JP5675520B2 - Adhesive damping material - Google Patents

Description

  The present invention relates to a sticking type vibration damping material, and more particularly to a sticking type vibration damping material used in various industrial fields.

  Conventionally, a thin plate is used as a part of a part in a car or home appliance, and a vibration sound of the thin plate is generated when the car is operated or when the home appliance is operated. Therefore, in order to prevent the generation of this vibration sound, it is known to improve the damping performance of the thin plate, for example, by sticking a damping sheet having a resin layer (viscoelastic body) to the thin plate.

  In addition, a thin plate disposed in the vicinity of a motor of an automobile engine room or a home appliance is likely to be high in temperature, and therefore, a damping sheet (damping material) that can exhibit a damping effect even at high temperatures is desired. .

  In order to cause the damping material to exhibit a damping effect at a high temperature, for example, it is conceivable that the glass transition temperature of the viscoelastic body used in the damping material is made higher than room temperature. For example, by setting the glass transition temperature of the viscoelastic body used for the damping material to, for example, about room temperature to about 100 ° C., the damping effect can be expressed in the engine room of the automobile.

  However, such a vibration damping material is excellent in vibration damping properties at high temperatures, but is inferior in adhesiveness at room temperature. Therefore, there is a problem that heating is required for sticking the vibration damping material and workability is poor.

  As a vibration damping material that ensures vibration damping properties at high temperatures and can be stuck at room temperature, for example, a high-melt constraining layer made of aluminum foil and a hot melt adhesive containing EPDM rubber that is a non-thermoplastic resin, And an intermediate constraining layer made of a vulcanized rubber blend containing a reinforcing agent such as glass fiber, and a low-elastic adhesive layer containing butyl rubber and polybutene and having adhesiveness to a braking body, A vibration damping sheet has been proposed (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 5-220883

  However, the vibration damping effect of the above vibration damping sheet under high temperature is effectively expressed against low-frequency vibrations, but cannot sufficiently cope with vibrations in a wide frequency range including high frequencies. In the industrial field, there is a demand for a vibration damping sheet having vibration damping performance superior to that of the above vibration damping sheet.

  An object of the present invention is to provide a sticking type vibration damping material having further improved vibration damping properties.

  In order to achieve the above object, an adhesive vibration damping material of the present invention comprises a constraining layer, a vibration damping layer laminated on the constraining layer, and a pressure-sensitive adhesive layer laminated on the vibration damping layer. An adhesive vibration damping material, wherein the vibration damping layer comprises a thermoplastic resin composition, the thermoplastic resin composition comprising a thermoplastic resin having a melting point of 23 ° C. or higher, and the thermoplastic resin. The adhesive type damping material includes a polymer having a glass transition point below the melting point, a tackifier, and a filler, and the loss at a thickness of 2.2 mm and a frequency of 500 Hz is measured by a central vibration method. The coefficient is 0.1 or more at all temperatures of 20 to 60 ° C., and the adhesive strength by a 90-degree peel test on a stainless steel plate measured at 23 ° C. at a peeling rate of 300 mm / min in accordance with JIS Z0237. , 0.1N / 25mm or more It is characterized.

  In the sticking type damping material of the present invention, it is preferable that the thermoplastic resin is an ethylene copolymer.

  Moreover, in the sticking type | mold damping material of this invention, it is suitable for the said pressure sensitive adhesive layer to contain rubber | gum as a main component.

  Moreover, in the sticking type | mold damping material of this invention, the said rubber | gum is an acryl obtained by polymerizing the monomer component which has a C2-C14 (meth) acrylic acid ester as a main component. Resin rubber is preferred.

  The sticking type damping material of the present invention is a sticking type damping material comprising a constraining layer, a damping layer laminated on the constraining layer, and a pressure-sensitive adhesive layer laminated on the damping layer, The vibration damping layer is made of a thermoplastic resin composition. The thermoplastic resin composition includes a thermoplastic resin having a melting point of 23 ° C. or higher, a polymer having a glass transition point below the melting point of the thermoplastic resin, and tackifying. The adhesive type damping material includes an agent and a filler, and the loss coefficient at a thickness of 2.2 mm and a frequency of 500 Hz measured by the center excitation method is 0.1 at all temperatures of 20 to 60 ° C. As described above, in accordance with JIS Z0237, the adhesive strength in a 90-degree peel test with respect to a stainless steel plate measured at a peeling rate of 300 mm / min and 23 ° C. is 0.1 N / 25 mm or more. Allows room temperature sticking and high temperature In also against vibration in a wide frequency region including the high frequency, it is possible to exhibit excellent vibration damping property.

