JP2007279649A - Acoustic material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acoustic material whose manufacturing stage can be simplified, and which hardly occur thermally contract, deform or wrinkle caused by that the material is laminated and united and has superior sound absorptivity, moldability, and durability. <P>SOLUTION: An air-permeable acoustic material is provided with: a sound absorbing layer made of short fiber or long fiber non-woven fabric or urethane foam; and a facing layer made of synthetic resin fiber which is sprayed directly by a hot-melt spraying method and bonded to the fiber of the sound absorbing layer. Also an acoustic material is obtained by forming the acoustic material. Those acoustic materials are suitably used for an electric appliance, a diaphragm for speaker, a motor-driven tool, a wall material for civil engineering and building which require sound absorption, etc., not to mention interior materials for vehicle. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sound-absorbing material used in fields such as air conditioners, electric refrigerators, electric appliances, automobiles, and building wall materials, and particularly used in vehicles having noise sources such as automobiles, trains, and aircraft.

  Engines and drive systems mounted on vehicles and the like generate noise when driven. In order to prevent this noise from causing discomfort to the occupant, sound absorbing materials are laminated in layers on the wall surfaces of wall materials such as engine hoods, dash panels, ceiling materials, door trims, cab floors, etc. There are many cases.

  For this reason, it is known that a sound absorbing layer made of a porous material such as a nonwoven fabric or urethane foam is laminated and integrated with a skin layer such as a breathable nonwoven fabric or a resin film (Patent Document). 1-6 etc.).

  In Patent Document 1, a fabric (nonwoven fabric) is laminated on a short fiber web, at least a part of which is a heat-adhesive short fiber, and the two are bonded and integrated by compressing from the web thickness direction and heat-treating. A method is disclosed. Similarly, in Patent Document 2, a laminate is obtained by thermally fusing a fibrous nonwoven fabric or a resin film made of a thermoplastic synthetic resin such as polypropylene, polyethylene, or polyester to a sound absorbing layer made of felt, urethane foam, or the like. A formed sound absorbing material is disclosed.

  Patent Document 3 discloses a sound insulation sheet in which a nonwoven fabric is laminated between a skin material and a sound absorbing material, and all or a part of the nonwoven fabric is melted to bond them together. A laminated cushion sheet is disclosed in which a heat-adhesive nonwoven fabric or the like is interposed between a skin material and a nonwoven fabric and bonded together by heat melting. Patent Document 5 discloses an automobile interior base material in which a hot melt film or a low melting point resin non-woven fabric is laminated between a fiber layer and a thermoplastic resin sheet layer, and is laminated by heating and pressing. ing.

Further, Patent Document 6 discloses a vehicle carpet in which a sound absorbing layer made of a nonwoven fabric and a skin material layer are bonded by heating and melting thermoplastic resin powder.
JP 2003-20555 A JP 2005-263118 A JP-A-10-95059 JP 2000-248453 A JP 2005-226178 A Japanese Patent Laid-Open No. 2002-219989

  However, in the conventional method, the sound-absorbing layer and the skin are manufactured separately, and they are bonded using a thermoplastic resin powder, a heat-adhesive fiber, a resin, a nonwoven fabric, or a film, or a heat-adhesive layer. A sound-absorbing layer in which fibers are mixed is prepared, and this is melted and bonded to the outer skin, whereby both are laminated and integrated. Therefore, there are problems such as wrinkling during bonding, and when the fiber is shrunk and heated / fused at a high temperature, the laminate is deformed. In addition, when the obtained laminate is used in a place with a high temperature, the sound absorbing layer and the skin layer are peeled off due to softening or melting of the adhesive resin, so that the desired sound insulation and sound absorbing performance cannot be exhibited and the durability is lowered. There was a problem of doing. Further, in the conventional method, particularly when a material having a low elongation is used for the skin layer, the nonwoven fabric layer (sound absorbing layer) is deformed following the mold during molding, but the skin layer is broken. Further, since it is necessary to prepare a skin layer in advance and laminate and integrate it with the sound absorbing layer, there is a problem that the manufacturing process becomes complicated and the manufacturing cost increases.

  The present invention has been made in view of the above circumstances, and can simplify the manufacturing process, hardly cause heat shrinkage, deformation, wrinkles, etc., due to lamination and integration, and has sound absorption, moldability, and durability. It is an object to provide a sound-absorbing material excellent in the above.

