LAYER ARRANGEMENT WITH 3D STRUCTURE AND 2D PROJECTION OF THIS STRUCTURE AND METHOD

Description

[0001] The present invention relates to a layered arrangement comprising: a film layer provided with optical information and a three-dimensionally structured layer having a smooth side and a structured side opposite the smooth side. The structured side has at least one non-coplanar surface to the smooth side, which faces a previously defined reference location, and the structured side has at least one non-coplanar surface to the smooth side, which faces away from a previously defined reference location. The three-dimensionally structured layer is formed by a thermoplastic polymer which, at a layer thickness of 4 mm, has a visual brightness Ty (D65, 10°) according to ASTM D1003 of ≥ 10%, and the film layer provided with optical information is bonded to the structured side of the three-dimensionally structured layer.

[0002] WO 2009 / 083198 A1 describes a method for the three-dimensional reproduction of a relief and / or image original using a smooth thermoplastic film, in particular printed, as the relief base material and bearing a pictorial representation of the relief and / or image original, and a positive relief mold. During a thermoplastic forming step, the film is brought into precise alignment with the positive relief mold and thermoplastically deformed under the influence of heat. WO 2009 / 083198 A1 aims to provide a simplified method for reproducing a relief and / or image original.According to WO 2009 / 083198 A1, this is achieved by carrying out the following steps: a) presenting the thermoplastic film, b) precisely arranging a relief base material allowing a view through the film on or at a small distance above the image side of the film, with position marking indicating its relative position to each other, c) applying the relief structure to the side of the relief base material facing away from the image side of the film, corresponding to the pictorial representation, by applying a relief form material that shapes and forms the positive relief shape, d) placing the positive relief shape in a heat treatment device, e) precisely placing the side of the film facing away from the image side onto the structured upper surface of the positive relief shape, corresponding to the position marking from step b), and f) carrying out thermoplastic deformation and / or embossing of the film.

[0003] DE 10 2011 088 154 A1 describes a layered product, preferably with an optical structure such as a hologram, comprising at least one layer with highly refractive nanoparticles and / or at least one layer with low refractive nanoparticles.

[0004] DE 10 2004 044 458 A1 describes a security document with a first transparent area containing a first transparent optical element and a second area containing a second opaque optical element. The second opaque optical element exhibits a first optical effect. The first and second areas are spaced apart on a substrate of the security document such that they can be superimposed. The transparent optical element incorporates a diffraction relief structure that creates the effect of a convex lens through diffraction optics.

[0005] US 3,060,611 A describes a method for reproducing texture on a conventional printed image in simulation of an oil painting, which includes the following steps: forming a mold with brushstrokes on it that follow the printed image; then forming a transparent plastic film into which the pigments of the printed image are incorporated; then aligning the mold with the plastic film; applying heat above the film and vacuum pressure from below the mold by conventional means, thereby transferring the texture of the mold to the plastic film; removing the film from the mold; then applying a white, water-based pigment to the back of the film; and finally attaching the film to a permanent surface.

[0006] Three-dimensional relief patterns can be aesthetically pleasing decorative elements. However, a disadvantage so far is that the more material that needs to be processed, the more visual "depth" the designer wants to achieve.

[0007] The present invention aims to provide a layered arrangement which, despite a reduced overall thickness, still allows for a spatially deep impression of the three-dimensional structures contained within the layered arrangement. With such a layered arrangement, aesthetically pleasing decorative elements, for example for vehicle interiors, could be produced without requiring excessive material processing.

[0008] The problem is solved according to the invention by a layer arrangement according to claim 1. A manufacturing method is the subject of claim 14. Advantageous embodiments are specified in the dependent claims. They can be combined arbitrarily unless the context clearly indicates otherwise.

[0009] With the layer arrangements according to the invention, appealing, spatially appearing effects can be achieved with reduced construction height and thus with material savings through the optical interaction of the 3D structures and the 2D projection of these structures.

