Multiple-layer edgebanding

Abstract

Composite of shaped bodies made from wooden materials with film-shaped substrates, wherein a surface of the shaped body has a first layer comprising a crosslinked radiation-curing hot-melt adhesive, said layer is covered with a second adhesive layer of a hot-melt adhesive, and said second adhesive layer is adhesively bonded to a film-shaped substrate. A method for producing composite shaped bodies of this type is provided, in which method, as one step, the surface is coated with a UV-crosslinkable hot-melt adhesive, and which method makes in-line production of the composite bodies possible.

Claims

1. A composite shaped element comprising wood materials and a film-shaped substrate, wherein a surface of the shaped element comprises a first layer of a crosslinked, radiation-cured melt adhesive, this layer being covered with a second adhesive layer of a hot melt adhesive, and this second adhesive layer being adhesively bonded to a film-shaped substrate.

2. The composite according to claim 1, wherein the radiation-curing adhesive is a UV-crosslinking adhesive containing 60 to 95 wt % polyester polymers and/or polyether polymers having at least one radiation-curing functional group, 5 to 40 wt % oligomers having at least two radiation-curing groups and/or monomers having one radiation-curable group, 0.1 to 20 wt % additives comprising photoinitiators.

3. The composite according to claim 2, wherein the UV-crosslinking adhesive further contains 10 to 50 wt % fillers or pigments, wherein the sum of all constituents is to yield 100 wt %.

4. The composite according to claim 1, wherein the first layer of the crosslinked radiation-curing melt adhesive is profiled and/or shaped.

5. The composite according to claim 1, wherein the second adhesive layer is made up of a crosslinked reactive polyurethane melt adhesive.

6. The composite according to claim 1, wherein the wood material is selected from wood, particle board, MDF panel, and/or the film-shaped substrate is selected from plastic film, paper substrate, veneer film, or plastic edge strip.

7. A method for manufacturing a composite according to claim 1, comprising the steps of: coating a surface of a shaped element with a radiation-curable melt adhesive; crosslinking the adhesive layer with actinic radiation; optionally, mechanically processing the crosslinked surface; applying a second melt adhesive onto the processed surface; adhesively bonding the first substrate to a film-shaped substrate.

8. The method according to claim 7, wherein the first melt adhesive is applied at a temperature at which the adhesive has a viscosity of between 1000 and 20,000 mPas.

9. The method according to claim 8, wherein the second melt adhesive can be applied to the crosslinked first layer immediately after crosslinking.

10. The method according to claim 8, wherein an NCO-reactive polyurethane melt adhesive is used as a second melt adhesive.

11. The method according to claim 7, wherein the layer thickness of the UV-crosslinkable adhesive is between 1 and 5 mm, and is crosslinkable by exposure to UV radiation.

12. The method according to claim 11, wherein the layer of the UV-crosslinkable adhesive is crosslinked by irradiated for between 0.3 and 15 seconds with UV radiation.

Description

ADHESIVE EXAMPLE 1

(1) A polyurethane was produced from:

(2) 25 g PPG 2000, 5 g saturated polyester diol with OH value=30 polyester (Dynacoll 7360), 20 g polyacrylate from methyl methacrylate/butyl acrylate copolymer, molecular weight approx. 60,000 g/mol (Degalan LP 65/12), together with 1.5 Irganox 1010 are dissolved hot (at 130 C.) while stirring.

(3) 5 g IPDI is then added, as well as 0.1 phosphoric acid and 0.5 DBTL, and reaction occurs at approx. 100 to 110 C.

(4) NCO value: approx. 1.2%.

(5) Viscosity: 30,000 mPas (at 110 C.).

(6) To this, 7 g OH-functionalized acrylate ester (Bisomer HEA) and 6 g of a difunctional acrylate oligomer (Ebecryl 3700) and 12 g tetrafunctional acrylate (Sartomer SR 444) are added.

(7) NCO value: 0.

(8) 30 g ground nepheline syenite is added, homogenized and degassed, and the volatile constituents are removed.

(9) Irgacure 819 (0.75 g), Additol HDMAP (0.75 g), and Stabilisator UV22 (0.2 g) are then mixed in.

(10) The resulting product had a viscosity of approx. 15,000 mPas (110 C.).

(11) It contained no isocyanate groups.

(12) The molecular weight (MN) was approx. 8000 g/mol.

(13) Shore D 70.

METHOD EXAMPLE 2

(14) A commercially usual particle-board panel is coated on the narrow side with a melt adhesive according to Example 1 at 110 C. The application pressure of the nozzle against the edge is approx. 20 bar, application quantity approx. 230 g/m.sup.2.

(15) A coating is produced that has penetrated approx. 3 mm into the pore structure and forms a continuous surface.

(16) Immediately thereafter the adhesive layer is irradiated with a UV lamp (0.9 sec, 200 W/cm) and crosslinked.

(17) The cured layer is processed immediately thereafter using a milling head.

(18) Onto this surface a reactive polyurethane adhesive (Purmelt RS 270/7) is applied (approx. 75 g/m.sup.2), and a thin PVC edge is bonded on immediately thereafter.

(19) The temperature resistance of the adhesive bond is more than 150 C.

(20) The pores of the substrate are no longer visible.

(21) The running smoothness of the surface is smoother and quieter than a corresponding comparison with no UV coating compound.

(22) The working steps can be carried out immediately after one another.