Patent Application
20050194825
This application corresponds to German applications 10 2004 008 205.7 filed 18 Feb. 2004 and 10 2004 055096.4 filed 15 Nov. 2004 under 35 USC 119 and the International Convention.
The invention relates to a skin-like covering for vehicle interiors, arm rests, central consoles, door covering, instrument panels and the like.
The invention also relates to a method of making such a covering.
It is known to provide especially the interior spaces of motor vehicles, like, for example, arm rests, central consoles, door linings, instrument panels and other covered parts which may be found in the interiors of automobiles, with a skin-like covering. Such a skin-like covering should satisfy the aesthetic and tactile requirements of the vehicle user. Thus the surface of such a skin-like covering with an appropriate color or with a special structure, for example with a leather structure, should be capable of positively influencing the value of the vehicle from a visual point of view for the vehicle user.
From the tactile point of view, the skin-like covering should provide the vehicle user with a pleasant touch and grip, that is provide desirable properties upon contact of the person of the user with the covering and the pressure of the covering against the person.
A skin-like covering known from DE 38 75 029 T2 in accordance with the principles described at the outset, can comprise a monostructured PUR polyurethane layer which is applied as a liquid reaction mixture in the form of a sprayed skin of a gel with droplets of different sizes. The known skin-like coverings, however, were susceptible of improvement in that they were of limited versatility and involved a high cost of materials.
It is the object of the invention, using as a starting point the above-described covering, to so improve the known covering that with respect to its structure, it will offer greater versatility in form and can be produced more economically.
Another object of the invention is to provide a method of making the improved covering.
These objects are achieved in accordance with the invention with at least two layers, namely by one outer-surface-forming and at least single-layer laquer coating comprising color pigments and by an at least single-layer support coating lying behind the laquer coating, whereby the laquer coating or layer and the support coating or layer each are formed from a reactive polymeric single-component or multicomponent aqueous dispersion with a respective cross-linker or cross-linking agent.
The skin-like covering according to the invention has the following significant elements:
The skin-like covering is comprised of at least two layers, namely from an outer-surface-forming at least single-layer laquer coating or layer and from an at least single-layer support coating or layer carrying the laquer layer or coating.
The subdivision of the covering skin according to the invention into an outer laquer layer and a support layer lying therebeneath from the outset affords a substantially greater range of variations in applications. Thus, for example, with the use of a unitary support or carrier layer relative to the laquer layer alternatively usable and optionally selectable color tones can be employed. Additional variation possibilities arise for different purposes or uses by the provision of carrier or support layers of different compositions.
In contradistinction to the previously known spray skin according to DE 38 75 029 T2 which has a single composition over the entire thickness of the layer forming the skin, with the invention the more expensive components like the color pigments can be limited to the relatively thin laquer layer while the carrier or support layer deals with the strength and thus allows the cost of materials to be reduced.
The laquer layer can be comprised of a single-component or multicomponent material composition.
Thus the laquer layer can be formed from a reactive aqueous polymer dispersion. By the choice of different components of the composition, the laquer layer can, for example, be given a smooth feel, a dry feel or both or some other response to touch.
In a further feature of the invention, the laquer layer is comprised of an acrylate or a polyacrylate and a cross-linking agent. As the cross-linking agent, for example, an isocyanate or carbodiimide or preferably a polycarbodiimide can be used.
The laquer layer has a compact structure. The laquer layer can be applied by entrainment in a pressurized gas and/or in compressed air, that is, sprayed onto a surface. With this finest gas-supported or compressed-air-supported atomization, the droplet size of the reactive aqueous polymeric dispersion can be about 5μ to 100μ, preferably about 30μ to about 60μ.
The laquer layer can be a single layer or can be composed of a plurality of layers.
The thickness of the laquer layer can amount to between 10μ and 300μ, preferably between 60μ to 90μ.
The very fine gas-supported or air-supported atomization of the reactive aqueous polymeric dispersion for the laquer layer results in a homogeneous and bubble-free surface which, conditioned upon the spraying onto an engraved form (engraved surface of a tool) will reproduce the engraving, that is its texture or graining, free from defects.
In addition the invention can apply the laquer layer in a plurality of colors adjacent one another, whereby effect lacquering is possible.
The colors or color tones of each laquer layer can be adjusted by the addition of corresponding coloring pigments.
Further, the invention provides that the laquer layer can contain material components which are known in the art and which have a light-stabilizing effect.
In a further feature of the invention, the carrier or support layer is comprised of a polymeric elastomer layer which is also produced from an aqueous dispersion. This dispersion is comprised, according to the invention, of a reactive aqueous PUR dispersion. The carrier or support layer contains as the cross-linking agent also an isocyanate or carbodiimide or, preferably, a polycarbodiimide. As has already been indicated, the carrier or support layer bestows the strength to the covering skin.