[0010] The invention is explained in more detail with reference to the following drawings, without, however, being limited to them. They show: FIG. 1 a layer arrangement and projection according to the invention FIG. 2 bis FIG. 5 further layer arrangements according to the invention

[0011] FIG. 1 Figure 1 schematically shows a layer arrangement according to the invention, comprising a film layer 100 provided with optical information and a three-dimensionally structured layer 200 with a smooth side 210 and a structured side 220 opposite the smooth side 210. "Optical information" can be represented by different printing (in which case the film 100 is a printed film), coloring, or surface roughness of selected areas of the film 100. It is also possible that the film 100 is designed as an optical waveguide and that the optical information is represented by selectively extracting light coupled laterally into the film 100.

[0012] The position of the information in or on slide 100 is not restricted. The information can be displayed on the side of slide 100 facing the structured layer 200, on the side of slide 100 facing away from the structured layer 200, or even within slide 100 itself.

[0013] The layer arrangement can be planar or non-planar (curved). Accordingly, the smooth side 210 can be planar or curved. With the exception of technically unavoidable variations, the smooth side 210 preferably has no protrusions or depressions.

[0014] The structured side 220 has at least one non-coplanar surface 230 with respect to the smooth side 210, which faces a previously defined reference point 400. Such a surface 230 is formed by elevations or peaks 240 and / or depressions or valleys 250 on the structured side 220. The reference point 400 can be a reference point. It is a conceptual position that can be understood as the eye of an observer or as a light source (to generate or simulate shadows on the structured side 220). Furthermore, the structured side 220 has at least one non-coplanar surface 235 with respect to the smooth side 210, which faces away from the previously defined reference point 400.

[0015] The three-dimensionally structured layer 200 is formed by a thermoplastic polymer which, at a layer thickness of 4 mm, exhibits a visual brightness Ty (D65 / 10°) according to ASTM D1003 of ≥ 10%. Therefore, the 3D-structured layer 200 can be considered transparent or at least partially transparent.

[0016] Examples of suitable thermoplastic polymers are the members selected from the group comprising polycarbonate, polyester carbonate, polystyrene, polyamide, styrene copolymers, aromatic polyesters, PET cyclohexanedimethanol copolymer (PETG), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), poly- or copolyacrylates and poly- or copolymethacrylate, as well as copolymers with styrene.

[0017] The term polycarbonate also includes copolycarbonates. For styrene copolymers, acrylonitrile-styrene-acrylate copolymer (ASA) is preferred; for aromatic polyesters, polyethylene terephthalate (PET) is preferred; for poly- or copolymethacrylate, poly- or copolymethylmethacrylates, in particular polymethylmethacrylate (PMMA), are preferred; and for copolymers with styrene, transparent polystyrene acrylonitrile (PSAN) is preferred.

[0018] The thermoplastic polymer may, of course, contain additives such as dyes, stabilizers, impact modifiers, and the like. Preferably, the visual brightness is ≥ 20% to ≤ 99%, and more preferably ≥ 50% to ≤ 92%.

[0019] The optically marked film layer 100 is bonded to the structured side 220 of the three-dimensionally structured layer 200. This can be done, for example, in a film injection molding process. It is preferred that the film 100 follows the contour of the structured side 220. This case is also in FIG. 1 depicted.

[0020] In the layer arrangement according to the invention, the optical information of the optically provided film layer 100 represents at least a part of a two-dimensional projection 500 of the three-dimensionally structured layer 200. Preferably, the film layer 100 is provided with the complete projection of the 3D-structured layer 200. The projection 500 is in FIG. 1 The layer arrangement is shown above for clarification. Projection 500, which represents the overall projection, contains projections 510, 520, and 530, whose boundaries are defined by the elevations 240 and depressions 250 of the structured side 220. Thus, projection 500 contains at least projections 520 and 530.

[0021] The projection 520 of at least one surface 230, which faces the reference point 400, is displayed differently on the optically information-enhanced film layer 100 than the projection 530 of at least one surface 235, which faces away from the reference point 400. By facing towards or away from the reference point 400, illumination or shadowing of the surfaces can be defined, for example. This is comparable to the representation of mountains (a three-dimensional structure) on a map (a two-dimensional structure). A reference point for a light source is chosen, and based on this, mountain slopes facing away from the light source are displayed as darker or shaded. In this way, a three-dimensional impression of the mountain is conveyed on the map.

