Process for producing panels with footfall and ambient sound deadening

Abstract

A panel has an upper side facing the room in the use position and a lower side facing the floor. The lower side is coated, at least in sections, with a bonding layer composed of polymer. The bonding layer has an uneven surface on the outer side facing away from the panel, and has been coated at least in sections with a damping layer composed of polymer. A covering composed of panels, a process and an apparatus for producing the panels are also described.

Claims

1. A process for producing panels which have sound deadening, comprising the steps of: applying a bonding layer to a lower side of a panel; shaping an outer side of the bonding layer, facing away from the panel, to an uneven surface comprising projections by virtue of a profiled tool in a press at temperatures between 100 C. and 190 C., said bonding layer having a density of more than 600 kg/m.sup.3; and applying a damping layer which is composed of polymer to the outer side of the bonding layer at least in sections such that the damping layer facing towards the lower side of the panel adopts the mirror image of the uneven surface and that the projections are embedded in the damping layer.

2. The process according to claim 1, comprising composing the bonding layer from polymer which is applied to the lower side of the panel before the outer side is shaped.

3. The process according to claim 1, comprising applying the bonding layer and the damping layer by means of at least one of rolling, knife-coating, casting, spreading and spraying.

4. The process according to claim 1, comprising applying at least one of the polymers of the bonding layer and of the damping layer in the liquid state.

5. The process according to claim 1, further comprising applying at least one of the bonding layer and the damping layer at temperatures up to 190 C.

6. The process of claim 5, wherein said applying step comprises applying at least one of the bonding layer and damping layer at temperatures up to 150 C.

7. The process of claim 5, wherein said applying step comprises applying at least one of the bonding layer and damping layer at temperatures up to 100 C.

8. The process according to claim 1, further comprising cooling at least one of the bonding layer and the damping layer after application.

9. The process according to claim 1, further comprising shaping the outer side of the bonding layer to an uneven surface with using one of a profiled mould, a profiled roller and a profiled press platen.

10. The process according to claim 1, further comprising smoothing the damping layer after the application.

11. A process for producing panels which have sound deadening, comprising the steps of: at the manufacture stage, applying a bonding layer to a lower side of a panel and shaping an outer side of the bonding layer, facing away from the panel, with a profiled tool in a press at a temperature between 100 C. and 190 C., said bonding layer having a density of more than 600 kg/m.sup.3, to produce an uneven surface comprising projections; and in a use position, applying a damping layer which is composed of polymer at least in sections to the outer side of the bonding layer such that the damping layer facing towards the lower side of the panel adopts the mirror image of the uneven surface, and that the projections are embedded in the damping layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Details of the invention are explained in detail using the example of one embodiment of the invention. The figures show:

(2) FIG. 1 a cross section through a schematic illustration of a panel provided with an inventive sound deadening system;

(3) FIG. 2 a cross section through a schematic illustration of a panel provided with a bonding layer exposed to sound;

(4) FIG. 3 a cross section through a schematic illustration of a panel provided with a bonding layer and a damping layer exposed to sound;

(5) FIG. 4 a cross section through a schematic illustration of a second embodiment of a panel;

(6) FIG. 5 a cross section through a schematic illustration of a third embodiment of a panel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

(7) FIG. 1 shows a panel 2 with a core 3 composed of HDF whose upper side 4 is sealed with a resin-impregnated decorative paper 6 and an overlay 8. This forms a durable wear-resistant panel 2 which can be used, for example, as a floor covering. A backing 12 of paper which ensures the dimensional stability of the panel 2 is pressed onto the lower side 10 of the panel 2. The backing 12 counteracts the pulling forces which act on the panel 2 in the course of application of decorative paper and overlay 8.

(8) A bonding layer 14 composed of hard EVA is applied to the lower side 10 of the panel 2, more specifically to the backing 12, by means of a profiled roller. The bonding layer 14 is uneven. It has projections 17 which are arranged alongside one another at a distance of 0.6 mm to 1.2 mm. The maximum thickness of the bonding layer 14 is 3 mm; the profile depth, i.e. the distance between the thickest application and the thinnest application of the bonding layer, is 1.2 mm.

(9) The outer side 13 of the bonding layer 14 is covered by a damping layer 16 composed of polyolefins. The damping layer 16 is applied by means of a roller with a chromium-plated surface which brings about smoothing of the outer side of the damping layer 16.

(10) In the use position, the panel 2 rests on a floor. When the panel is walked on, the panel 2 is stressed mechanically and set in vibration. FIGS. 2 and 3 show this state. The vibration radiates firstly back into the room laid with the panel 2. The vibration secondly radiates onto the floor on which the panel 2 lies and is transmitted from there to rooms adjoining it.

(11) FIG. 2 shows a schematic section from the panel 2, specifically its bonding layer 14 of hard EVA applied on the lower side 10. The projections 17 of the bonding layer 14, which are rigid owing to the material properties of the hard EVA, are set in vibration together with the panel 2 when walked on. The direction of force is indicated by the arrow A. However, they vibrate approximately at right angles based on the plane of the panel 2; see arrow B.

(12) FIG. 3 shows the projections 17 of the bonding layer 14 embedded into the damping layer 16. The projections 17 are composed of hard EVA and vibrate or attempt to vibrate in the damping layer 16. As a result of this motion, the vibration of the panel 2 is effectively dissipated. The motion of the projections 17 is converted in the damping layer 16 composed of soft EVA first to friction and then to heat. The vibration of the projections 17 is additionally effectively damped by the damping bodies 18 present in the damping layer 16. The damping bodies 18 are spherical hollow bodies which have likewise been produced from elastic polymer. This conversion of the vibration energy introduced into the panel 2 by virtue of it being walked on to friction or heat energy brings about an effective improvement both in the footfall deadening and in the ambient sound deadening. As a result of the flat outer side 19 of the damping layer, good contact of the panel 2 on the substrate is ensured.

(13) FIG. 4 shows a second embodiment of the inventive panel 2. The panel 2 has a core 3 composed of chipboard. The chipboard does not have any further coating; it is intended to serve as a comparative panel and substrate for a floor covering. For improved sound deadening, both with regard to footfall and with regard to ambient sound, a deadening mat 20 is adhesive-bonded to the lower side 10. The adhesive layer 22 is indicated in FIG. 4.

(14) The deadening mat 20 is a sound-reducing coating. It can be adhesive-bonded at the manufacture or installation stage. It consists of the bonding layer 14 composed of hard polymer of low plastic deformability (hard EVA) with the projections 17 which project into the deadening layer 16. The deadening layer consists of soft, readily plastically deformable polymer (soft EVA). The bonding layer 14 is adhesive-bonded to the deadening layer 16.

(15) The deadening mat 20 is adhesive-bonded to the lower side 10 of the panel 2 such that the bonding layer adjoins the lower side 10 of the panel. The adhesive layer 22 can be applied actually to the bonding layer 14 such that the two components adhere to one another when sound-reducing coating 20 and the panel 2 are joined. This embodiment of the inventive panel 2 with the separately designed deadening mat 20 shows the particularly flexible and simple handling of the deadening system.

(16) FIG. 5 shows a panel 2 whose core 3 consists of HDF and which otherwise has the same surface coatings and an identical backing to the panel shown in FIG. 1. At the manufacture stage, the bonding layer 14 with the projections 17 is applied. The damping layer 16, a 0.8 mm-thick soft EVA layer, is applied to a film 24 composed of polyethylene. In the use position, the panel 2 is laid onto the spread-out damping layer 16 such that the projections 17 sink into the damping layer 16 and plastically deform it as they do so.