EP2179864B1 - Method for finishing a carrier plate - Google Patents

Description

The invention relates to a method for refining a support plate, for example a wood or wood-based panel, in particular MDF or HDF board with a top and a bottom, on the surface of the top of which a plurality of layers of a synthetic resin, preferably melamine resin applied and each layer is dried prior to the application of the next layer, wherein between two layers, a color layer is provided to produce a decoration and the dry layer structure between an upper and a lower pressure plate of a pressing device is pressed under the action of heat and pressure and thereby melt the resin layers. Furthermore, the invention relates to a pressing device.

The method described above is for example from the EP 1 454 763 A2 known. The plates produced by the process are used, for example, for furniture construction. From them, it is also possible to produce panels, in particular floor panels.

Floor panels with a base plate made of wood material are commonly referred to as laminate panels and have been for many years for the substitution of parquet in the trade. To obtain a smooth surface, the surface of the support plate is first ground and then applied a primer of one or more melamine resin layers. On the primer then the desired decor (parquet, wood grain, tiles, etc.) is printed. On the printed decor then a functional layer is applied for sealing the top. If the carrier plate subsequently to be further processed to floor panels, wear-resistant particles, such as corundum, are embedded in the functional layer. Finally, the layer structure is pressed and in the process a structure (relief) corresponding to the decor is embossed in order to match the visual and haptic impression with the natural material reproduced by the decor.

From the WO 2007/059805 A1 is a coating system with flowable coating material for smooth or textured surfaces known. In order to provide the surface of the coating material with a structure, a material web with a structured surface is used. On the input side of the coating system, a carrier material is supplied, which is coated with a flowable material. Below the material web a collecting device is provided, which is funnel-shaped in cross section together with the material web, so that the flowable material can be applied to the carrier plate. While the carrier plate is transported with the overlying web through the device, the coating material hardens and it forms in its surface, the predetermined structure of the material web. The pressing device is very complex. As a coating material expensive UV coatings must be used.

From the DE 26 03 414 A1 is a hot press for surface hardening of wood-based panels known. For this purpose, one or more synthetic resin, for example, melamine resin precondensates enhaltende films are applied to the support plate one or both sides and then pressed in the hot press. The resin cures and the film bonds firmly to the carrier plate. Paper webs can be laid over the press plates, by means of which the structure of the paper webs can be transferred to the surface during the pressing of the wood-based board.

Also from the DE 10 2007 016 794 A1 It is known to impress the structure of a structured paper in the surface of this component for producing a flat component with a structured surface, wherein the structural paper is pressed as a single sheet together with the structurable surface of the component and the sheet format to the format of the structurable surface of the component is adjusted.

It is also known to introduce surface structures in laminated on wood-based panels film packages on texturizer films on rotary presses. Since the film package is already finished, both a high pressure and a high temperature is needed. Since both the applicable pressure and the temperature are limited by the structural design of the circulating press, such systems run only very slowly. The reusable structurizer film survives only a limited number of passes, so that this method is also quite expensive.

Based on this problem, the method described at the outset for refining a carrier plate is to be improved and a press device is to be created with which correspondingly coated carrier plates can be structured quickly and cost-effectively.

To solve the problem, a structured film provided with depressions and / or elevations is arranged below the upper press plate, which ensures that the molten synthetic resin flows smoothly to the depressions and / or elevations of the texturing film, whereby a. After curing of the resin Structure forms, and that the structurizer film is blown off by means of a pulse-like generated by a pneumatic device overpressure of the press plate.

The surface created in this way is characterized by a new visual and haptic impression. The product surfaces are softer or velvety, which is due to the effect of the structurizer film instead of a hard steel pressed sheet. Since the structure is carried out in a short-cycle press by means of the structuring sensor film, the desired structure can be quickly and inexpensively changed or replaced. So it can be made on a pressing device a wide range of products. The fact that the structurizer film is blown off by means of a pulse-like overpressure of the press plate, this is solved quickly and without damage, if it should have been impregnated during pressing with synthetic resin, which then cakes on the underside of the press plate. By loosening the structure-forming film of the press plate is ensured that it can be easily wound to bring a new film under the press plate, without causing the film web breaks. The cycle times are increased significantly. In particular, if the structurizer film is used several times, impregnation with resin is likely.