  As a result of earnest research to solve the above-mentioned problems, the present inventors separately prepared a skin material by laminating a nonwoven fabric layer made of synthetic resin fibers using a curtain spray method on a sound absorbing layer made of nonwoven fabric. Thus, the present inventors have found that the formation of the skin layer and the lamination integration can be performed simultaneously, and the present invention has been achieved.

  That is, the present invention has a sound-absorbing material comprising a sound-absorbing layer made of a nonwoven fabric and a skin layer made of synthetic resin fibers formed by direct spraying by a hot melt spray method and deposited on the fibers of the sound-absorbing layer I will provide a.

  The present invention also provides a sound absorbing layer comprising a sound absorbing layer made of polyurethane foam and a skin layer made of synthetic resin fibers formed by direct spraying by a hot melt spray method and deposited on the fibers of the sound absorbing layer. Providing materials.

  The present invention also provides a sound absorbing material, wherein the sound absorbing material is molded.

  The present invention also provides a vehicle interior material characterized by using the above-described sound absorbing material and a sound absorbing material obtained by molding the sound absorbing material.

  In the sound-absorbing material of the present invention, the nonwoven fabric is preferably a short fiber web, and is a needle punched nonwoven fabric or an airlaid nonwoven fabric in which low melting point fibers contained in the web are blown with high temperature air and melt bonded to surrounding fibers. More preferably. The nonwoven fabric is preferably a melt blown nonwoven fabric. It is preferable that the fiber which comprises the said nonwoven fabric is a 1 type, or 2 or more types of fiber chosen from a thermoplastic fiber and a heat resistant fiber whose melting temperature or thermal decomposition temperature is 370 degreeC or more.

  The melting point of the synthetic resin is preferably 200 ° C. or less, and the melt viscosity at 200 ° C. is preferably 40000 mPa · s or less. The synthetic resin is a colorant, a flame retardant, or a water repellent. It may contain at least one kind.

  When the fibers constituting the nonwoven fabric and the fibers constituting the skin layer are composed of the same type of synthetic fibers, recycling is easy.

In the sound-absorbing material of the present invention, the air flow rate measured based on JIS L 1096 is preferably 0.01 to 50 cc / cm ² / sec. Thereby, it becomes a sound-absorbing material excellent in sound absorption.

  As described above, according to the present invention, since the manufacturing process is simplified, it is possible to provide a sound-absorbing material excellent in sound-absorbing performance and durability at a low cost, and the obtained sound-absorbing material is a conventional bonding. There are no wrinkles like products, it is supple and easy to mold. Further, according to the present invention, if a coloring material, a flame retardant, a water repellent and the like are blended with a synthetic resin, a sound absorbing material having a skin layer colored, flame retardant or water repellent, It can be manufactured in one step. Further, according to the present invention, it is possible to provide a sound absorbing material that is excellent in sound absorbing performance, moldability, and durability and excellent in recyclability.

  Furthermore, since the sound absorbing material of the present invention has the above characteristics, it can be suitably used particularly for a vehicle interior material.

  The sound-absorbing material of the present invention includes a sound-absorbing layer made of a nonwoven fabric and a skin layer made of a synthetic resin fiber that is directly sprayed and formed by hot melt spraying and is attached to the heat-adhesive fibers of the sound-absorbing layer.

  The fibers constituting the nonwoven fabric include one or more of synthetic fibers, chemical fibers such as rayon, natural fibers such as cotton, hemp, jute, wool, and anti-hairs (recovered and recycled fibers). Can be used. Of these, synthetic fibers are preferred from the viewpoints of heat resistance, wear resistance, and the like. Examples of such synthetic fibers include thermoplastic fibers such as polyester fibers, polyamide fibers, acrylic fibers, polypropylene fibers, and polyethylene fibers; aramid fibers, polyarylate fibers, polybenzoxazole (PBO) fibers, polybenzthiazole fibers, polybenzimidazole ( The melting temperature or thermal decomposition temperature of PBI) fiber, polyimide fiber, polyetherimide fiber, polyetheretherketone fiber, polyetherketone fiber, polyetherketoneketone fiber, polyamideimide fiber, flameproof fiber, etc. is 370 ° C. or higher. A heat-resistant fiber is mentioned. As these synthetic fibers, those conventionally known and those manufactured according to a known method or a method analogous thereto can be used. The flame-resistant fiber is a carbon fiber precursor mainly produced by firing acrylic fiber at 200 to 500 ° C. in an active atmosphere such as air. For example, the product name “LASTAN” (registered by Asahi Kasei Corporation) Trademark), and trade name “Pyromex” (registered trademark) manufactured by Toho Tenax Co., Ltd.