It is sectional drawing of one Embodiment of the sticking type | mold damping material of this invention. It is sectional drawing of other embodiment of the sticking type | mold damping material of this invention. The dynamic viscoelasticity measurement chart of the damping layer in Example 1 is shown. The dynamic viscoelasticity measurement chart of the damping layer in Example 2 is shown. The dynamic viscoelasticity measurement chart of the damping layer in the comparative example 1 is shown. The dynamic viscoelasticity measurement chart of the damping layer in the comparative example 3 is shown.

  FIG. 1 is a cross-sectional view of an embodiment of the sticking type vibration damping material of the present invention, and FIG. 2 is a cross sectional view of another embodiment of the sticking type vibration damping material of the present invention.

  1 and 2, the sticking type damping material 1 includes a constraining layer 2, a damping layer 3 laminated on the constraining layer 2, and a pressure-sensitive adhesive layer 4 laminated on the damping layer 3. ing.

  The constraining layer 2 constrains and retains the damping layer 3 (and the pressure-sensitive adhesive layer 4 laminated on the damping layer 3), and the damping layer 3 (and the pressure-sensitive adhesive layer laminated on the damping layer 3). 4) toughness is imparted to improve strength.

  The constraining layer 2 is formed of a sheet-like material that is lightweight and thin, and can be closely integrated with the damping layer 3. Examples of such materials include glass cloth, resin-impregnated glass cloth, metal foil, synthetic resin nonwoven fabric, and carbon fiber.

  The glass cloth is made of glass fiber and includes a known glass cloth.

  The resin-impregnated glass cloth is obtained by impregnating the above-described glass cloth with a synthetic resin such as a thermosetting resin or a thermoplastic resin, and includes known ones. In addition, as a thermosetting resin, an epoxy resin, a urethane resin, a melamine resin, a phenol resin etc. are mentioned, for example. Examples of the thermoplastic resin include vinyl acetate resin, ethylene-vinyl acetate copolymer (EVA), vinyl chloride resin, EVA-vinyl chloride resin copolymer, and the like. Moreover, the above-mentioned thermosetting resin and thermoplastic resin can be used alone or in combination, respectively.

  Examples of the metal foil include known metal foils such as an aluminum foil and a steel foil.

  The synthetic resin nonwoven fabric is a nonwoven fabric made of a synthetic resin such as an olefin resin, a polyethylene terephthalate resin, or a polyester resin, and includes known ones.

  The carbon fiber is a fiber made of carbon as a main component, and includes known ones.

Among these constraining layers 2, in consideration of weight, adhesion, strength, and cost, glass cloth is preferably used. The thickness of the constraining layer 2 is, for example, 50 μm to 2 mm. In particular, when a glass cloth is used as the constraining layer 2, the thickness is preferably 300 μm or less, and when a metal foil is used as the constraining layer 2, the thickness is 100 μm or less from the viewpoint of handling. .

Further, the tensile elastic modulus (measurement method: conforming to JIS K 7164) of the constraining layer 2 is, for example, 10 ⁹ Pa or more, preferably 5 × 10 ⁹ Pa or more, more preferably 8 × 10 ⁹ Pa or more. 10 ¹¹ Pa or less.

When the tensile elastic modulus of the constraining layer 2 is 10 ⁹ Pa or more, the vibration damping property by the constraining layer 2 can be sufficiently exhibited, and the vibration damping property of the sticking type vibration damping material 1 can be improved. .

  The vibration damping layer 3 is made of a thermoplastic resin composition. The thermoplastic resin composition is composed of a thermoplastic resin having a melting point of 23 ° C. or higher and a polymer having a glass transition point below the melting point of the thermoplastic resin ( A polymer excluding the thermoplastic resin), a tackifier, and a filler.

