Sound-damping profiled member

Translation of description of equivalent WO 2004012952 A2

PROFILE A PROPERTY DEPRECIATION ACOUSTIC

The present invention relates to a profile designed to be inserted between two elements to achieve acoustic attenuation of the noise propagating through at least one of the elements, the strip being constituted by at least one damping material i to plastic-based .

Such a profile can be used in particular for panes of the vehicle, in particular automobile, in order to improve the acoustic comfort.

In a motor vehicle, the sources of annoyance of mechanical, thermal, visibility, etc .. have been gradually mastered. But improving the acoustic comfort is still relevant.

The noise of aerodynamic origin, that is to say created by the friction of the air on the moving vehicle, could, at least in part, be treated themselves to their source, that is, -dire that to save power, the forms were changed thus improving penetration through the air and reducing the turbulence which are themselves a source of noise. Among the walls of a vehicle that separate the source of external aerodynamic noise from the interior space where the passenger is located, the windows are obviously more difficult to treat. We can use pasty or fibrous absorbent reserved for opaque walls and for practical or weight reasons, thicknesses can not be increased indiscriminately. European Patent EP-B1-0 387 148 glazing that achieve good insulation against noise of aerodynamic origin without their weight and / or thickness are increased too. The patent proposes a laminated glazing whose interlayer has a flexural damping v = Df / f_c greater than 0.15, as measured by exciting by a shock, a laminated bar of 9 cm length and 3 cm in width made of a laminated glass in which the resin is between two thick glass each 4 mm, and by measuring f_0> resonant frequency of the first mode, and .DELTA.f, peak width at an amplitude AΛ / 2 where A is the maximum amplitude at frequency f_c of such so that its acoustic attenuation index does not differ for any of the frequencies above 800 Hz by more than 5 dB from a reference index increasing by 9 dB per octave up to 2000 Hz and 3 dB per octave at higher frequencies . In addition, the standard deviation σ of the differences in its acoustic attenuation index relative to the benchmark index remains below 4 dB. The thicknesses of the two lenses can be identical and equal to 2.2 mm. This patent proposes a general solution to the problem of sound insulation of the aerodynamic noise of a vehicle.

By cons, the treatment of glazing against the original structure-borne noise, that is to say against noise transmitted via solid and in the frequency range of 50 to 300 Hz or 800 Hz, is more difficult to achieve. Indeed, it appears that the use of connecting parts is insufficient to prevent the transmission of noise by vibration of the glass. It was found, for this purpose, at certain engine speeds, a hum in the passenger appeared and thus causing a source of annoyance. Indeed, the engine rotation causes the creation of vibrations that are transmitted, for example, to the body and thus by chain effect, to glazing. We know that the energy acquired by an object subjected to a shock causes a vibration phenomenon and immediately after the shock, the object become free vibrates in its own way. Each mode has a frequency of vibration. The amplitude of the vibration depends on the initial excitation, that is to say, the spectral component of the shock (amplitude of the shock at the frequency studied) and the impact zone of the shock, the modal deformation being more or less important depending on whether the shock occurs at a stomach or a vibration node.

For a natural mode to be excited, you must:

(1) the deformation caused at the impact point is not located on a vibration mode node,

(2) the shock energy spectrum have a component at the resonant frequency of the mode.

This latter condition is practically always satisfied because a very brief shock has a virtually uniform energy spectrum.

The first condition is met and, for a bar free at its ends, for example, just type in one of the ends to excite all modes. The structure-borne excitation is peripheral and it has been shown that certain frequencies of vibration of the engine, that is to say at certain engine speeds, the windows and the vehicle cabin each had a fashion vibration, the coupling amplified the buzz, from the radiation of noise from the motor in this case, by the glass. Of course, the engine rotational speed causing these phenomena is specific to each vehicle type and can not be generalized in this way to a unique value.

Also, to improve the acoustic comfort in the passenger compartment vis-à-vis the structure-borne noise origin, EP 0844075 proposes laminated glazing comprising at least one intermediate film having damping qualities audible sounds original structure-borne very satisfactory as having a loss factor tanδ greater than 0.6 and a shear modulus G 'less than 2.10⁷ N / m², In a temperature range between 10 and 60 ° C.

Another solution may be to associate with the periphery of the glazing a profiled acoustic damping property. For this purpose, the DE 198 06 122 proposes a profile that achieves firstly the fixing of the window of the vehicle to the body and also plays a damping role. The profile is hollow and filled with a pasty material which has the function of damping the vibrations, the body of the section being made of a bonding material that becomes elastic after crosslinking.

However, the latter solution has the disadvantage of not providing sufficient stiffness to the profile to guarantee the desired acoustic performance.

Indeed, on the one hand, the described profile which is a coextruded cord is intended to be compressed between the glazing and the bodywork but this method of crushing by application linked to the constituent materials of the profile does not guarantee the desired final dimensional shape. Or preserve profile dimensions after fixing the glazing to the body by means of said section is essential in the damping performance to be played the profile as discussed in the description of the invention.

On the other hand, the inner pasty material to the body of the profile remains soft and its confinement after crushing the cord coextruded against the bodywork element is not guaranteed, because the body of the section consisting of the material Bonding is also pasty before crosslinking which creates the risk of depositing cord internal pasty material spreading beyond the body of the profile.

The invention therefore aims to provide such acoustic damping solution, particularly for motor vehicle glazing, a profile does not have the drawbacks of the prior art.

According to the invention, the profile is characterized in that it has a real linear equivalent stiffness K '_eq at least equal to 25 MPa and a loss factor tanδ equivalent_eq at least equal to 0.25.

The stiffness is a quantity that relates the deformations of the profile of the efforts applied to it. Stiffness is defined by the stiffness of the materials forming the strip and by the geometry of the profile, the rigidity being a characteristic of the material which depends on the Young's modulus and / or shear modulus. In the following description, the formulas for calculations are only related to the Young's modulus, shear modulus will not be considered, constraints and compression-tensile deformations related to the Young modulus is sufficiently representative .

As known, the equivalent linear stiffness K *_θq is a complex number is writing K^*_eq = K_eq K + j "_eq with the real part K '_eq, Called in the description of the real equivalent stiffness per unit length, and the imaginary part K "_eq which corresponds to power dissipation, that is to say the conversion of energy of deformation of the profile into heat energy throughout the profile. "

And the loss factor tanδ is defined by_eq = - -.

