surface) cause the gloss value of the skin 1 shown above and in FIG. 4 to include about 0.2 gloss units in its second region 12.

[0066] As shown in FIG. 4, the first surface texture is preferably smoother than the second surface texture. In this way, the surface of the first skin region 11 has a higher gloss than the surface of the second skin region 12. This means that the first skin region 11 has a higher specular reflection of light and a lower diffuse reflection than the second skin region 12. This helps the first skin region 11 to appear within or adjacent to the second skin region 12. The gloss difference between the first skin region and the second skin region can be measured in accordance with ASTM D523-14 (2018). Usually, this is done at an angle of 60°, but for low gloss values, measuring at an angle of 85° can more clearly determine different gloss values (resulting in higher gloss values).

[0067] The first surface texture can be generated with respect to a perfectly smooth mold surface, i.e., a non-textured mold surface that can even be polished. Depending on the skin material, the surface of the skin becomes smoother or less smooth. When the skin material is applied to the mold surface in liquid form, its viscosity can affect, for example, the smoothness of the resulting skin surface. The gloss of the resulting skin surface also depends on the composition of the skin material. In the case of a polyurethane skin produced by spraying a curable polyurethane material onto the mold surface, the gloss value can be composed of, for example, 3 to 6 gloss units. If a higher gloss is desired, a mold coating, such as a lacquer, can be first applied to the mold surface.

[0068] To more clearly indicate the position of the first operating element without lighting, surface relief elements are provided in the first surface area, i.e., the position of the first operating element 8A. These surface relief elements include a central icon 16 indicating an on / off switching function, surrounded by a circle of dots 17 that form not only a clear visual display but also a clear tactile display of the position of the first operating element 8A. The dots 17 actually resemble raised Braille dots but are made larger so that they can be easily felt by even inexperienced users. Inside the circular icon 16, since the surface of the skin is completely smooth, the concave area within the circular icon 16 can be felt to clearly indicate to the user the location where the user has to press to activate the first operating element 8A.

[0069] In the cross-section shown in FIGS. 3 and 4, it can be seen that the icon 16 and the dots 17 have a height h, or in other words, are of a size similar to the total profile height Pt of the second surface texture, and in particular provide a height difference h included between 0.15 mm and 0.2 mm. This height difference corresponds to an increase in the thickness of the outer elastomer layer 5 at the position of the icon 16 or the dots 17.

[0070] In an alternative embodiment, the icon 16 and / or the dot 17 can be formed by corresponding depressions on the outer surface 7 of the outer skin layer 5 instead of being raised.

[0071] In the embodiments shown in FIGS. 2 to 4, not only the epidermal surface adjacent to the dot 17 and adjacent to the icon 16, but also the surfaces of the dot 17 and the icon 16 themselves are completely smooth, so the gloss difference between the first surface region 11 and the second surface region 12 is maximized. In an alternative embodiment, the surfaces of the dot 17 and the icon 16 can be made rougher so that the dot 17 and the icon 16 are prominent and more perceptible. Due to the bevel edges of the dot 17 and the icon 16, when they have a smooth surface, they reflect light in different directions to assist their visibility.

[0072] FIG. 5 shows the surface of the epidermis 1 at the position of the second operating element 8B. This element 8B comprises an elongated sensor element that enables detection of the position of the user's finger and any sliding movement thereof. Thus, such a slider enables control of, for example, the volume of a radio, temperature, fan speed, opening and closing of a window, etc. The first surface region also has a smooth surface texture and comprises dots 18 having the same shape as the dots shown in FIG. 4. More specifically, they have a rounded dome shape so that the user can easily slide their finger over the first region 11. The dots 18 also have a smooth surface, and even between the dots 18, the first surface region 11 is smooth. The first surface area 11, which has a narrow and elongated shape, thus forms an indication that when the user slides their finger to the narrow side, the value of the parameter controlled by the second operating element 8B decreases, while when the user slides their finger to the wide side, the value of the parameter controlled by the second operating element 8B increases.

Claims

1. At least one outer elastomer layer (5) having an inner surface (6) and an outer surface (7), and at least one operating element (8) adhered to the inner surface (6) of the outer layer (5) and having an operating surface (9), wherein the outer surface (7) of the outer elastomer layer (5) forms a visible surface of the skin, and the skin (1) for a vehicle interior trim part (2), the operating surface (9) of the operating element (8) extends into a first region (11) of the visible surface of the skin (1) at least partially surrounded by a second region (12) of the visible surface of the skin (1), the outer surface (7) of the outer layer (5) has a first surface texture on at least a part of the first region (11), the second region (12) has a second surface texture different from the first surface texture, and the operating element (8) is configured to be connected to an electrical or electronic component to enable control of the operation of the electrical or electronic component, characterized in that the skin (1).

