HK1181712A - Laminated decorative plate and method for the production thereof - Google Patents

Description

Laminated decorative board and its manufacturing method

The divisional application is based on the original Chinese patent application with the application number of 200880021587.7, the application date of 2008, 6, 4 and the title of 'laminated decorative board and manufacturing method thereof'.

The present invention relates to a laminated decorative panel and a method for manufacturing the same according to the general concept of claim 1.

Such decorative panels are known, for example, from WO 03/095202a 1. It consists of a plate-shaped core of fibrous material, an intermediate layer containing resin on one side, a decorative layer and a cover layer provided with projections (Relief), with a counter-acting layer (Gegenzugschicht) on the other side. The decorative layer represents a graphic image of the surface of the simulated (limitierten) material. In this process, the projection of the cover layer must be arranged exactly on top of the pattern of the decorative layer. This is achieved by placing a decorative layer, which is usually composed of printed paper, on the intermediate layer, preferably without adhesive impregnation, whereby a change in the dimensions of the male die (Reliefstempel) for the cover layer is avoided.

The intermediate resin-containing layer is formed here before hot pressing in the form of a solid coating on the core or in the form of a separate, previously prepared adhesive layer. The binder content of this layer must be determined according to the absorption of the adjacent layers during hot pressing. It is also necessary to cut the printed decorative paper before hot pressing and to place it in a precisely fitting manner on the prepared core.

The object of the invention is to provide a laminated decorative panel which is simpler and less expensive to produce, and to provide a method for its production.

This object is achieved by a trim panel according to claim 1 and a method according to the dependent claim 8.

It has been found that if a liquid, pressure and/or heat curable glue is used, it is no longer necessary to separately manufacture the resin-containing intermediate layer. Such glue may be applied in the same process step in which the decorative layer and optionally the cover layer are mounted. The cutting of the decorative layer is superfluous since the matching accuracy can be ensured with the usual printing techniques. This results in a significant simplification and cost reduction of the production method.

The absorption of the core and the decorative layer can now be taken into account directly during the manufacturing process via the application of glue. The storage properties of the specially coated core material or intermediate layer material are not necessary.

The liquid, pressure and/or heat curable glue is preferably a urea-formaldehyde glue. Such glues are generally supplied as two-component systems and are mixed shortly before application. They can be cured by heating. The particular product is sufficiently cured under pressure, even at ambient temperature, to secure the decorative layer. A suitable product is for example an adhesive 1206 with a curing agent 2547 from Casco Adhesives, stockholm, sweden.

Also preferred is a melamine formaldehyde glue. Such a glue is advantageous and serves to simplify the production process if the same product as the cover layer is used for this purpose. Melamine urea-formaldehyde glue may also be used.

In a preferred embodiment, the cover layer is formed in a cellulose-free manner. It does not comprise in particular a cellulose-containing carrier layer such as paper or the like. Preferred materials for the cover layer are melamine resins or acrylic lacquers (acryl lacquer). PVC may also be used. Fine powders of hard solids may be introduced into these coating materials, thereby improving wear resistance. Suitable for this purpose are, for example, corundum.

An advantage of a cellulose-free cover layer is a higher transparency. Furthermore, they can be produced more simply and more cost-effectively, since no fibrous support material is required and their separate impregnation is omitted.

The cover layer can be applied to the decorative layer as a film made of a thermoplastic material or as a liquid.

Printed paper is particularly preferred as the decorative layer. The printed side can be covered with a thin lacquer film which, however, does not impregnate the paper layer and does not change its dimensions.

Suitable as core materials are fibrous materials such as High Density Fiberboard (HDF) or Medium Density Fiberboard (MDF) or also chipboard. HDF is particularly preferred.

If the decorative layer and the cover layer are present only on one side of the core, it is expedient to mount a so-called counter-acting layer on the other side, in order to prevent the finished board from being deformed or bent due to the influence of temperature or humidity. The thickness of this layer is adjusted according to the coating on the other side. Suitable for the layer are, for example, neutral papers with solid or liquid resins as glue.

