Acoustic attenuation element with improved stacking performance - Patents.com

Abstract

The present invention is directed to a vibration and noise damping element (1) comprising a damping layer (2) having a first surface (3) and a second surface (3') and an adhesive layer (4) covering at least a portion of the first surface (3) of the damping layer (2). The damping layer (2) is made of a damping layer material having a viscosity at 60°C of 30,000 to 500,000 Pa·s, which contains at least one rubber component Ru, and the adhesive layer (4) is made of an adhesive layer material having a viscosity at 60°C of 50,000 to 300,000 Pa·s, which contains at least one rubber component Ru. The ratio (d1 / d2) of the thickness d1 of the damping layer (2) to the thickness d2 of the adhesive layer (4) is 0.6 to 4.0, and the sum (d1+d2) of the thickness d1 of the damping layer (2) and the thickness d2 of the adhesive layer (4) is 0.5 to 2.5 mm. The vibration and noise damping element performs well in ball drop tests at low temperatures, has good adhesion to the substrate to which it is applied, gives good vibration and noise damping performance and ensures easy separation or removal, even after storage at temperatures between 30-50°C.

Description

[Technical field]

[0001] The present invention relates to a vibration and noise damping element for mechanical structures of manufactured articles, in particular a vibration and noise damping element suitable for damping vibrations of components and structures contained in articles of the automotive industry, domestic appliances and general industry. [Background technology]

[0002] Acoustic damping materials are widely used in the automotive, appliance, and general industries to reduce unwanted vibration, structure borne noise, and air borne noise. For example, in an automobile, it is desirable to prevent vibrations generated by motors, pumps, gears, and other dynamic force sources from transferring through the vehicle body into the passenger compartment. Structure borne noise occurs when vibrations from dynamic force sources transfer through a supporting structure, typically a frame or other hollow structure, to noise-generating surfaces, such as metal or plastic panels, which convert the mechanical vibrations into sound waves. Structure borne noise and vibration can generally be effectively reduced by applying vibration damping materials directly to the surfaces of structures and components where the vibrational disturbances are generated, such as vehicle panels, floor surfaces, and the shells of machines, washers, and dryers.

[0003] JP 09-123356 A discloses a heat-resistant anti-vibration sheet including a paperboard layer, a rubber sheet layer, and a pressure-sensitive adhesive layer, which can be bonded before painting and attached to the vehicle body in a baking process after painting.

[0004] JP 05-220883 A discloses a vibration damping sheet having three laminated layers including a high elasticity suppression layer made of aluminum foil, a medium elasticity suppression layer made of a vulcanized EPDM rubber mixture, and a low elasticity adhesive layer based on butyl rubber.

[0005] EP 3 828 226 A1 discloses an acoustic damping material comprising a binder matrix that includes a bituminous or polymeric component and a filler component that includes at least one solid, particulate cellulose-containing filler, the acoustic damping material being suitable for use in damping undesirable vibrations and noise in mechanical structures and components of manufactured articles.

[0006] Acoustic damping materials used to dampen vibrations in panels and plates are generally provided in the form of preformed single and multi-layer damping elements or as liquid compositions that are applied directly to the surface of a substrate. Damping materials designed to dampen vibrations and noise within hollow structures, such as cavities, are usually provided in the form of a cavity filler insert that includes a foamable composition and one or more attachment elements that enable the cavity filler insert to be held in a desired position within the hollow structure.

[0007] Preformed single-layer and multi-layer damping elements include a damping layer that is in direct contact with the surface of the substrate to be damped against vibrational disturbances. The damping layer is capable of dissipating the kinetic energy of the vibrating surface into thermal energy through the expansion and contraction of the material of the damping layer. Widely used materials for the damping layer include bituminous and rubber-based compositions that contain relatively high contents of particle fillers and various amounts of additives, in particular plasticizers, rheology modifiers, and desiccants. Preformed single-layer and multi-layer damping elements often include a layer of an adhesive composition, such as a pressure-sensitive adhesive (PSA) or a hot melt adhesive, allowing the damping layer to be bonded to the surface of the substrate, such as a panel or floor of an automobile. Liquid-applied damping systems are typically heat-drying, gelling, or reactive compositions that are applied in liquid form to the surface of the substrate, for example by spraying.

[0008] Acoustic damping materials used to dampen vibrations of panels and plates can also be provided in the form of constrained layer damping elements, which include a damping layer and a stiff outer layer that sandwiches and "constrains" the damping layer between the stiff outer layer and the surface of the substrate to be damped. The stiffness of the outer layer is typically ten times greater than the stiffness of the layer of damping material. Commonly used materials for the outer top layer include, for example, aluminum and fiberglass cloth. Constrained layer dampers are typically more effective at damping unwanted vibrations than single layer damping elements, but they are more expensive to manufacture.

[0009] Cavity filler inserts are used to attenuate air-borne noise inside the cavity of a hollow structural component and to prevent vibration transmission through the cavity wall. Cavity filler inserts typically consist of a damping material and at least one mounting member that allows the cavity filler insert to be held in a desired position inside the hollow structure. The damping material of the cavity filler insert is typically formulated as a foamable composition that, when activated, for example at elevated temperature, expands to form a seal with the interior surface of the cavity wall. Foamable damping materials suitable for attenuating air-borne noise inside a cavity are commonly referred to as "acoustic baffles".

[0010] Bitumen-based compositions have been widely used as acoustic damping materials in the automotive and household appliance industries because they combine low-cost raw materials with high vibration damping performance, as well as reliable and easily controllable physical properties. In the household appliance market, bitumen-based damping systems currently have almost 100% market share. Highly filled bitumen compositions have been used in particular to provide sound-proofing and sound-reducing coatings, which are applied to metal and plastic components in the assembly process of automobiles and household appliances. In a conventional procedure, a mixture of bitumen and filler is first extruded and / or calendared to form a film, and then a suitable molded part suitable for use as a damping element is prepared by punching or die cutting. The damping element is then bonded to the metal or plastic sheet to be damped. The molded part can also be further processed by heating to conform to the shape of the metal or plastic sheet.

