Patent Application
20220152971
The present invention relates to a layer arrangement, comprising: a foil layer provided with optical information and a three-dimensionally structured layer with a smooth side and with a structured side opposite to the smooth side. The structured side has at least one surface area which is not coplanar with the smooth side and which faces toward a predefined reference location, and the structured side has at least one surface area which is not coplanar with the smooth side and which faces away from a predefined reference location. The three-dimensionally structured layer 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 the foil layer provided with optical information is bonded to the structured side of the three-dimensionally structured layer.
WO 2009/083198 A1 describes a process for the three-dimensional reproduction of a relief original and/or image original with use, as relief base material, of a smooth thermoplastic foil which is provided with a graphical depiction of the relief original and/or image original, and in particular is printed, and of a positive relief mold where, during a thermoplastic deformation step, said foil is brought into precisely fitting mutual superposition with the positive relief mold and is thermoplastically deformed with exposure to heat. The intention in WO 2009/083198 A1 is to devise a solution that provides a simplified process for the reproduction of a relief and/or image original. According to WO 2009/083198 A1, this is achieved by carrying out the following steps: a) provision of the thermoplastic foil, b) with position-marking of their position relative to one another, precisely fitting arrangement, on or at a small distance above the image side of the foil, of a relief mold base material through which the foil can be seen, c) by application of a relief mold material that shapes and forms the positive relief mold, application, in correspondence with the graphical depiction, of the relief structure to that side of the relief mold base material that faces away from the image side of the foil, d) introduction of the positive relief mold into a heat-treatment device, e) in correspondence with the position-marking from the step b), precisely fitting placement, onto the structured upper side of the positive relief mold, of that side of the foil that faces away from the image, and f) thermoplastic deformation of, and/or embossing of, the foil.
Three-dimensional relief patterns can represent aesthetically pleasing decorative elements. However a disadvantage hitherto is that when the designer wishes to achieve more optical “depth” this always requires processing of a greater quantity of material.
The present invention has addressed the object of providing a layer arrangement which has reduced total thickness but where the three-dimensional structures present in the layer arrangement can nevertheless provide an impression of three-dimensional depth. With this type of layer arrangement it is possible to produce aesthetically pleasing decorative elements, for example for the interior of vehicles, without any need to process an excessive quantity of material.
The object is achieved according to the invention by a layer arrangement as claimed in claim 1. Claim 15 provides a production process. Advantageous further developments are stated in the dependent claims. They can be combined in any desired manner, unless the context clearly indicates the opposite.
With the layer arrangements according to the invention it is possible, through the optical interaction between the 3D structures and the 2D projection of said structures, to achieve pleasing effects with attractive three-dimensional qualities, with reduced structural thickness and therefore with saving of material.
The invention is explained in more detail with reference to the following drawings, but without any restrictions thereto.
There is no restriction on the position of the information in or on the foil 100. The information can thus be represented on that side of the foil 100 that faces toward the structured layer 200, or can be present on that side of the foil 100 that faces away from the structured layer 200, or else within the foil 100.
The layer arrangement can be designed to be planar or else nonplanar (curved). Correspondingly, the smooth side 210 can be planar or curved. It is preferable that the smooth side 210 has no elevations or depressions other than technically unavoidable fluctuations.
The structured side 220 has at least one surface area 230 which is not coplanar with the smooth side 210 and which faces toward a predefined reference location 400. This type of surface 230 is formed by elevations or peaks 240 and/or depressions or valleys 250 on the structured side 220. The reference location 400 can be a reference point. It is an imaginary position which can be interpreted as the eye of an observer or as light source (for creating or simulating shadows projected onto the structured side 220). The structured side 220 moreover has at least one surface area 235 which is not coplanar with the smooth side 210 and which faces away from the predefined reference location 400.
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. The 3D-structured layer 200 can therefore be regarded as transparent or at least to some extent transparent.
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 and also copolymers with styrene.
The term polycarbonate here also comprises copolycarbonates. In the case of styrene copolymers, preference is given to acrylonitrile-styrene-acrylate copolymer (ASA), and in the case of aromatic polyesters preference is given to polyethylene terephthalate (PET), and in the case of poly- or copolymethacrylate preference is given to poly- or copolymethyl methacrylates, in particular polymethyl methacrylate (PMMA), and in the case of copolymers with styrene preference is given to transparent polystyrene-acrylonitrile (PSAN).
It is self-evident that the thermoplastic polymer can comprise additives such as colorants, stabilizers, impact modifiers and the like. The optical clarity Ty is preferably ≥20% to ≤99%, and more preferably ≥50% to ≤92%.
The foil layer 100 provided with optical information is bonded to the structured side 220 of the three-dimensionally structured layer 200. Said bonding can by way of example be achieved in in-mold foil coating. It is preferable that the foil 100 conforms to the profile of the structured side 220. This is also the situation depicted in
A feature of the layer arrangement according to the invention is that 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. It is preferable that the foil layer 100 is provided with the complete projection of the 3D-structured layer 200. For clarification the projection 500 is depicted in
The manner in which the projection 520 of the at least one surface area 230 facing toward the reference location 400 is represented on the foil layer 100 provided with optical information differs from the manner in which the projection 530 of the at least one surface area 235 facing away from the reference location 400 is represented. The direction of facing, toward or away from, the reference location 400 can by way of example define illumination effects or shadow effects on the surface areas. This is comparable with the representation of mountains (a three-dimensional structure) in a map (a two-dimensional structure). A reference location for a light source is selected, and on the basis of this hillsides facing away from the light source are represented in darker color or with shadowing. A three-dimensional impression of the mountain is thus provided on the map.