Preferably, a water-based lacquer enriched with color pigments is used for the color layer.

In order to avoid a subsequent buffing of the support plate or the panels produced therefrom, a counteracting layer is preferably applied to the underside prior to pressing.

As the first layer, a liquid melamine resin is applied to the preferably previously ground top side. In particular, a primer layer can then be applied to the dried melamine resin layer. A pressing device for pressing and structuring carrier plate provided with a plurality of resin layers with an upper pressure plate and a lower pressure plate is characterized in that a patterning foil provided with depressions and / or elevations is to be arranged below the upper pressure plate.

The texturizer film is preferably applied to the press plate. In particular, it is preferably fixable to the pressing plate, which can be done for example by suction, electrostatic charging or adhesion.

Preferably, an unwinding device is arranged on one side next to the upper press plate, and a winding device for the texturing film is arranged on the opposite side. On the structure-forming film, the structure matching the printed decor is embossed in each case in the associated plate size. The structure can be repeated on the foil tape. However, it is also possible for different structures to be provided one behind the other (in each case in plate size) on the structure-forming film.

Preferably, the upper pressure plate has a press plate provided with a plurality of openings, and the openings communicate with a pneumatic device. In order to remove the shear modifier foil which bears against the press plate, the pneumatic device preferably generates an overpressure in a pulse-like manner, which blows off the texturizer foil from the press plate.

From the pneumatic device, a negative pressure for sucking the pattern generator film can be generated. Preferably, the structurizer film then completely covers the openings in the press plate.

With the aid of a drawing, an embodiment of the invention will be explained in more detail below.

The single FIGURE shows schematically the side view of a short-cycle press (KT-press) with the upper pressure plate 1 and the lower pressure plate 11. The upper pressure plate 1 consists of the upper frame 2, the press pad 3 and the press plate 4. Die on a press table 12th arranged lower press plate 11 consists of the base 13, the press pad 14 and the press plate 15th

The lower press plate 11 is rigid. About the impression cylinder 5, the upper pressure plate 1 can be lowered to the lower pressure plate 11 and pressurized. The press plates 1, 11 are heated by thermal oil in a known manner. On the press plate 4, which is provided with a plurality of openings, not shown, is applied to the structure sensor film 9, in which a structure is impressed. The openings in the press plate 4 are connected to a both negative pressure and positive pressure generating pneumatic device 50 in connection. On both sides next to the upper pressure plate 1, an unwinding device 6 and a winding device 10 are arranged opposite one another. The structuring film 8 is unwound from the unwinding device 6 and simultaneously wound up by the winding device 10. About deflection rollers 7, 9, the Strtikturgeber film is guided below the press plate 1. When the pneumatic device 50 generates negative pressure, the structuring film 9 is sucked onto the press plate 4. For releasing a Druckluftstaß is generated via the pneumatic device 50, which blows the structure-sensor film 8 from the press plate 4.

To smooth the surface, the large-format support plate, for example an MDF or HDF plate, is abraded by 0.1 mm. Then, melamine-based liquid resin is applied to the top for priming and dried to the layer 101. On the dried melamine resin layer 101, a primer is applied and dried.

Subsequently, a layer 102 enriched with color pigments, water-based paint is applied and thus generates the decorative layer, which is then dried. Then at least one functional layer 103 is applied as a seal of the upper side. In the functional layer 103, it is possible to integrate the abrasion and / or the scratch-resistance-increasing particles. The functional layer 103 can also be formed antistatic. To compensate for the effect of the layer structure 101, 102, 103 on the upper side of the carrier plate 100, at least one counter-tensile layer 104 is applied to its underside and dried. Subsequently, the carrier plate 100 is transported into the short-cycle press and placed on the lower press plate 11. The structure of the structure-donor sheet 8 corresponding to the decor of the decoration layer 102 is selected and then pulled under the upper press plate 1 by driving the take-up device 10. In this case, the structure sensor film 8 is wound from the unwinding device 6. The structuring film 8 is sucked onto the press plate 4 and then the upper press plate 1 is lowered onto the carrier plate 100. Due to the heat and the pressure, the resin layers melt and the liquid resin runs into the recesses or fills the gaps between the elevations of the structuring film 8, so that after curing of the resin, a structure corresponding to the decoration in the surface of the Carrier plate 100 was generated.