[0011] Among the main application areas of sound damping elements are the interior of automobiles and washing machines of household appliances. In these applications, these elements are exposed to low temperature exposure during their use, especially in the case of automobiles. In the automobile industry, the quality and performance of components used in automobiles at low temperatures of approximately -20 to -40°C are controlled by the automobile manufacturers. For example, a drop ball test at -30°C is used to evaluate the adhesion of sound damping elements in cold weather. Furthermore, good adhesion of these vibration and noise damping elements onto substrates is required at room temperature as well.

[0012] These vibration and noise damping elements are often provided in the form of a multi-component rubber compound stack, with a protective film, typically a siliconized protective film, on each adhesive layer to prevent the single elements from sticking to each other. However, during transportation and / or storage, especially at temperatures between 30 and 50° C., current rubber-based damping elements suffer from lateral leakage of the adhesive layer and / or the damping layer, which prevents later separation and unstacking of the single elements, possibly without damage. Summary of the Invention [Problem to be solved by the invention]

[0013] There is therefore a need for a new type of vibration and noise damping element which ensures easy separation and removal after storage at temperatures between 30 and 50°C, and which preferably exhibits good performance in a ball drop test at low temperatures, in particular at -30°C, preferably has good adhesion to the substrate to which it is applied, and which provides good vibration and noise damping performance. [Means for solving the problem]

[0014] The object of the present invention is to provide a vibration and noise damping element which ensures easy separation and removal after storage at temperatures between 30 and 50°C, preferably exhibits good performance in a drop ball test at low temperatures, in particular at -30°C, preferably has good adhesion to the substrate to which it is applied, and gives good vibration and noise damping performance.

[0015] The subject of the invention is a vibration and noise damping element as defined in claim 1.

[0016] It has further surprisingly been found that the vibration and noise damping elements according to the invention exhibit comparable or even improved vibration and noise damping performance compared to commercially available rubber-based vibration and noise damping elements. In particular, it has been found that the vibration and noise damping elements according to the invention exhibit high vibration damping performance (defined by loss factor at temperatures in the range of approximately 10-20° C.), thereby making them particularly suitable for use in the vibration and noise damping of automotive structures and components.

[0017] Further subject matter of the invention is set out in the other independent claims. Preferred embodiments of the invention are set out in the dependent claims. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a cross-sectional view showing a vibration and noise damping element (1) including a damping layer (2) having a first surface (3) and a second surface (3'), and an adhesive layer (4) covering the first surface (3) of the damping layer (2). [Diagram 2] FIG. 1 is a cross-sectional view showing a vibration and noise damping element (1) including a damping layer (2) having a first surface (3) and a second surface (3'), an adhesive layer (4) covering the first surface (3) of the damping layer (2), and a constraining layer (5) covering the second surface (3') of the damping layer (2). [Diagram 3] FIG. 1 is a cross-sectional view showing a vibration-damped system including a substrate (6) having a noise-generating surface (7) and a vibration and noise-damping element (1) including a damping layer (2) and an adhesive layer (4), where a first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via the adhesive layer (4). [Figure 4]FIG. 1 is a cross-sectional view showing a vibration-damped system including a substrate (6) having a noise-generating surface (7) and a vibration and noise-damping element (1) including a damping layer (2), an adhesive layer (4), and a constraining layer (5), where a first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via the adhesive layer (4), and where the damping layer (2) is sandwiched between the adhesive layer (4) and the constraining layer (5). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The subject of the present invention is a vibration and noise damping element (1) comprising: i) a damping layer (2) having a first surface (3) and a second surface (3'); and ii) an adhesive layer (4) covering at least a portion of the first surface (3) of the damping layer (2);

[0020] The damping layer (2) is composed of a damping layer material which comprises at least one rubber constituent Ru and has a viscosity at 60° C. of 30,000 to 500,000 Pa·s, and the adhesive layer (4) is composed of an adhesive layer material which comprises at least one rubber constituent Ru and has a viscosity at 60° C. of 50,000 to 300,000 Pa·s. The viscosity is measured oscillographically according to DIN 54458 by means of a rheometer with heatable plates (gap: 500 μm, measuring plate diameter: 25 mm (plate / plate), deformation: 1%, angular frequency: 10 rad / s).

[0021] If the viscosity of the damping layer material at 60°C is less than 30,000 Pa·s, the stackability performance will be insufficient. On the other hand, if the viscosity at 60°C is more than 500,000 Pa·s, the adhesion, especially to metal surfaces, will be insufficient. This can be seen, for example, by comparing Ref. 4 with Ex. 1 and Ex. 2 in Table 4.

[0022] It is also preferred that the damping layer material has a viscosity at 100°C of 20,000 to 150,000 Pa·s, preferably 25,000 to 100,000 Pa·s, and most preferably 30,000 to 50,000 Pa·s.

[0023] Furthermore, if the viscosity of the adhesive layer material at 60°C is less than 50,000 Pa·s, the stacking performance is also insufficient. Furthermore, if the viscosity at 60°C is higher than 300,000 Pa·s, the adhesion is insufficient and the low temperature drop ball test performance is also insufficient. This can be understood by comparing Ref.2 and Ref.3 with Ex.1 in Table 4.

[0024] It is even more preferred if the adhesive layer material has a viscosity at 100°C of 60,000 to 200,000 Pa·s, preferably 65,000 to 150,000 Pa·s, and most preferably 70,000 to 100,000 Pa·s.