^Keq

For the equivalent real linear stiffness K '_eq and tanδ equivalent loss factor_eq a profile consisting of one or more materials, these quantities will be estimated using a viscosity analyzer, known apparatus for the art that is the acoustician and polymériste. The viscosity analyzer measures the real equivalent stiffness k '_eq and power dissipation equivalent k "_eq a section profile of sample identical to that of the section of length L and then perform the following calculations: - Ratio of the measured real equivalent stiffness and length L to obtain the real equivalent stiffness per unit length K '_eq the profile:

e Γ_q⁼ Eα K / L ^'

- Ratio of the equivalent measured power dissipation and measured real equivalent stiffness for the equivalent loss factor tanδe_q the profile: sl '

J £ eq

Advantageously, the profile has a real equivalent stiffness per unit length K '_eq between 30 MPa and 270 MPa and an equivalent loss factor tanδ_eq at least equal to 0.4.

According to a first embodiment, the profile consists of a single shock-absorbing material or several damping materials, or the damping materials can exhibit adhesive properties with both elements.

According to a second embodiment, the profile consists of at least one damping material and a non-damping bonding material, the bonding material being adapted to fasten together the two elements.

According to a feature of this second embodiment, the bonding material adheres by two faces opposite the two elements respectively, the damping material being made integral with at least one of the two elements.

According to another characteristic, the bonding material adheres to one of its faces to the absorbing material that is made integral with one of the elements, and adhered by its face opposite the other element to be associated.

According to another feature, the strip comprises several damping materials prepared by stacking according to the plies, one above another, each of the materials to stack the ends being made integral with one of the two elements to be joined or of the bonding material .

Alternatively, the strip comprises several damping material arranged in juxtaposition next to each other, edge-glued or not, each material having two opposing surfaces made integral with the two elements to be joined, respectively.

According to yet another variant, the profile comprises several damping materials prepared by stacking and juxtaposition, at least one or two materials partly constituting this combination being made integral with the two elements to be joined.

For all these alternatives, when the profile also includes the adhesive material, it may be arranged by stacking and / or juxtaposition with or damping materials. Nondamping the bonding material is for example a polyurethane sealant having a Young's modulus E 'equal to 21 MPa and a loss factor tanδ equal to 0.2.

According to one characteristic, the or damping materials among themselves or with the adhesive material are separated by an air gap.

Advantageously, the or damping materials are selected from the following plastics, plasticized polyvinyl chloride or non-thermoplastic elastomers, mono or two-component polyurethanes, modified or not by an elastomer such as polyolefins, EPDM (ethylene-propylene diene), or rubber, in particular butyl rubber, or nitrile, or styrene-butadiene, polyacrylates or polymethacrylates, copolymers of alkyl and epoxide resins.

In a first variant composition, the damping material is a monocomponent polyurethane whose percentage of NCO is between 0.5 and 2% and comprising

- At least one polyester polyol of functionality equal to two (preferably between 80 and 200 g), having a iOH index between 5 and 10, a lower glass transition temperature T or equal to -50 ° C and a softening point of 50 and 80 ° C,

- At least one polyester polyol of functionality equal to two (preferably between 120g and 220g) having an iOH index between 50 and 100, a lower glass transition temperature T or equal to -50 ° C,

- At least one isocyanate functionality of between 2.1 and 2.7 of the type diphenylmethane (MDI) and having a percentage of NCO of 11 to 33% (preferably between 180 and 220g)

- At least one catalyst (preferably between 0.5 and 3 g),

- Possibly a molecular sieve load (preferably between 20 and 60g)

- Optionally at least one type of load chalk, kaolin, talc, alumina, carbon black, graphite or (preferably between 5 and 60g). With such a composition, the profile consisting of one material has to

20 ° C, at a width of 15mm reference section and of 3 mm thickness, a real linear stiffness equivalent equal to 400 MPa and an equivalent loss factor of 0.3.

According to yet another variant composition of the damping material is a polyurethane prepolymer with a percentage of NCO is between

0.5 and 2%, the material comprising:

- At least one polyether polyol of functionality equal to two, having an iOH index between 25 and 35, a Tg transition temperature below -50 ° C, of ​​molecular weight between 3500 and 4500;

- At least one polyether polyol of functionality between 2.3 and 4, having a iOH index between 25 and 800, a glass transition temperature T less than -50 ° C;

- At least one polyester polyol of functionality equal to two, iOH having a value between 20 and 40, a Tg transition temperature between -40 and -20 ° C;

- At least a functionality equal to two polyester polyol having a iOH index between 30 and 90, a Tg transition temperature between 0 and 30 ° C and a softening point between 50 and 70 ° C;

- At least one isocyanate functionality of between 2.1 and 2.7 of the type diphenylmethane (MDI) and a percentage of NCO of 11 to 33%;

- At least one catalyst;

- Possibly a molecular sieve load; possibly a chalk load type, kaolin, talc, alumina, carbon black or graphite.

The profile has at 20 ° C with such a composition, in a reference section 15mm wide and 3 mm thick, a real linear stiffness equivalent equal to 120 MPa and an equivalent loss factor of 0.75.

According to yet another feature of the invention, the strip is applied on at least one of the elements by an extrusion process, and or encapsulation and / or transfer from a molding and / or injection molding.

Finally, the strip may have a uniform section or not all or part of its length. The profile is inserted between two elements that can be metal-metal type glass to glass, metal plastic, glass-plastic or plastic-plastic.

For example, the strip may be interposed between a glass substrate and a metal member so as to be used to secure the substrate to the metal element. Particularly in its use in a motor vehicle glazing when disposed between the glazing and the bodywork, the section generates for glazing improved acoustic damping performance, especially with respect to the original structure-borne noise, c ' i.e. for low frequencies, of the order of 50 to 300 Hz. the inventors have also found that the same performance can be achieved for the 300 to 1000 Hz noise, said dirty noises, in particular for laminated windows.

Finally, the inventors have demonstrated that this section can also perform an acoustic damping wind noise, that is to say to frequencies above 1,000 Hz, however, when the glazing is particularly monolithic, that is to -dire consists of a single glass sheet.

The strip of the invention can therefore be used for a glazing, particularly a motor vehicle. The glazing may be comprised of a monolithic glass, a laminated glass or of a laminated glass called "acoustic", that is to say incorporating a plastic film with acoustic properties.

Finally, the invention defines a method for assessing the acoustic damping properties of a profile to be inserted between two elements consisting of at least a damping material i, characterized in that it is to assess the stiffness per unit length actual equivalent K '_eq the section and the equivalent loss factor tanδ_eq, The profile having acoustic damping properties when the equivalent real stiffness per unit length is at least equal to 25 MPa and the equivalent loss factor is at least equal to 0.25.

