WO2009039900A1

WO2009039900A1 - Acoustic nonwoven fabric for perforated ceiling elements

Info

Publication number: WO2009039900A1
Application number: PCT/EP2008/003759
Authority: WO
Inventors: Holger Schilling; Jochen Bechtum; Gerhard Stuppy; Günter Frey
Original assignee: Carl Freudenberg Kg
Priority date: 2007-09-19
Filing date: 2008-05-09
Publication date: 2009-04-02
Also published as: RU2010115335A; CN101809222B; US20100304109A1; EP2191058B1; EP2191058A1; CN101809222A; DK2191058T3; BRPI0816874A2; DE102007044906A1; RU2447240C2; ES2376506T3; ATE538239T1

Abstract

The aim of the invention is to design an acoustic nonwoven fabric which can be processed without any problem and develops as little smoke as possible in case of a fire. Said aim is achieved by a layer for use in a metal ceiling. Said layer has a maximum mass per unit area of 45 g/m² and comprises a maximum of 30 g/m² of a fiber mixture and a maximum of 10 g/m² of a flame retardant.

Description

Applicant: Carl Freudenberg KG, 69469 Weinheim

Acoustic nonwoven for perforated ceiling elements

description

Technical area

The invention relates to a layer for producing an acoustic nonwoven fabric.

State of the art

Acoustic nonwovens and layers of the type mentioned are already known from the prior art. These are often used in perforated, namely perforated or slotted, metal ceiling or wooden ceiling elements.

With regard to their fire behavior, such acoustic nonwovens or ceiling elements have hitherto been assessed in accordance with DIN 4102-1 by means of a so-called "fire shaft test". In doing so, both the acoustic nonwoven fabric itself and the composite with the ceiling element had to be tested. The market demanded a classification into fire class "A2"("non-combustible") from the composite of ceiling element and acoustic non-woven fabric. From the acoustic nonwoven fabric as such, a classification in the Brandkiasse "B1" (= "flame retardant") was required. Since July 2007, a revised, EU-standard regulation concerning the certification and classification of suspended ceilings is in force, namely the CE mark. This regulation places requirements on the ceiling elements, which are laid down in DIN EN 13964, which refers to DIN EN 13501-1 with regard to the classification of fire behavior.

The fire behavior test is no longer carried out in accordance with DIN 4102-1 ("fire shaft test"), but in accordance with DIN EN 13823. This standard describes a so-called "SBI test" ("single burning item" test) a complete ceiling element structure and defines the classification relevant parameters according to DIN EN 13501-1. In contrast to the previous test of fire behavior according to DIN 4102-1, the test in accordance with DIN EN 13823 is increasingly aimed at assessing smoke release in the event of fire. The release of smoke is evaluated in stricter standards in DIN 13501-1 than before.

Acoustic nonwovens known from the prior art tend to generate relatively strong smoke and thus prevent classification of ceiling elements as "non-combustible" (classification "A2 / s1 / dθ") in accordance with the revised requirements of DIN 13501-1. However, this classification is particularly relevant to buildings having increased safety requirements, e.g. public buildings, escape routes, etc., demanded.

In addition, the acoustic nonwoven fabric should form a high acoustic efficiency, namely achieve a singular value α _w of at least 0.75 from a sound absorption coefficient measurement according to EN ISO 354 or conversion to EN ISO 11654.

Furthermore, it is desirable to have a simple processability, in particular a space-saving handling or automated introduction into Ceiling elements. Finally, the acoustic non-woven fabric must not adversely affect hygiene, health and environmental aspects.

Accordingly, there is a considerable need in the market for readily processable acoustic nonwovens which, in combination with ceiling elements, fulfill the classification "A2 / s1 / d0" according to DIN EN 13501-1.

Presentation of the invention

The invention is therefore based on the object to provide an acoustic nonwoven fabric that shows the least possible smoke development in case of fire after easy processing.

According to the invention the above object is achieved with the features of claim 1.

Thereafter, a flat layer with a basis weight of at most 45 g / m ² comprises a fiber mixture which is present in a proportion of at most 30 g / m ² , and a flame retardant which is present in a proportion of at most 10 g / m ² .

