JP2021089329A - Sound insulation structure and method of manufacturing the same - Google Patents

Abstract

To provide a sound insulation structure that has high sound insulation performance even in a gamut that a human has high auditory sensitivity to, and a method of manufacturing the same.SOLUTION: A sound insulation structure 1 comprises a plate material 10, and a plurality of core materials 20, 20, ..., which is arranged on a sound insulation surface 11 of the plate material 10 adjacently to one another. The core material 20 is formed of a rectangular thin plate material 21 which is formed in a cylindrical shape, and also has one axial end joined to the sound insulation surface 11 of the plate material 10, and the adjacent core materials 20, 20 can have their side wall parts 22 made slidable on each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sound insulation structure and a method for manufacturing the same.

Conventionally, a structure having sound insulation ability has been required in the fields of construction and railways, and a structure having such ability has a space having an opening in the direction of a sound source and insulates sound in the space. It has been known. As a thing that forms a space having an opening, for example, a tubular so-called honeycomb core as shown in Patent Documents 1 and 2 is known.

Japanese Unexamined Patent Publication No. 5-92441 Japanese Unexamined Patent Publication No. 2005-307437

By the way, human beings are sensitive to sounds having a frequency of 2000 to 5000 Hz, and high sound insulation performance is required for the sound range of this frequency. Patent Document 1 does not describe the frequency, and Patent Document 2 discloses that the sound insulation performance is improved at a frequency lower than the frequency range. That is, in the sound insulation plate of Patent Document 1 and the sound insulation structure of Patent Document 2, there is room for improvement in sound insulation in the frequency range.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a sound insulation structure having high sound insulation performance even in a sound range having high sensitivity to human hearing, and a method for manufacturing the same.

The first invention for solving such a problem is a sound insulation structure including a plate material and a plurality of core materials arranged so as to be adjacent to each other on the sound insulation surface of the plate material. The material is a rectangular thin plate material formed in a tubular shape, one end of the core material in the axial direction is joined to the sound insulating surface of the plate material, and the adjacent core materials are joined to each other on the side wall portion thereof. It is characterized by being slidable.

According to the sound insulation structure having such a configuration, the adjacent core materials are not adhered to each other and can slide with each other, so that the vibration of the core materials does not affect the adjacent core materials. Therefore, each core material can efficiently attenuate the vibration. Such a sound insulation structure has excellent attenuation efficiency in a range of human hearing sensitivity, particularly in a range of 2500 to 5000 Hz.

In the sound insulation structure of the present invention, it is preferable that a gap is formed between the ends of the rectangular thin plate material, and the side wall portion of the core material has a slit portion along the axial direction. According to such a sound insulation structure, since the ends of the rectangular thin plate materials are open to each other, the core material easily vibrates and the damping efficiency becomes high.

Further, in the sound insulation structure of the present invention, it is preferable that the core material and the sound insulation surface are joined by an epoxy adhesive. According to such a sound insulation structure, only the bottom surface portion of the core material can be easily fixed to the plate material.

Further, in the sound insulation structure of the present invention, it is preferable that the core material and the sound insulation surface are joined by an adhesive having a shore hardness of 50 or more after curing. According to such a sound insulation structure, the attenuation efficiency in the sound range of 2500 to 5000 Hz can be further increased.

In the sound insulation structure of the present invention, the height of the adhesive after curing from the sound insulation surface is preferably 5% or less of the axial dimension of the core material. According to such a sound insulation structure, only the lower end portion of the core material is fixed, and vibration is likely to occur above the lower end portion of the core material, so that the damping efficiency can be increased.

Further, in the sound insulation structure of the present invention, it is preferable that the core material has the same diameter before and after adhesion to the sound insulation surface. According to such a sound insulating structure, no stress is applied to the core material after bonding, so that the core material is more likely to vibrate and the damping efficiency is further improved.