  It does not restrict | limit especially as a thermoplastic resin which has melting | fusing point more than 23 degreeC, A well-known thermoplastic resin can be used.

  Specifically, as such a thermoplastic resin, for example, ethylene / vinyl acetate copolymer (vinyl acetate content 10 to 50 mass%) (melting point: 40 to 100 ° C.), ethylene / ethyl acrylate copolymer ( Ethylene-based copolymerization such as an ethyl acrylate content of 9 to 50% by mass (melting point: 80 to 100 ° C.) and the like can be mentioned.

  These thermoplastic resins can be used alone or in combination of two or more.

  The melting point of the thermoplastic resin can be measured by differential scanning calorimetry (DSC).

  The thermoplastic resin is preferably an ethylene copolymer, and more preferably an ethylene / vinyl acetate copolymer.

  If an ethylene-based copolymer, especially an ethylene / vinyl acetate polymer is used, it can be easily mixed with other components, and excellent vibration damping properties can be secured.

  Examples of the polymer having a glass transition point below the melting point of the thermoplastic resin described above include rubber (hereinafter referred to as first rubber).

  The first rubber is not particularly limited, and a known rubber can be used. Specific examples of the rubber include styrene / butadiene rubber such as styrene / butadiene copolymer and hydrogenated styrene / butadiene copolymer (hydrogenated styrene / butadiene rubber), such as styrene / isoprene copolymer (3 , 4-isoprene-styrene copolymer, etc.) and styrene rubber such as styrene-isoprene rubber, and nitrile rubber, for example.

  These first rubbers can be used alone or in combination of two or more.

  Specifically, when ethylene / vinyl acetate copolymer (melting point: 40 to 100 ° C.) is used as the thermoplastic resin, the first rubber preferably has a glass transition point below the melting point. Is mentioned.

  More specifically, when an ethylene / vinyl acetate copolymer (melting point: 40 to 100 ° C.) is used as the thermoplastic resin, the glass transition temperature of the first rubber is, for example, from the melting point of the thermoplastic resin. 0 to 80 ° C., preferably 10 to 60 ° C., and a specific numerical range is, for example, 0 to 80 ° C., preferably 20 to 70 ° C.

  If such a rubber is used as the first rubber, vibration damping can be obtained in a wide temperature range.

  Among the first rubbers, examples of the rubber having such a glass transition point include styrene rubbers such as styrene / butadiene rubber, styrene / isoprene rubber, and the like.

  The glass transition point of the first rubber is defined as the peak of the loss shear elastic modulus G ″ measured by a dynamic viscoelasticity measuring device (measurement conditions: shear mode, temperature rising rate 5 ° C./min, frequency 1 Hz). Is done. The glass transition temperature of the first rubber is a temperature at which the glass transition point is confirmed.

  The blending ratio of the polymer having a glass transition point below the melting point of such a thermoplastic resin is, for example, 50 to 500 parts by mass, preferably 75 to 200 parts by mass with respect to 100 parts by mass of the thermoplastic resin. .

  It does not restrict | limit especially as a tackifier, A well-known tackifier can be used. Specific examples of the tackifier include petroleum resins, terpene resins, rosin resins (such as hydrogenated rosin esters), phenol resins, and coumarone resins.

  These tackifiers can be used alone or in combination of two or more.

  The blending ratio of the tackifier is, for example, 5 to 150 parts by mass, preferably 15 to 15 parts by mass with respect to 100 parts by mass of the total amount of the thermoplastic resin and the polymer having a glass transition point below the melting point of the thermoplastic resin. 100 parts by mass.

  It does not restrict | limit especially as a filler, A well-known filler can be used. Specific examples of the filler include inorganic fillers such as talc, calcium carbonate, clay and mica, metal oxides such as zinc oxide and magnesium oxide, reinforcing fillers such as carbon black and silica, and water. Examples include flame retardants such as aluminum oxide and magnesium hydroxide.

  These fillers can be used alone or in combination of two or more.

  The blending ratio of the filler is, for example, 5 to 300 parts by mass, preferably 15 to 200 parts per 100 parts by mass of the total amount of the thermoplastic resin and the polymer having a glass transition point below the melting point of the thermoplastic resin. Part by mass.

