NL9400274A - Plate-shaped material. - Google Patents

Description

Title: Plate-shaped material

The present invention relates to a plate-shaped material based on a substrate coated with at least one layer of a thermoplastic plastic.

Generally, the production of plate materials based on more than one layer poses the problem of ensuring good adhesion between the various layers. This problem occurs, for example, in the manufacture of sandwich plates, but also in the application of protective and / or decorative surfaces to plate materials, whether or not composed, of composite materials.

U.S. Patent 5,037,690 discloses a sandwich material composed of a core layer with a layer of fiber material impregnated with a polyurethane resin applied to both surfaces thereof. Especially in case the core material has a honeycomb structure, in this way a good adhesion between the fiber layer and the honeycomb structure can be obtained since the honeycomb material is slightly pressed into the fiber layer where the polyurethane resin ensures adhesion between fiber and core. The polyurethane resin also has the function of binder for the surface layer.

Although this provides a simple structure for a sandwich material, there is still a need for a more universal method for obtaining adhesion of, inter alia, surface layers to substrates. This need exists both for applying decorative layers and / or protective layers on mainly single materials, as well as for sandwich structures.

In the case of single materials, one can think, for example, of applying protective and / or decorative layers to plates that are used for counter tops, table tops and the like.

When finishing such materials, a plastic layer is often applied to the surface. It is preferred to use acrylic polymers or olefin polymers, because they are chemically inert and usually have a mechanically strong surface (scratch-resistant). On the other hand, this inertia has the problem that the adhesion of the plastic to the base material, the substrate, is difficult.

Many types of adhesives have already been tested, but no satisfactory solution has yet been found to obtain good adhesion.

Another group of materials where it is very important that there is good adhesion is formed by the sandwich materials. These materials consist of a mostly lightweight core material, for example a honeycomb material, which is provided with two top layers. In many cases it is desirable to build up the top layers from a number of layers, in which the problem of adhesion often plays a role. If one or more materials are to be processed which are difficult to glue, the result may be that the strength of the entire plate is too low. This can occur, inter alia, if one wishes to incorporate a polyolefin or polymethacrylate in the plate.

The invention now provides a solution to the problem of obtaining sufficient adhesion between various materials. The invention therefore relates to a plate-shaped material comprising a substrate which is coated with at least one layer of a thermoplastic plastic, wherein said layer on the substrate side is provided with fibers which are anchored in the plastic layer and partly protrude there, and wherein said plastic is used with the aid of an adhesive is adhered to the substrate.

In practice this means that the layer of plastic material to be applied is treated in such a way that a fiber layer is anchored in its surface.

This can be done, for example, by means of a (direct or indirect) heating of the surface layer, after which a fiber layer is partially pressed into the surface. Examples of heating methods are radiant heat, open flame heating, induction heating, electromagnetic radiation and heating using a hot plate or a hot liquid. It is also possible to soften the surface with a suitable solvent or to use a combination of both methods. The thermoplastic plastic thus obtained, the surface of which is provided with fibers, is then applied to the surface of the substrate by means of an adhesive.

According to the invention, a single or composite material is generally used as the substrate.

This material may be selected from the group consisting of thermoplastic plastic sheet material, wood, plywood, chipboard, filler sheet material (puffed corn, polystyrene granules, microspheres, glass spheres or fibers, earth, clay, foamed rock and the like) which are bonded with organic and / or inorganic binders (thermosetting plastics, biological binders, cement, water glass, gypsum and the like), multilayer systems based on core material and / or sheet material and filled or unfilled honeycomb material. In case a honeycomb material is used, this material will be provided with two top layers, on which the fiber-provided plastic is applied. It is also possible to use all kinds of combinations of this type of materials.

Said products mainly fall into two groups, namely the single materials suitable for the manufacture of worktops and other plate-shaped objects, and the composite materials or sandwich materials, consisting of a light core and two surface layers.

The coating of a thermoplastic plastic on the substrate can be applied in a number of ways. This can be done, for example, using hot-melt adhesives, or with a thermosetting plastic (resin with hardener). Examples of thermosetting plastics are epoxy resins and unsaturated polyester resins.