Further, in the sound insulation structure of the present invention, it is preferable that a plate-shaped damping material is attached to the surface of the plate material. According to such a sound insulation structure, the attenuation efficiency can be further increased in the sound range of 6000 Hz or higher.

The second invention for solving the above-mentioned problems is a core material forming step of forming a core material, an adhesive applying step of applying an adhesive to the surface of a plate material, and a sound insulating surface to which the adhesive is applied. A method for manufacturing a sound insulation structure, which comprises a core material bonding step of arranging a plurality of the core materials and adhering them to the plate material, and a curing step of curing the adhesive.

According to the method of manufacturing such a sound insulation structure, only the lower end portion of the adjacent core materials is adhered to each other, the upper portion is not adhered to each other, and the core materials can slide with each other. Does not affect the adjacent core material. Therefore, each core material can efficiently attenuate the vibration.

In the method for producing a sound insulation structure of the present invention, in the core material forming step, it is preferable to process a rectangular thin plate material into a tubular shape to form a core material. According to the method for manufacturing such a sound insulation structure, a core material can be easily formed.

In the method for producing a sound insulation structure of the present invention, in the core material bonding step, it is preferable that the core material is arranged in parallel on the plate material in the original state. According to such a method for manufacturing a sound insulation structure, stress is not applied to the core material after bonding, so that the core material is more likely to vibrate and the damping efficiency is further improved.

In the method for producing a sound insulation structure of the present invention, in the adhesive coating step, the adhesive has a thickness such that the adhesion height of the adhesive to the core material is 5% or less of the axial dimension of the core material. It is preferable to apply the agent to the surface of the plate material. According to such a method for manufacturing a sound insulation structure, only the lower end portion of the core material can be fixed to the plate material, and a sliding portion on the upper end side of the core material can be sufficiently secured.

According to the present invention, high sound insulation performance can be obtained even in a range of human hearing sensitivity.

It is a perspective view which showed the sound insulation structure which concerns on embodiment of this invention. (A) is a perspective view showing a rectangular thin plate material before processing, and (b) is a perspective view showing a core material formed by processing. It is an enlarged bottom view which showed the sound insulation structure which concerns on embodiment of this invention. (A)-(d) are perspective views for explaining the manufacturing method of the sound insulation structure which concerns on embodiment of this invention. It is a graph which showed the result of the sound insulation experiment performed by changing the fixed condition. It is a graph which showed the result of the sound insulation experiment performed by changing the adhesive. It is a graph which showed the result of the sound insulation experiment performed by changing the manufacturing condition of a core material. It is a graph which showed the result of the sound insulation experiment performed by changing the arrangement condition of a core material. It is a graph which showed the result of the sound insulation experiment performed by changing the composition of a plate material. It is a perspective view which showed the deformation example of a core material.

The sound insulation structure according to the embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the sound insulation structure 1 of the present embodiment includes a plate material 10, a core material 20, and a frame material 30.

The plate member 10 is a base member for fixing the core member 20, and has, for example, a rectangular planar shape. The plate material 10 is, for example, a metal plate made of an aluminum alloy and has a thickness of 1 mm. The material and thickness of the plate material 10 are an example, and are appropriately determined according to the shape and weight of the core material 20 to be attached. A frame member 13 is attached to the peripheral edge of the plate member 10. The frame material 13 is made of, for example, an extruded shape material made of an aluminum alloy, and is formed in a rectangular frame shape along the outer peripheral shape of the plate material 10. The frame member 13 is attached over the entire circumference of the peripheral edge of the plate member 10 so as to surround the core member 20.

As shown in FIG. 2, the core material 20 is formed by bending a rectangular thin plate material 21 (see (a) of FIG. 2) into a cylindrical shape. The rectangular thin plate member 21 is made of an aluminum alloy and is formed in a thin plate shape of, for example, 0.2 mm. The material, thickness, and the like of the rectangular thin plate material 21 are appropriately determined according to the required sound absorption performance, and the shape such as the core diameter and core height of the core material 10 is appropriately determined. The core diameters are, for example, 12 mm, 28 mm, and 50 mm, and the core heights are, for example, 12 mm, 25 mm, 50 mm, and 100 mm. As shown in FIG. 2B, the core material 20 is formed in a circular (shaped) cross section in which the ends 24, 24 of the rectangular thin plate member 21 overlap each other.