  Among the above thermoplastic fibers, polyester fibers, polypropylene fibers, and polyamide fibers are preferable from the viewpoint of excellent durability and wear resistance, and these fibers may be used alone or mixed in an arbitrary ratio. it can. Polyethylene terephthalate, polybutylene terephthalate, biodegradable polyester, especially because raw polyester can be easily recycled by heat melting of waste nonwoven fabric, and it has excellent economic efficiency, good nonwoven fabric texture, and excellent moldability. Most preferred are polyester fibers such as fibers.

  Moreover, even if it is the same material, it is preferable to mix fibers having different melting points as appropriate because the nonwoven fabric shape-forming property during heat setting and the shape retention property during molding are improved.

  Among the above heat-resistant fibers, aramid fibers, polyarylate fibers and polybenzoxazole fibers which do not melt at high temperatures are preferable from the viewpoint of low shrinkage and good processability, and aramid fibers and polybenzoxazole fibers are most preferable. It is possible to improve the durability and heat resistance of the sound-absorbing material by mixing the heat-resistant fiber with the thermoplastic fiber at an arbitrary mixing ratio, and high heat resistance is required by using only the heat-resistant fiber. A sound-absorbing material suitable for the intended use can be obtained.

  The aramid fibers include para-aramid fibers and meta-aramid fibers. Para-aramid fibers are preferred from the viewpoint of less heat shrinkage. Examples of para-aramid fibers include polyparaphenylene terephthalamide fibers (US DuPont, manufactured by Toray DuPont, trade name “KEVLAR” (registered trademark)), copolyparaphenylene-3,4′-oxydi. Commercial products such as phenylene terephthalamide fiber (manufactured by Teijin Limited, trade name “Technola” (registered trademark)) can be used.

  The fiber length and fineness of the fibers constituting the nonwoven fabric are not particularly limited, but the fiber length is preferably 10 mm or more. Filaments or staples may be used, but in the case of staples, the fiber length is preferably 10 to 100 mm, and particularly preferably 20 to 80 mm. By using short fibers having a fiber length of 10 mm or more, the tangled short fibers are less likely to fall off the nonwoven fabric. On the other hand, when the fiber length is long, the card passing property tends to be inferior. A fineness of 0.5 to 30 dtex, particularly 1.0 to 10 dtex is preferably used. The short fibers can be used alone or in combination of two or more, and the same or different fibers having different fineness and fiber length can also be mixed and used.

  Non-woven fabric constituting the sound absorbing layer is a long-fiber non-woven fabric such as a melt-blown non-woven fabric or a spunbond non-woven fabric, and an airlaid non-woven fabric, a needle punch, which is fused to the surrounding fibers by melting low-melting-point fibers in the web with hot air. A short fiber web in which short fibers are entangled by a water jet punch can be used, and miscellaneous felt can also be used as a nonwoven fabric. Among these non-woven fabrics, a short fiber web is preferable because the gap between the fibers is wide and the synthetic resin fibers constituting the skin layer are easily entangled when sprayed onto the sound absorbing layer. The web can be manufactured according to a conventional web forming method using a conventional web forming apparatus. For example, after blended short fibers are opened using a card machine, they are formed on a web. After the fibers are entangled by performing needle punching or the like, the nonwoven fabric can be obtained by drying in the same manner as in the prior art and heat setting as necessary.

The basis weight of the nonwoven fabric constituting the sound absorbing layer is preferably in the range of 150 to 2500 g / m ² . If the basis weight is too small, the shape retention of the web layer will be poor, and if the basis weight is too large, the energy required for entanglement of the fibers will increase, or the entanglement will be insufficient, resulting in inconveniences such as deformation during the production of the nonwoven fabric. If the density of the non-woven fabric is too small, the sound-absorbing property is lowered, and if it is too large, the wear resistance and workability are lowered, so the range of 0.01 to 0.2 g / cm ³ is preferable, more preferably 0.01. It is in the range of ˜0.1 g / cm ³ .

