TEXTILE STRUCTURE BASED ON GLASS FIBERS FOR ACOUSTIC CEILING OR ACOUSTIC WALL PANEL

Abstract

The invention relates to a textile structure, intended to be used as a sound-absorbing structure in acoustic ceiling panels and/or acoustic wall panels, consisting of (a) a nonwoven mat of glass fibers bound by a thermoset binder, the nonwoven mat having a surface density of between 20 and 200 g/m.sup.2 and (b) a continuous acoustic layer comprising from 80% to 95% by weight of particles, preferably mineral particles, and from 5% to 20% by weight of a thermoplastic polymer and/or elastomer binder, the textile structure having an open porosity of greater than 3%, preferably between 4% and 60%, and a static airflow resistance (determined according to the standard ISO 9053) of between 1000 and 3000 N.Math.s.Math.m.sup.−3, said continuous acoustic layer at least partially impregnating said nonwoven mat, and the particle size distribution of the particles having a D.sub.10 of between 0.1 and 0.5 μm.

It also relates to a process for manufacturing such a textile structure and to a ceiling panel or wall panel coated on one of these faces with such a textile structure.

Claims

1. A textile structure, consisting of: (a) a nonwoven mat of glass fibers bound by a thermoset binder, wherein the nonwoven mat has a surface density of between 20 and 200 g/m.sup.2; and (b) a continuous acoustic layer comprising from 80% to 95% by weight of particles and from 5% to 20% by weight of an elastomer and/or thermoplastic polymer binder, wherein the textile structure has an open porosity of greater than 3%, and a static airflow resistance, determined according to the standard ISO 9053 of between 1000 and 3000 N.Math.s.Math.m.sup.−3, wherein said continuous acoustic layer at least partially impregnates said nonwoven mat, and wherein a particle size distribution of the particles has a D.sub.10 of between 0.1 and 0.5 μm.

2. The textile structure as claimed in claim 1, wherein the continuous acoustic layer has a surface density of between 100 g/m.sup.2 and 400 g/m.sup.2.

3. The textile structure as claimed in claim 1, wherein the nonwoven mat has a surface density of between 25 and 150 g/m.sup.2.

4. The textile structure as claimed in claim 1, wherein the particles are mineral particles.

5. The textile structure as claimed in claim 1, wherein at least 90% by number of the glass fibers forming the nonwoven mat have a length of between 5 mm and 12 cm.

6. The textile structure as claimed in claim 1, wherein the glass fibers forming the nonwoven mat have an average diameter of between 3 and 30 μm.

7. A process for manufacturing a textile structure as claimed in claim 1, comprising applying a layer of an aqueous impregnating composition to at least one face of a nonwoven mat of glass fibers bound by a thermoset binder, wherein the nonwoven mat has a surface density of between 20 and 200 g/m.sup.2, and wherein the aqueous impregnating composition comprises a mixture of 80% to 95% by weight of solids of particles and of 5% to 20% by weight of solids of a thermoplastic polymer and/or elastomer binder in latex form, wherein the aqueous impregnating composition has a solids content of between 35% and 70% by weight and wherein a particle size distribution of the particles has a D.sub.10 of between 0.1 and 0.5 μm, and drying and/or crosslinking the layer of the aqueous impregnating composition so as to obtain a continuous acoustic layer comprising from 80% to 95% by weight of particles and from 5% to 20% by weight of an elastomer binder.

8. The process as claimed in claim 7, wherein the nonwoven mat has a loss on ignition of between 5% and 40% by weight.

9. The process as claimed in claim 7, wherein the nonwoven mat has a static airflow resistance, determined according to the standard ISO 9053, of less than 50 N.Math.s.Math.m.sup.−3 and an air permeability of between 5000 and 6000 L/(m.sup.2.Math.s).

10. The process as claimed in claim 7, wherein the aqueous impregnating composition has a solids content of between 45% and 70% by weight.

11. The process as claimed in claim 7, wherein the particle size distribution of the particles is a bimodal or multimodal distribution, with a first mode located between 0.5 and 2.0 μm and a second mode located between 4 and 25 μm.

12. The process as claimed in claim 7, wherein the elastomer latex is a styrene-butadiene rubber (SBR)-based latex.

13. A laminated acoustic ceiling panel or acoustic wall panel, comprising: a board made of a rigid material comprising a plurality of perforations; and a textile structure as claimed in claim 1, bonded to a single face of the perforated board so as to seal all of the perforations.

14. The laminated panel as claimed in claim 13, wherein the rigid material of the board is at least one selected from the group consisting of plaster, a metal, and a plastic.