[0025] The ratio (d1 / d2) of the thickness d1 of the damping layer (2) to the thickness d2 of the adhesive layer (4) is 0.6 to 4.0. Surprisingly, it was found that a ratio lower than 0.6 results in poor stacking performance. In addition, a ratio higher than 4.0 results in poor low temperature ball drop test performance, which can be seen by comparing Ref.1 and Ref.6-8 with Ex.1 and Ex.3.

[0026] The (d1 / d2) is preferably 0.8 to 3.0, more preferably 1.2 to 2.5. This is advantageous for good stacking performance. This can be understood by comparing Ex.1 with Ex.3 in Table 4.

[0027] The sum (d1+d2) of the thickness d1 of the damping layer (2) and the thickness d2 of the adhesive layer (4) is 0.5 to 2.5 mm. It was found that if the sum is less than 0.5 mm, the adhesiveness is insufficient. On the other hand, if the sum is more than 2.5 mm, the ball drop test performance at low temperature is insufficient. This can be understood by comparing Ref.9 with Ex.1 and Ex.4 to 6.

[0028] It is advantageous if the total thickness (d1+d2) is 0.75 to 2.1 mm, preferably 1.25 to 1.9 mm, which provides high adhesive strength, as seen in the comparison of Ex.1 with Ex.4 to Ex.6.

[0029] A cross-sectional view of a vibration and noise damping element according to the invention is shown in FIG.

[0030] In one or more embodiments, the damping layer is a sheet-like element having first and second major surfaces defining a thickness therebetween and having a length and width at least 5 times, preferably at least 15 times, more preferably at least 25 times the thickness of the sheet-like element. The term "thickness" preferably refers to a dimension of the sheet-like element measured in a plane perpendicular to the length and width dimensions of the element. In embodiments in which the damping layer is a sheet-like element, the first and second surfaces of the damping layer correspond to the first and second major surfaces of the sheet-like element.

[0031] The damping layer and the adhesive layer are preferably directly connected to each other over their opposing surfaces. The expression "directly connected" is to be understood in the context of the present invention to mean that there are no further layers or materials between the two layers and that the opposing surfaces of the layers are directly attached to each other. In one or more embodiments, the adhesive layer covers at least 50%, preferably at least 65%, more preferably at least 75% of the first surface of the damping layer. In one or more further embodiments, the adhesive layer covers substantially the entire area of ​​the first surface of the damping layer. The expression "substantially the entire area" is to be understood to mean at least 90%, preferably at least 95%, more preferably at least 98.5% of the total area.

[0032] Preferably, the damping layer material is not the same as the adhesive layer material.

[0033] The adhesive layer (4) is composed of an adhesive layer material containing at least one rubber component Ru and having a viscosity of 50,000 to 300,000 Pa·s at 60° C. The adhesive layer material preferably has a viscosity of 60,000 to 200,000 Pa·s, preferably 65,000 to 150,000 Pa·s, and most preferably 70,000 to 100,000 Pa·s at 60° C.

[0034] The thickness d2 of the adhesive layer (4) is preferably 0.25 to 0.85 mm, more preferably 0.35 to 0.80 mm, and most preferably 0.45 to 0.75 mm.

[0035] It is further preferred if the adhesive layer material has an adhesion of 3 or less, preferably 2 or less, most preferably 1. The adhesion is measured by a ball drop test at -30°C according to Volkswagen Group standard: quality requirements, self-adhesive stiffening pads and sound deadening pads, QP M052, page 12, point 3.7.5, Ball drop test / determination of cold adhesion ("Kugelfall / Bestimmung der Kaerltehaftung"), PV 3971, 2020-03 edition, where the test samples used are 7 cm x 7 cm x 1.7 mm long / width / thickness adhesive layer material with a 0.3 mm thick aluminum layer on top of the adhesive layer material. It is more preferred to measure the adhesion as described in the experimental section.

[0036] The adhesive layer material includes at least one rubber component Ru.

[0037] A preferred rubber component Ru is selected from the list of rubbers LR which are liquid at 25° C. and selected from the group consisting of polybutene which is liquid at 25° C. and polyisobutylene which is liquid at 25° C., butyl rubber BR, natural or synthetic polyisoprene PI, nitrile rubber NBR, ethylene-propylene terpolymer EPDM, ethylene-propylene copolymer EPM, and chloroprene rubber CR, and is preferably selected from the list of rubbers LR which are liquid at 25° C. and selected from the group consisting of polybutene which is liquid at 25° C. and polyisobutylene which is liquid at 25° C., butyl rubber BR, and natural or synthetic polyisoprene PI.

[0038] Preferably, the adhesive layer material is an acoustic dampening material comprising: a) at least one polybutadiene PB containing monomer units derived from 1,3-butadiene in an amount of 0.75% by weight or more, based on the total weight of the acoustic damping material; [ka] wherein the proportion of monomer units of formula (I) among all monomer units derived from 1,3-butadiene present in the polybutadiene is from 25 to 75 mole percent, the proportion of units of formula (II) among all monomer units derived from 1,3-butadiene present in the polybutadiene is from 0 to 10 mole percent, and the proportion of monomer units of formula (III) among all monomer units derived from 1,3-butadiene present in the polybutadiene is from 25 to 75 mole percent, wherein the total of the monomer units (I), (II), and (III) is 100 mole percent, and the polybutadiene preferably has an average molecular weight of from 1000 to 4000 g / mol; b) at least one rubber LR that is liquid at 25° C. selected from the group consisting of polybutene that is liquid at 25° C. and polyisobutylene that is liquid at 25° C., preferably polyisobutylene that is liquid at 25° C., in an amount of 10% by weight or more based on the total weight of the sound-damping material; c) at least 3% by weight of at least one butyl rubber BR, based on the total weight of the sound-damping material; d) 3% by weight or more of at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, most preferably natural rubber, based on the total weight of the sound-damping material; e) 4 to 15 weight percent, based on the total weight of the acoustic damping material, of at least one hydrocarbon resin HR; f) at least one solid particle filler FM.