However, in the case when a plastic material is used as a substrate, it is also possible to anchor the fibers in the substrate in the same manner as in the coating layer, for instance by applying the fibers of the coating layer in a softened surface of the substrate. This softening can be accomplished by heating the surface of the substrate or softening with a solvent. It is also possible to apply the coating immediately after the production of the substrate, if it is still in a soft state, of course, in such systems, the method can also be reversed, that is to say, the fiber layer is applied in the surface of the substrate. then the coating is adhered to the surface of the fibers using appropriate techniques such as the use of glue or softening.

According to the invention, all kinds of materials can be used as fibers, each of which can in turn be incorporated in all kinds of structures in the thermoplastic plastic. Synthetic and / or natural fibers can be used as materials for the fibers. It is preferred to use fibers selected from the group consisting of hemp, flax, elephant grass, jute, ampas, glass fibers, carbon fibers and plastic fibers such as polyester fibers, acrylic fibers, polyethylene fibers, polypropylene fibers and polyamide fibers. These fibers can be applied as loose fibers in the thermoplastic plastic material, or as non-woven, knitting, felt, a woven material or a scrim.

The plate materials according to the invention can, as stated, consist of single materials, which are provided with a coating layer or of composite materials, there are hardly any restrictions with regard to the construction and structure of these materials.

An important application of the invention lies in the manufacture of worktops, such as countertops or table tops, which worktops must be provided with a plastic finishing layer. The application of such a layer is not easy, since the materials most suitable for use as a finishing layer, such as acrylate polymers and more particularly polymethyl methacrylate, exhibit poor adhesion to the usual substrate materials. The invention now provides a simple system for these worktops, whereby it has also become possible to obtain a good adhesion of acrylates to the usual base materials, such as wood, plywood, chipboard, MDF and the like. It is noted that two problems play a role in the manufacture of such worktops. First, the top layer should be well adhered to the substrate. This can sometimes be realized during the manufacture of the blade. A second aspect is the finishing strip that is later applied to the side of the material. This frame must adhere well and be watertight to the material. Especially for the use of PMMA in this application, no good solution has been found to date. According to the invention it is now possible to apply PMMA properly using an anchored fiber layer with a thermosetting plastic or a hot-melt glue.

Another important field of application of the invention lies in the composite materials, or sandwich structures. Due to the nature of the invention, it is now possible to provide various types of sandwich materials, which have all kinds of suitable properties. Since it is now possible to apply relatively inert materials as a coating to other materials, lightweight construction materials can be provided in a relatively inexpensive manner for all kinds of applications according to the invention. Examples thereof include plate materials for grease traps, sewage components, and (insulating) sandwich plates, for example for wall or roof panels, by processing bubble wrap that can be provided with an aluminum layer if desired, in combination with honeycomb materials in the core, on which a finishing layer is applied. is. Such wall and roof panels can be provided on the outside with a masonry structure or a roof tile structure. It is also possible to provide heating elements in the material, for example in the form of heating strips of conductive plastic (provided with a fiber layer), or to use decoration materials in or under the top layer.

Within the framework of the invention, use can also be made of structures based on paper impregnated with plastic or provided with a plastic layer, anchoring in the plastic fibers.

Other applications of the sandwich panels according to the invention are silos for solids or liquids, housings for air ventilation / air conditioning systems, gas scrubbers and cooling towers, and the like. In general, these materials can be used where a load bearing capacity must be combined with low weight and possibly chemical resistance.

In this connection it is noted that in the manufacture of such composite materials it is also possible to use plastic layers which are provided with fibers on both sides, so that it is possible to 'build on' as it were.

Both the worktops and the sandwich materials according to the invention can provide a decorative layer. A possible embodiment of such decoration layers is formed by resin-bonded solids with a decorative effect. Examples include natural stone, glitter-effect waste materials (anthracite grit and the like), natural materials such as corn, peas, rice and other seeds.

Such a transparent resin-based decoration layer can, if desired, be provided with glass particles, which are preferably applied in the top layer of the resin, so that a strong, scratch-resistant and decorative sheet is obtained. Preferably, the resin and the glass particles are chosen so that the refractive indices are equal, which from a decorative point of view offers before. It is noted that such a decoration layer can also be applied without the use of the fiber-based adhesive layer.