The projection 500 can be obtained by using a ray-tracing method to convert a three-dimensional CAD model of the structured layer 200 to a two-dimensional image.
It is possible that, in the projection 500, horizontal sections of the structured side 220 are not colored or represented in any other manner by optical information. This is also depicted in
In one embodiment, which is likewise shown in
In another embodiment, which is likewise shown in
In another embodiment, which is likewise shown in
These restricted values for the distance h have the advantage that the three-dimensional structure is sufficiently flat to remove any need for preforming of the foil during the production of the layer arrangement; said foil can instead be inserted in the form of two-dimensional foil into an injection mold (for in-mold foil coating).
Another advantage of such restricted values for the distance h is that the optical quality of the smooth side 210 can be improved. The overall effect of smaller height differences in the structured side 220, i.e. of smaller h, is that the fluctuation in the mass of the thermoplastic polymer, perpendicular to the smooth side 210, is also smaller. This then results in greater uniformity of cooling behavior of the thermoplastic. Optical defects due to inhomogeneous cooling of the thermoplastic are thus avoided. The layer arrangement nevertheless gives a pleasing three-dimensional optical impression as a result of combination with the foil 100.
In another embodiment, which is likewise shown in
In another embodiment, the foil layer 100 is provided with optical information by means of laser structuring, inkjet printing, laser printing, digital printing or screen printing. Preference is given to a printing process such as screen printing, so that the foil layer 100 is a printed foil layer, the printed foil layer 100 has been printed with at least a portion of a two-dimensional projection 500 of the three-dimensionally structured layer 200, and the manner in which the projection 520 of the at least one surface area 230 facing toward the reference location 400 is represented on the printed foil layer 100 differs from the manner in which the projection 530 of the at least one surface area 235 facing away from the reference location 400 is represented.
In another embodiment, where reference can be made to
In the additive CMYK color model, which is used in printing processes, the gray value can be expressed as percentage proportion of the component K (“key”, black). It is preferable that, on the foil layer 100 provided with optical information, the projection 520 of the at least one surface area 230 which faces toward the reference location 400 has a lower gray value in the CMYK color model than the projection 530 of the at least one surface area 235 which faces away from the reference location 400. In the simplest way of analogy described above, “hillsides” facing away from the light source are depicted as darker than those “hillsides” that face toward the light source.
In another embodiment, where reference can likewise be made to
In another embodiment, where reference can likewise be made to
The function in the two last-mentioned embodiments can by way of example be, mutually independently, a linear function or a logarithmic function. A logarithmic function is advantageous for reflecting the logarithmic character of sensory perceptions in humans.
In another embodiment, which is depicted in
In another embodiment, the thermoplastic polymer of which the three-dimensionally structured layer 200 is composed is a polycarbonate. This term also covers copolycarbonates and polycarbonate blends. The melt flow rate MVR of the polycarbonate can be 8 to 20 cm3/(10 min), determined in accordance with ISO 1133-1:2012-03 (300° C., 1.2 kg). Preference is given to 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-2H-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 of bisphenol A and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, or a mixture of at least two of the abovementioned polymers. The polycarbonate can, of course, comprise additives such as dyes, stabilizers, impact modifiers and the like.
The foil layer 100 preferably comprises one or more thermoplastic polymers. Examples have already been mentioned above. In another embodiment, the foil layer 100 provided with optical information comprises a polycarbonate. This term also covers copolycarbonates and polycarbonate blends. The melt flow rate MVR of the polycarbonate can be 8 to 20 cm3/(10 min), determined in accordance with ISO 1133-1:2012-03 (300° C., 1.2 kg). Preference is given to 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-2H-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 of bisphenol A and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, or a mixture of at least two of the abovementioned polymers. The polycarbonate can, of course, comprise additives such as dyes, stabilizers, impact modifiers and the like.
In another embodiment, the first additional layer 300 and/or the second additional layer 310 is/are composed of a two-component lacquer (2C lacquer), of a coextruded foil or of a scratch-resistant-coated foil. It is preferable that the scratch-resistant-coated foil is a polycarbonate foil provided with a coating comprising silicon oxide nanoparticles.
In another embodiment: the thickness of the foil layer 100 provided with optical information is ≥100 μm bis ≤1000 μm (preferably ≥175 μm to ≤500 μm, more preferably ≥250 μm to ≤375 μm), and/or the maximal thickness of the three-dimensionally structured layer 200 is ≥1.5 mm to ≤6 mm (preferably ≥2 mm to ≤5 mm, more preferably ≥3 mm to ≤4 mm)
The layer arrangement of the invention can be used as decorative component or as decorative screening panel. Preferred application sectors are exterior or interior components of vehicles.
A process for the production of a layer arrangement of the invention comprises the following steps:
The principles of the embodiments mentioned in connection with the subject matter of the invention can, of course, also be applied to the process. The optical information on the foil 100 can therefore preferably be produced by printing, and the foil 100 is preferably bonded to the layer 200 in a manner such that the projection of the 3D structure is congruent with the structured side 220.
| Number | Date | Country | Kind |
|---|---|---|---|
| 19169559.2 | Apr 2019 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2020/060121 | 4/9/2020 | WO | 00 |