[0039] Substance names beginning with "poly" technically refer to substances that contain more than one of the functional groups in their names per molecule. For example, a polyol is a compound that has at least two hydroxyl groups. A polyether is a compound that has at least two ether groups.

[0040] The term "polymer" refers to a chemically homogeneous group of macromolecules produced by polymerization reactions (polymerization, polyaddition, polycondensation), where the macromolecules differ in degree of polymerization, molecular weight, and chain length. The term also includes derivatives of said generic macromolecules resulting from polymerization reactions, i.e., compounds obtained, for example, by addition or substitution reactions of functional groups in a predefined macromolecule, and which may be chemically homogeneous or chemically heterogeneous.

[0041] The term "molecular weight" refers to the molar mass (g / mol) of a molecule or a part of a molecule (also called a "moiety"). The term "average molecular weight" refers to the number average molecular weight (M nThe molecular weight can be determined by conventional methods, preferably gel permeation chromatography (GPC), using polystyrene as the standard, styrene-divinylbenzene gels with porosities of 100 angstroms, 1000 angstroms, and 10000 angstroms, depending on the molecule, as columns, and tetrahydrofuran as solvent at a temperature of 35° C. or 1,2,4-trichlorobenzene as solvent at 160° C.

[0042] "Glass transition temperature" (T g The term glass transition temperature (T) refers to the temperature above which a polymer component becomes soft and pliable and below which it becomes hard and glassy. g ) is preferably measured by dynamic mechanical analysis (DMA) as the peak of the loss modulus (G") curve measured at a frequency of 1 Hz and an applied strain of 0.1%.

[0043] The term "softening point" refers to the temperature at which a compound softens to a rubber-like state or at which crystalline parts of a compound melt. The softening point can be determined by the Ring and Ball measurement performed according to the DIN EN 1238 standard.

[0044] The term "room temperature" refers to a temperature of 23°C.

[0045] Preferably, the acoustic attenuation material is essentially free of bitumen. The expression "essentially free" is understood to mean that the acoustic attenuation contains only trace amounts of bitumen, for example less than 0.5% by weight, preferably less than 0.25% by weight, more preferably less than 0.1% by weight, and even more preferably less than 0.01% by weight, based on the total weight of the acoustic attenuation material. The term "bitumen" in this disclosure refers to heavy hydrocarbon blends having a solid consistency at room temperature. They are usually obtained as vacuum distillation residues from the distillation (topping or vacuum distillation) and / or secondary processing processes, for example, refining processes, which may be pyrolysis and visbreaking, of suitable crude oils. Furthermore, the term "bitumen" also refers to natural and synthetic bitumen, as well as bituminous materials obtained from the extraction of tar and bituminous sand.

[0046] The acoustic dampening material includes at least one polybutadiene PB containing monomer units derived from 1,3-butadiene in an amount of 0.75% by weight or more, based on the total weight of the acoustic dampening material; [ka] wherein the ratio of the units of formula (I) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 25 to 75 mol percent, preferably 50 to 65 mol percent, preferably 59 to 62 mol percent, the ratio of the units of formula (II) in the total monomer units derived from 1,3-butadiene present in the polybutadiene is 0 to 10 mol percent, preferably 1 to 8 mol percent, preferably 2 to 6 mol percent, and It is preferred that the proportion of units of formula (III) present among all monomeric units derived from 1,3-butadiene is between 25 and 75 mole percent, preferably between 25 and 40 mole percent, preferably between 35 and 39 mole percent, provided that the total of all monomeric units (I), (II) and (III) totals 100 mole percent, and that the polybutadiene has an average molecular weight between 1000 and 4000 g / mol, preferably between 1200 and 3500 g / mol, preferably between 1500 and 3000 g / mol.

[0047] In the context of the present invention, the term "polybutadiene" is understood to mean a reaction product obtainable by polymerizing monomer units each having at least two conjugated double bonds, of which, for increased suitability, at least 80%, preferably at least 85%, preferably at least 90%, preferably at least 95%, preferably at least 98%, preferably at least 99%, most preferably at least 99.9%, preferably all, are 1,3-butadiene. Possible further compounds (impurities) may be, for example, alkanes or alkenes having 3 to 5 carbon atoms, in particular propene, 1-butene or 1,2-butadiene.

[0048] The acoustic damping material contains at least one rubber LR that is liquid at 25° C. selected from the group consisting of polybutene that is liquid at 25° C. and polyisobutylene that is liquid at 25° C., preferably polyisobutylene that is liquid at 25° C., in an amount of 10% by weight or more based on the total weight of the acoustic damping material.

[0049] The term "polybutene liquid at 25°C" preferably refers in this disclosure to olefin oligomers containing isobutylene and / or 1-butene and / or 2-butene, the proportions of their C4-olefin isomers may vary depending on the manufacturer and grade.

[0050] The term "polyisobutylene that is liquid at 25°C" preferably refers in this disclosure to polyolefins and olefin oligomers of isobutylene that preferably contain at least 75%, more preferably at least 85%, of repeat units derived from isobutylene.

[0051] Particularly suitable polybutenes and polyisobutylenes that are liquid at 25° C. have an average molecular weight of 5,000 g / mol or less, preferably 3,000 g / mol or less, more preferably 2,500 g / mol or less, even more preferably 2,000 g / mol or less, and still more preferably 1,500 g / mol or less.

[0052] The sound-damping material comprises at least 3% by weight of at least one butyl rubber BR, based on the total weight of the sound-damping material.