[0022] The projection 500 can be obtained by converting a three-dimensional CAD model of the structured layer 200 into a two-dimensional image using ray tracing.

[0023] It is possible that horizontal sections of the structured page 220 are not colored in projection 500 or otherwise represented by optical information. This is also the case in FIG. 1 This is represented by projection 510. By omitting its coloring, the visual impression of the other projections 520 and 530 is enhanced.

[0024] According to one embodiment, which is also in FIG. 1 As shown, projection 500 is an orthogonal, non-shifted projection. Slide 100, including the projection, is then identical to the structured page 220.

[0025] According to another embodiment, which is also in FIG. 1 As shown, the reference point 400 faces the smooth side 210 of the three-dimensionally structured layer 200. The layer arrangement according to the invention can be used as a cover or decorative element. Preferably, the smooth side 210 is the side facing a viewer, so that the reference point 400 represents a possible position of a viewer.

[0026] According to another embodiment, which is also in FIG. 1 As shown, reference point 400 is located outside the vertical boundaries of the layer arrangement.

[0027] FIG. 2 shows the in FIG. 1 The depicted layer arrangement is shown without the projection 500 and, for clarity, without the optically provided foil layer 100, but with additional geometric descriptors h, n1, n2, and α. According to a further embodiment, in the structured side 220 of the three-dimensionally structured layer 200, the maximum vertical distance h between a peak 240 and an adjacent valley 250 is ≤ 2 mm. Preferably, the distance h is ≥ 0.1 mm to ≤ 1.5 mm, and more preferably ≥ 0.2 mm to ≤ 0.9 mm. The height h can be chosen such that the associated peak 240 projects above the horizontal plane of the structured side 220. This is exemplified in FIG. 3 depicted. In FIG. 3 For clarity, layer 100 of the foil, which contains optical information, is also not shown.

[0028] Such restricted values ​​for the distance h have the advantage that the three-dimensional structure becomes so flat that in the production of the layer arrangement the film does not need to be pre-formed, but can be inserted as a two-dimensional film into an injection molding tool (for film back injection).

[0029] Another advantage of such restricted values ​​for the distance h is that the optical quality of the smooth side 210 can be improved. The smaller the height differences on the structured side 220, i.e., the smaller h, the lower the overall variation in the mass of the thermoplastic polymer perpendicular to the smooth side 210. This results in a more uniform cooling behavior of the thermoplastic. In this way, optical defects caused by inhomogeneous cooling of the thermoplastic are avoided. The combination with the film 100 still yields an appealing three-dimensional optical effect in the layer arrangement.

[0030] According to another embodiment, which is also in FIG. 2 As shown, a surface normal n1 of a surface 230 facing the reference point 400 and a surface normal n2 of an adjacent surface 235 facing away from the reference point 400 intersect at an angle α of ≥ 5° to ≤ 175°. In this way, the inclination of surfaces 230 and 235 can be quantified. Preferably, the angle α is ≥ 20° to ≤ 70°, and more preferably ≥ 30° to ≤ 60°.

[0031] According to a further embodiment, the film layer 100 is provided with optical information by means of laser structuring, inkjet printing, laser printing, digital printing, or screen printing. A printing method such as screen printing is preferred, such that the film layer 100 is a printed film layer, the printed film layer 100 is printed with at least a part of a two-dimensional projection 500 of the three-dimensionally structured layer 200, and the projection 520 of the at least one surface 230 facing the reference point 400 is represented differently on the printed film layer 100 than the projection 530 of the at least one surface 235 facing away from the reference point 400.

[0032] According to another embodiment, wherein on FIG. 1 As reference can be made, the projection 520 of the at least one surface 230, which faces the reference point 400, on the film layer 100 provided with optical information, has a lower tonal value than the projection 530 of the at least one surface 235, which faces away from the reference point 400. The term tonal value refers to the different levels between light and dark in a color or black-and-white image, whether in a digital data set, on a transparent medium (film), or on a reflective image, photographic or printed. For an image element (dot), it describes a color or gray value within a predefined color or grayscale spectrum, specified from 0 to 100%. Here, 100% means maximum darkness or color coverage (solid tone) of the imaging medium. Correspondingly, 0% represents complete transparency of the film or blank paper in halftone printing.The tone value is determined from measurements of the optical density / reflectivity and calculated from these measurements using the Murray-Davies formula.