As shown in FIG. 1, a plurality of core materials 20 are provided, and are arranged so as to be adjacent to each other on the sound insulating surface 11 of the plate material 10. The side wall portion 22 of the core material 20 is in contact with the side wall portion 22 of another adjacent core material 20. The core material 20 is fixed to the plate material 10 by, for example, an epoxy-based adhesive 12. Specifically, one end of the core material 20 in the axial direction is adhered to the sound insulating surface 11 of the plate material 10. As shown in FIG. 3, the height of the adhesive 12 from the sound insulating surface 11 after curing (the height of the adhesive 12 adhering to the core material 20) is 5% or less of the axial dimension of the core material 20. ing. That is, only one end of the core material 20 in the axial direction is adhered to the sound insulation surface 11, and the portion near the other end (the side away from the plate 10) excluding one end is the adjacent core material 20. It is not adhered, and the side wall portions 22, 22 can slide with each other.

The core material 20 has the same diameter before and after adhesion to the sound insulating surface 11. That is, the core material 20 is in a state of being bonded and not stressed.

The adhesive 12 is an epoxy-based adhesive. As the epoxy-based adhesive, a highly durable adhesive type two-component adhesive is suitable. The main agent of the adhesive 12 is an epoxy resin, and the curing agent is a modified silicone resin. The shore hardness of the adhesive 12 after curing is 50 or more (62 in this embodiment).

Next, a method of manufacturing the sound insulation structure of the present embodiment will be described. The method for manufacturing the sound insulation structure includes a core material forming step, a frame material attaching step, an adhesive coating step, a core material parallel step, and a curing step.

The core material forming step is a preparatory step before manufacturing the sound insulation structure, and is a step of forming the core material 20 in advance. In the core material forming step, as shown in FIG. 2, the rectangular thin plate material 21 is processed into a tubular shape to form the core material 20. The rectangular thin plate member 21 has a short side dimension equivalent to the height dimension (axis direction dimension) of the core material 20 and a long side dimension larger than the circumferential dimension of the core material 20 by the amount of overlap between the ends. There is. Such a rectangular thin plate member 21 is curved so that the ends 24, 24 overlap each other and have the same curvature over the entire circumference. The core material 20 is formed so as to have the same shape and dimensions as after bonding. That is, the core material 20 has the same diameter before and after adhesion to the sound insulating surface 11. The processing method of the core material 20 is not limited to the above-mentioned form, and an extruded shape material having a C-shaped cross section may be formed and cut to a predetermined length.

The frame material attaching step is a step of attaching the frame material 12 on the plate material 10 (see (a) of FIG. 4) as shown in FIG. 4 (b). The frame material 12 is attached to the plate material 10 by using a fastening member such as a bolt. The mounting means of the frame member 12 is not limited to the fastening member, and may be mounted with an adhesive. Further, the frame material attachment step may be performed after the following adhesive application step.

The adhesive application step is a step of applying an adhesive to the surface of the plate material. As shown in FIG. 4C, the adhesive 12 is applied to the inside of the frame material 13 over the entire surface of the plate material 10 on the side that becomes the sound insulation surface 11. The coating thickness of the adhesive 12 is such that the height of adhesion of the adhesive 12 to the core material 20 when the core material 20 is installed does not exceed 5% of the axial dimension of the core material 20. The adhesive 12 is pushed away by the core material 20 when the core material 20 is installed. Therefore, the coating thickness of the adhesive 12 is set to be smaller than the adhesion height to the core material 10 (for example, about 0.5 mm).