The evaluation of the actual equivalent linear stiffness K '_eq the section and the equivalent loss factor tanδ_Θq is carried out using an as explained above viscoanalyzer.

Other advantages and features of the invention appear from the following description with reference to the accompanying drawings in which: • 1a to 1c are views in partial section of two elements joined by means of a profile according to three variants of a first embodiment of the strip of the invention;

• Figures 2a to 2d illustrate partial sectional views of two elements joined by means of a profile according to variants of a second embodiment of the profile, the profile being formed by a stack of materials;

• Figures 3a to 3d illustrate partial sectional views of two elements joined by means of a profile according to variants of a second embodiment of the profile, the profile consisting of a juxtaposition of materials;

• Figures 4a to 4d illustrate partial sectional views of two elements joined by means of a profile according to variants of a second embodiment of the profile, the profile consisting of a combination of stack (s) and juxtaposition (s) of material;

• Figure 5 shows schematically the steps to the combination of two elements by means of the profile according to the first embodiment;

• Figure 6 shows a variant form of a profile view of a profile integral with one of the elements to be associated;

• 7 schematically shows the steps for the combination of two elements by means of the profile according to the second embodiment;

• Figures 8a to 8f illustrate sectional profile or other profile shape variants integral with one of the elements to be associated;

• 9 schematically shows the steps for the combination of two elements by means of the profile according to the variant of Figure 8a;

• Figures 10a and 10b illustrate two coextrusion of two variants of damping materials made integral with one of the elements to be associated;

• Figures 11a and 11b schematically show the steps for the combination of two elements by means of the section respectively according to two variants of the type of Figure 4d;

• Figure 12 shows the modal damping for the first bending mode obtained on a glass substrate provided with the profile, according to values ​​of the real linear equivalent stiffness K '_eq and the equivalent loss factor tanδ_eq; • Figure 13 shows curves of the noise measured by the engine speed of a motor vehicle for three types of profile.

These figures are schematic and do not respect the relative proportions of the various sizes, thicknesses and widths in particular, between the various elements of the invention, in order to facilitate reading.

1a is a fragmentary sectional view of a glazing 1 associated with a supporting element 2 such as a motor vehicle body. The glazing consisting of at least a glass substrate, is fixed to the bodywork by means of a strip 3 to an acoustic damping property.

Therefore, the section 3 associated and inserted between two elements 1 and 2 that are taken here as an example, respectively the body and the glazing, plays in addition to its role of damping vibrations according to the invention, the role of the two elements fixing device ensuring a sealing function to protect the vehicle interior against environmental stress such as dust, moisture, water. However, in another application, the section might only be inserted between the two elements only to fulfill its role without amortization play a role in securing the two elements. For example, the profile can be fixed to a first member such as a door frame of a room inside a building and is associated with a second element such as the door when it is closed; the profile, in-constrained surfaces of the door and the frame sufficient to absorb the excitation energy of the frame, allows to reduce the acoustic radiation within the volume enclosed by said door.

We will see in the following description the constitution of the section 3. The profile can be enhanced with functional forms that are not specifically as acoustic sealing lips or aesthetics.

The acoustic damping property of the profile is defined by parameters that are the equivalent linear stiffness and loss factor.

The profile can be composed of a single material or a plurality of materials, and in the latter case, account must be taken of the stiffness per unit length of each material. That is why we speak of equivalent linear stiffness, denoted K *_eq which corresponds to the equivalent stiffness for the entire profile and said linear because it is reduced to 1 m profile. As known, the equivalent linear stiffness K^*_eq is a complex number is writing K *_eq = K_eq K + j "_eq with the real part K '_eq, Called in the description of the real equivalent stiffness per unit length, and the imaginary part

K "_Θq which corresponds to power dissipation, that is to say the conversion of energy of deformation of the profile into heat energy throughout the profile.

K *_eq can be expressed by the formula, because the profile can include multiple materials:

<img id="imgf000012_0001" he="8" wi="44" file="imgf000012_0001.tif" img-format="tif" img-content="drawing" orientation="portrait" inline="no" />

K *: complex linear stiffness of each material constituting the i section, α = -1 for i a stack of several materials arranged in series, that is to say according to a so-called stack arrangement in the following description, α = 1 for a juxtaposition of several materials i in parallel, that is to say according to a known arrangement in juxtaposition in the following description.

For a combination of a stack and a juxtaposition, it will calculate the equivalent linear stiffness of the stack and that the juxtaposition, and the section will be reduced to a single stack or a single juxtaposition such that α = -1 or respectively α = 1.

This gives for example two series of materials:

1 / - 1 / + 1 / or 1 / - 1 / + 1 /

/ K^*eq ^~ / K^*l / K^*2 / (+ K'eq jK "eq) ^~ / (K \ + jK'ï) ⁺ / (Kl + jK "2) where: _{j ûn}_ [K^,l²K2 + K'l²K2 + KLK2²KLK + ² / _βt^{eq ~} / [(Kl + K2)²+ (K'l + K2.)²] ^eι

_V,, _ [K1²K + K'1²K + K^,1K2²+ K'IK2²} /

^{Eq Λ ~} / [(K1 + K2)²+ (K'1 + K2.)²] For two materials in parallel include: K'eq = K'1_eq + K'2_eq and K "_eq K = "1_eq + K "2_eq

Examples of provisions to stack and / or juxtaposition of a number i of materials will be described below with reference to Figures 1a to 1c, 2a to 2d, 3a to 3d and 4a to 4d. Furthermore, the stiffness per unit length depends on the rigidity of the material forming the section but also the dimensional sizes of the section of each material constituting the profiled section.

Also, the linear stiffness K * j for a given material in equation (1) is written, being referred to a rail length of 1 m and a rectangular section of width and thickness e ,, and based on the principle that the profile is stressed in tension uniform compression across the width (shear is not considered):

K^*i = i * e ^ X (2)

with E * ι the complex Young modulus of the material constituting the i profile. By breaking into real and imaginary parts, equation (2) writes:

K * ι = K '+ YKi "= E |' x ^ - + jE-r e x ^_t e_t E'j with the real part of the complex Young's modulus and named in the module description of Young, and E "i, the imaginary part of the complex Young's modulus.