  In the sound absorbing material of the present invention, the sound absorbing layer may be made of polyurethane foam. The polyurethane foam may be either a flexible polyurethane foam or a rigid polyurethane foam. For example, a polyurethane foam molded into a sheet, or a molded product cut into a sheet can be used.

  The thicker the nonwoven fabric and the polyurethane foam, the better the sound absorption, but it is preferably 2 to 100 mm, more preferably 3 to 50 mm, from the viewpoints of economy, ease of handling, and space securing as a sound absorbing material.

  On the other hand, the skin layer is made by melting thermoplastic synthetic resin and spraying this directly onto the sound absorbing layer by the hot melt spray method so that the synthetic resin fibers are entangled with the fibers of the sound absorbing layer. ,It is formed. This hot-melt spray method is a method that uses curtain spray, which is generally used for adhesives, and is a spray nozzle in which a large number of small holes are arranged in a row from a molten resin pumped from a molten resin tank by a pump or the like. From a slit provided so as to sandwich a row of small holes, and is spun and stretched by a high-temperature and high-speed air stream, and sprayed directly onto a nonwoven fabric to be a sound absorbing layer to form a nonwoven fabric.

  In this case, it is preferable that the nonwoven fabric used as the sound absorption layer is compressed in advance with a hot roll or the like to smooth the surface, and the uneven adhesion of the fibers of the skin that is extruded from the spray nozzle and spun and stretched from the slit by a high-temperature high-speed air stream is reduced. Moreover, it is preferable to press with a hot roll or the like immediately after spraying the fibers of the skin, since the adhesion between the skin and the nonwoven fabric layer is further improved.

  FIG. 1 is a side view schematically showing a method for producing a sound absorbing material of the present invention. In FIG. 1, 1 is a resin coating line, 2 is a sound absorbing layer (nonwoven fabric), 3 is a molten resin, R is a molten resin flow, 4 is a pressurized air, and A is a pressurized heated air flow. 5 is decorated. While moving the coating line 1 in the direction of the arrow, a molten resin flow and a heated and pressurized air flow are sprayed to form a skin layer made of molten resin fibers on the sound absorbing layer.

  The synthetic resin is not particularly limited as long as it is a meltable resin. For example, polyester resin, polyamide resin, acrylic resin, polyethylene resin, polypropylene resin, ethylene-vinyl acetate resin, polyester polyol resin, ethylene propylene copolymer resin, Examples thereof include polyester copolymer resins. Among these synthetic resins, a synthetic resin having a melting point of 200 ° C. or lower, more preferably a melting point of 150 ° C. or lower is preferably used from the viewpoint of excellent dischargeability during spraying. In addition, a resin having a low melt viscosity, for example, a polyethylene resin, a polypropylene resin, a polyester copolymer resin, or the like is preferably used.

0.1-100 micrometers is preferable and, as for the average fiber diameter of the synthetic resin fiber which comprises a skin layer, 1-50 micrometers is more preferable. The basis weight of the skin layer is preferably in the range of 10 to ²⁰⁰ g / m2.

The sound-absorbing material of the present invention has an air flow rate measured in accordance with JIS L 1096 of 0.01 to 50 cc / cm ² / sec, preferably 0.05 to 30 cc / cm ² / sec. If the air flow rate is less than 0.01 cc / cm ² / sec, the permeability of gas such as engine gas is low, and if it exceeds 50 cc / cm ² / sec, the sound absorption performance is deteriorated.

  When the synthetic resin fiber constituting the skin layer and the fiber constituting the nonwoven fabric of the sound absorbing layer are made of the same material, recycling becomes easy. That is, for example, a large amount of a sound absorbing material used as a vehicle interior material for an automobile or the like is required and must be recyclable. Therefore, if different materials are used, it will be necessary to disassemble and it will be difficult to recycle.

  The sound-absorbing material of the present invention can be further closely attached to a site where the sound-absorbing material is required by further molding. Molding is performed by heating a sound-absorbing material that has been used in the past, placing it in a mold, hot pressing and then cooling, or heating and then placing it in a male or female mold, and then using a vacuum device to male or female. Vacuum forming or the like in which the mold is brought into close contact with the mold and cooled may be used. Moreover, the method of shape | molding, applying a heat | fever from a vacuum bag during a driving | operation of a vacuum pump may be used. The molding temperature is appropriately determined in consideration of the melting point of the sound absorbing material.