  Moreover, in order to adjust the glass transition temperature, the damping layer 3 can be further blended with, for example, a softening agent and a plasticizer.

  The softening agent is not particularly limited, and a known softening agent can be used. Specific examples of the softening agent include process oil, naphthenic oil, polybutene (polybutene rubber), and the like.

  These softeners can be used alone or in combination of two or more.

  The blending ratio of the softening agent is, for example, 100 parts by mass or less, preferably 1 to 50 parts by mass with respect to 100 parts by mass of the total amount of the thermoplastic resin and the polymer having a glass transition point below the melting point of the thermoplastic resin. Part.

  It does not restrict | limit especially as a plasticizer, A well-known plasticizer can be used. Specific examples of the plasticizer include phthalic acid esters, adipic acid esters, oils, and the like.

  These plasticizers can be used alone or in combination of two or more.

  The blending ratio of the plasticizer is, for example, 100 parts by mass or less, preferably 1 to 50 parts by mass with respect to 100 parts by mass of the thermoplastic resin.

  In addition to the above components, the vibration damping layer 3 may contain, for example, an anti-aging agent, an antioxidant, an ultraviolet absorber, a stabilizer, a lubricant, an anti-scorch agent, a pigment, a colorant, and an antifungal agent. A known additive such as an agent can be blended in an appropriate ratio.

  The method for forming the vibration damping layer 3 is not particularly limited. For example, the above components are mixed at, for example, 80 to 150 ° C., and pressure-molded at, for example, 0.01 to 10 MPa (for example, press molding or roll molding). , Extrusion molding, etc.) can be employed.

  The thickness of the damping layer 3 is, for example, 100 to 5000 μm, preferably 500 to 3000 μm.

  The glass transition temperature of the damping layer 3 is, for example, 0 ° C. or more, preferably 2 ° C. or more, and usually 80 ° C. or less. The specific temperature range is, for example, 0 to 80 ° C., preferably 2 ~ 70 ° C.

  The glass transition point of the damping layer 3 is a peak of the loss shear elastic modulus G ″ measured by a dynamic viscoelasticity measuring device (measurement conditions: shear mode, heating rate 5 ° C./min, frequency 1 Hz). Defined. Moreover, the glass transition temperature of the damping layer 3 is a temperature at which the glass transition point is confirmed.

Further, the damping layer 3 has a storage shear modulus G ′ of 20 to 80 ° C., preferably 20 to 100 ° C., for example, 10 ⁴ to 10 ⁹ Pa, preferably 10 ⁵ to 10 ^8. It is the range of Pa.

  If the storage shear modulus G ′ of the damping layer 3 is in the above range, damping properties can be obtained in a wide temperature range.

  The storage shear elastic modulus G ′ of the damping layer 3 is measured by a dynamic viscoelasticity measuring device (measurement conditions: shear mode, temperature rising rate 5 ° C./min, frequency 1 Hz).

  The pressure sensitive adhesive layer 4 is made of, for example, a known pressure sensitive adhesive.

  Although it does not restrict | limit especially as an adhesive, From the viewpoint of normal temperature adhesiveness and workability | operativity, Preferably, the adhesive which contains rubber | gum (henceforth a 2nd rubber | gum) as a main component is mentioned.

  Examples of the second rubber include acrylic resin rubber.

  The acrylic resin rubber can be obtained by polymerizing a monomer component mainly composed of (meth) acrylic acid ester.

  The (meth) acrylic acid ester which is the main component of the monomer component is a methacrylic acid ester and / or an acrylic acid ester, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate Isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, (meth) Neopentyl acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate , Isononyl (meth) acrylate, decyl (meth) acrylate, (meth) Acrylic acid isodecyl, (meth) acrylate, lauryl (meth) bornyl acrylate, (meth) acrylic acid isobornyl (meth) acrylate, myristyl (meth) acrylate, pentadecyl, and the like (meth) stearyl acrylate.

  These (meth) acrylic acid esters can be used alone or in combination of two or more.