Recall that according to the invention, one of the parameters characterizing the acoustic properties of the profile is the equivalent real linear stiffness K '_eq, That is to say the real part of the complex number K *_eq. The estimate of K '_eq can be achieved by calculation as it has been explained as estimated by measuring the Young's modulus of each material E'j, measurement made with a viscosity analyzer. The estimate of K '_eq by a measurement using a viscosity analyzer may be made to confirm the calculations.

However, these calculations are suitable when the shape of the profile is rectangular. For any other form, perform in fact a measure of that greatness with the viscoanalyser.

For the choice of materials used to form the profile when these materials are not simple rectangular shape, it will be made approximate calculations by establishing an approximation of the real section of each material to a rectangular section for which the profile feeling the tension-compression efforts. If the calculations are in favor of choice of materials because the criteria claimed that we will outline below, these calculations will be validated by measurement using the viscoanalyser. According to the invention, so that the section 3 performs its acoustic damping function, it must have a real equivalent stiffness per unit length K '_eq at least equal to 25 MPa. Preferably the equivalent real linear stiffness K '_eq is between 30 and 250 MPa.

Moreover, as we have written above, operates in the acoustic damping performance of the profile the equivalent loss factor (or tangent of the equivalent loss angle) tanδ_eq which is defined by the relationship:

tanδeq (3) <img id="imgf000014_0001" he="12" wi="13" file="imgf000014_0001.tif" img-format="tif" img-content="drawing" orientation="portrait" inline="no" /> wherein K '_eq is the equivalent real linear stiffness (real part of K^*_eq) For all of the profile and K "_eq is the dissipation power (imaginary part of K^*_eq).

Similar to the estimation of the real equivalent stiffness per unit length, the loss factor will be estimated by calculation using the equation (3), equations (1) and (2) for calculating K '_eq and K "E_q&gt; K '_eq and K "_eq being estimated by calculation using the measurement by the viscoanalyzer of the real part and the imaginary part respectively of the complex Young modulus of each material constituting the profiled section. The measurement of the entire profile thanks to viscoanalyzer used to validate the calculations, especially when it comes to choose any non-rectangular section of material.

In all cases, to ensure that the profile meets the criteria claimed that we will outline below for this loss factor, a measure of viscoanalyser the equivalent real linear stiffness and calculation of the loss factor will be performed.

According to the invention, the strip 3 has an acoustic damping property when the equivalent loss factor tanδ_eq of the profile is at least equal to 0.25.

The equivalent loss factor and the equivalent real linear stiffness depend not only on the chemical nature of the profile of the materials but also the geometry given to the section of the profile. Also, when a section meets the criteria claimed according to the invention of the equivalent loss factor and stiffness equivalent linear, it is possible to optimize these parameters by changing to further increase the acoustic performance. Changing these parameters is achieved by changing the dimensions of the profile section. For example, if the profile is made of a single material and has a rectangular section, is then increased its actual linear equivalent stiffness by reducing the thickness e of the profile and increasing its width L.

The profile 3 may consist structurally of different ways.

According to a first embodiment illustrated in Figures 1a to 1c, the section 3 is constituted by at least one damping material 4 which provides acoustic damping function and in addition, the securing function of the two elements and optionally the function sealing according to the type of use for which the profile is intended. In the example of glazing for a motor vehicle, the profile preferably provides also the sealing function. This profiled configuration including one or more damping materials that also realize a bonding function for connection of the two elements will be hereinafter referred to as the monolithic profile description.

According to this first embodiment, a first variant (Figure 1a) is to achieve the profile of a single material that meets the criteria set for the equivalent loss factor and the equivalent real linear stiffness and has the bonding properties with the two elements 1 and 2, and if necessary sealing properties.

A second variant of the first embodiment consists in making the strip 3 in two damping materials 4a and 4b which meet the criteria of the invention. These materials, while being more or less damping with respect to each other, generate by their association an equivalent real linear stiffness and an equivalent loss factor meeting the damping criteria. They are arranged in layers one above the other (Figure 1b), or are juxtaposed one beside the other (Figures 1c) and possibly separated by an air gap (not shown). Materials both have bonding properties with at least one of the two elements to which they are associated.

It is also possible to envisage more than two damping materials taken in combination according to a juxtaposition and / or stack (not shown).

Examples of materials that can be used for a monolithic profile will be cited in the following description. According to a second embodiment illustrated in Figures 2a to 2d, 3a to 3d and 4a to 4d the section 3 is constituted by at least one shock absorbing material 4 and a bonding material 5 nondamping. The material 4 provides acoustic damping function and is made integral with at least one of the two elements

1 and 2 to be associated, while the bonding material 5 provides the fastening function of the two elements 1 and 2 being made integral with at least one of the two elements 1 and 2. The materials 4 and 5 are chemically compatible to ensure if necessary, depending on the variant, their mutual adhesion. The materials 4 and 5 may have sealing properties with use of the profile.

In this second embodiment, the bonding material 5 nondamping serves only the connection of the two elements 1 and 2 and also has sealing properties. He has no acoustic damping property alone. However, it is necessary to give it thickness and width well suited because it has a Young's modulus E i 'and a tanδ loss factor influencing the equivalent real stiffness per unit length and the equivalent loss factor of all of the profile 3 and therefore the acoustic damping property of the entirety of the strip 3.

According to this second embodiment, the arrangement of materials between the two components can vary.

It may be of the stack (2a to 2d), that is to say that the materials are arranged in layers one above the other, each of the materials at the ends of the stack being secured to one of the two elements 1 and 2 to be combined.

It can be of juxtaposition type (3a to 3d), that is to say that the materials are joined or not to each other, each material having two opposing surfaces made integral with the two elements 1 and respectively

2 to associate.

A third type of variation of the second embodiment is a provision that a combination of a stack and a juxtaposition (4a to 4d), at least one or two materials partly constituting this combination being made integral elements of both 1 and 2 associate.

Figures 2a-2d illustrate how different layout variations stack. The stack of Figures 2a and 2b consists of a material 4 to an acoustic damping property and a non-absorbing material 5 of adhesion of the section one of the elements. In Figure 2a the material 4 is integral with the element 1, the glass substrate, and the bonding material 5 adheres by one of its faces 50 and the damping material 4 is adhered by its opposite face 51 to the element 2 , the bodywork ; whereas 2b 4 and 5 materials are respectively integral with the body and the glass substrate. The material strata are of identical width L1, and each has a thickness e1, e2 which is adapted according to the nature of the material and therefore according to the loss factor of each material so as to maximize the effective linear stiffness equivalent and / or factor equivalent loss of the profile.