According to the invention, it has been recognized that it is precisely the combination of a skilful choice of the total weight per unit area and an adapted reduction of the flame retardant that brings about a considerable reduction in the development of smoke. The layer according to the invention is in a special way provided with an adhesive mass for arrangement in a metal ceiling element. Consequently, the object mentioned above is achieved.

The impregnating mixture could include diammonium hydrogen phosphate as a flame retardant which contains halogen and heavy metals and thus is environmentally friendly. However, it is also conceivable to use other nitrogen-phosphorus-based flame retardants, for example ammonium polyphosphates or nitrogen-containing phosphonic acid salts.

The fiber mixture could have fine-fiber or fibrillated cellulosic components. These components are used to tune the acoustic effectiveness of the situation. Against this background, it is conceivable that the fiber mixture contains two different types of cellulose, which are matched with regard to their fineness. However, it is also conceivable to use finely ground synthetic pulps, e.g. made of viscose, polyolefin or aramid fibers.

The fiber mixture could also comprise fibers of glass, which are present in a proportion of at most 10 g / m ² . This proportion of glass fibers gives the sheet high structural stability and low thermal shrinkage. This is the location for an automated insertion into ceiling elements. However, it is also conceivable to use other inorganic fibers, for example fibers of basalt or aluminum oxide. Finally, polyester fibers could also be used.

The fiber blend may be pre-bonded with a binder based on acrylate with a proportion of less than 5 g / m ^2. The pre-binding gives the layer sufficient stability to homogeneously introduce an impregnating mixture. Against this background, it is conceivable that the pre-binding takes place by means of a low-formaldehyde acrylate binder. As a result, increased requirements are met in terms of the formaldehyde content of the situation according to DIN EN 13964 (formaldehyde class "E1"). Also conceivable is pre-binding with the aid of a mono- or bicomponent binder fiber, for example with a so-called undrawn polyester fiber or a PET / PBT or PET / copolyester-bicomponent binder fiber. An acoustic nonwoven fabric for metal ceilings having a basis weight of less than 60 g / m ² could have a layer of the type described herein and an adhesive mass wherein the adhesive mass is present at less than 15 g / m ² . The adhesive composition makes it possible to fix the acoustic nonwoven fabric under moderate heating in a metal ceiling element, without damaging components of the ceiling element, such as a lacquer layer. Against this background, it is conceivable that the adhesive composition consists of a thermoplastic, largely amorphous polyester, copolyester or copolyamide having a melting point below 100 ⁰ C.

The acoustic nonwoven fabric could have a singular value α _w of at least 0.75, the single value being obtained according to a sound absorption coefficient measurement according to EN ISO 354 and after conversion according to EN ISO 11654. Such an acoustic nonwoven absorbs sound particularly well.

An arrangement comprising a layer or an acoustic nonwoven fabric of the type described here and an unpainted perforated metal ceiling element could, in a measurement according to DIN EN 13823, have an SMOGRA value of at most 30 m ² / s ² and a TSP (600s) value of show at most 50 m ² . Such an arrangement is suitable not only for sound insulation, but also for fire protection in particular.

There are now various possibilities for embodying and developing the teaching of the present invention in an advantageous manner. For this purpose, on the one hand to the subordinate claims, on the other hand, to refer to the following explanation of the invention with reference to the drawings. Brief description of the drawing

In the drawing shows the only one

Fig. A diagram showing the by testing according to DIN EN

No. 13823, comparing smoke development of a ceiling element construction with a nonwoven acoustic fabric of the prior art with the smoke development of an analog ceiling element structure with an acoustic nonwoven fabric according to the invention.

Embodiment of the invention

The sole FIGURE is a diagram comparing a ceiling element construction with a sample of a prior art acoustic nonwoven fabric having a ceiling element construction with a sample of an acoustic nonwoven fabric according to the present invention. To do this:

The samples of the prior art are indicated by the broken lines and the square symbol. The curves for the sample according to the invention are indicated by the solid lines and the circle symbol.