[0053] The term "butyl rubber" as used herein refers to a rubber made up of a major portion of C4-C7 monoolefin monomers, preferably isoolefin monomers, and a minor portion, for example up to 30% by weight, of C4-C 14 It refers to a polymer derived from a monomer mixture comprising a multiolefin monomer, preferably a conjugated diolefin. The preferred C4-C7 monoolefin monomer may be selected from the group consisting of isobutylene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 4-methyl-1-pentene, and mixtures thereof, preferably isobutylene.

[0054] The at least one butyl rubber BR is preferably selected from the group consisting of butyl rubber and halogenated butyl rubber, preferably butyl rubber, chlorobutyl rubber and bromobutyl rubber, more preferably butyl rubber and bromobutyl rubber, most preferably bromobutyl rubber.

[0055] The acoustic dampening material comprises at least 3% by weight, based on the total weight of the acoustic dampening material, of at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, and most preferably natural rubber.

[0056] The at least one natural or synthetic polyisoprene PI preferably has an average molecular weight of 100,000 g / mol or more, preferably 100,000 to 2,000,000 g / mol, more preferably 100,000 to 1,000,000 g / mol.

[0057] The acoustic dampening material comprises 4 to 15 weight percent of at least one hydrocarbon resin HR, based on the total weight of the acoustic dampening material.

[0058] The term "hydrocarbon resin" preferably refers herein to synthetic resins produced by polymerizing a mixture of unsaturated monomers obtained from petroleum-based feedstocks, such as natural liquefied gas, gas oil, or by-products of cracking petroleum naphtha. These types of hydrocarbon resins are also known as "petroleum resins" or "petroleum hydrocarbon resins". They also include pure monomeric aromatic resins, which are prepared by polymerizing aromatic monomer feedstocks that have been previously purified to remove color-causing contaminants and precisely control the product composition.

[0059] The at least one hydrocarbon resin HR preferably has the following properties: a softening point, measured using the ring and ball method, according to the definition of the DIN EN 1238 standard, of at least 70°C, preferably at least 80°C, more preferably in the range of 70-180°C, preferably 80-150°C, more preferably 90-120°C, and / or preferably and; - an average molecular weight (M) in the range of 250 to 7500 g / mol, preferably 300 to 5000 g / mol; n ).

[0060] Suitable hydrocarbon resins are commercially available, for example, under the trade names Wingtack® series, Wingtack® Plus, Wingtack® Extra, and Wingtack® STS (all from Cray Valley); Escorez® 1000 series, Escorez® 2000 series, and Escorez® 5000 series (all from Exxon Mobil Chemical); Novares® T series, Novares® TT series, Novares® TD series, Novares® TL series, Novares® TN series, Novares® TK series, and Novares® TV series (all from RUETGERS Novares GmbH); and Kristalex®, Plastolyn®, Piccotex®, Piccolastic®, and Endex® (all from Eastman Chemicals).

[0061] The acoustic damping material includes e) at least one solid particulate filler FM, preferably at least one solid, particulate mineral filler FM.

[0062] It is preferred that the acoustic damping material comprises 5-75% by weight, preferably 15-70% by weight, more preferably 25-65% by weight, even more preferably 35-65% by weight, and still more preferably 40-65% by weight of at least one solid particle filler FM, based on the total weight of the acoustic damping material.

[0063] In one or more embodiments, the at least one solid particle filler FM is selected from the group consisting of calcium carbonate, magnesium carbonate, calcium oxide, talc, kaolin, diatomaceous earth, wollastonite, feldspar, montmorillonite, dolomite, silica, preferably fumed silica, cristobalite, iron oxide, iron nickel oxide, strontium ferrite, barium-strontium ferrite, hollow ceramic spheres, hollow glass spheres, hollow organic spheres, glass spheres, mica, barium sulfate, and graphite.

[0064] The sound-damping material may optionally include additives commonly used in sound-damping materials. Examples of suitable additives include, for example, pigments, thixotropic agents, heat stabilizers, drying agents, and flame retardants. If additives are used, they are preferably present in an amount of 25% by weight or less, more preferably 15% by weight or less, and even more preferably 10% by weight or less of the total weight of the sound-damping material.

[0065] Preferred sound attenuating materials include: - 1 to 15% by weight, preferably 1.5 to 3% by weight, of at least one polybutadiene PB, based on the total weight of the sound-damping material; - 12.5 to 35% by weight, preferably 15 to 20% by weight, of rubber LR, liquid at 25°C, based on the total weight of the sound-damping material; - 4.5 to 15% by weight, preferably 6 to 8% by weight, of at least one natural or synthetic polyisoprene PI, based on the total weight of the sound-damping material; - 4.5 to 15% by weight, preferably 6 to 8% by weight, of at least one butyl rubber BR, based on the total weight of the sound-damping material; - 5 to 12% by weight, preferably 5.5 to 10% by weight, most preferably 6.5 to 9.5% by weight, of at least one hydrocarbon resin HR, based on the total weight of the acoustic damping material; and - 5-75 wt.-%, preferably 40-65 wt.-%, of at least one solid particle filler FM, based on the total weight of the sound-damping material.

[0066] The damping layer (2) is composed of a damping layer material containing at least one rubber component Ru and having a viscosity at 60°C of 30,000 to 500,000 Pa·s. The damping layer material preferably has a viscosity at 60°C of 40,000 to 250,000 Pa·s, preferably 50,000 to 200,000 Pa·s, most preferably 65,000 to 150,000 Pa·s. This is advantageous in terms of improving adhesion. This is disclosed in the comparison between Ex.1 and Ex.2 in Table 4.

[0067] The thickness d1 of the damping layer (2) is preferably 0.4 to 1.5 mm, more preferably 0.7 to 1.3 mm, and most preferably 0.9 to 1.2 mm.

[0068] The damping layer material includes at least one rubber component Ru.