The invention also comprises a method for manufacturing a laminated decorative panel according to the invention as described above according to the juxtaposed claim 8. The method is simpler than the prior art, since it can be carried out in one or two steps. That is, the liquid state, the application of a pressure and/or heat curable glue, the placement and pressing of the decorative layer and optionally the mounting of the counter-acting layer can also be carried out in one process step as a laminating method, and then in a second process step the cover layer is applied as a liquid layer or film and the entire layer structure is then cured under the action of pressure and heat, wherein the raised structure is simultaneously shaped in the surface of the cover layer by means of a suitably configured pressing tool. In the first step, the operation can be carried out without heat. The second process step may follow the first process step and thus may be run continuously. In the first process step, for example, a calender (kalandersress) can be used, which is equipped with suitable introduction devices for the core material and the decorative layer and optionally the counter-acting material and application devices for the liquid glue. The sheet may optionally be separated after calendering and cured under pressure and heat in a short cycle press (kurztaktpress). The second process step can also be carried out continuously in a heated double belt press, wherein the plates can then be separated as desired.

The pressing tool (e.g. a plate or a roller) for the surface relief forming can be arranged on a pattern of the decorative layer, for example a registration mark (passmark n) on the decorative layer, which is read by means of an electro-optical system. Thereby improving the simulation of surface pores with materials, such as wood, associated with visible patterns. It is also possible to work continuously, since the decorative layer no longer needs to be cut and optionally placed onto the core manually.

Of course, the product can also be stored, optionally intermediately, after the first process step (zwischengelager).

It is also possible to manufacture decorative panels according to the invention with a particularly deep surface structure if the intermediate layer is still flexible during the pressing-in process and/or the thickness of the cover layer is appropriately selected.

The product and the method according to the invention also do not require a particularly expensive printing base paper (druckbasispiier) for the decorative layer in order to achieve a good alignment of the graphic motif with the surface relief.

Two examples of laminated decorative panels according to the invention and methods for their manufacture are given below.

A) Layer construction of a decorative panel with urea-formaldehyde glue (from top to bottom):

1) a covering layer of melamine resin or a previously impregnated covering film applied in liquid form. In both cases corundum is embedded in the cover layer, which acts as a friction-inhibiting effect.

2) Printed decorative papers that are dry (i.e. not impregnated) or are coated as a coating film (finishfoil) with a thin paint film.

3) With a layer of urea-formaldehyde glue.

4) HDF board

5) With a layer of urea-formaldehyde glue.

6) A reverse paper (optionally required) for covering the underlying glue layer.

In the process for manufacturing such a panel, the layers 2) to 6) are firmly adhered to each other in the lamination process. The layer 1 is subsequently pressed into the decorative paper in a short cycle press (kurztakpress) or in a continuously operating double belt press, wherein a part of the wear-resistant melamine layer closes the surface. The raised structures are also simultaneously pressed in during this process.

B) Layer construction of a decorative panel with liquid melamine as a tie resin glue layer (from top to bottom):

1) a covering layer of melamine resin applied in liquid form. Corundum, which has a friction-inhibiting effect, is embedded in the covering layer.

2) Printed decorative paper: this decor paper is dry, however the melamine resin can penetrate into the paper from the bottom up during pressing.

3) A layer of melamine applied in liquid form.

4) HDF board

6) The reverse-acting layer as described at points 5 and 6 in a).

In the method for producing such a panel, the dried decorative paper can be pressed onto a carrier sheet (for example an HDF sheet) in only one operation in the following manner: the above-mentioned layers 2 to 5 are pressed or placed cold between 2 calendering rolls in a first partial step and subsequently pressed against one another under the action of heat and pressure in a short-cycle press or in a continuously operating double belt press. The "dipping" step is no longer necessary in this process.

Claims (5)

1. A laminated decorative board has a core made of a fibrous material or a cut material, a resin-containing intermediate layer on at least one side of the core, a decorative layer not impregnated with resin having a graphic image of the surface of the material to be simulated.

2. The trim panel of claim 1 wherein said core is comprised of a high density fiber material (HDF).

3. Decorative board according to claim 1 or 2, characterized in that the decorative board has a counter-acting layer on the opposite side of the decorative layer.

4. The trim panel of claim 3 wherein said reverse acting layer is comprised of a resin containing intermediate layer and paper that is not impregnated with resin.

5. Decorative board according to claim 1 or 2, characterized in that the decorative layer is printed paper.