MULTI-LAYERED STRUCTURE FOR THE REALIZATION OF A FLOOR COVERING WITH SOUND-INSULATING PROPERTIES

Abstract

The invention relates to a multilayer structure (1) for producing a floor or wall covering, the structure comprising at least one backing layer (2) made of crosslinked polyolefin foam, giving the structure sound-insulating properties, the backing layer (2) having a lower face intended to be bonded to the floor or wall, and an upper face bonded to an upper layer (3) produced from a plastic material, linoleum or rubber.

According to the invention, at least one of the faces of the backing layer (2) has a surface tension of greater than or equal to 40 mN/m.

Claims

1. A multilayer structure (1) for producing a floor or wall covering, the structure comprising at least one backing layer (2) made of crosslinked polyolefin foam, giving the structure sound-insulating properties, the backing layer (2) having a lower face intended to be bonded to the floor or wall, and an upper face bonded to an upper layer (3) produced from a plastic material, linoleum or rubber, characterized in that at least one of the faces of the backing layer (2) has a surface tension of greater than or equal to 40 mN/m.

2. The structure according to claim 1, characterized in that the lower face of the backing layer (2) has a surface tension of greater than or equal to 40 mN/m.

3. The structure according to claim 1, characterized in that the upper face of the backing layer (2) has a surface tension of greater than or equal to 40 mN/m.

4. The structure according to claim 1, characterized in that the upper face and/or the lower face have undergone a surface treatment by fluorination.

5. The structure according to claim 1, characterized in that the backing layer (2) has a thickness of between 0.5 and 2 mm, and preferably equal to 1 mm.

6. The structure according to claim 1, characterized in that the backing layer (2) has a density of between 70 and 120 kg/m.sup.3, and preferably equal to 95 kg/m.sup.3.

7. The structure according to claim 1, characterized in that the upper layer (3) is produced from polyvinyl chloride.

8. The structure according to claim 1, characterized in that it comprises a wear layer (4), transparent to visible light and linked to a decorative film (6).

9. The structure according to claim 7, characterized in that it comprises an intermediate layer (5) produced from polyvinyl chloride, bonded to the backing layer (2).

10. The structure according to claim 9, characterized in that the intermediate layer (5) produced from polyvinyl chloride is plasticized and comprises mineral fillers.

11. A method for manufacturing a multilayer structure (1) for producing a floor or wall covering, the multilayer structure (1) comprising a backing layer (2) made of crosslinked polyolefin foam, giving the structure sound-insulating properties, the backing layer (2) having a lower face intended to be bonded to the floor or wall, and an upper face bonded to an upper layer (3) produced from polyvinyl chloride, characterized in that, before bonding of the upper face of the backing layer (2) to the upper layer (3), said upper face undergoes a surface treatment that increases its surface tension to a level greater than or equal to 40 mN/m.

12. The method according to claim 11, characterized in that the lower face of the backing layer (2) also undergoes a surface treatment that increases its surface tension to a level greater than or equal to 40 mN/m.

13. The method according to claim 11, characterized in that the surface treatment consists of a surface treatment by fluorination.

14. The method according to claim 11, characterized in that the surface treatment consists of a corona treatment.

15. The structure according to claim 2, characterized in that the upper face of the backing layer (2) has a surface tension of greater than or equal to 40 mN/m.

16. The structure according to claim 2, characterized in that the upper face and/or the lower face have undergone a surface treatment by fluorination.

17. The structure according to claim 3, characterized in that the upper face and/or the lower face have undergone a surface treatment by fluorination.

18. The structure according to claim 8, characterized in that it comprises an intermediate layer (5) produced from polyvinyl chloride, bonded to the backing layer (2).