Figures 2c and 2d correspond to a stack of three materials, two materials 40 and 41 constitute the damping material 4 and the third material is the bonding material 5. The material strata are of identical width to Figure 2c, and width different to Figure 2d, the thickness of each stratum being studied to optimize the equivalent real stiffness per unit length and / or the equivalent loss factor of the profile 3.

Figures 3a to 3d illustrate different juxtaposition available variants.

In Figure 3a, the juxtaposition along two materials is to append a damping material 4 with a bonding material 5, both of the same thickness and made integral by two of their opposite faces, 50 and 51 for the bonding material, with the two elements 1 and 2 are that the glass substrate and the body. Their widths L1 and L2 are defined to optimize the calculation of the equivalent real stiffness per unit length and / or the equivalent loss factor.

3b shows the Figure 3a with the inversion of the materials 4 and 5, the bonding material nondamping being disposed on the side of the vehicle cabin.

3c reproduces Figure 3a except that the materials are not contiguous but separated by an air gap 6.

Figure 3d is representative of a juxtaposition of three adjoining material, a non-damping material 5 bonding sandwiched between two damping materials 42 and 43 forming the damping material 4. Materials 42 and 43 may or may not be distinct. Depending on the thickness given to different materials placed along a juxtaposition, the width of each of the damping materials 4 (therefore also 42 and 43) and adhesive 5 is designed to ensure the equivalent real stiffness per unit length and the equivalent loss factor of all materials, so the section 3, adequate to the desired acoustic damping.

Figures 4a to 4d are a combination of provisions stack and juxtaposition, at least the bonding material being made integral with two opposite faces to the elements 1 and 2 to be combined.

4a is a juxtaposition of the bonding material 5 and the damping material 4, the latter being formed of a stack of materials 44 and 45 separate and more or less damping with respect to the other.

4b reproduces Figure 4a except that the bonding materials 5 and damping 4 (44, 45) are separated by an air gap 6.

Figure 4c illustrates a juxtaposition of several contiguous materials, the bonding material 5 is sandwiched between the damping materials 4 which are constituted by two stacks of at least two distinct materials 46, 47, the stacks may be different from the other.

Figure 4d illustrates a contiguous juxtaposition of three materials, the bonding material 5 and two different damping materials 4 or not. The bonding material 5 is sandwiched between the two damping materials 4 and has one of its faces 51 which extends along the width L of the section and is secured to one of the elements 2 so that the materials 4 are stacked in a thickness e1 and e2 to a thickness of the material 5. the opposite face 50 of the bonding material 5 is secured to the other element 1 and has a width L2, while materials 4 are disposed against said member 1 according to L1 and L3 widths.

In the second embodiment to which the nondamping 5 bonding material is separate from the damping material 4, the bonding material 5 which is also used for the sealing function is for example a polyurethane sealant such as Gurit Betaseal 1720 marketed by Dow Automotive company. It provides the example for the sealing of the glazing to the body and sealing against gases, dust, water vapor and liquid water or solvents. The inventors have determined several plastics that can provide the damping properties required for the damping material 4 of the first embodiment or the second embodiment according to the referenced declined from 40 to 47 variants.

Exemplary are:

- Polychloride vinyl plasticized or not,

- Thermoplastic elastomers,

- Mono or bicomponent polyurethanes, modified or not by an elastomer such as polyolefins, EPDM (ethylene-propylene-diene), or rubber, in particular butyl rubber, or nitrile, or styrene-butadiene,

- Copolymers of alkyl acrylates or polyalkyl,

- Epoxide resins.

The compositions mentioned above may additionally contain organic or inorganic fillers such as talc, silica, calcium carbonate, kaolin, alumina, molecular sieve, carbon black, graphite, fumed silica, metal fillers such as zinc oxide, titanium oxide, alumina or magnetite. The load factor can vary between 0 and 50% by weight of the final composition.

On thermoplastic elastomers (TPEs), they consist of mixtures of polymers or copolymers sequences manifesting a thermoplastic phase and an elastomeric phase optionally chemically bonded together in the case of copolymer.

Regarding polyurethanes, it can be thermoplastic urethanes (TPU) which exist for example in the form of a non-reactive polymer, obtained from several polyol sources including at least one form is a sequence having thermoplastic properties and at least a another form is a sequence with elastic properties.

It is also possible to choose a polyurethane material with a wide variety of reactive compositions, the mono- or bi- component types. Examples include such one-component compositions based on polyester backbone polyurethane prepolymer, polyether, polycaprolactone, polyolefin, polysiloxane. The advantage of a siloxane-terminated prepolymer that is moisture curing without foaming. These polyurethane compositions may be modified by an elastomer such nitrile rubber, or SBR, or butyl, or a thermoplastic elastomer or a polymer having flexibility non-crosslinkable, such as polyolefins or plasticized PVC.

Among the single-component polyurethane prepolymer compositions which crosslink with moisture and / or temperature, they are obtained by reaction between polyols and polymeric or nonpolymeric diisocyanates.

Polyols compositions may be polyethylene-type polyether polyol, propylene oxide, polytetramethylene oxide, polybutadienepolyol ployol or polycarbonate, the polyester polyols, amorphous or crystalline, aromatic or aliphatic, based on fatty acid dimers, aromatic or aliphatic diacids, of castor oil, type 1 chain extenders, 3 or 1, 4 butane diol, diisopropyl glycol, 2,2-dimethyl-1, 3-propanediol, hexanediol, carbitol. The molecular weight of these polyols will be defined by their hydroxyl number (OHN) defined in ASTM E 222-94 as the number of milligrams of potassium hydroxide equivalent to the hydroxyl content of 1 gram of polyol. NOH the range used is between 5 and 1500. The functionality of these polyols is comprised between 2 and 6.

The isocyanates may be aromatic or aliphatic, including of diphenylmethane diisocyanates (MDI), of toluènediisocyantes (TDI), of isophoronediisocyanates (IPDI), the hexane diisocyanate (HDI). The nature of the isocyanate is also defined by their NCO percentage, according to ASTM D 5155-96, is defined as the proportion by weight of isocyanate functional (NCO) groups in the product. Product functionality is between 2 and 2.7

The catalysts required for the reaction between the polyols and isocyanates may be tin catalysts such as dibutyl tin dilauryl (DBTDL), the étain.On octoate may also be used bismuth catalysts, or catalysts based on morpholines such as dimorpholinodiethylether (DMDEE).

