JP2006321053A - Heat-resistant sound-absorbing and heat insulating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-resistant sound-absorbing and heat insulating material having no concern of the falling-off or pyrolysis of fibers and excellent in sound absorbing properties and heat insulating properties even if installed at a place where a temperature becomes 400-450°C such as a car muffler or the like. <P>SOLUTION: The heat-resistant sound-absorbing and heat insulating material is constituted by laminating a needle punched nonwoven fabric, which is obtained by the needle punching of short fibers comprising a heat-resistant organic fiber such as an aramid fiber or a PBO fiber, on a sheetlike heat-resistant member containing high purity silica-alumina ceramic fibers and inorganic particles. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat-resistant sound-absorbing heat insulating material, and particularly to a sheet-shaped heat-resistant sound-absorbing heat insulating material suitable for silencing a four-wheel or two-wheel automobile muffler.

  Generally, in a four-wheeled vehicle and a two-wheeled vehicle, a sound absorbing / sound insulating material is used to mute the sound generated from the internal combustion engine. In the vicinity of the exhaust muffler, the temperature may be considerably high under conditions of high load during climbing and high rotation speed during high-speed traveling. Conventionally, glass wool or stainless wool has been proposed as a sound absorbing material, but glass wool may scatter in the atmosphere and lead to air pollution, while stainless wool has a shape retention property when it is needled. Inferior to

  Therefore, a heat-resistant sound-absorbing material in which inorganic fibers such as rock wool are hardened with a phenol resin is used as a sound-absorbing material and the high-temperature contact surface side is covered with a perforated metal plate has been proposed (Patent Document 1, etc.). However, since the heat resistance of the phenol resin is inferior, there is a problem that the inorganic fibers are gradually separated over time and the sound absorption performance is lowered.

In addition, as a sound absorbing material that can be applied to a part having an exhaust temperature of about 800 ° C. in a four-wheeled vehicle or a two-wheeled vehicle, it is proposed that a sheet obtained by needle punching a stainless steel fiber is covered with a porous pipe constituting an automobile muffler. (Patent Document 2). However, as described above, the stainless steel fiber has a problem that shape retention is poor when it is needled, the entanglement of the fiber is loosened over time, and the fiber falls off.
Japanese Patent Laid-Open No. 1-211608 Japanese Patent Laid-Open No. 8-100267

  The present invention has been made in view of the above-described conventional problems, and there is no risk of fiber dropping or thermal decomposition even when installed in a place where the temperature is 400 to 450 ° C., such as an automobile muffler. And it aims at providing the heat-resistant sound-absorbing heat insulating material which is excellent in sound-absorbing property and heat insulation.

  As a result of intensive studies to achieve the above object, the inventors of the present invention are composed of a low-breathing sheet-like nonwoven fabric containing ceramic fibers and inorganic particles, composed of short fibers of one or more types of heat-resistant organic fibers. By laminating needle punched nonwoven fabrics with high air permeability, heat dissipation is promoted and heat insulation is improved, and sound absorbing properties (especially in the low frequency region) are higher than when the nonwoven fabrics are used alone. It has been found that the sound-absorbing and heat-insulating material can be reduced in weight significantly, and has reached the present invention.

That is, the present invention is as follows.
1) A needle punched nonwoven fabric obtained by needle punching one or two or more kinds of heat-resistant organic fiber short fibers is laminated on a sheet-like heat-resistant member containing ceramic short fibers and inorganic particles. Heat-resistant sound-absorbing heat insulating material,
2) The heat-resistant sound-absorbing heat insulating material according to 1) above, wherein the air permeability of the needle punched nonwoven fabric in the heat-resistant sound-absorbing heat insulating material is larger than the air permeability of the heat-resistant member,
3) The heat-resistant sound-absorbing heat insulating material according to 1) or 2), wherein the heat-resistant member has a thickness of 50 mm or less and a density in a range of 0.05 to 0.5 g / cm ^3. ,
4) The needle punched nonwoven fabric has a thickness of 3 to 50 mm and a density in the range of 0.01 to 0.1 g / cm ³ . Heat-resistant sound-absorbing heat insulating material,
5) The heat-resistant organic fiber is at least one fiber selected from the group consisting of an aramid fiber, a polybenzoxazole fiber, a polyarylate fiber, and a polyimide fiber, any one of the above 1) to 4) Heat-resistant sound-absorbing heat insulating material as described in
6) The heat-resistant sound-absorbing heat insulating material according to any one of 1) to 5), wherein the ceramic fiber is a silica-alumina fiber, an alumina fiber, or a mullite fiber,
7) The heat-resistant sound-absorbing heat insulating material according to any one of 1) to 6) above, wherein the inorganic particles are alumina particles.
8) The heat-resistant sound-absorbing heat-insulating material according to any one of 1) to 7), wherein the heat-resistant member has a structure in which ceramic short fibers are bonded with an organic or inorganic binder, and
9) The heat-resistant sound-absorbing heat insulating material according to any one of 1) to 8), wherein the heat-resistant member is disposed on a sound source side.