  The (meth) acrylic acid ester is preferably a (meth) acrylic acid ester having 2 to 14 carbon atoms in the alkyl group, more preferably a (meth) acrylic acid ester having 2 to 8 carbon atoms in the alkyl group. More preferably, (meth) acrylic acid ester having 4 to 6 carbon atoms in the alkyl group may be mentioned.

  If the carbon number of the alkyl group of the (meth) acrylic acid ester is within the above range, excellent ordinary temperature adhesiveness can be secured.

  Moreover, as a monomer component, you may use together the monomer copolymerizable with (meth) acrylic acid ester other than above-described (meth) acrylic acid ester. Examples of such a copolymerizable monomer include a functional group-containing monomer containing a functional group.

  Examples of the functional group-containing monomer include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, and crotonic acid, such as (meth) acrylic acid-2-hydroxyethyl and (meth) acrylic acid-2. -Hydroxypropyl, hydroxyl group-containing monomers such as (meth) acrylic acid-2-hydroxybutyl, such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl ( Amide group-containing monomers such as (meth) acrylamide and N-butoxymethyl (meth) acrylamide, for example, amino group-containing monomers such as diaminoethyl (meth) acrylate, for example, glycidyl group-containing monomers such as glycidyl (meth) acrylate, Others, (meta) Ronitoriru, N- (meth) acryloyl morpholine, N- vinyl-2-Pirodorin the like.

  These functional group-containing monomers can be used alone or in combination of two or more.

  As the functional group-containing monomer, a carboxyl group-containing monomer is preferable.

  Further, as other copolymerizable monomers, for example, vinyl esters such as vinyl acetate, aromatic vinyl compounds such as styrene and vinyl toluene, for example, cyclopentyl di (meth) acrylate, isobornyl (meth) acrylate, etc. (Meth) acrylic esters of cyclic alcohols such as neopentyl glycol di (meth) acrylate, hexanediol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylol And (meth) acrylic acid esters of polyhydric alcohols such as methanetri (meth) acrylate and dipentaerythritol hexa (meth) acrylate.

  These other copolymerizable monomers can be used alone or in combination of two or more.

  As other copolymerizable monomers, vinyl esters are preferably used.

  When these functional group-containing monomers (preferably carboxyl group-containing monomers) and / or other copolymerizable monomers (preferably vinyl esters) are used in combination, their blending ratio is (meta ) The functional group-containing monomer is, for example, 0.1 to 20 parts by mass, preferably 1 to 15 parts by mass with respect to 100 parts by mass of the total amount of acrylic acid ester, and other copolymerizable monomers. For example, it is 0.1-15 mass parts, Preferably, it is 1-10 mass parts.

  The method for synthesizing the second rubber is not particularly limited, and for example, the above components are radically polymerized by a known method such as solution polymerization, emulsion polymerization, suspension polymerization, bulk polymerization and the like.

  Further, in order to further adjust the glass transition temperature, for example, the above-mentioned filler, tackifier, cross-linking agent, softener (plasticizer) and the like can be blended in the pressure-sensitive adhesive. Add agent.

  The compounding ratio of the tackifier is, for example, 150 parts by mass or less, preferably 5 to 100 parts by mass with respect to 100 parts by mass of the second rubber.

  In addition to the above-mentioned components, the pressure-sensitive adhesive includes, for example, an anti-aging agent, an antioxidant, an ultraviolet absorber, a stabilizer, a lubricant, an anti-scorch agent, a pigment, a colorant, and an antifungal agent. These known additives can be blended at an appropriate ratio.

  The method for forming the pressure-sensitive adhesive layer 4 is not particularly limited, and for example, a known method such as casting the pressure-sensitive adhesive prepared as described above can be employed.

  The pressure-sensitive adhesive layer 4 can also be formed, for example, as an adhesive tape in which the above-mentioned adhesive is laminated on the front and back surfaces of the substrate (see, for example, FIG. 2).

  Specifically, as shown in FIG. 2, the pressure-sensitive adhesive layer 4 as the pressure-sensitive adhesive tape has a plurality of layers (three layers) by laminating the pressure-sensitive adhesive layer 4b on each of the front surface and the back surface of the substrate 4a. ) Formed as a structure.