LIST OF REFERENCE NUMBERS

1

Upper press plate

2

upper frame

3

press pad

4

press plate

5

pressure cylinder

6

unwinding

7

idler pulley

8th

Aerating film

9

idler pulley

10

rewinder

11

Lower press plate

12

press table

13

undercarriage

14

press pad

15

press plate

50

pneumatic equipment

100

Carrier plate / wood material board

101

Primer / primer layer

102

decorative layer

103

functional layer

104

return

Claims (13)

1. Method for refining a support board (100), in particular a wood or wood-based material board, on the surface of the top side of which a plurality of layers (101, 103) of a synthetic resin, preferably melamine resin, are applied and each layer is dried prior to the application of the next layer, wherein a coloured layer (102) for producing a decoration is provided between two layers (101, 103) and the dry layer structure is subsequently pressed between an upper and a lower press platen (1, 11) of a short-cycle press under the action of heat and pressure, whereupon the synthetic resin layers (101, 103, 104) melt, characterized in that a texturizing film (8) provided with depressions and/or elevations is arranged under the upper press platen (1), and the molten synthetic resin fluidly adapts itself to the depressions, and/or elevations, whereby, after the synthetic resin has hardened, a texture is formed, and in that the texturizing film (8) can be blown off the press platen (1) by means of an overpressure that is generated in pulses by a pneumatic device (50).
2. Method according to Claim 1, characterized in that a water-based point to which colour pigments have been added is used for the decorative layer.
3. Method according to Claim 1 or 2, characterized in that, prior to the pressing, at least one backing layer (104) is applied to the underside of the support board (100).
4. Method according to one or more of the preceding claims, characterized in that the top side is sanded prior to the application of the first layer (101) and liquid melamine resin is applied as the first layer (101) to the sanded top side.
5. Method according to Claim 4, characterized in that a primer layer is applied to the dried melamine resin layer (101).
6. Press apparatus for the pressing and texturization of support boards (100) provided with a plurality of resin layers (101, 103, 104), in particular wood or wood-based material boards, comprising an upper press platen (1) and a lower press platen (2), wherein a texturizing film (8) provided with depressions and/or elevations shall be arranged beneath the upper press platen (1), characterized in that the upper press platen (1) has a pressing plate (4) provided with a plurality of openings and the openings are connected to a pneumatic device (50), and in that an overpressure for blowing off the texturizing film (8) from the pressing plate (4) of the press platen (1) can be generated by the pneumatic device (50).
7. Press apparatus according to Claim 6, characterized in that the texturizing film (8) bears against the press platen (1).
8. Press apparatus according to Claim 6 or 7, characterized in that the texturizing film (8) can be fixed to the press platen (1).
9. Press apparatus according to Claim 8, characterized in that the texturizing film (8) can be sucked onto the press platen (1).
10. Press apparatus according to one or more_of Claims 6 to 9, characterized in that on one side next to the upper press platen (1) is arranged an unwinding apparatus (6) and on the opposite side of the press platen (1) is arranged a wind-up apparatus for the texturizing film (8).
11. Press apparatus according to Claim 9, characterized in that an underpressure for sucking the texturizing film (8) onto the pressing plate (4)/the press platen (1) can be generated by the pneumatic device (50).
12. Press apparatus according to Claim 6, characterized in that the overpressure can be generated in pulses.
13. Press apparatus according to Claim 6, characterized in that the openings in the pressing plate (4) can be fully covered by the texturizing film (8).

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