[0033] In the additive CMYK color model used in printing processes, the gray value can be expressed as a percentage of the K ("key," black) component. Preferably, the projection 520 of the at least one surface 230 facing the reference point 400 on the optically information-encoded film layer 100 has a lower gray value in the CMYK color model than the projection 530 of the at least one surface 235 facing away from the reference point 400. In the simplified analogy described above, "mountain slopes" facing away from the light source are represented darker than those "mountain slopes" facing the light source.

[0034] According to another embodiment, also based on FIG. 1 The tonal value of the projection 520 of at least one surface 230, which faces the reference point 400, is selected as a function of the inclination of the surface 230 relative to the horizontal. In the simplified analogy described above, "mountain slopes" facing the light source are represented differently depending on their inclination.

[0035] According to another embodiment, also based on FIG. 1 The tonal value of the projection 530 of at least one surface 235, which faces away from the reference point 400, is selected as a function of the inclination of the surface 235. In the simplified analogy described above, "mountain slopes" facing away from the light source are depicted differently, and in particular darker, depending on their inclination.

[0036] The function in the last two embodiments mentioned can, for example, be a linear function or a logarithmic function, independently of each other. A logarithmic function is advantageous in order to reflect the logarithmic progression of human sensory perceptions.

[0037] According to a further embodiment, which is described in FIG. 4 und 5As shown, on the side of the optically information-bearing film layer 100 facing away from the structured side 220 of the three-dimensionally structured layer 200, a first additional layer 300 is also present and bonded to this layer. Additionally or alternatively, on the smooth side 210 of the three-dimensionally structured layer 200, a second additional layer 310 is also present and bonded to this layer. The first additional layer 300 and the second additional layer 310 can be implemented independently of each other by a film, a lacquer, by vapor deposition, or by plasma coating. Such an additional layer 300, 310 can protect the layer arrangement from contamination or scratching.

[0038] According to another embodiment, the thermoplastic polymer from which the three-dimensionally structured layer 200 is formed is a polycarbonate. This term includes co-polycarbonates and polycarbonate blends. The polycarbonate can have a melt volume ratio (MVR) of 8 to 20 cm³ / (10 min), determined according to ISO 1133-1:2012-03 (300°C, 1.2 kg). Preferred are the homopolycarbonate based on bisphenol A, the homopolycarbonate based on 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, a copolycarbonate comprising isosorbide, 2,3-dihydro-3,3-bis(4-hydroxyphenyl)-2-methyl-1H-isoindol-1-one, 2,3-dihydro-3,3-bis(4-hydroxyphenyl)-2-phenyl-1H-isoindol-1-one, 1,3-dihydro-3,3-bis(4-hydroxyphenyl)-1-methyl-2H-indol-2-one, 1,3-dihydro-3,3-bis(4-hydroxyphenyl)-1-phenyl-2 H-indol-2-one, 1,2-dihydro-2,2-bis(4-hydroxyphenyl)-1-methyl-3H-indol-3-one and / or 1,2-dihydro-2,2-bis(4-hydroxyphenyl)-1-phenyl-3H-indol-3-one, a copolycarbonate based on the monomers bisphenol A and 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, or a mixture of at least two of the aforementioned polymers. The polycarbonate may, of course, contain additives such as colorants, stabilizers, impact modifiers, and the like.