To avoid foaming of the chosen prepolymer, may be added anti-foam additive which is a compound based on bis-oxazolidines. Finally, various plasticizers may also be advantageously added to the prepolymer selected. In general, the application of the section 3 between the elements 1 and 2 is done as follows (Figure 5): the section 3 is deposited on the element 1 by an application method that we develop in the subsequent description. Depending on the chemical nature of the free surface of the profile to be associated with the element 2, this surface is either stuck conventional manner since they have adhesive properties at room temperature, or this free surface is activated with a 7 energy source of infrared type ultraviolet, high-frequency, microwave or induction, and when the surface reaches a suitable temperature profile associated with the first element 1, as the substrate is applied by pressure against the second element 2, as the body, for fastening. The amount of energy and the thickness of the or activated materials are calibrated for the width and the desired final thickness between the two elements 1 and 2.

The application of section 3 against the first element can be done in different ways. The technique used will depend on the nature of the material and arrangement stacking and / or juxtaposition of materials.

At least four calibrated profile of the deposition techniques may be used alone or in combination: extrusion, molding (encapsulation) and the transfer from a molding. As for the transfer process, reference to details in the French patent application FR 01/15039.

The extrusion technique guarantees a constant geometry to the profile. Advantageously, the shape given to the section may facilitate attachment with the item to which it is associated to ensure the desired geometry. The damping materials used must have viscosities between 100 and 500 Pas at 80 ° C, the freezing material below 50 ° C. The materials will therefore have a greenstrength and a sufficient thixotropy to maintain their geometry after extrusion. They will preferably single component type and ensure a good bond with the first element associated with it, such as the glass substrate in the example.

According to the second technique, the section can be overmolded on one of the elements to advantageously give any desired shape and thus optimize the acoustic performance guaranteeing section dimensions at any point of the glass because it may be necessary that the width and thickness profile is not uniform over the entire periphery of the element to which it is associated for the purpose of acoustic performance (Figure 6). The viscosity of the materials used must not exceed a certain limit and taking a two-component product will be fast.

According to the third technique, the profile can also be molded and transferred to one of the elements to retain the advantages of the molding and reduce the costs of production of molds. This technique combines the advantages of extrusion and molding because it allows to create multiple layers of various forms of material as shown in Figure 2d. As for extrusion, a greenstrength and a minimum viscosity materials are required for moisture-crosslinking one-component materials. The setting time may be rapid if one component type and curing systems with temperature are employed. Two-component systems are for their quick setting.

Finally, a technical injection molding is also possible. This is to place the element at which to associate the material into a mold having a cavity corresponding to the shapes of the profile that is to be achieved and is injected into the mold the molding material consisting of the material damping melt.

Examples of techniques used, there are following the association of two elements according to the first embodiment of the profile, that is to say as a monolithic section, and according to the second embodiment, namely when the profile comprises at least two materials 4 and 5 corresponding respectively to the damping material and nondamping bonding material.

For a monolithic strip 3, the application against the glass substrate 1 is made by a choice of four techniques.

For extrusion against the element 1 thus with a single damping material 4, which also ensures the fastening function with the element, the inventors have developed a material A for the criteria of the invention and the surface is activated for be secured to the element 2. It is a crosslinking component polyurethane moisture having a single glass transition temperature Tg and comprising: - At least one polyester polyol of functionality equal to two (preferably between 80 and 200 g), having a iOH index between 5 and 10, a lower glass transition temperature T or equal to -50 ° C and a softening point of 50 and 80 ° C,

- At least one polyester polyol of functionality equal to two (preferably between 120g and 220g) having an iOH index between 50 and 100, a lower glass transition temperature T or equal to -50 ° C,

- At least one isocyanate functionality of between 2.1 and 2.7 of the type diphenylmethane (MDI) and having a percentage of NCO of 11 to 33% (preferably between 180 and 220g)

- At least one catalyst (preferably between 0.5 and 3 g),

- Possibly a molecular sieve load (preferably between 20 and 60g)

- Optionally at least one type of load chalk, kaolin, talc, alumina, carbon black, graphite or (preferably between 5 and 60g).

The percentage of NCO of this polyurethane prepolymer A is between 0.5 and 2%.

For such a material A used to form a profile of equal rectangular cross-section the reference section Lxe = 15mm x 3mm, the value of Young's modulus E 'measured at 120 Hz and at an ambient temperature of 20 ° C is 80 MPa. The equivalent loss factor which consists of the loss factor of one material is equal to 0.3 and the equivalent real linear stiffness is 400 MPa.

For the purposes of a profile 3 consisting of at least two materials 4 and 5 according to the second embodiment, it is possible to coextrude the two materials on the glass substrate 1. After this first step, the consolidation is effected by heating the free surface of the profile and applying it against the body (7), or by applying directly against the free surface of the body depending on the nature of the materials.

Alternatively, it is possible to mold or transfer after molding on the glass substrate the damping material 4 by giving it the desired shape (8a to 8f). 5 the bonding material is then extrusion coated on the free surface of the damping material 4 (Figure 9). One can thus give the damping material with a specific profile for example ledges 48 (8a, 8b, 8c) which are used to guide the bonding material and to define the thickness and / or width of said bonding material when filed, or such with central projections 49 (Figures 8d, 8e, 8f ) used to calibrate the thickness of the bonding material. For interlocking, the surface of the bonding material 5 deposited on the damping material 4 is heated if necessary and the section is placed against the body (Figure 9).

In the case where the strip 3 is made of a bonding material 5 and two damping materials stack type 40 and 41, the two damping materials may be coextruded on the glass substrate 1 as illustrated by the two variants of FIGS 10a and 10b. The deposition of the bonding material 5 on the surface of the free smolder and opposite the substrate and the bonding material are then carried out as illustrated in Figure 9.

Figures 11a and 11b show the securing steps of the element 1 to the element 2 by means of two respective variants of a type of profile that illustrated in Figure 4d. The material 4 is first molded and transferred to element 1. It shows a particular geometry, in particular is separated into two parts 400 and 401 so as to form a reception channel 402 for receiving the adhesive material 5 when the fastening. The bonding material 5 present in the final two opposite faces integral respectively of the two elements 1 and 2.

An example of a profile comprising at least a damping material 4 and a bonding material 5, is made of a material B as damping material 4 and a structural sealant 5 such as nondamping polyurethane sealant. Each of the materials has a rectangular section of 15 mm wide and 3 mm thick, which represents a total section equal to the reference section to the section of 15 mm wide and 6 mm thick.