  The substrate 4a is not particularly limited. For example, a polyester film such as a polyethylene terephthalate (PET) film, a polyolefin film such as a polyethylene film or a polypropylene film, a plastic film such as polyvinyl chloride or polystyrene, for example, , Paper such as kraft paper, for example, cloth such as cotton cloth, sufu cloth, for example, woven cloth such as manila hemp, pulp, rayon, acetate fiber, for example, non-woven cloth such as polyester non-woven cloth, vinylon non-woven cloth, for example metal Examples include foil.

  The substrate 4a is preferably paper.

  The thickness of the base material 4a is, for example, 5 to 200 μm, or preferably 10 to 150 μm.

  Moreover, the thickness of each adhesive layer 4b laminated | stacked on the base material 4a is 10-500 micrometers, for example, Preferably, it is 20-300 micrometers.

  The method for forming the pressure-sensitive adhesive layer 4 as a pressure-sensitive adhesive tape is not particularly limited. For example, the pressure-sensitive adhesive (pressure-sensitive adhesive layer 4b) formed as described above is bonded to the front surface and the back surface of the substrate 4a. Any known method can be employed.

  In addition, as the 2nd adhesive layer 4, a commercially available double-sided adhesive tape etc. can also be used.

  The thickness of the pressure-sensitive adhesive layer 4 is, for example, 10 to 500 μm, preferably 20 to 300 μm.

  And although it does not restrict | limit especially in order to form the sticking type | mold damping material 1, For example, the damping layer 3 is laminated | stacked on the surface of the constrained layer 2, and the pressure sensitive adhesive layer 4 is formed on the surface of the damping layer 3 after that. May be laminated.

  Thus, the thickness of the sticking type | mold damping material 1 formed is 1.0-6.0 mm, for example, Preferably, it is 1.5-4.0 mm.

  Such a sticking type damping material 1 has a loss coefficient at a thickness of 2.2 mm and a frequency of 500 Hz, measured by a central vibration method, at a temperature of 20 to 60 ° C., preferably 20 to 80 ° C., more preferably. In all of 20-100 degreeC, it is 0.1 or more, and usually 0.5 or less.

  Specifically, the loss factor of the sticking type damping material 1 is 20 ° C., 40 ° C., and 60 ° C., preferably 0.1 or more at 80 ° C. and 100 ° C. It is considered that the loss coefficient is 0.1 or more in all of 20 to 60 ° C, preferably 20 to 80 ° C, more preferably 20 to 100 ° C.

  If the loss coefficient is within the above range, excellent damping performance can be expressed against vibrations in a wide frequency range including high frequencies even at high temperatures.

  In addition, the loss factor of the sticking type damping material 1 can be measured, for example, using a known loss factor measuring device or the like according to the central vibration method (central support steady vibration method) of JIS G0602.

  Moreover, the sticking type damping material 1 can be stuck to a desired installation location by the pressure-sensitive adhesive layer 4, and its adhesive strength (90-degree peel test on a stainless steel plate (conforming to JIS Z0237), peeling speed of 300 mm / min. , 23 ° C.) is 0.1 N / 25 mm or more, preferably 1 N / 25 mm or more.

  Such a sticking type damping material 1 includes a constraining layer 2, a damping layer 3 laminated on the constraining layer 2, and a pressure-sensitive adhesive layer 4 laminated on the damping layer 3. The vibration layer 3 is made of a thermoplastic resin composition. The thermoplastic resin composition includes a thermoplastic resin having a melting point of 23 ° C. or higher, a polymer having a glass transition point below the melting point of the thermoplastic resin, and tackifying. Agent and filler. And the sticking type | mold damping material 1 is 0.1 or more in all the temperature of 20-60 degreeC in the loss coefficient in thickness 2.2mm and frequency 500Hz measured by the center vibration method, and is JISZ0237. In accordance with the above, the adhesive strength by a 90-degree peel test to a stainless steel plate measured at 23 ° C. at a peeling speed of 300 mm / min is 0.1 N / 25 mm or more. Therefore, the pressure-sensitive adhesive layer can be attached at room temperature, and can exhibit excellent damping properties against vibrations in a wide frequency range including high frequencies even at high temperatures.

  The application temperature of the sticking type vibration damping material 1 is, for example, 20 to 100 ° C., and the vibration frequency to be damped thereby is, for example, 500 to 5000 Hz.