The SPRav curves or the individual SPRa _V (t) values ("Smoke Production Rate", left y-axis, unit [m ² / s]) represent the current smoke development of the samples at time t of the measurement (resp. within a differential time interval [t, t-3s]). An SPRav value represents the quotient of a flue gas volume flow in [m ³ / s] and the length in [m] of the light path through the tube of a photometric measuring device, resulting in the unit [m ² / s]. The TSP curves or the individual TSP (t) values ("Total Smoke Production", right y-axis, unit [m ² ]) represent the total smoke development of the samples up to time t of the measurement. A TSP (t) value corresponds to the sum of the individual SPRav (t) values in the time interval from the beginning of the measurement to the time t or corresponds to the associated area under the SPR curve. A TSP value represents the product of a sum of SPR ₃ V values in [m ² / s] and the associated time interval in [s], resulting in the unit [m ² ].

With regard to the entire test duration with so-called "pre-run" and "post-run", the SPRav or TSP values of a sample within the time window from 300 s to 900 s are measured or used for the evaluation. Therefore, the time axis is scaled from 300 s to 900 s. The zero point of the actual measurement is therefore 300 s based on the entire test duration.

The TSP (600s) values ("Total Smoke Production", unit [m ² ]) represent the total smoke development of the samples in the first 600 s of the measurement. According to the timeline scaling notes above, they correspond to the symbol-marked points on the TSP curves at time t = 900 s with respect to the total test duration.

The SMOGRA values ("SMOke GRowth RAte index", unit [nr ^ / s ² ]) represent the maxima of the quotients from the SPRa _V (t) values of the samples and the associated times t of the measurement. They characterize, to some extent, the slopes of the SPRav curves at the beginning of the measurement ("slope triangles"). The SMOGRA value represents the quotient of an SPRa _V (t) value in [m ² / s] and the associated time t in [s], resulting in the unit [nrvVs ² ]. In accordance with DIN EN 13823, a quotient of an SPRav (t) value and the associated time t of the measurement is to be regarded as 0 by definition if the following boundary conditions are fulfilled for the determination of the SMOGRA value:

(a) the SPRav (t) value is less than or equal to 0.1 m ² / s, or

(b) the associated TSP (t) value is less than or equal to 6 m ²

This means: If the SPRav curve does not exceed 0.1 m ² / s or if the associated TSP (t) values do not exceed 6 m ² at times and in this time interval, all quotients of SPRav (t) Values and associated times t of the measurement to be evaluated as 0 and thus also to regard the SMOGRA value as 0 by definition.

However, in order to be able to reasonably evaluate even low-smoke samples or to compare them, the SMOGRA values were determined neglecting the boundary condition (a).

In order to be able to evaluate only the influence of the samples of acoustic nonwoven fabric on the smoke development, constructions of ceiling elements made of perforated steel sheets without coating or other smoke-relevant components according to DIN EN 13823 were generally measured. This is to disturbing influences by other components of the ceiling element, such. a lacquer layer can be eliminated.

In terms of smoking behavior, according to DIN EN 13501-1, the SMOGRA value and the TSP (600s) value are decisive parameters for determining a "smoke class" (s1, s2 or s3). In order to achieve the above-mentioned "non-combustible" classification "A2 / s1 / dθ", which includes the "smoke class" s1 and thus makes the highest demands on the smoking behavior, the following limits for the abovementioned smoke-relevant parameters must be observed: SMOGRA value smaller or equal to 30 m ² / s ² and TSP (600s) value less than or equal to 50 m ² . Measurements of the type of ceiling element structures described here demonstrate that a sample of the prior art acoustic nonwoven fabric provides an SMOGRA value of about 30 m ² / s ² and a TSP (600s) value of about 40 m ² . This is shown in the diagram of the single FIG.

In contrast, a sample of the acoustic nonwoven fabric according to the invention shows only an SMOGRA value of about 15 m ² / s ² and a TSP (600s) value of about 30 m ² , ie an SMOGRA value reduced by about 50% and a reduced by about 25% TSP (600s) value.

Reference measurements on similar ceiling element structures without acoustic nonwoven, but with a coating, show that commercially available coatings make a first approximate additive contribution to the SMOGRA value of at best about 10 m ² / s ² , usually of about 15 - 20 m ² / s ² , and contribute to the TSP (600s) value of at best about 15 m ² , usually about 20-30 m ² .