The composition of B material developed by the inventors is of type crosslinking polyurethane one-component moisture, having a single glass transition temperature, comprising:

- At least one polyester polyol of functionality equal to two (preferably between 350 and 450 g), having an OH number between 20 and 40, a Tg transition temperature between -40 and -20 ° C,

- At least a functionality equal to two polyester polyol having an OH number between 30 and 90 (preferably between 35 and 250 g), a Transition temperature Tg between 0 and 30 ° C and a softening point between 50 and 70 ° C;

- At least one isocyanate functionality of between 2.1 and 2.7 of the type diphenylmethane (MDI) and a percentage of NCO of 11 to 33% (preferably between 150 and 230 g);

- At least one catalyst (preferably between 0.5 and 3 g);

- Possibly a molecular sieve load (preferably 20 to 80 g); optionally at least one type of filler chalk, kaolin, talc, alumina, carbon black, or graphite (preferably between 5 and 60 g).

The percentage of NCO of this polyurethane prepolymer B is between 0.5 and 2%.

The values ​​of Young's modulus and the loss factor for the damping material B are as follows at an ambient temperature of 20 ° C: E '= 35 MPa and tanδ = 1, 4.

The values ​​of the Young's modulus and loss factor for nondamping 5 polyurethane mastic adhesive material are the following 120Hz and an ambient temperature of 20 ° C: E = 21 MPa and tanδ = 0.2.

The values ​​of the equivalent real stiffness per unit length and the equivalent loss factor are respectively equal to 70 MPa and 0.95.

The inventors also developed another damping material C and having adhesive properties, in particular with a low temperature bond strength (between -60 and -10 ° C). This material, unlike the materials A and B have two glass transition temperatures. This is a polyurethane prepolymer comprising:

- At least one polyether polyol of functionality equal to two, having an iOH index between 25 and 35, a Tg transition temperature below -50 ° C, of ​​molecular weight between 3500 and 4500;

- At least one polyether polyol of functionality between 2.3 and 4, having a iOH index between 25 and 800, a glass transition temperature T less than -50 ° C;

- At least one polyester polyol of functionality equal to two, iOH having a value between 20 and 40, a Tg transition temperature between -40 and -20 ° C; - At least a functionality equal to two polyester polyol having a iOH index between 30 and 90, a Tg transition temperature between 0 and 30 ° C and a softening point between 50 and 70 ° C;

- At least one isocyanate functionality of between 2.1 and 2.7 of the type diphenylmethane (MDI) and a percentage of NCO of 11 to 33%;

- At least one catalyst;

- Possibly a molecular sieve load;

- Possibly a type of filler chalk, kaolin, talc, alumina, carbon black or graphite.

The percentage of NCO of this polyurethane prepolymer is between 0.5 and 2%.

In particular, can be described as a mixture according to the composition C above, the NCO% is between 1, 8 and 2.2% and comprising: between 180 and 220 g of a polyether polyol of functionality equal to two, having iOH a number between 25 and 35, a Tg transition temperature below -50 ° C, of ​​molecular weight between 3500 and 4500 between 75 and 115 g of MDI type isocyanate, a% NCO equal to

11, 9% between 5 and 30 g of carbon black; between 0.5 and 3 g of catalyst between 10 and 30 g of fumed silica of 135 to 180 g of a polyester polyol A, and amorphous liquid iOH index between 27 and 34, of molecular weight equal to

3500, a functionality equal to two and temperature Tg transition equal to -30 ° C; between 35 and 85g of a liquid polyol polyester B and amorphous iOH index between 27 and 34, of molecular weight equal to 3500, of functionality equal to two, and Tg transition temperature respectively equal to + 20 ° C; between 55 and 110 g of an MDI isocyanate, NCO% equals

11, 9%, between 20 and 80 g of molecular sieve. C for such a material used to form a profile of equal rectangular cross-section the reference section Lxe = 15mmx3mm, the value of Young's modulus E 'measured at 120 Hz and 20 ° C is 22 MPa. The equivalent loss factor which is made of the only material loss factor is tanδ = 0.75 and the equivalent real linear stiffness is 120 MPa.

This material C having two glass transition temperatures can also be used at low temperatures because it presents not only an acoustic damping property but also in adhesion strength. Indeed, at -40 ° C, the loss factor is 0.38 and the value of Young's modulus is 900 MPa, the inventors attributed the bonding strength property, that is to say when there is no risk of adhesive failure with the element which is associated with the material, as the rigidity of the material E is less than 2000 MPa for a frequency between 50 and 500 Hz.

The inventors have managed to select damping material compositions that meet the criteria of the equivalent real linear stiffness and loss factor equivalent statements by the invention. To check whether or materials to be used in a profile for an acoustic damping property and the shape of the section or of these materials meet the criteria provided by the invention, the inventors have developed an evaluation method.

It should when considering rectangular sections of materials:

- To measure the Young's modulus Ej 'and the dissipation rate E "of the material to be used for the profile,

- Assessing the equivalent real linear stiffness K '_eq and tanδ equivalent loss factor_eq from equations (1), (2) and (3) mentioned above,

- Finally to compare these values ​​of K '_eq and tanδ_eq of the profile with the reference values, respectively 25 MPa and 0.25, above which the acoustic performance is achieved.

We can optimize the values ​​of these parameters and thus achieve better noise attenuation by varying the thicknesses and widths of materials.

The Young's modulus values ​​Ej 'and dissipation power E "of each material were measured by using a visco-analyzer such as that marketed under the brand under certain conditions METRAVIB measures set out below:

- Sinusoidal stress,

- Test for the material consists of a cuboid dimensions of rectangle as they fall within the ranges defined by the manufacturer of viscoanalyser, for example:

* Thickness e = 3 mm

* Width L = 5mm

* Height = 10mm

- Dynamic range: ± 5.10^"6m around the rest position,

- Frequency range: 5 to 400 Hz

- Temperature range of - 60 to + 60 ° C. ι

The viscoanalyser allows you to submit a sample of material to deformation stresses under specific conditions of temperature and frequency, and thus to obtain and process all rheological parameters characterizing the material.

The exploitation of raw data measurements of force, displacement and. phase shift as a function of frequency, at different temperatures, allows in particular the establishment of the Young Eι module and dissipation power E "of the material.

