Abrasion-Resistant Wood Board

Abstract

An abrasion-resistant wood-based panel having a top side and a bottom side, with at least one decorative layer arranged on the top side, in particular with a structure synchronous with the decoration, is disclosed herein.

Claims

1. A wood-based panel with at least one decorative layer arranged on the upper side, in particular with a structure synchronous with the décor with the following layer structure, viewed from bottom to top: a backing layer of six layers of resin; a wood-based panel; a primer layer; a print decoration layer; a protective layer; a first resin layer with cellulose fibres; a layer of abrasion-resistant particles; a second resin layer; a third resin layer with glass beads; a fourth resin layer with glass beads; a fifth resin layer with glass beads; and a sixth resin layer without glass beads, wherein the multilayer resin structure has a total layer thickness between 120 and 200 μm, preferably between 150 and 200 μm, and wherein the amount of abrasion-resistant particles is 10 to 50 g/m.sup.2, preferably 10 to 30 g/m.sup.2, more preferably 15 to 25 g/m.sup.2.

2. The wood-based panel according to claim 1 with markings in the decorative layer for aligning the wood-based panel in the press, in particular to a structured press sheet located in the short-cycle press.

3. The wood-based panel according to claim 1, wherein the protective layer consists of a not yet fully cured resin.

4. The wood-based panel according to claim 1, wherein the resin layers are based on aqueous formaldehyde-containing resins, in particular melamine-formaldehyde resin, urea-formaldehyde resin or melamine-urea-formaldehyde resin.

5. The wood-based panel according to claim 1, wherein the first, second and third resin layers each have a solids content of between 60 and 80% by weight, preferably between 65 and 70% by weight, more preferably between 65 and 67% by weight.

6. The wood-based panel according to claim 1, wherein the fourth, fifth and sixth resin layers each have a solids content of between 50 and 70% by weight, preferably 55 and 65% by weight, more preferably between 58 and 62% by weight.

7. The wood-based panel according to claim 1, wherein the abrasion-resistant particles are corundum particles.

8. The wood-based panel according to claim 1, wherein the glass spheres have a diameter of 90 to 150 μm.

9. The wood-based panel according to claim 1, wherein the amount of glass beads is 10 to 50 g/m.sup.2, preferably 10 to 30 g/m.sup.2, more preferably 15 to 25 g/m.sup.2.

10. The wood-based panel according to claim 1, with an abrasion value in the abrasion classes AC4 to AC6.

11. The wood-based panel according to claim 1, wherein the amount of cellulose fibres in the first resin layer is between 0.1 and 1 wt %, preferably between 0.5 and 0.8 wt %, based on the amount of resin to be applied, or between 0.1-0.5 g/m.sup.2, preferably 0.2-0.4 g/m.sup.2, more preferably 0.25 g/m.sup.2.

12. The wood-based panel according to claim 1, wherein the wood-based panel is a medium-density fibre (MDF), high-density fibre (HDF) or chipboard or rough chipboard (OSB) or plywood panel and/or a wood-plastic panel.

13. A production line for manufacturing a wood-based panel according to claim 1 comprising the following elements: at least a first application device for applying a first resin layer, which may contain fibres, to the upper surface of the wood-based panel; at least one device arranged downstream of the first application device in the processing direction for scattering a predetermined amount of abrasion-resistant particles; at least one second application device arranged behind the first application device and scattering device in the processing direction for applying a second resin layer to the upper side of the wood-based panel; at least one drying device arranged behind the second application device in the processing direction for drying the layer structure of first and second resin layer; at least one third application device arranged downstream of the drying device in the processing direction for applying a third resin layer containing glass beads to the upper side and/or a resin layer in parallel to the lower side of the carrier plate; at least one further drying device arranged behind the third application device in the processing direction for drying the third upper and/or corresponding lower resin layer; at least one fourth application device arranged downstream of the further drying device in the processing direction for applying a fourth resin layer containing glass beads to the upper side, and/or a resin layer in parallel to the lower side of the carrier plate, without glass beads; at least one drying device arranged behind the fourth application device in the processing direction for drying the fourth upper and/or corresponding lower resin layer; at least one fifth application device arranged downstream of the drying device in the processing direction for applying a fifth resin layer containing glass beads to the upper side and/or a resin layer in parallel to the lower side of the carrier plate, without glass beads; at least one drying device arranged downstream of the fifth application device for drying the fifth upper and/or corresponding lower resin layer; at least one sixth application device arranged downstream of the drying device in the processing direction for applying a sixth resin layer to the upper side and/or a resin layer in parallel to the lower side of the carrier plate; at least one drying device arranged downstream of the sixth application device in the processing direction for drying the sixth upper and/or corresponding lower resin layer; and at least one short-cycle press arranged downstream of the last drying device in the processing direction.