[0039] The film layer 100 preferably contains one or more thermoplastic polymers. Examples have already been mentioned. According to a further embodiment, the optically provided film layer 100 contains a polycarbonate. This term includes co-polycarbonates and polycarbonate blends. The polycarbonate can have a melt volume ratio (MVR) of 8 to 20 cm³ / (10 min), determined according to ISO 1133-1:2012-03 (300°C, 1.2 kg). Preferred polycarbonates are the homopolycarbonate based on bisphenol A, the homopolycarbonate based on 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, a co-polycarbonate comprising isosorbide, and 2,3-dihydro-3,3-bis(4-hydroxyphenyl)-2-methyl-1. H -isoindol-1-one, 2,3-dihydro-3,3-bis(4-hydroxyphenyl)-2-phenyl-1 H -isoindol-1-one, 1,3-dihydro-3,3-bis(4-hydroxyphenyl)-1-methyl-2 H -indol-2-one, 1,3-dihydro-3,3-bis(4-hydroxyphenyl)-1-phenyl-2 H-indol-2-one, 1,2-dihydro-2,2-bis(4-hydroxyphenyl)-1-methyl-3 H -indole-3-one and / or 1,2-Dihydro-2,2-bis(4-hydroxyphenyl)-1-phenyl-3 H -indole-3-one, a copolycarbonate based on the monomers bisphenol A and 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, or a mixture of at least two of the aforementioned polymers. The polycarbonate may, of course, contain additives such as dyes, stabilizers, impact modifiers, and the like.

[0040] According to a further embodiment, the first additional layer 300 and / or the second additional layer 310 are formed by a two-component lacquer (2K lacquer), by a co-extruded film, or by a scratch-resistant coated film. Preferably, the scratch-resistant coated film is a polycarbonate film provided with a coating containing silicon oxide nanoparticles.

[0041] According to a further embodiment: the optically provided foil layer 100 has a thickness of ≥100 µm to ≤ 1000 µm (preferably ≥ 175 µm to ≤ 500 µm, more preferably ≥ 250 µm to ≤ 375 µm) and / or the three-dimensionally structured layer 200 has a maximum thickness of ≥ 1.5 mm to ≤ 6 mm (preferably ≥ 2 mm to ≤ 5 mm, more preferably ≥ 3 mm to ≤ 4 mm).

[0042] The layer arrangement according to the invention can be used as a decorative element or panel. Preferred areas of application are exterior or interior components of vehicles.

[0043] A method for producing a layer arrangement according to the invention comprises the following steps: Selecting a three-dimensional structure, wherein the structure has at least one surface 230 inclined to the horizontal, and wherein the structure has at least one surface 235 inclined to the horizontal, wherein the surface 230 and the surface 235 enclose an angle of non-180°, generating optical information which represents at least a part of a two-dimensional projection 500 of the selected three-dimensional structure on a film 100, wherein a projection 520 of the at least one surface 230 is displayed differently on the film 100 than the projection 530 of the at least one surface 235.Producing a three-dimensionally structured layer 200, according to the selected three-dimensional structure, from a thermoplastic polymer, wherein the polymer has a visual brightness Ty (D65 / 10°) according to ASTM D1003 of ≥ 10% at a layer thickness of 4 mm, such that the three-dimensionally structured layer 200 has a smooth side 210 and a structured side 220 opposite the smooth side 210; joining the film 100 to the structured side 220 of the three-dimensionally structured layer 200.

[0044] Naturally, the embodiments mentioned in connection with the subject matter of the invention can also be applied analogously to the method. For example, the optical information on the film 100 can preferably be generated by printing, and the film 100 is preferably connected to the layer 200 in such a way that the projection of the 3D structure is congruent with the structured side 220.

Claims

1. Layer arrangement, comprising: a foil layer (100) provided with optical information and a three-dimensionally structured layer (200) with a smooth side (210) and with a structured side (220) opposite to the smooth side (210), where the structured side (220) has at least one surface area (230) which is not coplanar with the smooth side (210) and where the structured side (220) has at least one surface area (235) which is not coplanar with the smooth side (210) and where the surface area (230) which is not coplanar with the smooth side (210) and the surface area (235) which is not coplanar with the smooth side (210) include an angle not equal to 180°, where the three-dimensionally structured layer (200) is formed by a thermoplastic polymer which, at a layer thickness of 4 mm, has an optical clarity Ty (D65 / 10°) of ≥ 10% in accordance with ASTM D1003 and where the foil layer (100) provided with optical information is bonded to the structured side (220) of the three-dimensionally structured layer (200), where the optical information of the foil layer (100) provided with optical information represents at least a portion of a two-dimensional projection (500) of the three-dimensionally structured layer (200), where the maximal vertical distance h between a peak (240) and an adjacent valley (250) in the structured side (220) of the three-dimensionally structured layer (200) is ≤ 2 mm, and the manner in which a projection (520) of the at least one surface area (230) is represented on the foil layer (100) provided with optical information differs from the manner in which a projection (530) of the at least one surface area (235) is represented.