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0042] Other features and advantages will be clearer from the following description, provided as a non-limiting example, in reference to the appended figures, in which:

[0043] FIG. 1 is a schematic sectional depiction of a first embodiment of a multilayer structure according to the invention;

[0044] FIG. 2 is a schematic depiction similar to that of FIG. 1, illustrating a second embodiment of the invention;

[0045] FIG. 3 is a schematic depiction similar to that of FIG. 1, illustrating a third embodiment of the invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

[0046] With reference to FIGS. 1 to 3, the invention relates to a multilayer structure (1) for producing a floor or wall covering having sound-insulating properties.

[0047] To this end, and in a known manner, the multilayer structure (1) comprises at least one backing layer (2) made of crosslinked polyolefin foam, giving the structure sound-insulating properties, which structure comprises a lower face intended to be bonded to the floor or to the wall.

[0048] The backing layer (2) made of crosslinked polyolefin foam, for example in particular made of crosslinked polyethylene foam, preferably has a thickness of between 0.5 and 2 mm, for example 1 mm, and a density of between 70 kg/m.sup.3 and 120 or even between 80 and 120 kg/m.sup.3, for example equal to 95 kg/m.sup.3.

[0049] From the foregoing, the backing layer (2), associated with an upper layer (3) comprising a wear layer (4) produced from a plastic material, linoleum or rubber, enables the multilayer structure (1) to have good performance in terms of sound insulation and indentation resistance.

[0050] The upper layer (3) preferably has a thickness of between 1 and 6 mm. More preferably, the upper layer (3) has a thickness of between 1 and 3 mm in order to have good wear resistance while limiting the cost of manufacturing the multilayer structure (1).

[0051] In a known manner, the upper face of the backing layer (2) is bonded to the upper layer (3) produced from polyvinyl chloride.

[0052] According to the invention, and in order to facilitate the bonding operation, with an acrylic-based adhesive for example, and in particular in order to guarantee optimal resistance to the current pull-off test, said upper face of the backing layer (2) has a surface tension of greater than or equal to 40 mN/m. The surface tension is defined according to standard ISO 8296-2003.

[0053] Likewise, in order to facilitate the bonding of the lower face of the backing layer (2), in particular when it is being bonded to concrete or fiber cement, said lower face of the backing layer (2) also has a surface tension of greater than or equal to 40 mN/m.

[0054] In order to obtain this surface tension value, several solutions are possible.

[0055] According to a first embodiment, a surface treatment is carried out on the upper face, optionally on the lower face, of the backing layer (2), increasing their surface tension to a level greater than or equal to 40 mN/m.

[0056] For example, this surface treatment may consist of a surface treatment by fluorination, such as an oxyfluorination or a perfluorination.

[0057] Carrying out such a process for surface treatment by fluorination is visible on the final multilayer structure (1) since the thickness of the backing layer (2), and for example the first ten nanometers of thickness of the treated face, comprise fluorine atoms, for example at a content of greater than 3%, preferably greater than 5%.

[0058] During the fluorination process, the reactivity of the fluorine gas on the surface of the crosslinked polyolefin foam, or more specifically of the crosslinked polyethylene foam, leads to the substitution of hydrogen atoms by fluorine atoms, thereby improving the adhesion of the adhesive, and in particular of an acrylic-based adhesive.

[0059] In order to verify the fluorine content on the treated face, said face is for example analyzed by X-ray photoelectron spectroscopy.

[0060] The analytical conditions are as follows:

[0061] XPS on NOVA KRATOS apparatus

[0062] ANALYTICAL CONDITIONS: Source: monochromatic Al K. With charge compensation. 150 watts for general spectra and 225 watts for high-resolution spectra. Area analyzed: 300 m700 m. Detection angle: normal (=0). Analyzed depth less than 10 nm in normal detection.

[0063] In these conditions, the analysis made it possible to detect, in the first 10 nanometers of the treated face, a content of fluorine atoms equal to 8.2%.

[0064] This fluorine content of 8.2% makes it possible for the treated face of the backing layer (2) to have a surface tension of greater than 40 mN/m, and in particular a surface tension of 52 mN/m. The method of measuring the surface tension is defined according to standard ISO 8296-2003.