[0069] A preferred rubber component Ru is selected from the list of rubbers LR which are liquid at 25° C. and selected from the group consisting of polybutene which is liquid at 25° C. and polyisobutylene which is liquid at 25° C., butyl rubber BR, natural or synthetic polyisoprene PI, nitrile rubber NBR, ethylene-propylene terpolymer EPDM, ethylene-propylene copolymer EPM, and chloroprene rubber CR, and is preferably selected from the list of rubbers LR which are liquid at 25° C. and selected from the group consisting of polybutene which is liquid at 25° C. and polyisobutylene which is liquid at 25° C., butyl rubber BR, and natural or synthetic polyisoprene PI.

[0070] More preferably, the damping layer material comprises: 10 to 18% by weight, based on the total weight of the damping layer material, of at least one rubber LR that is liquid at 25°C selected from the group consisting of polybutene that is liquid at 25°C and polyisobutylene that is liquid at 25°C, preferably polyisobutylene that is liquid at 25°C; 2-5% by weight of at least one butyl rubber BR, based on the total weight of the damping layer material; 0.5-3 wt. %, based on the total weight of the damping layer material, of at least one natural or synthetic polyisoprene PI, preferably natural polyisoprene, most preferably natural rubber; 5-10% by weight, based on the total weight of the damping layer material, of at least one hydrocarbon resin HR; 50-80 wt. % of at least one solid particle filler FM, based on the total weight of the damping layer material.

[0071] The rubber LR which is liquid at 25°C selected from the group consisting of polybutene which is liquid at 25°C and polyisobutylene which is liquid at 25°C, butyl rubber BR, natural or synthetic polyisoprene PI, hydrocarbon resin HR, and solid particle filler FM have previously been considered as preferred compositions for the sound damping material.

[0072] Another subject of the invention is the use of a vibration and noise damping element (1) according to the invention for damping vibrations and / or noise in transport vehicles or white goods.

[0073] Preferably, the vibration and noise damping element has the following properties: - Temperature at which the maximum loss factor is measured (T@LF max ) is between 5°C and 25°C, preferably between 15°C and 25°C; and - Maximum Loss Factor (LF max ) is 0.3 or more, preferably 0.35 or more, preferably 0.39 or more, preferably 0.40 or more, and most preferably 0.41 or more.

[0074] The loss factor is preferably determined using the measurement method specified in the ISO 6721 standard, more preferably using the measurement method described in the experimental section.

[0075] In preferred embodiments, the vibration and noise damping element further includes, in addition to the damping layer and the adhesive layer, a constraining layer covering at least a portion of the second surface of the damping layer. The vibration and noise damping element in these embodiments is generally referred to as a "constrained layer damper." The damping layer and the constraining layer are preferably directly bonded to each other at their opposing surfaces, and the damping layer is preferably sandwiched between the adhesive layer and the constraining layer. In one or more embodiments, the constraining layer substantially, preferably completely, covers the entire area of ​​the second surface of the damping layer. A cross-sectional view of a vibration and noise damping element according to these embodiments is shown in FIG. 2.

[0076] In one or more embodiments, the constraining layer is a metal sheet, preferably an aluminum or steel sheet, or a polymer sheet, preferably a glass fiber reinforced polymer sheet. The constraining layer is preferably a metal sheet, more preferably an aluminum sheet.

[0077] There is no particular limit to the thickness d3 of the constraining layer, but it is generally preferred to use a constraining layer that is thinner than the damping layer. The preferred thickness also depends on the material of the constraining layer. In one or more embodiments, the constraining layer has a thickness of 0.05 to 1.5 mm, preferably 0.1 to 1.25 mm, and more preferably 0.1 to 1.0 mm.

[0078] Most preferably, the constraining layer is a metal sheet having a thickness d3 of 0.05 to 0.6 mm, preferably 0.1 to 0.5 mm, more preferably 0.2 to 0.4 mm.

[0079] In one or more further embodiments, the constraining layer is a polymer sheet having a thickness of 0.1 to 1.2 mm, preferably 0.25 to 1.0 mm.

[0080] It is preferred that the constraining layer has a modulus of elasticity that is higher than the modulus of elasticity of the damping layer, for example at least three times, preferably at least five times, more preferably at least ten times, where the modulus of elasticity is measured using the method specified in the ISO 6892-1:2016 standard (for metal sheets) or the ISO 527-2 standard (for polymer sheets).

[0081] In a preferred embodiment, the vibration and noise damping element comprises a damping layer, an adhesive layer, and a constraining layer.

[0082] In another preferred embodiment, a protective film is additionally included on the side of the adhesive layer that is not in contact with the damping layer. The protective film is preferably a release liner. Such a release liner is preferably peeled off with easy peelability, does not stick strongly, and does not make it difficult to remove from the adhesive layer. The protective film can be made of various materials, but is preferably distinct from the composition used to prepare the adhesive layer. More specifically, the material used for the protective film is selected from the group consisting of paper, silicone or fluorocarbon treated materials, polyester, polyvinyl chloride, cellulose acetate, polypropylene, polyethylene, and polyethylene terephthalate films. It is preferred that the protective film is made of a silicon-based material.

[0083] Preferred sizes for the vibration and noise dampening elements are elements with a length and width of 20-1000mm, more preferably 50-500mm, most preferably 100-400mm.

[0084] Another subject of the invention is a method for applying a vibration and noise damping element according to the invention to a noise-generating surface of a substrate, said method comprising the following steps: I) providing a vibration and noise damping element according to the invention, II) contacting an outer major surface of the adhesive layer of the vibration and noise damping element with the noise generating surface and applying sufficient pressure to form an adhesive bond; or II') heating the adhesive layer and / or the substrate, contacting an outer major surface of the adhesive layer with the noise producing surface, and allowing the adhesive layer to cool thereby forming an adhesive bond.