The carrier or support layer also can, corresponding to the invention, be formed as a single layer or as a plurality of layers from a single-component or a multicomponent material composition. The thickness of the carrier or support layer can amount preferably to about 0.3 mm to about 1.0 mm.
The carrier layer or support layer, according to the invention, is also sprayed with the aid of pressurized gas or compressed air. By means of the very fine gas-supported or air-supported atomization, a droplet size of about 5μ or 100μ, preferably from about 30μ to 60μ is produced.
The carrier layer or support layer of the covering skin can have a PUR foam-backed carrier which itself can be backed by a suitable moldable or pressable mass so that the laquer layer, carrier or support layer and PUR form can form the covering with its high quality surface.
The invention is comprised, in addition, of a method of making a skin-like covering, especially for automotive vehicle interior parts, like arm rests, central consoles, door coverings; instrument panels or the like of automobiles, in which at least one color-pigment-containing liquid polymer reaction mixture is applied to a shape-imparting surface of a tool. A process of this type is known from DE 38 75 029 T2.
The method according to the invention differs from that process in that initially a laquer layer formed from a cross-linker containing reactive polymeric aqueous single-component or multicomponent dispersion is sprayed in one or more layers onto an engraved surface of optional shape and surface contour, like for example, a leather graining, and then a support layer is applied to the back side of the lacquer layer in one or more layers of a cross linker containing reactive polymeric aqueous single-component or multicomponent dispersions, whereby both the lacquer layer and the support layer are deposited by means of pressurized gas and/or by means of compressed air.
Both the application of the lacquer layer and the application of the support or carrier layer take place with a variably adjustable metering of the material, with a variably adjustable atomization of the material, with a variably adjustable spray jet configuration and with a variably adjustable spray jet deflection.
The material temperature both for the lacquer layer dispersion and also the support layer dispersion amounts preferably to 20° C. to about 120° C.
Both the lacquer layer and the support or carrier layers can be one-component or multicomponent compositions.
The lacquer layer and the support or carrier layer are sprayed one after the other onto a shape-forming engraved surface. The engraved surface can for example be a temperature-controlled shell, preferably of metal, like, for example, of aluminum, steel or nickel. It has also been found to be advantageous to heat the shell, that is the engraved surface, to an operating temperature of about 120° C.
The method of the invention can be used to form simple contours, for example planar contours and contours with simple geometry as well as complex, undercut contours.
From the point of view of the device for practicing the method according to the invention, the nozzle spray head can be moved with respect to the shape-forming engraving or, conversely, the shape-forming engraving can be moved with respect to the nozzle spray head.
For producing undercut surfaces, it has been found to be advantageous to be able to move the nozzle spray head with all possible degrees of freedom of movement in space relative to the layer receiving surface.
The nozzle spray head is advantageously configured as a two-material or two-component spray head for atomizing the aqueous dispersion with pressurization gas or compressed air.
In the drawing, both the covering skin as well as the device with its associated method are schematically illustrated by way of example. In the drawing:
In
The lacquer layer 11 is composed of a reactive aqueous polymeric dispersion which contains acrylate or polyacrylate and as a cross linking agent or cross-linker a carbodiimide or polycarbodiimide. The thickness of the lacquer layer 11 amounts to about 100μ.
The support layer 12 is composed of a reactive aqueous PUR dispersion which also contains carbodiimide or preferably polycarbodiimide as the cross-linker.
The lacquer layer 11, especially, contains the requisite color pigments.
The support layer has a thickness between 0.3 and 1 mm.
The support or carrier layer 12 is backed by the PUR foam layer 13 which is a multiple of the thickness of the support or carrier layer 12. All of the layers 11, 12, 13 cover the shape-determining support part 14 of the covered member 10. The support part 14 can for example be an injection molded part of plastic, a blow molded part or a part made by pressing.
In
A mold 15, for example of a chromium-nickel steel or of aluminum, with an undercut mold cavity 16 has in cross section generally polygonal like engravings (engraved surface) 17 extending thereon. The engraving 17 can have a surface structuring, for example a leather-like graining. The mold 15 is advantageously heatable in a manner not shown, for example, by means of electric heating cartridges or by means of passages through which a heating liquid can be passed. In this manner an operating temperature of for example 80 EC can be provided. An appropriate nozzle spray head 18 extends into the mold cavity 16 and has been shown schematically and can produce a spray supported by pressurized gas and/or compressed air of the respective active aqueous polymer dispersions for the layers 11 and 12.
The nozzle spray head 18 should be movable in space with all possible degrees of freedom corresponding to the arrows a, b and c. In this manner, even with undercuts it is possible to initially deposit the lacquer layer 11 and then the support layer 12 of the covering skin represented as a whole at H in the mold 15 by atomizing the respective dispersion.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102004008205.7 | Feb 2004 | DE | national |
| 102004055096.4 | Nov 2004 | DE | national |