  According to the present invention, a heat-resistant member containing ceramic short fibers and inorganic particles is laminated with a needle punched nonwoven fabric made of heat-resistant organic fibers and having excellent heat resistance and air permeability, and is lightweight and heat-insulating. It is possible to provide a heat-resistant sound-absorbing heat insulating material having excellent properties and sound-absorbing properties. Moreover, since the needle punched nonwoven fabric is laminated, the handleability is excellent without the ceramic fibers or the like falling off from the heat-resistant member. Since the heat-resistant sound-absorbing heat insulating material of the present invention exhibits stable sound-absorbing performance without thermal deterioration even at high temperatures of 400 to 450 ° C., it can be used as a sound-absorbing material for exhaust mufflers of four-wheeled vehicles and two-wheeled vehicles. The noise outside the vehicle can be greatly reduced.

  Moreover, since the heat-resistant sound-absorbing heat insulating material of the present invention is excellent in sound insulation, flame retardancy, and mechanical strength in addition to the above effects, as a heat-resistant cushioning material, heat-resistant sealing material, heat-resistant conveying belt, etc. It can also be used for heat insulation and sound absorption around lighting devices, wall materials, and various pipes.

  The heat-resistant member used in the heat-resistant sound-absorbing heat insulating material of the present invention contains ceramic short fibers and inorganic particles as essential components. Furthermore, it may contain inorganic fibers such as asbestos, glass fibers and silica fibers, and short fibers such as carbon fibers and metal fibers. However, asbestos and glass fibers do not cause the generation of harmful gases during combustion and are insulated. This is also advantageous in terms of the properties and sound absorption. The heat-resistant member has a structure in which ceramic short fibers and inorganic particles are bonded with an inorganic binder, or a molded body in which ceramic fibers and inorganic particles are bonded with an organic binder is dried and fired. Is exemplified. These heat resistant members are obtained by the method described in paragraphs [0033] to [0046] of JP-A-2002-284567.

  As the ceramic fiber, conventionally known various ceramic fibers can be used, for example, chopped strands obtained by fiberizing refined alumina / silica mineral as a main raw material, and whisker, etc. It is done. Examples of chopped strands include silica-alumina fibers, alumina fibers, mullite fibers, and the like. Examples of the whisker include aluminum borate whisker, potassium titanate whisker, silicon carbide whisker, zinc oxide whisker, and alumina whisker.

  Of these, high alumina silica-alumina fibers, alumina fibers, and mullite fibers having an alumina content of 70% by mass or more are preferable because of their good heat resistance.

  Moreover, as an inorganic particle, an alumina particle is preferable. Among these, high alumina particles having an alumina content exceeding 70% by mass are preferable.

  Moreover, as said inorganic binder, colloidal silica and an alumina sol are preferable.

  In order to produce a heat-resistant member, first, a slurry obtained by adding and mixing water and an organic binder (for example, starch) to the above raw material is molded by a suction dehydration molding method to obtain a plate-shaped molded body. A heat-resistant member is obtained by drying the molded body. In this state, ceramic fibers and inorganic particles are bonded to each other by an intermolecular force between the organic binder and colloidal silica to form a molded body. Although it can be used as a heat-resistant member even in this state, it may be further fired to obtain a fired product. Firing may be performed at a temperature of 800 to 1500 ° C. for 1 hour to 5 hours. In the fired product, colloidal silica and an alumina component react to form mullite, and are bonded by mullite quality. When the organic binder is volatilized by heating at the time of use, it is preferable to calcinate in advance and remove the organic binder.

The heat-resistant member thus obtained preferably has a thickness of 50 mm or less, more preferably 1 to 40 mm, still more preferably 1 to 30 mm. The density of the heat-resistant member is in the range of 0.05 to 0.5 g / cm ³ . The thicker the heat-resistant member, the better the sound absorption and heat insulation properties, but against the weight reduction, the handleability when wound around a muffler or the like deteriorates. On the other hand, if the heat-resistant member is too thin, the sound absorption in the low frequency region is lowered.