A suitable material which can be used according to the invention as a core material for a sandwich plate comprises a filled or unfilled honeycomb material and two cover layers, which are built up from a layer of a plastic material, adhered to a nonwoven fabric, containing expanded microspheres, the cover layers are bonded to the honeycomb material via the fiber web using a thermosetting plastic. A finishing layer can again be applied to such a core material, this core material functioning as a substrate for the finishing layer.

Other embodiments and applications of the invention are described with reference to the figures and further elaborated in the examples. It should be noted that the invention is not limited to what is shown in these figures and examples.

Figure 1 shows a conventional sandwich panel, which is constructed from a core material (honeycomb) combined with two layers of thermosetting material.

Figure 2 shows a themoplastic sheet in which a fiber mat is anchored.

Figure 3 shows a comparable plate in which a glass fabric is anchored.

Figure 4 shows a plate as in figure 2, measuring a fiber mat on both sides.

Figure 5 shows a sandwich material based on a conventional sandwich material on which two plates according to Figure 2 have been applied using a thermosetting resin.

Figure 6 shows a multi-layer construction composed of a plate according to Figure 4 and two plates according to Figure 2, which are bonded together with layers of thermosetting resin. Figure 7 shows an insulating sandwich construction consisting of a honeycomb core material and two layers of plastic bubble wrap, which are applied with the studs to the honeycomb and which are provided with an aluminum layer on the outside. Using the invention, a coating layer of a thermoplastic plastic, such as polyolefin or polyester, is applied to the aluminum layer.

Figure 8 shows the principle of applying a finishing strip to the side of a worktop.

Claims (12)

Plate-shaped material comprising a substrate which is coated with at least one layer of a, preferably thermoplastic, plastic, wherein said layer on the substrate side is provided with fibers which are anchored in the plastic layer and partly protrude from it, and said plastic is adhered to the substrate using an adhesive Plate-shaped material according to claim 1, wherein the substrate is made of a single material or of a composite material. The sheet material according to claim 1 or 2, wherein the substrate is selected from the group consisting of sheet material of thermoplastic plastic, wood, plywood, chipboard, MDF, sheet material of fillers bonded with organic and / or inorganic binders, multilayer systems based on base of core material and / or sheet material and filled or unfilled honeycomb material provided with two top layers. Plate-shaped material according to claims 1-3, comprising two layers of a thermoplastic plastic, said layers on the substrate side being provided with fibers which are anchored in the plastic layer and partly protrude there and are bonded to a core material by means of an adhesive Plate-shaped material according to claims 1-4, wherein the adhesive used is a thermosetting plastic or a hot-melt adhesive. A plate-shaped material according to claims 1-5, wherein the fibers are anchored in the material of the top layer using heat and pressure. A plate-shaped material according to claims 1-6, wherein said fibers are used in the form of a non-woven, a knit, a woven material or a scrim. A sheet material according to claims 1-7, wherein said fibers are selected from the group consisting of natural or synthetic fibers, such as hemp, flax, jute, elephant grass, glass fibers, carbon fibers and plastic fibers such as polyester fibers, acrylic fibers, polyethylene fibers, polypropylene fibers and polyamide fibers. Method for manufacturing a sandwich material comprising a core layer and one or more top layers of thermoplastic plastic, which top layer is provided on one surface with a fiber layer which is anchored partly and protrudes in the thermoplastic plastic, said fiber layers having is bonded to the core material using an adhesive. A method according to claim 9, characterized in that said fiber layer is impregnated with a thermosetting plastic and optionally a hardener therefor, joining the top layer provided with an impregnated fiber layer with the core material, followed by curing the thermosetting plastic. Sheet material suitable for use as a core material in the manufacture of the sandwich material according to claim 9 or 10, comprising a filled or unfilled honeycomb material and two cover layers, which are built up from a layer of a plastic bonded to a nonwoven fabric. contains expanded microspheres, the coatings adhered to the honeycomb material via the nonwoven fabric using a thermosetting plastic. 12. Work top comprising a plate-shaped base material, provided with a finish on the basis of an acrylic plastic, preferably polymethyl methacrylate, the finish being applied by providing the plastic with fibers anchored in that surface of the plastic to be adhered to the base material, while part of said fibers protrudes from the surface and which plastic is adhered to the base material with an adhesive.