2. The outer surface (7) of the outer elastomer layer (5) has at least one surface relief element (16, 17, 18) that forms a visible indication of the presence of the operating surface (9) of the operating element (8) in the first region (11), the surface relief element (16, 17, 18) includes at least one depression in the outer surface (7) and the thickness of the outer elastomer layer (5) is reduced, and / or includes at least one protrusion in the outer surface (7) and the thickness of the outer elastomer layer (5) is increased, the skin according to claim 1.

3. The skin according to claim 2, characterized in that the depression and / or the protrusion generates a height difference (h) of at least 0.10 mm on the outer surface (7).

4. The skin according to claim 2 or 3, characterized in that at least a part of the surface of the surface relief element (16, 17, 18) has the first surface texture.

5. The skin according to any one of claims 2 to 4, characterized in that the outer surface of the outer layer has the first surface texture on at least a part of the first region (11) adjacent to the surface relief element (16, 17, 18).

6. The surface relief elements (16, 17, 18) have a projected surface area of at least 1 mm on a flat plane in contact with the outer surface (7) of the outer elastomer layer (5). ２ The skin according to any one of claims 2 to 5, characterized in that it has a projected surface area of at least 1 mm on a flat plane in contact with the outer surface (7) of the outer elastomer layer (5).

7. The skin according to claim 1, wherein a part of the first region (11) forms a visible display indicating the presence of the operation surface (9) of the operation element (8).

8. The skin according to any one of claims 1 to 7, wherein the second surface texture is visually different from the first surface texture.

9. The skin according to any one of claims 1 to 8, wherein the second surface texture is different from the first surface texture in order to generate a difference in gloss value between a part of the first region (11) having the first texture and the second region (12) having the second surface texture.

10. The skin according to claim 9, wherein the second surface texture has a profile having a roughness different from that of the first surface texture.

11. The skin according to claim 9 or 10, wherein the second surface texture has a profile having different root mean square gradient values.

12. The part of the first region (11) of the skin (1) has a higher gloss value measured according to ASTM D523-14 (2018) at an angle of 60° than the second region (12) of the skin (1), and the second region (12) of the skin (1) has a gloss value measured according to ASTM D523-14 (2018) at an angle of less than 2.0 at 60°. The skin according to any one of claims 1 to 11, characterized in that it has a value.

13. The skin according to any one of claims 1 to 12, wherein the skin (1) includes an inner elastomer layer (10) adhered to the inner surface (6) of the outer layer (5), and the operation element (8) is embedded between the outer layer (5) and the inner layer (10).

14. The skin according to any one of claims 1 to 13, wherein the operation element (8) comprises a sensor element (13).

15. The skin according to any one of claims 1 to 14, wherein the operation element (8) comprises a light source (14).

16. The skin according to any one of claims 1 to 15, wherein the visible surfaces of the skin (1) in the first region (11) and the second region (12) are formed of exactly the same material.

17. A vehicle interior trim part having the skin according to any one of claims 1 to 16, wherein the skin (1) is adhered to a base material layer (3).

18. The vehicle interior trim part according to claim 17, characterized in that the operating element (8) is connected to an electrical or electronic component.

19. A method for manufacturing the skin according to any one of claims 1 to 16, A step of forming the outer elastomer layer (5) by bringing the outer surface (7) of the outer elastomer layer (5) into contact with a mold surface, wherein the mold surface is provided with the negative first surface texture for generating the first surface texture on the outer surface (7) of the outer elastomer layer (5), and the negative second surface texture for generating the second surface texture on the outer surface (7) of the outer elastomer layer (5); A step of adhering the operating element (8) to the inner surface (6) of the outer layer (5). A manufacturing method comprising the steps of:

20. The method according to claim 19, characterized in that the operating element (8) is adhered to the inner surface (6) of the outer layer (5) before the outer layer (5) is removed from the mold surface.

21. The method according to claim 19 or 20, further comprising a step of embedding the operating element (8) between the outer layer (5) and the inner layer (10), wherein the inner layer (10) is adhered to the inner surface (6) of the outer layer (5) after disposing the operating element (8) with respect to the inner surface (6) of the outer layer (5).

Images