  Moreover, you may mix | blend at least 1 sort (s) of a coloring material, a flame retardant, and a water repellent with a conventionally well-known compounding quantity with the synthetic resin which comprises a skin layer. Examples of the colorant include known colorants such as pigments and dyes. Examples of the flame retardant include known flame retardants such as phosphate esters, halogens, and hydrated metal compounds. Known water and oil repellents such as fluorine and silicone can be used.

  When the sound absorbing material of the present invention is used, one layer or two or more layers of air permeable film, paper, woven fabric, knitted fabric or the like may be laminated on one side or both sides.

  The sound-absorbing material of the present invention is preferably applied to automotive interior materials such as automobile ceiling materials, floor materials, option mats, rear packages, door trims, etc. by laminating a surface layer material or the like normally used for automotive interior materials on this. can do. The surface layer material is preferably laminated on the skin layer side so as not to impair the water repellency, water resistance and sound absorption properties of the sound absorbing material. When a surface layer material is laminated on the skin layer, the surface layer material may be laminated directly on the skin layer, or may be laminated via another layer (for example, a gray layer).

  Examples of the surface layer material include non-woven fabric, woven fabric, moquette, tricot, jersey, carpet, leather, artificial leather, and synthetic resin sheet.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited only to a following example. In addition, the measuring method of each characteristic value in the following examples and comparative examples is as follows.

[Air flow rate]
Based on the fragile method of JIS L-1096, measurement was performed in a state where a skin layer was laminated on a non-woven fabric using FX3300 manufactured by TEXTEST, Switzerland.

Further, the reverberation room sound absorption coefficient was measured at a sample area of 5.0 m ² using a steady sound pressure generator ME-RE3300 (Matsushita Intertechno Co., Ltd.) and a YS7046 type sound intensity measuring apparatus of Fukui Industrial Test Center.

[Sound absorption rate]
Using an automatic normal incidence sound absorption measurement device (manufactured by Sotec Co., Ltd.), the normal incidence sound absorption coefficient at each frequency was measured according to JIS-A-1405 “Method for measuring normal incidence sound absorption coefficient of building material in pipe method”. The measurement was performed with the sound absorbing material attached so that the skin layer was on the sound source side.

Example 1
70% polyethylene terephthalate staples (1.7 dtex x 51 mm) manufactured by Toray Industries, Inc. and 30% “Safmet” with a melting point of 110 ° C. are mixed and opened. After the carding process, needle punching is performed at 150 ° C. for 3 minutes. A heat-treated polyester nonwoven fabric having a thickness of 10 mm and a basis weight of 400 g / m ² was produced (density: 0.04 g / cm ³ ).

  A copolymer polyester resin having a melting point of 120 ° C. (viscosity at 190 ° C. is 30000 mPa · s) on the above-mentioned nonwoven fabric, a molten resin temperature of 155 ° C., a spray head temperature of 160 ° C., a hot air temperature of 160 ° C., and a distance between the nonwoven fabric and the nozzle of 80 mm The skin layer was formed by coating under the above conditions. The coating amount was changed by the amount shown in Table 1, and the air permeability and sound absorption (vertical incidence) of the sound absorbing material at that time were measured.

(Reference example)
On the surface of a commercially available polyester paper (thickness 98 μm, basis weight 43 g / m ² ), an ethylene-vinyl acetate copolymer powder (Tokyo Ink Co., Ltd., 2030-M) was applied (10 g / m ² ), The polyethylene terephthalate nonwoven fabric produced in Example 1 was placed on this surface and bonded together in a heating furnace (135 ° C. × 1 minute) to produce a sound absorbing material.

  Table 1 shows the air permeability of the sound-absorbing materials produced in the examples and reference examples.

The normal incidence sound absorption coefficient of the sound absorbing material of Example 1 coating amount of 30 g / m 2 was produced by, ^{60 g} / m ^2, combined with sound absorption properties of the reference example, as shown in FIG. As is clear from this result, the sound absorbing material of the present invention had a sound absorbing property comparable to that obtained by bonding polyester paper.

  Further, the sound absorbing material of the present invention had a flexible surface and was not wrinkled as when polyester paper was bonded.