  The heat-resistant organic fiber used in the heat-resistant sound-absorbing heat insulating material of the present invention is preferably a fiber having a melting temperature or a thermal decomposition temperature of 370 ° C. or higher. Examples of the heat-resistant organic fibers include aramid fibers, polyarylate fibers, polybenzoxazole (PBO) fibers, polybenzthiazole fibers, polybenzimidazole (PBI) fibers, polyimide fibers, polyetherimide fibers, and polyetheretherketone. One type or two or more types of fibers selected from fiber, polyetherketone fiber, polyetherketoneketone fiber, polyamideimide fiber, and flameproof fiber can be used. As these heat-resistant organic fibers, any conventionally known fibers, those manufactured according to a known method or a method analogous thereto can be used.

  The cross-sectional shape of the heat-resistant organic fiber is not particularly limited, and may be a perfect circular cross-sectional shape or an irregular cross-sectional shape. For example, elliptical shape, hollow shape, X sectional shape, Y sectional shape, T sectional shape, L sectional shape, star sectional shape, leaf shaped sectional shape (for example, three leaf shape, four leaf shape, five leaf shape, etc.), other polygonal sectional shape (For example, a triangular shape, a square shape, a pentagonal shape, a hexagonal shape, etc.) may be used.

  Among the above heat-resistant organic fibers, aramid fibers, polyarylate fibers, polybenzoxazole (PBO) fibers and polyimide fibers, which are low shrinkage, good workability and do not melt at high temperatures, are preferred, and more preferred are aramid fibers. Polybenzoxazole (PBO) fiber.

  Aramid fibers include para-aramid fibers and meta-aramid fibers. Examples of para-aramid fibers include polyparaphenylene terephthalamide fibers (manufactured by DuPont, Inc., Toray DuPont, trade name “KEVLAR”). ”(Registered trademark)), copolyparaphenylene-3,4′-oxydiphenylene terephthalamide fiber (manufactured by Teijin Ltd., trade name“ Technola ”(registered trademark)) and the like. Metaphenylene isophthalamide fiber (trade name “NOMEX (registered trademark)” manufactured by DuPont, USA, trade name “Conex (registered trademark)” manufactured by Teijin Limited), and the like. Among these aramid fibers, para-aramid fibers are preferable from the viewpoint of excellent heat resistance.

  The aramid fiber may be provided with a film former, a silane coupling agent, and a surfactant on the fiber surface and inside the fiber as necessary. The solid content of these surface treatment agents on the aramid fibers is preferably in the range of 0.01 to 20% by mass.

  As the nonwoven fabric composed of one or more heat-resistant organic fibers, a needle punched nonwoven fabric obtained by needle-punching short fibers of heat-resistant organic fibers by a conventionally known method is used. Since the needle punched nonwoven fabric has high air permeability, it has good heat insulation, excellent sound absorption, and low density. Therefore, the weight of the sound absorption heat insulating material can be reduced without impairing sound absorption performance. The needle punched nonwoven fabric may be used in at least one layer, and a laminate of these may be used.

  The fiber length and fineness of the short fibers are not particularly limited, and can be appropriately determined depending on processability, sound absorption characteristics, and the like. The fineness of the short fibers is usually 0.5 to 30 dtex, preferably 1.0 to 20 dtex, more preferably 1.0 to 10 dtex. The fiber length of the short fibers is 10 to 100 mm, particularly preferably 20 to 80 mm. The heat-resistant organic fibers may be the same type or different types of fibers and may be used by mixing fibers having different fineness and fiber length. In this case, the mixing ratio of the fibers is arbitrary, and can be appropriately determined according to the use and purpose.

The needle punched nonwoven fabric preferably has a density in the range of 0.01 to 0.1 g / cm ³ from the viewpoint of sound absorption performance and heat insulation. If the density is too small, the sound absorption and heat insulation properties decrease, and if it is too large, the wear resistance and workability deteriorate. More preferably, it is the range of 0.02-0.08 g / cm < ³ >. In this way, by controlling the density of the non-woven fabric laminated on the heat-resistant member with low air permeability and increasing the air permeability, heat release from the heat source is promoted, and as a result, excellent heat insulation performance is imparted to the sound-absorbing heat insulating material. can do.

  In the present invention, the thicker the nonwoven fabric, the better the sound absorbing performance, but it is preferably about 3 to 50 mm, more preferably 5 to 30 mm from the viewpoints of economy, ease of handling, and securing of space as a sound absorbing material.