The core material bonding step is a step of arranging a plurality of core materials 20 on the sound insulating surface 11 coated with the adhesive 12 and adhering them to the plate material 10. As shown in FIG. 4D, core materials 20 having the same shape are used, and six core materials 20 are arranged in parallel with one core material 20 so as to be in contact with each other at an equal angle pitch. At this time, the side wall portions 22, 22 of the adjacent core materials 20, 20 are in contact with each other over the entire length in the axial length direction. At the lower ends of the core materials 20 and 20, the adhesive 12 adheres to the inner side surface (opposite surface of the abutting side), and the core material 20 is adhered to the plate material 10. The adhesive 12 is pushed by the core materials 20 and 20 and slightly swells, but the adhesive height of the adhesive 12 does not exceed 10% of the axial dimension of the core material 20. The core material 20 is arranged in parallel on the sound insulating surface 11 of the plate material 10 in the original state without being deformed. As a result, the diameter of the core material 20 becomes the same before and after the adhesion to the sound insulating surface 11.

The curing step is a step of curing the adhesive 12 for a predetermined time. The adhesive 12 cured through the curing step has a shore hardness of 62.

Next, a comparative experiment of the sound insulation effect will be described using the sound insulation structure 1 of the present embodiment and the sound insulation structure and the comparative example according to the modified example. In the comparative experiment, sound was incident from the sound insulation surface side at a plurality of incident angles for each example and the comparative example, and the volume insulation was measured for each. The frequency was tested in the range of 400 Hz to 5000 Hz. The core material 20 used in this experiment has a core diameter of 28 mm and a core height of 50 mm. First, an experiment conducted by changing the fixing conditions of the plate material 10 and the core material 20 will be described.

In the comparative example, only a veneer having the same weight as the plate material 10 is used. The veneer is made of a plate material made of an aluminum alloy and has the same rectangular shape as the plate material 10. The first embodiment is the sound insulation structure 1 of the present embodiment, in which the adhesive 12 is applied to the entire surface of the plate material 10 and the core materials 20 are arranged in parallel. In Example 2a, an adhesive is applied to one end surface of the core material 20 and bonded to the plate material 10. In the third embodiment, the adjacent core materials 20, 20 are adhered to each other, and the integrated core materials 20, 20, ... Are joined to the plate material 10. In the fourth embodiment, the lower end portion of the core material 20 is joined to the plate material 10 by brazing.

As shown in FIG. 5, in this experiment, all of Examples 1a to 4a have higher sound transmission loss and higher sound insulation performance than Comparative Examples (see Ls). Example 1a obtains a higher sound transmission loss than the comparative example in the range of 630 Hz or higher. Among them, it was found that a high acoustic transmission loss was obtained in the range of 2000 Hz to 5000 Hz, which is highly sensitive to human hearing (see L1a), and a high sound insulation performance was obtained. Although the sound transmission loss of Example 2a is lower than that of Example 1a, the experimental results close to those of Example 1a have been obtained, and high sound insulation performance can be ensured (see L2a). Examples 3a and 4a have lower sound transmission losses than Examples 1a and 2a, but are higher than those of Comparative Examples, and a certain sound insulation performance is obtained (see L3a and L4a).

From the above, the core material 20 has the sound insulation performance of Examples 1a and 2a in which the adjacent core materials 20 and 20 are not fixed to each other because only the lower end portion thereof is adhered to the plate material 10. It can be seen that it is higher than 3a and 4a. This is because the adjacent core materials 20 and 20 are not fixed to each other and can slide with each other, so that the vibration of each core material 20 does not affect the adjacent core material 20, so that the sound insulation performance is improved. It is thought that it is. In Examples 3a and 4a, since the core materials 20 are fixed to each other, the sound insulation performance is lower than that of Examples 1a and 2a, but the sound insulation performance is higher than that of the comparative example due to the provision of the core material 20. There is.