[0085] The term "outer main surface" of the adhesive layer refers to the main surface of the adhesive layer on the side opposite to the side of the damping layer. The substrate with the noise-generating surface may be various types of molded articles, such as, for example, panels, sheets, or films, composed of, for example, metal, plastic, or fiber-reinforced plastic. Heating of the adhesive layer and / or substrate in step II') can be carried out in various conventional ways, such as, for example, heating in an oven, heating by air flow, or heating with infrared (IR) radiation.

[0086] Yet another subject of the invention is a vibration-damped system comprising a substrate (6) having a noise-generating surface (7) and a vibration and noise damping element (1) according to the invention, in which at least a part of the first surface (3) of the damping layer (2) is adhesively bonded to the noise-generating surface (7) via an adhesive layer (4). A cross-sectional view of the vibration-damped system is shown in FIG.

[0087] In one or more embodiments, the vibration and noise damping element (1) is a constrained damping element including a constraining layer (5), where the damping layer (2) is sandwiched between an adhesive layer (4) and a constraining layer (5). A cross-sectional view of a vibration damped system according to this embodiment is shown in Figure 4.

[0088] In one or more embodiments, the substrate having a noise-generating surface is part of the structure of an automobile or white goods. EXAMPLES

[0089] The products shown in Tables 2 and 3 below were used in the examples in Tables 4 and 5.

[0090] [Table 1]

[0091] Preparation of material composition The adhesive layer material compositions AC1, AChv (high viscosity) and AClv (low viscosity), as well as the damping layer material compositions DC1, DChv (high viscosity) and DClv (low viscosity) used in Ex.1 to Ex.6 shown in Tables 4 and 5, and also in reference examples Ref.1 to Ref.9, were prepared according to the following procedure.

[0092] In a first step, the components for the adhesive layer material composition were mixed with the following components:

[0093] [Table 2]

[0094] In the first step, the components BR, PI, HR, and half of the calcite were mixed in a batch type mixer. The remaining ingredients were then added at a constant rate over a period of one hour and mixed for 20 minutes. The mixed composition was then stored in an unsealed drum and used immediately after mixing.

[0095] In a second step, the components for the damping layer material composition were mixed with the following components:

[0096] [Table 3]

[0097] In the first step, the components BR, PI, HR, and half of the calcite were mixed in a batch type mixer. The remaining ingredients were then added at a constant rate over a period of one hour and mixed for 20 minutes. The mixed composition was then stored in an unsealed drum and used immediately after mixing.

[0098] For the following tests, test samples (vibration and noise damping elements) were prepared using the adhesive layer (if present), the damping layer over the adhesive layer (if present), the aluminum layer (constraining layer), the ratio of the thickness of the damping layer d1 to the thickness of the adhesive layer d2 (d1 / d2), and the sum of the thickness of the damping layer d1 and the thickness of the adhesive layer d2 (d1+d2). The test sample configurations, as well as the test results, are shown in Tables 4 and 5.

[0099] viscosity The viscosity was determined oscillographically by means of a rheometer with heatable plates (MCR 301, Anton Paar) in accordance with DIN 54458 (gap: 500 μm, measuring plate diameter: 25 mm (plate / plate), deformation: 1%, angular frequency: 10 rad / s, temperature: 60° C. or 100° C.).

[0100] Measurement of high temperature resistance ("ht resistance") The heat resistance tests at 210°C were carried out according to the BMW Group standard: "Adhesives and sealing materials used in the body shop Damping pad", Requirements and testing, GS 97028-16:2012-02, page 4, Table 1: Resistance to high temperature ("Waermetest"), AA-0415, edition 2018-10. The length x width of the test samples was 16 cm x 7 cm.

[0101] Grading system: To get a rating of OK, there must be no blistering, no melting, no slippage, and no shrinkage.

[0102] Measurement / quantification of adhesion at low temperatures by a drop ball test at -30°C ("Bdt-30°C") The ball drop test at -30°C was carried out in accordance with the Volkswagen Group standard: Quality requirements for self-adhesive curing pads and sound-deadening pads, QP M052, page 12, point 3.7.5, Ball drop test / measurement of cold adhesives ("Kugelfall / Bestimmung der Kaerltehaftung"), PV 3971, edition 2020-03. The length x width of the test samples was 7 cm x 7 cm.

[0103] Evaluation method: Rating 1: No cracking or splintering of the test specimen, no chipping of the test sheet Rating 2: Cracking or splintering of the test specimen, but no chipping of the test sheet Rating 3: No chipping from the test sheet, but the test specimen may delaminate from the test sheet when subjected to a slight bending load. Rating 4: Cracking or splintering of the test specimen, partial chipping from the test sheet Rating 5: Cracking or splintering of the test specimen, large chipping from the test sheet Rating 6: Complete delamination from the test sheet.

[0104] Adhesion / peel strength measurements ("peel strength") The peel strength tests were carried out according to the BMW Group standard: Adhesives and sealing materials used in the body shop. Damping pad, Requirements and testing, GS 97028-16:2012-02, page 4, Table 1: Adhesion ("Peel-resistance of sound deadening and stiffening matgerials in the body shop"), AA-0007, Edition 2018-10. The length x width of the test samples was 20 cm x 3 cm. In addition, the failure patterns were visually checked.

[0105] Evaluation method: - On oiled steel plate, after 30 minutes, at room temperature: >1.5N / cm - On oiled steel plate, after 30 minutes, 195℃:>4N / cm

[0106] Measurement of loss factor ("loss factor") The loss factor of the test specimens was measured using the measurement method specified in the ISO 6721 standard. The measurement was performed using a commercially available loss factor tester at the anti-resonance point of 200 Hz and in the temperature range of 20 to 60° C. The length and width of the test samples were 20 cm x 1 cm.