Moreover, the reverberation chamber sound absorption coefficient of the sample with the coating amount of 60 g / m ² (aeration amount of 10.8 cc / cm ² / sec) was measured. As this reference product, the one using the polyester paper of the reference example for the skin was measured. The results are shown in FIG.

(Example 2)
A nonwoven fabric having a thickness of 20 mm and a weight per unit area of 800 g / m ² is produced by the needle punch method using the same fiber as in Example 1 (density 0.04 g / cm ³ ), and then copolymerized under the same conditions as in Example 1. A polyester resin was applied to form a skin layer. At this time, the air permeability of the laminate of the skin layer and the nonwoven fabric was 9.5 cc / cm ² / sec. The reverberation chamber sound absorption coefficient measurement results are shown in FIG.

  As is apparent from the results of FIGS. 2 and 3, it can be seen that the sound-absorbing material of the present invention exhibits good sound-absorbing and insulating characteristics by increasing the coating amount.

  Cover the sound absorbing material created in Example 1 on a male mold, cover it with a vacuum bag made of silicone sheet, and keep the sound absorbing material and the mold in close contact with each other while sucking air with a vacuum pump. In this state, infrared lamp light was irradiated from the outside of the vacuum bag to mold, cooled for 10 minutes, and then taken out from the vacuum bag to obtain a molded product. The molded product was neither wrinkled nor torn in the skin portion and the nonwoven fabric portion, and the shape retention was good.

  The sound-absorbing material of the present invention can be used in various applications where sound-absorbing properties are required by processing it into an appropriate size, shape, etc. by applying a known method according to the purpose and application. Insulators for automobiles, trains, aircraft interior dashboards, automobiles, trains, aircraft and other dashboards; electrical appliances such as refrigerators, vacuum cleaners and air conditioners; speaker diaphragms; lawn mowers It can be used in various applications such as electric tools such as electric drills and electric excavators, and wall materials for civil engineering and construction.

It is a side view which shows roughly the manufacturing method of the sound-absorbing material of this invention. It is a graph which shows the sound absorption characteristic of the sound-absorbing material of this invention. It is a graph which shows the reverberation room sound absorption rate of the sound-absorbing material of this invention.

Explanation of symbols

1 Resin coating line 2 Sound absorbing layer (nonwoven fabric)
3 Molten resin 4 Pressurized air 5 Heater R Molten resin flow A Pressurized heated air flow

Claims (13)

A sound absorbing layer made of non-woven fabric;
A sound-absorbing material comprising a skin layer made of synthetic resin fibers formed by direct spraying using a hot melt spray method and attached to the fibers of the sound-absorbing layer. The sound absorbing material according to claim 1, wherein the nonwoven fabric is a short fiber web. The sound absorbing material according to claim 1, wherein the nonwoven fabric is a needle punched nonwoven fabric. The sound absorbing material according to claim 1, wherein the nonwoven fabric is an airlaid nonwoven fabric. The sound absorbing material according to claim 1, wherein the nonwoven fabric is a meltblown nonwoven fabric. The fiber which comprises the said nonwoven fabric is a 1 type, or 2 or more types of fiber chosen from a thermoplastic fiber, a heat-resistant fiber whose melting temperature or thermal decomposition temperature is 370 degreeC or more, Any one of Claims 1-5 The sound absorbing material described. A sound absorbing layer made of polyurethane foam;
A sound-absorbing material comprising a skin layer made of synthetic resin fibers formed by direct spraying using a hot melt spray method and attached to the fibers of the sound-absorbing layer. The sound-absorbing material according to claim 1, wherein the synthetic resin has a melting point of 200 ° C. or less and a melt viscosity at 200 ° C. of 40000 mPa · s or less. The sound-absorbing material according to any one of claims 1 to 8, wherein the synthetic resin contains at least one of a colorant, a flame retardant, and a water repellent. The sound-absorbing material according to any one of claims 1 to 9, wherein the fibers constituting the nonwoven fabric and the fibers constituting the skin layer are composed of the same type of synthetic fibers. The sound-absorbing material according to any one of claims 1 to 10, wherein an air flow rate measured based on JIS L 1096 is 0.01 to 50 cc / cm ² / sec. A sound-absorbing material obtained by molding the sound-absorbing material according to claim 1. An interior material for a vehicle, wherein the sound absorbing material according to any one of claims 1 to 12 is used.

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