SK14012000A3 - Method for producing laminate coatings, and laminate coating - Google Patents

Abstract

The invention relates to a method for producing laminate coatings, in particular, for floor plates. The floor plates comprise a decorative paper that is impregnated with an amino resin and comprise an abrasionproof covering layer which is arranged thereon and which is provided with particle-shaped, fine aluminum oxide (corundum). According to the inventive method, the particle-shaped aluminum oxide is spread onto the wet impregnated decorative paper before drying the same. The decorative paper treated in such a manner is then pre-dried or pre-condensed. After drying, a covering layer comprised of fibrous material containing melamine resin is applied to the pretreated decorative paper. Finally, the entire assembly is completely dried.

Description

The invention relates to a process for the production of laminate coatings which are suitable and intended, in particular, for floorboards, which comprise a decorative resin impregnated paper and a wear-resistant coating with fine-grained alumina (corundum) placed thereon. Furthermore, the invention relates to such a laminate coating.

BACKGROUND OF THE INVENTION

It is known (DE 195 08 797 C1) to produce abrasion-resistant laminate coatings for floorboards such that a viscous mixture of melamine resin, cellulose fibers is applied in such an amount to the visible surface of the decorative paper after it has been soaked with resin and dried to residual moisture. corundum, additives and water, containing fine particulate abrasion-resistant mineral constituents, such that the coating has a thickness of 20 to 60 μπι after reaching the final moisture content, after which the decorative coating thus coated is dried to the final moisture content in at least one further working step.

In this known process, a viscous composition comprising a fine-grained alumina or corundum determining the abrasion resistance of the finished product is applied to the paper impregnated with melamine resin and dried. The fine-grained corundum particles are more or less evenly distributed in the coating formed from the viscous mixture and are thus also present on the surface of the coating.

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Furthermore, it is known to produce laminate coatings for floorboards by depositing an upper layer on the top or view side of a decorative paper impregnated with an amino resin or melamine resin, which has fine-grained alumina or corundum particles on the top of the paper-containing substrate.

These two known processes require two separate steps, namely, on the one hand, the production of a separate mixture containing the corundum particles and its application, on the other hand, the production of the top layer, which must then be separately deposited. Therefore, these known methods are relatively costly and thus less economical.

A further substantially more significant disadvantage is that the press plates or press strips used to machine laminate coatings are damaged by abrasion from the corundum particles present on the surface of the laminate, resulting in relatively fast graying of the surfaces of the finished laminate coatings. Accordingly, using known production technologies, the press thrust plates used or the press strips consisting of sheet metal have to be repaired or reground quite often in order to compensate for the blunting of their surface. Accordingly, the service life of the press thickeners or the press strips is relatively short.

Repairing the surfaces of the press plates or the press strips not only entails high processing costs, but also the downtimes of the presses equipped with them, which negatively affects the economy in the abrasion-resistant production of laminate coatings.

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SUMMARY OF THE INVENTION

The invention is based on the task of making the production of wear-resistant laminate coatings more economical than hitherto.

This object is achieved according to the invention in a manner having the features of claim 1.

Advantageous embodiments of the invention are the subject of further claims.

According to the present invention, it is possible in a single process to produce a laminate coating for floorboards or the like, wherein the fine alumina or corundum particles imparting an abrasion-resistant laminate coating are encapsulated on the surface of the coating such that they cannot damage the press plates or bands of machines or presses used for the production of laminate coatings.

The melamine resin cover layer containing the fibrous material applied to the impregnated decorative paper after spreading the particulate alumina is translucent, so that the decoration of the decorative paper is clearly visible. Due to the covering of the particles imparting abrasion resistance to the finished product during the production of the laminate coating, it is not necessary to expect graying and thus a deterioration of the surface of the produced laminate coating even after prolonged use of the press plates or press strips.

In other words, the surface of the laminate coating produced according to the invention remains clear because the fibers or also the fibers applied as a sheath The corundum particles do not change or affect the visibility of the decorative paper decor, but on the other hand, the press plates or the press strips of the presses or other machines used for the production of laminate coatings protect against premature wear.

The laminate coatings according to the invention can be applied, for example, to chipboard or fiber boards which have previously been provided with an anti-deformation underlay on the upper side and / or the lower side.

DETAILED DESCRIPTION OF THE INVENTION

The invention is further illustrated by two exemplary embodiments.

Example 1

The decorative paper with a basis weight of 70 g / m ² is first impregnated in the bath with melamine resin, the weight after drying being 140 g / m ² . 20 g / m ^{2 of} corundum is spread on the still wet paper strip.

The paper is then pre-dried at 180 ° C to a moisture content of 15%.

A fiber web of 80 g / m @ ² , consisting of 80% melamine resin and 20% cellulose fibers with a length of 60 μιη, is then applied to the paper web. This is followed by a final drying at 180 ° C to a humidity of 6.0 to 6.5%.

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The impregnated semi-finished product thus produced is pressed onto a backing HDF board in a short-cycle press at a temperature of 205 C, a relative pressure of 2.5 MPa and a pressing time of 20 s.

The laminate flooring thus obtained complies with EN 438 and an abrasion value of IP 10 000.

Example 2

The decorative paper having a basis weight of 80 g / m ² is impregnated with a melamine resin, the basis weight after subsequent drying being 150 g / m ² . A fine-grained alumina is spread on a still wet paper web in an amount of 8 g / m ² . The paper web is then dried at 210 ° C to a moisture content of 12%. Subsequently, a 40 g / m ² fleece consisting of 85% melamine resin and 15% glass fibers with a length of 3 mm and a diameter of 10 μιη is applied. The procedure follows Example 1.

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Claims (6)

A process for the production of laminate coatings, in particular for floorboards, comprising a decorative paper impregnated with an amino resin and an abrasion-resistant coating with fine-grained alumina (corundum) disposed thereon, characterized in that the particulate alumina is spread after the pre-drying, a covering layer of melamine resin-containing fibrous material is applied to the pre-treated decorative paper, and the whole is finally dried. Method according to claim 1, characterized in that a fibrous web containing a melamine resin is deposited on the decorative paper as a covering layer. Method according to claim 1 or 2, characterized in that alumina or corundum with a particle size of about 125 μιη is spread on the decorative paper. Method according to any one of claims 1 to 3, characterized in that the basis weight of the coated decorative paper after drying is about 140 to 150 g / m ² . A process according to any one of claims 1 to 4, wherein the alumina is spread in an amount of about 20 g / m ² . The process according to any one of claims 1 to 4, wherein the alumina is spread in an amount of about 8 g / m ² .