  In addition, the application temperature of the sticking type damping material 1 is determined by measuring the loss coefficient of the sticking type damping material 1 at a desired frequency using a central excitation method, for example, using a loss factor measuring device or the like. it can.

  Specifically, if the loss coefficient of the sticking type damping material 1 at a desired frequency is 0.1 or more under a specific temperature condition, the damping property under the temperature condition is good and sticking. It is determined that the applied temperature and frequency of the vibration damping material 1.

  EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to the examples and comparative examples.

Examples 1-2 and Comparative Examples 1-3
(Formation of damping layer)
In the formulation shown in Table 1, each component was blended on a mass part basis, mixed at 120 ° C., and then pressure-formed by a press so that the thickness became 1.8 mm.

(Formation of pressure-sensitive adhesive layer)
In the formulation shown in Table 1, each component was blended on a mass part basis, polymerized by a known radical polymerization method, and then dissolved in toluene. Next, the obtained toluene solution was cast to a molding thickness of 35 μm, and the obtained adhesive was bonded to the front and back surfaces of 80 μm thick paper (23 g / m ² ).

(Manufacture of adhesive damping material)
A damping layer is thermally bonded at 100 ° C. to the surface of the constraining layer shown in Table 1, and then a pressure sensitive adhesive layer is bonded to the surface of the damping layer. A vibration material was obtained.

  In Comparative Example 2, a vibration damping material was obtained without forming a pressure-sensitive adhesive layer.

なお、表１中の成分またはその略号の詳細を以下に示す。

In addition, the detail of the component in Table 1 or its abbreviation is shown below.

EVA: ethylene / vinyl acetate copolymer (thermoplastic resin, vinyl acetate content 25 mass%, MFR = 15, melting point: 71 ° C.)
SBR1: hydrogenated styrene-butadiene rubber (first rubber (trade name SOE SS9000, manufactured by Asahi Kasei), glass transition point: 10 ° C.)
SBR2: Styrene-butadiene rubber (first rubber (trade name Asaprene 6500P, manufactured by Asahi Kasei), glass transition point: 45 ° C.)
Polybutene: Polybutene rubber (softener)
Tackifier A: Coumarone resin (softening point 90 ° C)
EPDM: ethylene-propylene-diene rubber (non-thermoplastic resin (trade name Esprene 524, manufactured by Sumitomo Chemical Co., Ltd.))
Vulcanization accelerator A: Tetrabutylthiuram disulfide (trade name Noxeller TBT, manufactured by Ouchi Shinsei Chemical Industry)
Vulcanization accelerator B: Di-2-benzothiazolyl disulfide (trade name Noxeller DM, manufactured by Ouchi Shinsei Chemical Industry)
BA: Butyl acrylate VAc: Vinyl acetate AA: Acrylic acid Tackifier B: Hydrogenated rosin ester (softening point 80 ° C.)
(Evaluation)
1) Dynamic viscoelastic modulus measurement Examples 1 and 2 were performed according to a dynamic viscoelasticity measurement apparatus (device name: ARES (manufactured by Rheometric Co., Ltd.), measurement conditions: shear mode, heating rate 5 ° C / min, frequency 1 Hz). The storage shear modulus G ′ and the loss shear modulus G ″ of the damping layer and the pressure-sensitive adhesive layer in Comparative Examples 1 and 3 were measured, and the elastic modulus ratio tan δ (= G ″ / G ′) was obtained. It was.

  Moreover, the glass transition temperature of the damping layer in Examples 1-2 and Comparative Examples 1 and 3 was determined from the peak of the loss shear modulus G ″. The results are shown in Table 1.

  Further, the storage shear modulus G ′ of the damping layer was determined for each of 20 ° C., 40 ° C., 60 ° C. and 80 ° C. (and 100 ° C. for Example 2). The results are shown in Table 1.

  Moreover, the measurement chart by a dynamic viscoelasticity measuring apparatus is shown to FIGS.

