Coated panel and method for manufacturing a coated panel

Abstract

The present invention relates to a method for the manufacturing of a coated panel, in particular a wall, ceiling or flooring panel for applications in outdoor areas, as well as such a panel. The method comprises the following steps: providing a carrier plate of mineral wool and/or glass wool, comprising a front side and a rear side, applying a primer onto the front side of the carrier plate, thereafter applying a liquid first oligomer in an amount of 30 to 150 g/m.sup.2 onto the front side of the carrier plate; thereafter applying a liquid second oligomer, which differs from the first oligomer, in an amount of 30 to 180 g/m.sup.2 onto the wet surface of the before applied layer of the first oligomer.

Claims

1. A method for the manufacturing of a coated panel, in particular a wall, ceiling or flooring panel for applications in outdoor areas, comprising the following steps: a) providing a carrier plate of mineral wool and/or glass wool, having a major front surface and a rear surface; b) applying a primer onto the major front surface of the carrier plate; wherein the primer comprises isocyanates; c) thereafter, applying a liquid first oligomer in an amount of 30 to 150 g/m.sup.2 onto the front major surface of the carrier plate; d) thereafter, applying a second liquid oligomer, which is different from the first oligomer, in an amount of 30 to 180 g/m.sup.2 onto the wet surface of the first oligomer layer applied in step c); and e) thereafter, curing of the applied oligomers.

2. The method according to claim 1, wherein the first oligomer is applied in step c) in two or more partial steps.

3. The method according to claim 1, wherein step c) in a first partial step, the first oligomer is applied in an amount of 30 to 100 g/m.sup.2, this amount is slightly gelled and in a second partial step, another 10 to 50 g/m.sup.2 of this first oligomer is applied, onto the slightly gelled surface of the oligomer that was applied in the first partial step.

4. The method according to claim 1, wherein the first oligomer is a polyurethane acrylate, respectively based thereon.

5. The method according to claim 1, wherein the second oligomer is composed of the same chemical compounds as the first oligomer, however, in a different mixture, so that after curing the second oligomer has a greater hardness than the first oligomer.

6. The method according to claim 1, wherein the isocyanates comprise aliphatic or cyclo-aliphatic compounds, di- and polyisocyanates with an NCO functionality of at least 1.8 and/or the corresponding isocyanurates, biuretes, allophanates and uretdiones.

7. The method according to claim 1, wherein the primer comprises isocyanates and alkyl methacrylates.

8. The method according to claim 1, wherein the cured oligomer layers have a tensile strength of 3 to 30 N/mm.sup.2.

9. The method according to claim 1, wherein the cured oligomer layers comprise a Young's modulus of 400 to 3000 N/mm.sup.2.

10. The method according to claim 1, wherein the oligomers comprise at least one photo initiator.

11. The method according to claim 1, wherein the carrier plates are provided on their sides with coupling means in the form of groove and tongue elements, which allow a connection of several identical panels in directions parallel to the major front surface as well as perpendicular to the major front surface by means of a form fitting connection.

12. The method according to claim 1, wherein after step b), but for before step c), a decor layer is printed onto the major front surface of the carrier plate.

13. The method according to claim 1, wherein the carrier plate has a thickness between 3 and 20 mm.

14. The method according to claim 1, wherein the application in step c) is done by rollers and in step d) is done by curtain coating or by spraying.

15. The method according to claim 1, wherein the first oligomer is applied in an amount of 30 to 150 g/m.sup.2.

16. The method according to claim 1, wherein the second oligomer is applied in an amount of 30 to 180 g/m.sup.2.

17. The method according to claim 1, wherein the primer is applied in an amount of 3 to 300 g/m.sup.2.

18. A panel obtainable by a process in accordance with claim 1.

19. A panel, in particular wall, ceiling or flooring panel for applications in outdoor areas, comprising a carrier plate of mineral wool and/or glass wool, having a front major surface and a rear surface, whereby the front major surface comprises a layer system having the following layers in the given order as seen from the carrier plate: a) a primer layer based on isocyanate; b) a first layer based on a first cured oligomer; c) a second layer based on a second cured oligomer, which differs from the first oligomer.

20. The panel according to claim 19, wherein the first oligomer is a polyurethane acrylate.

21. The panel according to claim 19, wherein the second oligomer consists of the same chemical compounds as the first oligomer, however, in a different mixture, so that the second oligomer has a greater hardness as the first oligomer, when cured.

22. The panel according to claim 19, wherein the isocyanate comprises aliphatic or cyclo-aliphatic compounds, di- and polyisocyanates with an NCO functionality of at least 1.8, and/or the corresponding isocyanurates, biuretes, allophanate and uretdiones.

23. The panel according to claim 19, wherein the primer comprises isocyanates and alkyl methacrylates.

24. The panel according to claim 19, wherein the oligomer layers after curing have a tensile strength of 3 to 30 N/mm.sup.2.

25. The panel according to claim 19, wherein the cured oligomer layers comprise a Young's modulus of 400 to 3000 N/mm.sup.2.

26. The panel according to claim 19, wherein the oligomers comprise at least one photo initiator.

27. The panel according to claim 19, wherein the carrier plate is provided on its sides with coupling means in the form of groove and tongue elements, which allow a coupling of several identical panels in directions parallel to the major front surface as well as perpendicular to the major front surface by means of a form fitting connection.

