MINERAL FIBRE REINFORCEMENT FOR FLEXIBLE FLOOR COVERING SLABS

Abstract

A mat/mesh laminate for flexible floor covering slabs is formed by a glass fiber mat, bonded by a first organic polymer, having an air permeability, measured in accordance with standard NF EN ISO 9237 at a pressure of 200 Pa, of between 6000 and 12,000 l/m.sup.2.Math.s, and by a glass yarn mesh having a titer of between 30 and 150 tex that is coated with a second organic polymer.

Claims

1. A mat/mesh laminate, formed by a glass fiber mat, bonded by a first organic polymer, having an air permeability, measured in accordance with standard NF EN ISO 9237 at a pressure of 200 Pa, of between 6000 and 12,000 l/m.sup.2.Math.s, and by a glass yarn mesh having a titer of between 30 and 150 tex that is coated with a second organic polymer.

2. The mat/mesh laminate according to claim 1, wherein the glass yarn mesh is adhesively bonded to the glass fiber mat by means of the second organic polymer.

3. The mat/mesh laminate according to claim 1, wherein the glass fibers forming the glass fiber mat have a diameter of between 12 and 17 ?m, and a length of between 12 and 25 mm.

4. The mat/mesh laminate according to claim 1, wherein the glass fiber mat has a mass per unit area of between 25 and 50 g/m.sup.2.

5. The mat/mesh laminate according to claim 1, wherein the glass fiber mat has a thickness of between 250 ?m and 500 ?m.

6. The mat/mesh laminate according to claim 1, wherein the glass yarn mesh consists of weft yarns and warp yarns all having the same titer.

7. The mat/mesh laminate according to claim 1, wherein a density of the weft yarns and warp yarns is between 3 and 4 yarns/cm.

8. The mat/mesh laminate according to claim 1, wherein the glass yarns have between 10 and 30 twists/m.

9. The mat/mesh laminate according to claim 1, wherein the laminate has a mass per unit area of between 70 and 150 g/m.sup.2, and a thickness of between 0.45 and 0.80 mm.

10. The mat/mesh laminate according to claim 1, wherein the mesh is a knitted mesh, a woven mesh or a spun mesh.

11. A flexible floor covering slab based on poly(vinyl chloride) (PVC) comprising, as single reinforcement, a mat/mesh laminate according to claim 1.

12. The flexible floor covering slab according to claim 11, comprising: a base layer including an upper face and a lower face, said base layer consisting of a mat/mesh laminate according to claim 1 and of two layers made of plasticized PVC in contact respectively with the two faces of the mat/mesh laminate, a decorative layer printed on the upper face of the base layer, a transparent wear layer, covering the decorative layer printed on the upper layer of the base layer.

13. The flexible floor covering slab according to claim 11, further comprising a support layer, in contact with the lower face of the base layer.

14. The flexible floor covering slab according to claim 11, wherein the base layer has a total thickness of between 0.8 and 2.8 mm and wherein the transparent wear layer has a thickness of between 0.1 mm and 1.0 mm.

15. The mat/mesh laminate according to claim 4, wherein the glass fiber mat has a mass per unit area of between 30 and 45 g/m.sup.2.

16. The mat/mesh laminate according to claim 15, wherein the glass fiber mat has a mass per unit area of between 32 and 39 g/m.sup.2.

17. The mat/mesh laminate according to claim 5, wherein the glass fiber mat has a thickness of between 270 ?m and 400 ?m.

18. The mat/mesh laminate according to claim 8, wherein the glass yarns have from 15 to 28 twists/m.

19. The mat/mesh laminate according to claim 9, wherein the laminate has a mass per unit area of between 75 and 120 g/m.sup.2 and a thickness of between 0.50 and 0.75 mm.

20. The mat/mesh laminate according to claim 10, wherein the mesh is a knitted mesh.

Description

EXAMPLES

[0061] A slab A according to the invention and a comparative slab B were prepared, having the following technical characteristics:

Slab A:

[0062] PVC base layer reinforced by a mat/mesh laminate with a nonwoven mat of glass fibers E having a length of 18 mm and a diameter of 13 ?m, bonded by a urea/formaldehyde binder, mass per unit area of 35 g/m.sup.2, LOI 20%, air permeability 9200 l/m.sup.2.Math.s at 200 Pa, and a knitted mesh (density 3.5 yarns/cm; 34 tex (warp); 68 tex (weft); acrylic binder). The total thickness of the slab (including wear layer, base layer and support layer) is 4 mm.

Slab B:

[0063] PVC base layer reinforced by a nonwoven mat of glass fibers E having a length of 18 mm and a diameter of 13 ?m, bonded by a urea/formaldehyde binder, mass per unit area of 35 g/m.sup.2, LOI 20%, air permeability 9200 l/m.sup.2.Math.s at 200 Pa. The thickness of the slab (including wear layer, base layer and support layer) is 4 mm.

[0064] The thermal expansion of these two slabs is measured as follows by dynamic mechanical thermal analysis (DMTA) using a DMTA apparatus, model Q800 from TA Instruments:

[0065] The PVC slab is cut into samples of 25 mm?6 mm (in the longitudinal (warp) and transverse (weft) direction). The sample is attached between two jaws of the DMTA apparatus that place the sample under tensile stress, then an oven is closed around the sample. The sample is then subjected to a periodic mechanical tensile stress: deformation of 0.001%, frequency 1 Hz.

[0066] The sample is first cooled at a rate of 2? C./min from room temperature to 5? C., then heated at a rate of 1? C./min to 50? C., and cooled again to the temperature of 5? C. at a rate of 2? C./min. The heating/cooling cycle is carried out 3 times in total for each sample.

[0067] During the second and third cycle, the increase in the length of the sample is recorded between 12? C. (L12) and 38? C. (L38), and the expansion is calculated over this temperature range according to the following formula:

[00001]$\mathrm{Expansion}\left(\%\right)\text{:}100?\left(L_{38}-L_{12}\right)/L_{12}$

[0068] The results correspond to the mean calculated over the two heating/cooling cycles.

[0069] For the slab A according to the invention, the thermal expansion is 0.13% in the direction of the 34 tex warp yarns (machine direction) and between 0.11 and 0.14% in the direction of the 68 tex weft yarns (cross-machine direction).

[0070] For comparative slab B, thermal expansion is 0.19% in the warp direction (machine direction) and 0.22% in the weft direction (cross-machine direction).

[0071] These results show that the use of glass fiber mat/glass yarn mesh laminate according to the invention makes it possible to effectively limit the thermal expansion of the flexible slabs compared to identical slabs reinforced by a simple nonwoven glass fiber mat.

[0072] The slabs do not exhibit any problems of delamination.