3 is a chart of the damping layer in Example 1, FIG. 4 is a chart of the damping layer in Example 2, FIG. 5 is a chart of the damping layer in Comparative Example 1, and FIG. 6 is a comparative example. 3 shows a chart of the damping layer in FIG.
2) Loss coefficient The sticking type damping material having a thickness of 2.2 mm obtained in each example and each comparative example was cut into a size of 10 × 250 mm, and this was cut into a size of 0.8 × 10 × 250 mm. A test piece was obtained by sticking to one side of the cold rolled steel sheet. In addition, since the damping material of the comparative example 2 cannot be stuck at room temperature, it was heat-sealed to one side of a cold-rolled steel plate at 100 ° C.

  Thereafter, the loss coefficient of the sticking type damping material at each temperature of 20 ° C., 40 ° C., 60 ° C., and 80 ° C. (and 100 ° C. for Example 2) is set to center excitation at 500 Hz and 5000 Hz, respectively. Measured by the method. The results are shown in Table 1.

In addition, if the loss coefficient is 0.1 or more, it is determined that the vibration damping property under the temperature condition is good, and that it is the adaptive temperature and frequency of the sticking type damping material.
3) Adhesive strength The sticking type damping material of each example and each comparative example was cut out with a width of 25 mm, and bonded to a stainless steel plate at 1 MPa in a 23 ° C. atmosphere, and the adhesive strength (N / 25 mm) was 90 ° peel test. (Tensile speed 300 mm / min). The results are shown in Table 1.
(Discussion)
A constraining layer, a vibration damping layer laminated on the constraining layer and made of a thermoplastic resin composition, and a pressure-sensitive adhesive layer laminated on the vibration damping layer, a thickness of 2.2 mm measured by a central vibration method, The loss coefficient at a frequency of 500 Hz is 0.1 or more at all temperatures of 20 to 60 ° C., and the adhesion strength by a 90-degree peel test to a stainless steel plate measured at a peeling rate of 300 mm / min and 23 ° C. is 0.00. The sticking type damping material of Examples 1 and 2 that is 1 N / 25 mm or more enables sticking at room temperature with a pressure-sensitive adhesive layer, and also allows vibration in a wide frequency range including high frequencies even at high temperatures. On the other hand, excellent vibration damping properties can be expressed.

  On the other hand, as in Comparative Example 1, the sticking mold control in which the loss coefficient at a thickness of 2.2 mm and a frequency of 500 Hz measured by the central excitation method is less than 0.1 at least at a temperature of 20 to 60 ° C. The vibration member is inferior in vibration damping performance in a high temperature range.

  Moreover, when the thing which does not contain a thermoplastic resin composition is used as a damping layer like the comparative example 3, it is inferior to the damping performance in a high temperature range.

  Further, in the case of only the vibration damping layer as in Comparative Example 2, adhesion at normal temperature cannot be performed, and workability is inferior.

DESCRIPTION OF SYMBOLS 1 Adhesive type damping material 2 Constrained layer 3 Damping layer 4 Pressure-sensitive adhesive layer

Claims (4)

A sticking type vibration damping material comprising a constraining layer, a vibration damping layer laminated on the constraining layer, and a pressure sensitive adhesive layer laminated on the vibration damping layer,
The damping layer is made of a thermoplastic resin composition,
The thermoplastic resin composition includes a thermoplastic resin having a melting point of 23 ° C. or higher, a polymer having a glass transition point below the melting point of the thermoplastic resin, a tackifier, and a filler.
The sticking type damping material is
The loss factor at a thickness of 2.2 mm and a frequency of 500 Hz, measured by the central excitation method, is 0.1 or more at all temperatures of 20 to 60 ° C.,
In accordance with JIS Z0237, the adhesive strength by a 90 degree peel test to a stainless steel plate measured at 23 ° C. with a peeling speed of 300 mm / min is 0.1 N / 25 mm or more. Vibration material.   The sticking type vibration damping material according to claim 1, wherein the thermoplastic resin is an ethylene copolymer.   The sticking type vibration damping material according to claim 1 or 2, wherein the pressure-sensitive adhesive layer contains rubber as a main component. The rubber is an acrylic resin rubber obtained by polymerizing a monomer component mainly composed of a (meth) acrylic acid ester having 2 to 14 carbon atoms in an alkyl group. 3. The sticking type damping material according to 3.

Images