2. Layer arrangement according to Claim 1, where the projection (500) is an orthogonal projection with no offset.

3. Layer arrangement according to Claim 1 or 2, where the thermoplastic polymer is selected from a member of the group comprising polycarbonate inclusive of copolycarbonate, polyester carbonate, polystyrene, polyamide, styrene copolymers, aromatic polyesters, PET-cyclohexanedimethanol copolymer (PETG), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), poly- or copolyacrylates, poly- or copolymethacrylates, copolymethyl methacrylates (PMMA), copolymers with styrene, polystyrene-acrylonitrile (PSAN) .

4. Layer arrangement according to any of Claims 1 to 3, where a straight line n1 perpendicular to the surface area (230) and a straight line n2 perpendicular to the surface area (235) intersect at an angle α of ≥ 5° to ≤ 175°.

5. Layer arrangement according to any of Claims 1 to 4, where the foil layer (100) is provided with optical information by means of laser structuring, inkjet printing, laser printing, digital printing or screen printing.

6. Layer arrangement according to any of Claims 1 to 5, where the projection (520), on the foil layer (100) provided with optical information, of the at least one surface area (230) has a lower tonal value than the projection (530) of the at least one surface area (235).

7. Layer arrangement according to Claim 6, where the tonal value of the projection (520) of the at least one surface area (230) is selected as a function of the angular deviation of the surface area (230) from horizontal.

8. Layer arrangement according to Claim 6 or 7, where the tonal value of the projection (530) of the at least one surface area (235) is selected as a function of the angular deviation of the surface area (235) from horizontal.

9. Layer arrangement according to any of Claims 1 to 8, where there is moreover, on that side of the foil layer (100) provided with optical information that faces away from the structured side (220) of the three-dimensionally structured layer (200), a first additional layer (300) present, bonded to said foil layer, and / or there is moreover, on the smooth side (210) of the three-dimensionally structured layer (200), a second additional layer (310) present, bonded to said structured layer.

10. Layer arrangement according to any of Claims 1 to 9, where the thermoplastic polymer from which the three-dimensionally structured layer (200) is formed is a polycarbonate.

11. Layer arrangement according to any of Claims 1 to 10, where the foil layer (100) provided with optical information comprises a polycarbonate.

12. Layer arrangement according to either of Claims 10 to 11, where the first additional layer (300) and / or the second additional layer (310) is / are formed by a two-component lacquer, by a coextruded foil or by a foil having a scratch-resistant coating.

13. Layer arrangement according to any of Claims 1 to 12, where: the thickness of the foil layer (100) provided with optical information is ≥ 100 µm to ≤ 1000 µm and / or the maximal thickness of the three-dimensionally structured layer (200) is ≥ 1.5 mm to ≤ 6.0 mm.

14. Process for the production of a layer arrangement according to any of Claims 1 to 13, comprising the following steps: - selection of a three-dimensional structure, where the structure has at least one surface area (230) which has angular deviation from horizontal and where the structure has at least one surface area (235) which has angular deviation from horizontal, where the surface area (230) and the surface area (235) include an angle not equal to 180°, - generation, on a foil (100), of optical information which represents at least a portion of a two-dimensional projection (500) of the selected three-dimensional structure, where the manner in which a projection (520) of the at least one surface area (230) is represented on the foil (100) differs from the manner in which the projection (530) of the at least one surface area (235) is represented, - production of a three-dimensionally structured layer (200), corresponding to the selected three-dimensional structure, from a thermoplastic polymer, where the polymer has, at a layer thickness of 4 mm, an optical clarity Ty (D65 / 10°) of ≥ 10% in accordance with ASTM D1003, in a manner such that the three-dimensionally structured layer (200) has a smooth side (210) and a structured side (220) opposite to the smooth side (210); - bonding of the foil (100) to the structured side (220) of the three-dimensionally structured layer (200).