To validate the method of evaluation described above research materials and sizes, and in all cases to ensure that a profile has the features claimed by the invention, it will make using the viscoanalyser direct measurements of the real equivalent stiffness and dissipation equivalent to a section profile of sample identical to that of the section and length L. It will then be necessary to perform the following calculations:

- Ratio of the measured real equivalent stiffness and length L to obtain the real equivalent stiffness per unit length K '_eq the profile: K '_eq = K '_eq/ L;

- Ratio of the equivalent measured power dissipation and measured real equivalent stiffness for the equivalent loss factor tanδe_q the profile: ^ eq Finally, the inventors have chosen to illustrate the acoustic performance obtained by the profile 3 according to the actual linear equivalent stiffness K '_eq and the equivalent loss factor tanδ_eq according to the graph in Figure 12. The x-axis are given the values ​​of the equivalent loss factor and the y are given the values ​​of the equivalent real linear stiffness. Based on these values, the graph indicates the modal damping on the first mode of bending measured for a glass substrate (800 mm by 500 mm and thickness 4 mm) glued onto a marble by means of the profile arranged at the periphery and on one side of the substrate, the equivalent loss factor tanδ_eq which may be between 0.15 and 1, and the equivalent real linear stiffness not exceeding 400 MPa. Note that the values ​​of the gains for data tanδ_eq= L can be extrapolated tanδ_eq&gt; L for the same values ​​of the equivalent stiffness.

The modal damping is expressed on a scale from 0 to 30%. Plus depreciation, the greater the acoustic gain in dB is important.

The modal damping on the first bending mode is defined as follows. The modal damping is deduced from measurements of mechanical impedance Z (module the frequency response function giving normal speed vibratory glass substrate at a point depending on the time effort injected at the same point in the normal management audit substrate) made using an impact hammer and an accelerometer at the center of the substrate.

The frequency of the first mode of bending corresponds to the frequency less than 120 Hz for which the mechanical impedance is maximum. It is denoted by f1. The value of the mechanical impedance at the frequency f1 is denoted Zmax.

The bandwidth at half height corresponds to the width of the range of frequencies around f 1 for which Z&gt; ZmaxΛ / 2. It is denoted by Df.

The modal damping of the first mode of bending is the ratio Df / f 1.

Depending on the values, the graph shows that the modal damping and therefore the acoustic performance (gain in dB) are variable for the same loss factor and different equivalent stiffness, or vice versa.

Thus it is for example possible to obtain a modal damping of almost 30% for an equivalent real linear stiffness of 100 MPa and a loss factor between 0.5 and 1, while amortization does not exceed 5% if the loss factor of only 0.3 for the same real linear stiffness of 100

MPa.

It is also seen as a loss factor of 0.8, for example, optimal equivalent real stiffness per unit length will be around 100 MPa and that the increase in the equivalent real linear stiffness will only decrease the modal damping obtainable.

This graph is used to indicate that the use of the material A as explained above for a monolithic section and having a real linear stiffness equivalent equal to 400 MPa and an equivalent loss factor of 0.3 produces a modal damping between 5 and 10%.

The use of the material B associated with the nondamping polyurethane sealant for the profile given by way of example above in the second embodiment which has a real linear stiffness equivalent equal to 70 MPa and an equivalent loss factor 0 95, generates a modal damping greater than

20%.

Furthermore, it is shown in Figure 13 three comparative curves of the noise measured by the engine speed within a motor vehicle for three types of profile.

The curve C1 corresponds to a standard laminated glazing with a standard profile consisting of polyurethane mastic nondamping in a reference section of 9 mm by 6 mm.

Curve C2 corresponds to a standard glazing equipped with a monolithic profile according to the invention consisting of damping material 4 of composition A at a reference section of 15 mm by 3 mm.

The curve C3 corresponds to a standard glazing equipped with a profiled according to the invention consisting of damping material 4 of composition B and the bonding material 5 in nondamping polyurethane mastic with a reference section of 15 mm by 6 mm.

Means standard laminated glazing, glazing comprising two thick glass sheets 2.1 mm and a polyvinyl butyral interlayer film of 0.76 mm thickness.

We recall the following table the values ​​of the equivalent real stiffness per unit length and the equivalent loss factor for the three types of profile.

<img id="imgf000030_0001" he="10" wi="152" file="imgf000030_0001.tif" img-format="tif" img-content="table" orientation="portrait" inline="no" />

<img id="imgf000031_0001" he="54" wi="152" file="imgf000031_0001.tif" img-format="tif" img-content="table" orientation="portrait" inline="yes" />

The curves in Figure 13 show improved noise reduction achieved through the profile of the invention. In this figure, the noise in dB is a function of engine speed in rev / min the vehicle. The measured noise generated here is in the range of 50-160 Hz frequencies, frequencies corresponding to the original structure-borne noise and corresponding to an engine speed of 1,500 to 5,000 rev / min vis-à-vis the given type of motor vehicle taken by way of example.

Note that the measurements are independent of the area of ​​glazing.

The results show that the frequency of 110 Hz which corresponds to 3400 rev / min and at a regular diet highway, noise measured for the glazing of the curve C1 is much greater than the noise measured for the glazing of the curve C2 and further compared with that of curve C3, a noise damping of 4 dB and 13 dB, respectively, is thus obtained through the strip of the invention according to one of two alternatives, respectively, as has been seen also for According to the graph of Figure 12.

The use of the profile of the curve C2 may be preferred because it has good damping performance at 3400 turn / min, and also exhibits good performance for high speeds around 4000 rev / min, for which it is seen that the measured noise is 82 dB while noise measured for the curve C1 with a standard profile is 87dB. This is achieved because the equivalent real stiffness per unit length of this section of the invention is much greater than that of the standard profile.

The strip of the invention to an acoustic damping property has been described by way of example to be inserted between two elements 1 and 2 such as a glass substrate and a vehicle body for fixing them to each other, and thus a glass-metal combination. Other applications may be contemplated for use acoustic damping strip of the invention, for example for metal-metal combinations, glass-glass, metal-plastic, glass-plastic, plastic-plastic. plastic is understood to mean plastic materials such as epoxy, polyester, polycarbonate, polymethylmethacrylate (PMMA), acrylonitrile butadiene styrene or composite materials plastic-based, such as polypropylene (PP) and reinforcing fibers such as glass fibers or wood fibers.

For a metal-metal association, it is for example of metal parts bonded to the body of a vehicle. Thus, the mechanical elements for doors and windows that are usually attached by bolts, may instead be fixed by bonding by means of a damping strip of the invention to reduce the radiation noise inward the vehicle cabin.

To a glass-plastic combination, it is for example the attachment of a rear window of the vehicle.

To a plastic-plastic or plastic-metal combination, it is for example the bonding of various elements constituting the tailgate of a motor vehicle, or the adhesive bonding of a polyurethane foam-based roof reinforced with glass fibers on the metal vehicle body.