Patent Application
20050193677
The present application claims priority under 35 U.S.C. ยง119 of German Patent Application No. 10 2004 011 531.1, filed on Mar. 8, 2004, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention
The invention relates to a wooden material board, in particular a flooring panel, having a tongue formed on at least one side edge and a groove formed on the opposite side edge, and a top side and an underside.
2. Discussion of Background Information
Flooring panels having a wooden material supporting board are normally designated laminate panels and have been on the market for many years as a substitute for parquet. The desired pattern (parquet, wood grain, tiles and so on) is printed onto a paper web, which is then coated with resin and rolled up onto a roll. The decorative web prefabricated in this way is placed on the supporting board at the flooring manufacturer and is pressed. As a result of pressing the pattern onto the paper web, the subsequent sealing of the paper web with synthetic resin and the following joining of the decorative layer to the supporting board by pressure and temperature, the dimensions of the paper web change. Those skilled in the art speak of the paper growing. The paper grows both in terms of length (length growth) and in terms of width (width growth). If this decorative board is now to be cut to size to form individual panels, the length and width growth must be taken into account, since otherwise there would be an unequal distribution of decoration on the individual panels. The consequence of this would be that the floor composed of unequally distributed decorative layers would exhibit jumps in the decoration at the joining edges of the panels. Even if such jumps in the decoration only amount to a few millimeters, they stand out when viewed, which has a detrimental influence on the esthetic impression and therefore reduces the quality of the laid floor.
In order to be able to produce with a suitable quality, the paper growth must be registered and the saw which cuts the panels to shape from the supporting board must be set appropriately. Manual setting is very complicated. DE 100 19 054 describes a method of cutting panels to size from a supporting board, with which the saw can be adapted automatically to the paper growth. Cameras are needed for this purpose, which determine the actual position of defined decorative points. The actual position is therefore compared with the desired position and the deviation of the width or length dimension is determined, so that the saw can be set appropriately.
The soundproofing qualities of laminate panels are poorer as compared with parquet. In order to reduce the development of noise when the flooring is walked on, either insulating mats of plastic are laid on the subfloor, onto which the panels are then laid, or an insulating layer is already applied to the underside of the supporting board at the factory.
As a result of the necessary insulating layer, firstly the structure of the flooring becomes thicker. For the purpose of subsequent laying of rooms with laminate panels (for example as a replacement for carpets), however, it is desirable if the panels are thin. Secondly, applying the insulating layer to the underside of the supporting board requires a further operation and additional material, which increases the manufacturing costs. Laying an insulating film on the subfloor must be carried out very carefully in order to lead to the effective damping of footfalls.
Starting from this problem, the wooden material board described at the beginning is to be improved.
The solution to the problem in the case of a wooden material board of the generic type is found by the pattern being printed directly onto the top side, a first elastic varnish layer being applied to the decoration and a second varnish layer, which is harder than the first varnish layer, being applied to the first varnish layer.
As a result of this configuration, first of all the paper layer is eliminated. Consequently, the pattern can change neither in length nor in width. The saw with which panels are later cut to size can be preset. By means of the elastic varnish layer which is applied directly to the pattern, footfalls are damped, so that the footfall characteristics are improved. The harder varnish layer applied to the elastic varnish layer prevents wear caused by abrasion or damage to the surface.
Corundum particles can be scattered in the second varnish layer, in order to increase the abrasion resistance of the flooring panel.
If the second varnish layer is inelastic, it is possible to set a surface hardness which corresponds to that of conventional laminate floor panels.
The varnishes of the varnish layers are preferably UV-curable, which means that the fabrication times are shortened.
In order to have the printed decoration act in a brilliant way, the varnish layers are preferably transparent.
A tongue is also preferably formed on a further side edge and a groove on the opposite side edge.
If the tongue and the groove are provided with locking means which prevent displacement transversely with respect to the joining direction in the case of two panels joined to each other, the flooring can be laid in a floating manner without glue.
An exemplary embodiment of the invention is to be described in more detail below with the aid of a drawing, in which:
The flooring panel 7 has a core of wooden material, preferably HDF or MDF. On one longitudinal edge I and one transverse edge III, the panel 7 is provided with a tongue 1, 11 and, on the opposite side edge II, IV, is provided with a groove 2, 12 corresponding thereto. A pattern, for example a wood grain, is printed directly onto the top side 10. An elastic varnish layer 3 is applied to the decoration and this is in turn covered by an inelastic varnish layer 4, into which corundum particles can be scattered. The varnishes of the varnish layers 3, 4 are UV-curable. On the underside 9, if necessary, a counteracting layer is provided (not shown), which prevents the panel (7) bending as a result of the tensile forces occurring because of the varnish layers 3, 4. The tongues 1, 11 are provided with locking means 5, which correspond to the locking means 6 provided in the groove 2 and lock the panels against displacement in the transverse direction.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2004 011 531.1 | Mar 2004 | DE | national |