  The nonwoven fabric used in the heat-resistant sound-absorbing heat-insulating material of the present invention is an integral product obtained by interlacing a web made of short fibers of heat-resistant organic fibers by a needle punch method. By performing the needle punching treatment, the short fibers of the web can be entangled to prevent the short fibers from falling off. In addition, while having an appropriate air permeability, the ceramic short fibers etc. can be removed from the heat-resistant member. The nonwoven fabric which can be prevented can be manufactured easily.

The needle punching process may be performed on either one side or both sides of the web. If the punching density is too low, the entanglement of the short fibers becomes insufficient, and if it is too high, the air permeability of the nonwoven fabric decreases and the heat insulating effect and the sound absorbing effect are impaired. Therefore, about 50 to 300 times / cm ² is preferable. more preferably from 50 to 100 times / cm ^2.

  In the present invention, the needle punching process can be performed according to a conventional needle punching method using a needle punching apparatus similar to the conventional one.

  The heat-resistant member and the nonwoven fabric may be laminated in a non-adhered state, but are preferably bonded and laminated in order to prevent a decrease in sound absorption performance due to peeling of the sound absorbing material. Lamination of heat-resistant material and non-woven fabric is done by stitching, needle punching, etc. in a method that does not use an adhesive, and after a metal fitting with a base is passed through the skin material and composite fiber structure, another perforated metal is attached to the tip. It is also possible to employ a method of passing the plate and bending the tip of the metal joint with the base to join. Moreover, the method of attaching a fixing member using a binding machine can also be employed, and examples thereof include Bannock Pin (registered trademark) (manufactured by Bannock Japan).

  In the heat-resistant sound-absorbing heat insulating material of the present invention, it is preferable that the heat-resistant member is disposed on the sound source (muffler or the like) side from the viewpoint that excellent sound absorbing properties and heat insulating properties can be exhibited. 1 is a schematic cross-sectional view (FIG. 1 (a)) showing an embodiment when a heat-resistant sound-absorbing heat insulating material 1 is wound around an automobile muffler 2 and a partially enlarged cross-sectional view in a circle (FIG. 1 (b)). )). In FIG. 1, 11 is a heat-resistant member and 12 is a nonwoven fabric. The heat-resistant sound-absorbing heat insulating material can be attached with the heat-resistant member 11 facing the muffler and a non-woven fabric is arranged on the outside, thereby suppressing the short fibers and inorganic particles constituting the heat-resistant member from falling off. Moreover, you may interpose papers (aramid paper etc.) formed from said heat resistant organic fiber between a heat resistant member and a nonwoven fabric.

  The heat-resistant sound-absorbing heat insulating material of the present invention may be colored with a dye or a pigment as necessary. As a coloring method, an original yarn obtained by spinning a dye or pigment mixed with a polymer before spinning may be used, or fibers colored by various methods may be used. The heat-resistant sound-absorbing heat insulating material may be colored with a dye or pigment.

  The heat-resistant sound-absorbing heat insulating material of the present invention can be used for various purposes by applying a known method or the like according to its purpose and use, and processing it into an appropriate size, shape, etc. It can be used for all applications that require sound absorption and heat insulation.

  For example, noise reduction and sound insulation of internal combustion engines such as automobiles, trains, wagons, ships, and aircraft; electric vacuum cleaners, ventilation fans, electric washing machines, electric refrigerators, freezers, electric clothes dryers, electric mixers / juicers, air conditioners (air conditioners) , Hair dryers, electric razors, air cleaners, electric dehumidifiers, electric lawn mowers, etc., silencing and sound insulation; lighting equipment silencing and sound insulation; building wall materials; around various pipes; breakers (casing lining) Etc.). In particular, noise can be greatly reduced by using it as a sound-absorbing heat insulating material for engine rooms and exhaust mufflers of two-wheeled vehicles and four-wheeled vehicles that require heat resistance and sound absorbing performance at high temperatures.

  Furthermore, the heat-resistant sound-absorbing heat insulating material according to the present invention can be used for example by a slight vibration of the sample fixing table or the instrument itself due to air vibration in a measurement chamber in a stylus microscope or an electron microscope for observing a very fine sample. Even when observation and photography are difficult, the sound insulation and sound absorption performance is excellent, and a great effect can be exhibited.