14. The wood-based panel according to claim 2, wherein the protective layer consists of a not yet fully cured resin.

15. The wood-based panel according to claim 2, wherein the resin layers are based on aqueous formaldehyde-containing resins, in particular melamine-formaldehyde resin, urea-formaldehyde resin or melamine-urea-formaldehyde resin.

16. The wood-based panel according to claim 3, wherein the resin layers are based on aqueous formaldehyde-containing resins, in particular melamine-formaldehyde resin, urea-formaldehyde resin or melamine-urea-formaldehyde resin.

17. The wood-based panel according to claim 2, wherein the first, second and third resin layers each have a solids content of between 60 and 80% by weight, preferably between 65 and 70% by weight, more preferably between 65 and 67% by weight.

18. The wood-based panel according to claim 3, wherein the first, second and third resin layers each have a solids content of between 60 and 80% by weight, preferably between 65 and 70% by weight, more preferably between 65 and 67% by weight.

19. The wood-based panel according to claim 4, wherein the first, second and third resin layers each have a solids content of between 60 and 80% by weight, preferably between 65 and 70% by weight, more preferably between 65 and 67% by weight.

20. The wood-based panel according to claim 2, wherein the fourth, fifth and sixth resin layers each have a solids content of between 50 and 70% by weight, preferably 55 and 65% by weight, more preferably between 58 and 62% by weight.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0101] The solution is explained in more detail below with reference to the FIGURES in the drawings, using an example of an embodiment.

[0102] FIG. 1 shows a schematic representation of a production line of a wood-based panel using the method according to the proposed solution.

DETAILED DESCRIPTION OF THE INVENTION

[0103] The production line shown schematically in FIG. 1 includes an IR dryer 1a which is switched off. Removal of the IR dryer 1a from the production line avoids the electrostatic charging of the plate surface that would otherwise take place in the IR dryer, which makes it possible to form a homogeneous scattering curtain of corundum.

[0104] The production line further comprises a single-sided applicator unit 1 (grooved roller), and five double applicator units 2, 3, 4, 5, 6 for simultaneous application of the respective resin layer to the upper side and the lower side of the separated printed material boards, e.g. of printed HDF boards, as well as four convection dryers 2a, 3a, 4a, 5a, 6a arranged behind each of the applicator units in the processing direction.

[0105] Downstream of the first applicator roll 1, a first scattering device 20 is provided for uniformly scattering the abrasion-resistant material such as corundum onto the first resin layer on the top side of the HDF board. The abrasion resistant material used is F200 corundum, which measures about 53-75 μm in diameter according to FEPA standards. The scattering device 20 essentially consists of a supply hopper, a rotating, structured spiked roller and a scraper. The application rate of the material is determined by the rotational speed of the scattering roller. Depending on the required abrasion class of the product, between 12-25 g/m.sup.2 of corundum is scattered onto the resin-coated board (AC4 (according to EN 13329)=20 g/m.sup.2). From the spiked roller, the corundum falls onto the melamine resin treated board at a distance of 5 cm. Since the first resin layer is still liquid at the time of scattering, the abrasion-resistant particles can sink into the resin layer. Under the present scattering device, at least one hopper (not shown) is provided in front of the scattering roller for collecting excess abrasion-resistant particles (i.e., abrasion-resistant particles not scattered on the at least one wood-based panel, but rather falling down in front of the wood-based panel before the wood-based panel is moved in by means of the transport device under the scattering roller).

[0106] In the double-sided coating unit 2, the board coated with melamine-formaldehyde resin and corundum is coated with further melamine-formaldehyde resin (about 20 g/m.sup.2). At the same time, the unattached corundum is removed in small amounts and accumulates in the melamine resin liquor until saturation (about 10 wt. %) occurs. This lost portion of the corundum is now continuously reapplied to the board by the roller application of coating unit 1-1. The second application covers the corundum grains with liquid resin or incorporates them into the overlay layer. This prevents the corundum from being removed in the convection dryer due to the high air turbulence.

[0107] The build-up of first and second resin layers is dried in convection dryer 2a.

[0108] Downstream of the third double coater 3 for applying the third resin layer, there may be another scattering device 20 for applying glass beads to the third resin layer followed by a third convection dryer 3a for drying the third resin layer. The scattering device 20 for the glass beads is optional. The glass beads may also be applied together with the third resin layer.

[0109] After application of the fourth to sixth resin layers in a fourth to sixth double coater 4, 5, 6 and drying in a convection dryer 4a, 5a, 6a respectively, the layer structure is cured in a short-cycle press 7 at a pressing temperature of 180-220° C. and a pressing time of 8 to 10 seconds under a specific pressure of 40 kg/cm.sup.2. The pressed sheets are cooled and stored.

[0110] While this disclosure has been described as having exemplary designs, the present disclosure can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the limits of the appended claims.