28. The panel according to claim 19, wherein the carrier plate has a thickness between 3 and 20 mm.

Description

4. DESCRIPTION OF PREFERRED EMBODIMENTS

(1) In the following the present invention is described in more detail under reference to the enclosed figures.

(2) FIGS. 1 and 2 show exemplary layer arrangements in a schematic illustration; and

(3) FIG. 3 shows an exemplary facility for manufacturing an inventive panel in a schematic illustration.

(4) In FIG. 1, a schematic layer structure for a panel 1 according to the invention is shown. The illustration is purely schematic and not up to scale. In particular, the carrier plate 10 is substantially thicker than the further layers 4, 12, 13 and 14, which are, for example, in the range of several hundred μm. The panel 1 can in addition comprise further layers, as in particular base coatings, a decor layer as well as eventually a primer layer for the decor layer and others.

(5) In the shown example, the carrier plate 10 is provided with a thickness of approximately 8 mm and is made from mineral wool. On the rear, respectively back major surface of the carrier plate 10, a moisture barrier 4 in the form of a suitable plastic foil is applied. The moisture barrier is optional and depends on the material for the carrier plate 10 and the intended use. The carrier plate 10 further comprises coupling means in the form of groove 3, respectively tongue elements 2, which are only sketched in the figures. Suitable coupling means in the form of groove and tongue elements that allow a connection of several identical panels in directions parallel to the major front surface as well as perpendicular to the major front surface by means of form fitting are known to the skilled person, for example from the field of laminate floorings. It is referred for the details of such coupling means exemplarily to WO 0188306 or WO 0148332 of the same applicant, which contents are herewith incorporated by reference.

(6) In the example of FIG. 1 onto the major front surface of carrier plate 10 a primer 12 was applied. Onto this primer a first layer of the liquid oligomer 13 was applied in an amount of 30 to 150 g/m.sup.2. Above this first layer 13, a second layer 14 of a second oligomer is arranged, which is different from the first oligomer. Also this second layer 14 was applied in an amount of 30 to 150 g/m.sup.2. Both layers 13 and 14 were applied wet on wet, so that at the border surface between both layers the two liquid base materials were partially mixed. The composition in this border region of both layers 13 and 14 is thus different to the composition of the base materials of layers 13 and 14.

(7) In FIG. 2, a modified panel 1′ is shown, wherein in contrast to panel 1 the application of the layer of the first oligomer is done in two partial steps. Thereby, in a first partial step, a first layer 13.1 is applied in an amount of 30 to 100 g/m.sup.2. This applied substance was slightly gelled and after that in a second partial step, the rest of the first oligomer was applied as layer 13.2 onto the slightly gelled (not fully cured) surface of layer 13.1. Therefore, no mixture occurs between both layers 13.1 and 13.2. In the example of FIG. 2 in a next step, a second oligomer was applied onto the still wet layer 13.2 in the form of layer 14. At the border region between layer 13.2 and layer 14, a partial mixture of both layers occurred, since layer 13.2 was not slightly gelled. After application of layer 14, the whole layer system is preferably fully cured by means of radiation.

(8) In the following, the manufacturing of an inventive panel is exemplarily described under reference to FIG. 3. FIG. 3 shows schematic a facility for the coating of carrier plates 10. The carrier plates are further processed after the coating in a separate cutting line (not shown) and provided with coupling means, i.e. with a suitable coupling profile, in particular with groove and tongue elements. The carrier plates 10 are based on mineral wool and have, for example, a thickness between 3 and 20 mm, a length (as seen in the transport direction of the facility of FIG. 3) of 150 to 200 cm and a width of 125 to 210 cm. However, also other dimensions for the carrier plates can be used, which are then cut into the desired form and shape at the end of the process. The stations shown in FIG. 3 of the facility are only exemplarily for the description of the inventive method and additional stations may be added as necessary. For example, before, after and between the shown stations additional processing stations may be provided, as in particular additional drying stations, stations for the application of primers, stations for the application of base coatings, control and monitoring devices, printing devices for application of a decor, etc.

(9) The carrier plates 10 are transported through the coating facility by means of roll conveyors 31. At the first station 312 shown, a primer 12 is applied by means of a liquid curtain onto the major front surface of the carrier plates 10. The liquid curtain of the primer extends over the whole width of the plates and the plates are transported through this curtain and thereby coated with the primer. Underneath the station 312 for the application of the curtain, a container 23 is arranged, into which the liquid curtain falls, when no plate is transported through the curtain, as it, for example, occurs with the gaps between two successive plates.

(10) In step 33 the primer is dried, for example by means of hot air. In station 313 onto the fully or partially dried primer 12 a first layer 13 of a first oligomer is applied in an amount of 30 to 150 g/m.sup.2 onto the major front surface of carrier plate 10. The carrier plate is thereafter transported with the layer 13 of the first oligomer without any subsequent drying or curing. In a further station 314 an additional layer 14 of a liquid, second oligomer is applied onto the still wet surface of layer 13 of the first oligomer by means of, for example, a curtain coating. The second oligomer differs from the first oligomer and is likewise applied in an amount of 30 to 150 g/m.sup.2. Finally, at station 3 or 4, the layers of the still wet oligomers are cured, preferably by means of radiation.