  Further, with regard to sound insulation and sound absorption of compressor and air pump sound, a large sound absorption effect can be obtained by using a heat-resistant sound-absorbing heat insulating material together with a metal BOX to be put on the pump.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to only the following Examples. In addition, the measuring method of each characteristic value in the following examples and comparative examples is as follows.

[Sound absorption]
According to JIS A 1409 “Measurement method of sound absorption coefficient of reverberation room method”, reverberation room volume 38.9 m ³ , surface area 68.3 m ² , sample area using reverberation room method sound absorption coefficient measurement device installed at Fukui Industrial Technology Center. Tested at 5.0 m ² . The sound absorption was evaluated as follows with the sound absorption rate at 500 Hz.
◎: 80% or more ○: 50% or more △: Less than 50%

[Thermal insulation properties]
The created sound absorbing heat insulating material was attached to a thermal plate having a temperature of 350 to 450 ° C. so that the heat insulating member was on the thermal plate side, and the thermal insulation was evaluated by measuring the distance from the thermal plate and the temperature at that point. .

[Sound insulation]
In accordance with JIS A 1416 “Measurement method of air sound insulation performance of building materials in the laboratory”, using the transmission loss measuring device installed at Fukui Industrial Technology Center, the volume on the sound source side (reverberation room) is 38.9 m ³ , surface area 68 .3 m ² , anechoic chamber (sound receiving chamber) side laboratory volume 159.0 m ³ , surface area 177.0 m ² , sample area 0.8 m × 0.8 m = 0.64 m ² . The sound insulation was evaluated as follows by transmission loss at 5000 Hz.
◎: 50 dB or more ○: 25 dB or more Δ: Less than 25 dB

[Handling]
The presence or absence of falling off of the ceramic fibers during the handling of the sound-absorbing heat insulating material was evaluated.

[thickness]
Using a compression hardness tester (manufactured by Daiei Kagaku Seiki Seisakusho Co., Ltd.), the thickness when the load was 0.1 g / cm ² was measured.

[Air flow rate]
It measured based on the fragile method of JIS L-1096.

Example 1
Using KEVLAR (registered trademark) staple (1.5 dtex × 51 mm) manufactured by Toray DuPont Co., Ltd., a thickness of 11.5 mm, a basis weight of 510 g / m ² , and a density of 0.044 g / cm ³ by a normal needle punch method A KEVLAR nonwoven fabric was prepared.
A high-purity silica-alumina heat insulating member (“Fine Flex Blanket” manufactured by NICHIAS Corporation) having a thickness of 12.5 mm, a basis weight of 1594 g / m ² , and a density of 0.123 g / cm ³ is laminated on this nonwoven fabric, and the nonwoven fabric and the heat-resistant member Are combined with a metal pin to obtain a sound-absorbing heat insulating material.

(Example 2)
KEVLAR (registered trademark) 100% paper having a thickness of 90 μm, a weight per unit area of 57 g / m ² , and an air flow rate of 16 cc / cm ² / sec was interposed between the nonwoven fabric and the heat insulating member used in Example 1, and these were used in Example 1. The sound absorbing and heat insulating material was obtained by laminating and integrating in the same manner.

(Example 3)
On the KEVLAR nonwoven fabric prepared in Example 1, a high-purity silica-alumina-based heat insulating member ("Fine Flex Blanket" manufactured by NICHIAS Corporation) having a thickness of 25 mm, a basis weight of 3322 g / m ² , and a density of 0.123 g / cm ³ is laminated, The nonwoven fabric and the heat-resistant member were bonded together by metal pins to obtain a sound-absorbing heat insulating material.

Example 4
The same KEVLAR (registered trademark) 100% paper used in Example 2 is interposed between the nonwoven fabric used in Example 3 and the heat insulating member, and these are laminated and integrated in the same manner as in Example 3 to absorb sound. Insulation was obtained.

(Comparative Example 1)
Using the KEVLAR (registered trademark) staple (1.5 dtex, × 51 mm) manufactured by Toray DuPont Co., Ltd. used in Example 1, a thickness of 11. A KEVLER nonwoven fabric having a diameter of 5 mm, a basis weight of 510 g / m ² and a density of 0.044 g / cm ³ was obtained. The nonwoven fabric 100% KEVLAR (registered trademark) used in Example 2 was laminated and integrated in the same manner as in Example 1 to obtain a sound-absorbing heat insulating material.

(Comparative Example 2)
Using the KEVLAR (registered trademark) staple (1.5 dtex, x 51 mm) manufactured by Toray DuPont Co., Ltd. used in Example 1, the thickness was created by a normal needle punch method under the same conditions as in Example 1. A KEVLER nonwoven fabric having a thickness of 11.5 mm, a basis weight of 510 g / m ² and a density of 0.044 g / cm ³ was used.