15. The textile structure as claimed in claim 1, wherein the textile structure has an open porosity between 4% and 60%.

16. The textile structure as claimed in claim 1, wherein the continuous acoustic layer has a surface density of between 150 g/m.sup.2 and 350 g/m.sup.2.

17. The textile structure as claimed in claim 1, wherein the nonwoven mat has a surface density of between 30 and 100 g/m.sup.2.

18. The textile structure as claimed in claim 4, wherein the mineral particles are: based on at least one selected from the group consisting of titanium oxide, magnesium oxide and/or aluminum oxide; made of calcium carbonate; or selected from the group consisting of kaolins, dolomites, and talcs.

19. The textile structure as claimed in claim 1, wherein at least 90% by number of the glass fibers forming the nonwoven mat have a length of between 1 cm and 11 cm.

20. The textile structure as claimed in claim 1, wherein the glass fibers forming the nonwoven mat have an average diameter of between 5 and 20 μm.

Description

EXAMPLES

[0064] Several aqueous impregnating compositions are prepared by dispersing in water calcium carbonate particles of different particle sizes and a styrene-butadiene latex. To obtain a good dispersion of the calcium carbonate particles in water, around 0.2% by weight (solids) of an anionic surfactant (Dowfax 2A1, alkyldiphenyloxide disulfonate) is added to the dispersion

[0065] The calcium carbonate powders are obtained from the company Mikhart.

TABLE-US-00001 D.sub.50 D.sub.98 Mikhart ® MU12 (MU12) 1.2 μm 6 μm Mikhart ® 5 (M5) 5 μm 20 μm Mikhart ® 10 (M10) 9 μm 45 μm Mikhart ® 15 (M15) 17 μm 125 μm

[0066] The mixture thus obtained is stirred for 10 minutes at 500 rpm, then 0.2% by weight (solids) of hydroxyethyl cellulose (Tylose®), which acts as thickener, is introduced therein. It is mixed again for 10 minutes at 2000 rpm.

[0067] Thus aqueous impregnating compositions of homogeneous appearance are obtained that contain 8.1% by weight (of solids) of styrene-butadiene latex and 91.5% by weight (of solids) of calcium carbonate particles.

[0068] These compositions are deposited by knife coating on a nonwoven mat of glass fibers having a surface density of 50 g/m.sup.2.

[0069] The nonwoven mat thus coated is dried for 2 minutes at a temperature of 180° C. The acoustic textile structures obtained have a surface density of between 140 and 350 g/m.sup.2.

[0070] Next the open porosity and the static airflow resistance of the textile structures thus prepared are determined.

[0071] All the textile structures have an open porosity of between 10% and 50%.

[0072] Table 1 shows the static airflow resistance (according to ISO 9053) for various mixtures of mineral particle powders and for various solids contents of the impregnating compositions.

TABLE-US-00002 TABLE 1 Static CaCO.sub.3 Weight Solids Viscosity resistance powder ratio (%) (Pa .Math. s) (N .Math. s .Math. m.sup.−3) 1* MU12 100 46.6 29 1800 2* MU12 100 37 11 1491 3  MU12 100 30.9 9.8 749 4* MU12 + M5  15/85 61.8 16.5 1857 5* MU12 + M5  25/75 61.8 25.3 2217 6* MU12 + M5  40/60 61.8 25.1 2020 7  MU12 + M5  25/75 46.6 17.7 168 8  MU12 + M10 15/85 61.8 10.7 922 9* MU12 + M10 20/80 61.8 10.2 1797 10*  MU12 + M10 25/75 61.8 11.7 2475 11  MU12 + M15 25/75 61.8 10.9 880 12*  MU12 + M15 30/70 61.8 12.6 1198 13*  MU12 + M15 40/60 61.8 19.9 2515 *according to the invention

[0073] Samples 1-3 show that for a powder having a unimodal particle size distribution consisting of very fine particles, the reduction in the water content of the impregnating composition leads to a reduction in the static airflow resistance of the acoustic layer.

[0074] Samples 4-6 show that it is possible to replace a portion of the particles of very small size with larger, cheaper particles, as long as the solids content of the compositions is increased.

[0075] Comparison of samples 1 and 7 shows that replacing very small particles (MU12) with larger particles (M5) leads to a significant reduction in the static airflow resistance.

[0076] The series of samples 8-10 shows that for a bimodal distribution of calcium carbonate particles (MU12+M10) the static airflow resistance is higher, the greater the fraction of very small particles (MU12).

[0077] This tendency is confirmed again by the series of samples 11-13.

[0078] These application examples show that it is possible to adjust the airflow resistance by acting on the solids content and/or on the particle size distribution of the mineral particles.