Thus, SMOGRA values of at best approx. 40 nrvVs ² or TSP (600s) values of at best approx. 55 nrvVs ² result for standard ceiling element structures with a coating and an acoustic nonwoven fabric according to the prior art. These high values prevent a "non-combustible" classification "A2 / s1 / dθ" according to DIN EN 13501-1.

On the other hand, for ceiling element constructions with an acoustic nonwoven according to the invention with optimum execution of the coating, SMOGRA values of only about 25 m ² / s ² or TSP (600s) values of only about 45 m ² / s ^{2 result} . These values allow a "non-combustible" classification "A2 / s1 / dθ" according to DIN EN 13501-1. Example according to the prior art:

A prior art acoustic nonwoven fabric consists of a ply and an adhesive. The weight per unit area is 63 g / m ² . The basis weight of the layer is 48 g / m ² and the weight per unit area of the adhesive mass is 15 g / m ² .

The sheet has a fiber blend of pulp fibers and glass fibers. The fiber mixture contributes with a total of 25 g / m ² to the basis weight of the situation.

The layer furthermore has a fiber binding of acrylate binder with a basis weight contribution of 4 g / m ² .

The layer also has an impregnating mixture with a flame retardant, which makes up a basis weight contribution of 14.5 g / m ² . The impregnation mixture also contains a colorant of carbon black and an ethyl vinyl alcohol binder, which together make up a basis weight contribution of 4.5 g / m ² .

The adhesive consists of epsilon - polycaprolactone.

Embodiment according to the invention:

An acoustic fleece according to the invention consists of a layer and an adhesive. The basis weight is 54 g / m ^{2 in} total. The basis weight of the layer is 42 g / m ² and the basis weight of the adhesive mass 12 g / m ² .

The sheet has a fiber blend of fibers of two types of pulp and glass fibers. The fiber mixture contributes with a total of 26 g / m ² Basis weight of the situation at. The fibers of pulp account for 20 g / m ^{2 of} the basis weight of the layer, the glass fibers 6 g / m ² .

The layer also has an impregnating mixture with a flame retardant, which constitutes a basis weight contribution of 7.5 g / m ² . The impregnation mixture also contains a colorant of carbon black and an ethyl vinyl alcohol binder, which together make up a basis weight contribution of 4.5 g / m ² .

The adhesive used was epsilon-polycaprolactone.

With regard to further advantageous embodiments and developments of the teaching of the invention reference is made on the one hand to the general part of the description and on the other hand to the claims.

Finally, it should be particularly emphasized that the previously purely arbitrarily selected embodiment is only for the purpose of discussing the teaching of the invention, but this does not limit this embodiment.

Claims

claims

A layer for use in a ceiling element, having a basis weight of at most 45 g / m ² , comprising a fiber mixture which is present in a proportion of at most 30 g / m ² and a flame retardant, which in a proportion of at most 10 g / m ² present.

2. Layer according to claim 1, characterized in that the flame retardant consists of Diammoniumhydrogenphosphat.

3. Layer according to claim 1 or 2, characterized in that the fiber mixture comprises fibers of cellulose.

4. Layer according to one of claims 1 to 3, characterized in that the fiber mixture comprises fibers of two different types of pulp.

5. Layer according to one of claims 1 to 4, characterized in that the fiber mixture comprises fibers made of glass, which are present in a proportion of at most 10 g / m ² .

6. Layer according to one of claims 1 to 5, characterized in that an acrylic-based binder is present in a proportion of less than 5 g / m ² .

7. An acoustic nonwoven fabric for metal ceilings with a basis weight of less than 60 g / m ² , comprising a layer according to any one of the preceding claims and an adhesive mass, wherein the adhesive composition is present in a proportion of less than 15 g / m ² .

8. Acoustic nonwoven fabric according to claim 7 or layer according to one of claims 1 to 6, characterized by a singular value α _w of at least 0.75, wherein the singular value is obtained from measurement according to EN ISO 354 and conversion according to EN ISO 11654.

9. Arrangement comprising a layer according to one of claims 1 to 6 or an acoustic nonwoven fabric according to claim 7 or 8 and an unpainted, perforated metal ceiling element, which in a measurement according to DIN EN 13823 an SMOGRA value of at most 30 m ² / s ² and a TSP (600s) value of at most 50 m ² .