Next, an experiment conducted by changing the hardness of the adhesive 12 for joining the plate material 10 and the core material 20 will be described. The comparative example is the same as the above experiment. Example 1b is the sound insulation structure 1 of the present embodiment, in which the plate material 10 and the core material 20 are adhered to each other by using an epoxy-based adhesive 12. The shore hardness of the adhesive 12 is 62. In Example 2b, a silicone-based adhesive is used. The shore hardness of this adhesive is 60, which is softer than the adhesive 12 of Example 1b. In Example 3b, a silicone-based adhesive is used. The shore hardness of this adhesive is 37, which is even softer than the adhesive of Example 2b.

As shown in FIG. 6, in this experiment, Examples 1b to 3b have higher sound transmission loss and higher sound insulation performance than Comparative Examples (see Ls). In both Examples 1b to 3b, the results of the experiments are close to those of the above experiment, and high sound transmission loss is obtained in the range of 2000 Hz to 5000 Hz, which is easy for humans to hear. That is, it was found that high sound insulation performance was obtained in all Examples 1b to 3b. Comparing the respective Examples 1b to 3b, it was found that the sound transmission loss increased in the order of Example 1b (see L1b), Example 2b (see L2b), and Example 3b (see L3b). That is, the larger the shore hardness of the adhesive, the higher the sound transmission loss and the higher the sound insulation performance can be ensured. From the above, it is preferable that the shore hardness of the adhesive is 50 or more. More preferably, the shore hardness of the adhesive is 60 or more in Example 2b.

Next, an experiment conducted by changing the installation conditions of the core material 20 will be described. Example 1c is the sound insulation structure 1 of the present embodiment, in which the core material 20 has the same shape before and after bonding. That is, the core material 20 is adhered in a state where no stress is applied. On the other hand, in Example 2c, when the core material 20 is installed, the core material 20 is compressed inward in the radial direction. That is, the core material 20 is adhered in a stressed state.

As shown in FIG. 7, Example 1c obtains a higher sound transmission loss than Comparative Example (see Ls) in the range of 630 Hz or higher. Among them, it was found that a high acoustic transmission loss was obtained in the range of 2000 Hz to 5000 Hz, which is highly sensitive to human hearing, and a high sound insulation performance was obtained (see L1c). It was found that Example 2c obtained the same acoustic transmission loss as that of Example 1c at 1600 Hz or lower, but the acoustic transmission loss was significantly lower than that of Example 1c at 2000 Hz or higher (see L2c). That is, when the core material 20 is not stressed, a high sound transmission loss is obtained and a high sound insulation performance can be obtained.

Next, an experiment conducted by changing the arrangement conditions of the core material 20 will be described. Example 1d is the sound insulation structure 1 of the present embodiment, in which adjacent core materials 20 are in contact with each other without gaps (not bonded). On the other hand, in the second comparative example (see L2s), adjacent core materials are arranged at a distance of about 1 mm, and one end of the core material is adhered to the plate material. The number of core materials of Example 1d and the number of core materials of the second comparative example are the same. Therefore, the area of the sound insulation structure of the second comparative example is larger than that of the first embodiment.

As shown in FIG. 8, Example 1d (see L1d) and Second Comparative Example (see L2s) have obtained the same sound transmission loss. The sound insulation structure of the present invention is equivalent to the second comparative example in which the core materials 20 and 20 adjacent to each other are in contact with each other, but the core materials are not integrated by brazing or adhesion. Sound absorption effect can be obtained. In Example 1d of the present invention, the area of the shielding structure can be made smaller than that in the second comparative example, so that the installation space can be made smaller.

Next, an experiment conducted by changing the composition of the plate material will be described. Example 1e is the sound insulation structure 1 of the present embodiment. In the second embodiment, the damping material is attached to the entire surface of the transparent side of the plate material (the back side of the adhesive surface of the core material). The damping material is formed in a plate shape, and is made of, for example, butyl rubber having a thickness of 2 mm. The comparative example is the same as the second comparative example. In this experiment, the frequency range is expanded to 10000 Hz.