(Comparative Example 3)
A high-purity silica-alumina heat insulating member (“Fine Flex Blanket” manufactured by NICHIAS Corporation) having a thickness of 12.5 mm, a basis weight of 1594 g / m ² and a density of 0.123 g / cm ³ was used.

(Comparative Example 4)
A high-purity silica-alumina heat insulating member (“Fine Flex Blanket” manufactured by NICHIAS Corporation) having a thickness of 25 mm, a basis weight of 3322 g / m ² , and a density of 0.123 g / cm ³ was used.

  About the sound-absorbing heat insulating material of Examples 1-4 and Comparative Examples 1-4, performance evaluation was performed according to said evaluation method. The results are shown in Table 1 together with the characteristic values of the sound absorbing heat insulating material. In addition, FIG. 2 shows the sound absorption characteristics (sound absorption coefficient of the reverberation chamber) and FIG. 3 shows the sound insulation characteristics (transmission loss) of each sound absorbing heat insulating material.

  From the results of Table 1 and FIG. 2, the sound-absorbing heat insulating material of the present invention has good handleability without falling off of the ceramic fibers, is excellent in lightness, heat insulating property and sound absorbing property, and particularly excellent in sound absorbing property in a low frequency region. . On the other hand, although the sound-absorbing heat insulating materials of Comparative Examples 1 and 2 were light and easy to handle, the sound absorbing properties and heat insulating properties were inferior. The sound absorbing heat insulating material of Comparative Example 3 was inferior in sound absorbing properties, and the sound absorbing heat insulating material of Comparative Example 4 having an increased thickness had good sound absorbing properties and heat insulating properties, but lacked handling properties.

  From the results of FIG. 3, it was confirmed that the sound-absorbing heat insulating material of the present invention was excellent in sound insulation, but that even better transmission loss was obtained by bonding to an iron plate.

  Table 2 shows the results of measuring the distance from the hot plate and its point temperature by attaching the sound-absorbing heat insulating material created in Example 3 to the hot plate.

  From the results shown in Table 2, it was confirmed that the sound absorbing heat insulating material of the present invention had a sufficiently reduced surface temperature of the outermost nonwoven fabric even when attached to a hot plate, and was excellent in heat insulating properties.

It is a schematic sectional drawing which shows the usage example to the muffler of the heat-resistant sound-absorbing heat insulating material of this invention. It is a graph which shows a sound absorption characteristic (reverberation room sound absorption rate). It is a graph which shows a sound insulation characteristic (transmission loss).

Claims (9)

A needle punched nonwoven fabric obtained by needle punching one or two or more kinds of heat-resistant organic fiber short fibers is laminated on a sheet-like heat-resistant member containing ceramic short fibers and inorganic particles. Heat-resistant sound-absorbing heat insulating material. The heat-resistant sound-absorbing heat insulating material according to claim 1, wherein the air permeability of the needle punched nonwoven fabric in the heat-resistant sound-absorbing heat insulating material is larger than the air permeability of the heat-resistant member. The heat-resistant sound-absorbing heat insulating material according to claim 1 or 2, wherein the heat-resistant member has a thickness of 50 mm or less and a density in a range of 0.05 to 0.5 g / cm ³ . The heat-resistant sound-absorbing sound according to any one of claims 1 to 3, wherein the needle punched nonwoven fabric has a thickness of 3 to 50 mm and a density of 0.01 to 0.1 g / cm ^3. Insulation. The heat-resistant organic fiber is at least one fiber selected from the group consisting of an aramid fiber, a polybenzoxazole fiber, a polyarylate fiber, and a polyimide fiber, according to any one of claims 1 to 4. Heat-resistant sound insulation. The heat-resistant sound-absorbing heat insulating material according to any one of claims 1 to 5, wherein the ceramic fiber is a silica-alumina fiber, an alumina fiber, or a mullite fiber. The heat-resistant sound-absorbing heat insulating material according to any one of claims 1 to 6, wherein the inorganic particles are alumina particles. The heat-resistant sound-absorbing heat-insulating material according to any one of claims 1 to 7, wherein the heat-resistant member has a structure in which ceramic short fibers are bonded with an organic or inorganic binder. The heat-resistant sound-absorbing heat insulating material according to any one of claims 1 to 8, wherein the heat-resistant member is disposed on a sound source side.

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