[0107] It is advantageous if the maximum values ​​of the loss factors in Tables 4 and 5 are measured at 10°C or 20°C, preferably at 20°C, since this is the most common operating temperature in vehicles.

[0108] Stackability Ten specimens of each type of test sample, measuring 100 mm x 100 mm (length / width) and having a release liner made of a siliconized protective film on each adhesive layer, were stacked on top of each other between two glass panels, subjected to a load of 75 N, and aged at 50°C for 24 hours in a forced air oven.

[0109] Three specimens each were examined under a microscope with a magnification of 20x at 10 different locations on the edge of the specimen to determine the average distance (in mm) of side leakage of the adhesive layer and / or damping layer. Specimens with an average distance value greater than 0.90mm were difficult to separate or remove.

[0110] [Table 4]

[0111] [Table 5]

Claims

1. A vibration and noise attenuation element (1), i) a damping layer (2) having a first surface (3) and a second surface (3'), and ii) an adhesive layer (4) covering at least a part of the first surface (3) of the damping layer (2), comprising; The damping layer (2) is composed of a damping layer material having a viscosity at 60°C of 30,000 to 500,000 Pa·s and containing at least one rubber component Ru; and The adhesive layer (4) is composed of an adhesive layer material having a viscosity at 60°C of 50,000 to 300,000 Pa·s and containing at least one rubber component Ru; and The ratio (d1 / d2) of the thickness d1 of the damping layer (2) to the thickness d2 of the adhesive layer (4) is 0.6 to 4.0; and The sum (d1 + d2) of the thickness d1 of the damping layer (2) and the thickness d2 of the adhesive layer (4) is 0.5 to 2.5 mm; The viscosity is measured by an oscillograph method by means of a rheometer having a heatable plate (gap: 500 μm, measuring plate diameter: 25 mm (plate / plate), deformation: 1%, angular frequency: 10 rad / s) in accordance with DIN 54458; A vibration and noise attenuation element (1).

2. The vibration and noise attenuation element (1) according to claim 1, wherein the damping layer material has a viscosity at 60°C of 40,000 to 250,000 Pa·s, preferably 50,000 to 200,000 Pa·s, and most preferably 65,000 to 150,000 Pa·s.

3. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the adhesive layer material has a viscosity at 60°C of 60,000 to 200,000 Pa·s, preferably 65,000 to 150,000 Pa·s, and most preferably 70,000 to 100,000 Pa·s.

4. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the damping layer material is not the same as the adhesive layer material.

5. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the ratio (d1 / d2) of the thickness d1 of the damping layer (2) to the thickness d2 of the adhesive layer (4) is 0.8 to 3.0, preferably 1.2 to 2.

5.

6. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the sum (d1 + d2) of the thickness d1 of the damping layer (2) and the thickness d2 of the adhesive layer (4) is 0.75 to 2.1 mm, preferably 1.25 to 1.9 mm.

7. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the damping layer material has a viscosity at 100 ° C of 20,000 to 150,000 Pa·s, preferably 25,000 to 100,000 Pa·s, and most preferably 30,000 to 50,000 Pa·s.

8. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the adhesive layer material has a viscosity at 100 ° C of 60,000 to 200,000 Pa·s, preferably 65,000 to 150,000 Pa·s, and most preferably 70,000 to 100,000 Pa·s.

9. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the thickness d1 of the damping layer (2) is 0.4 to 1.5 mm, preferably 0.7 to 1.3 mm, and more preferably 0.9 to 1.2 mm.

10. The vibration and noise attenuation element (1) according to claim 1 or 2, wherein the thickness d2 of the adhesive layer (4) is 0.25 to 0.85 mm, preferably 0.35 to 0.80 mm, and more preferably 0.45 to 0.75 mm.

11. The adhesive layer material conforms to the specifications, quality requirement performance, self-adhesive hardening pads and sound insulation pads of the Volkswagen Group, QP M052, page 12, point 3.7.5 Drop ball test / measurement of cold adhesives ("Kugelfall / Bestimmung der Kaerltenschaftung"), PV 3971, version 2020-03. When measured by a drop ball test at -30°C using a test sample with a length / width / thickness of the adhesive layer material of 7 cm × 7 cm × 1.7 mm and having an aluminum layer with a thickness of 0.3 mm on the adhesive layer material, the vibration and noise attenuation element (1) according to claim 1 or 2 has an adhesiveness of 3 or less, preferably 2 or less, and most preferably 1.

12. The vibration and noise attenuation element (1) according to claim 1 or 2, further comprising a restraint layer (5) covering at least a part of the second surface of the attenuation layer (2).

13. The vibration and noise attenuation element (1) according to claim 12, wherein the attenuation layer and the restraint layer (5) are directly joined to each other over their facing surfaces, and preferably the attenuation layer (2) is sandwiched between the adhesive layer (4) and the restraint layer (5).

14. The restraint layer (5) is a metal sheet, preferably an aluminum or steel sheet, or a polymer sheet, preferably a glass fiber reinforced polymer sheet, most preferably a metal sheet, and the thickness d3 of the restraint layer (5) is 0.05 to 0.6 mm, preferably 0.1 to 0.5 mm, more preferably 0.2 to 0.4 mm. The vibration and noise attenuation element (1) according to claim 12.

15. The vibration and noise attenuation element (1) according to claim 1 or 2, having the following properties: - The temperature (T@LF ｍａｘ ) at which the maximum loss factor is measured is 5°C to 25°C, preferably 15°C to 25°C; and - The maximum loss factor (LF ｍａｘThe value of () is 0.3 or more, preferably 0.35 or more, preferably 0.39 or more, preferably 0.40 or more, and most preferably 0.41 or more, and the loss coefficient is determined using the measurement method defined in ISO 6721 standard.

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