[0065] In order to check the adhesion of the backing layer (2), tests were carried out with upper and lower faces of the backing layer (2) treated by fluorination and having a surface tension of 52 mN/m.

[0066] The tests carried out consist of measurements of pulling off the backing layer (2) bonded, on one side, to an upper layer (3) of plasticized PVC and filled with mineral fillers, and bonded, on the other side, to a fiber cement floor, in comparison with a backing layer (2) bonded under the same conditions but not treated with fluorine, i.e. having a surface tension of approximately 35 mN/m.

[0067] The pull-off test of the assembly of the multilayer structure (1) on the fiber cement support gives a mean force value of 0.1 daN/cm for the structure comprising an untreated backing layer (2).

[0068] The test carried out with a multilayer structure (1) comprising a backing layer (2), the upper and lower faces of which are treated, gives a mean force value of 1.3 daN/cm.

[0069] Consequently, it appears that the multilayer structure (1) comprising a backing layer (2) treated according to the invention has good adhesion, noting that the minimum value for the pull-off force required by the current standards must be 0.6 daN/cm.

[0070] Thus, the present invention makes it possible to facilitate the bonding of the backing layer (2) to an upper layer (3) of PVC, in particular by means of a conventional acrylic adhesive, while guaranteeing optimal bonding, and also easy laying of the assembly of the multilayer structure (1) since bonding becomes possible on a concrete or fiber cement slab, without changing processes or products conventionally used by flooring installers.

[0071] In order to obtain a surface tension of greater than or equal to 40 mN/m, another solution consists in subjecting the upper face of the backing layer, and optionally the lower face, to a corona treatment. Corona treatment consists of emitting a high-frequency electrical discharge toward the treated surface. It makes it possible to obtain a very high level of oxidation of the surface and to modify the wettability thereof in order to facilitate the attachment of the adhesive, in particular acrylic-based.

[0072] However, the effect of the corona treatment tends to degrade in a few weeks. The corona treatment is therefore rather used to bond the upper face of the backing layer (2) to the upper layer (3).

[0073] Several embodiments are conceivable for the multilayer structure (1), depending on the desired application.

[0074] For example, and with reference to FIG. 1, the upper layer (3) may in particular consist of a single wear layer (4) produced from polyvinyl chloride, optionally plasticized, and optionally filled with mineral fillers.

[0075] According to one embodiment, in particular illustrated in FIG. 2, the upper layer (3) may consist of a wear layer (4) linked to an intermediate layer (5), itself produced from PVC, optionally plasticized, optionally filled with mineral fillers.

[0076] According to another embodiment, in particular illustrated in FIG. 3, the upper layer (3) consists of a wear layer (4) linked to an decorative film (6) and to an intermediate layer (5), itself produced from polyvinyl chloride, optionally plasticized, optionally filled with mineral fillers. According to this embodiment, the wear layer (4) preferably has a thickness of between 0.3 and 1 mm. This makes it possible to adapt the wear layer depending on the resistance to traffic desired for the majority of applications, while limiting the manufacturing cost of the multilayer structure (1).

[0077] The invention lies in the fact that the upper face of the backing layer (2), intended to be in contact with PVC, has a surface tension of greater than or equal to 40 mN/m and, if the backing layer (2) is intended to be bonded to concrete or fiber cement, or any other material to which acrylic-based adhesive has mediocre adhesion, the lower face of the backing layer (2) also comprises a surface tension of greater than or equal to 40 mN/m.

[0078] It emerges from the foregoing that the invention does indeed provide a multilayer structure (1) for producing floor coverings, which has sound-insulating properties, while making it possible to optimize bonding with an acrylic adhesive of a crosslinked polyolefin foam to PVC, concrete or fiber cement, while making it possible to withstand current pull-off tests and while having a good indentation resistance.