As shown in FIG. 9, the first comparative example (see L5a), the second comparative example (see L5b), and the second comparative example (see Ls2) obtained the same sound transmission loss in the frequency region of 5000 Hz or less. There is. It was found that when the frequency exceeded 6000 Hz, Example 2e obtained higher sound transmission loss than Example 1e and the second comparative example, and obtained high sound insulation performance (see L5b). It is considered that when the damping material is attached to the plate material, in addition to the effect of the mass law, the deterioration of the sound insulation performance due to the coincidence effect is significantly improved in the region where the frequency is high. That is, when sound insulation performance is desired in a high frequency band exceeding 6000 Hz, it is preferable to attach a damping material to the plate material.

As described above, according to the sound insulation structure 1 and the method for manufacturing the sound insulation structure 1 according to the present embodiment, the following effects can be obtained. In the sound insulation structure 1, the adjacent core materials 20 and 20 are not adhered to each other and can slide with each other, so that the vibration of each core material 20 does not affect the adjacent core material 20. Therefore, each of the core materials 20 and 20 can efficiently absorb sound energy. The sound insulation structure 1 of the present embodiment has excellent sound absorption efficiency in a sound range that is sensitive to human hearing, especially in a sound range of 2500 to 5000 Hz.

Since the core material 20 and the sound insulating surface 11 are joined by an epoxy adhesive 12, only the bottom surface of the core material 20 can be easily fixed to the plate material, and the core material 20 can be easily fixed like brazing. , 20 are not fixed to each other. Further, since the shore hardness of the adhesive 12 after curing is 50 or more, the sound absorption efficiency in the sound range of 2500 to 5000 Hz can be further increased.

Since the height of the adhesive 12 from the sound insulating surface 11 (adhesion height to the core material 20) after curing is 10% or less of the axial dimension of the core material 20, only the lower end portion of the core material 20 is a plate material. It is fixed to 10 and easily vibrates above the lower end of the core material 20. Therefore, the sound absorption efficiency can be further increased.

Since the core material 20 has the same diameter before and after bonding to the sound insulating surface 11, no stress is applied to the core material 20 after bonding. As a result, the core material 20 is more likely to vibrate, and the sound absorbing effect is further enhanced.

Although the embodiments of the present invention have been described above, the design can be appropriately changed within a range not contrary to the gist of the present invention. For example, in the above-described embodiment, the adhesive 12 is an epoxy-based adhesive, but the present invention is not limited to this. Other adhesives such as silicone may be used as long as a certain level of shore hardness can be obtained. When the shore hardness is 50 or more, the same action and effect as those of the above-described embodiment can be obtained.

Further, in the above-described embodiment, the core material 20 has a circular (shaped) cross section in which the ends 24, 24 of the rectangular thin plate member 21 overlap each other, but the present invention is not limited to this. For example, as shown in FIG. 10, the rectangular thin plate member 21 is formed so as to have a gap between the longitudinal end portions 24, 24, and the side wall portion 22 of the core material 20 is a slit portion 23 along the axial direction. It may have a cylindrical shape having. Further, the shape is not limited to a cylindrical shape, and may be an elliptical shape or a square shape having a slit portion 23. Further, it may have a tubular shape in which the ends of the rectangular thin plate members are butted against each other without overlapping portions or slit portions. Even with other shapes, the same effects as those of the above-described embodiment can be obtained. If the shape has the slit portion 23, the core material 20 tends to vibrate.

Further, in the above embodiment, the core material 20 is fixed to the plate material 10 by using the adhesive 12, but the core material 20 is not limited thereto. It may be fixed by other joining methods such as brazing and welding. Even with other joining methods such as brazing, it is preferable to use an adhesive, although a certain effect can be obtained.

1 Sound insulation structure 10 Plate material 11 Sound insulation surface 12 Adhesive 20 Core material 21 Rectangular thin plate material 22 Side wall part 23 Slit part 24 End part 30 Frame material

Claims (11)

A sound insulation structure including a plate material and a plurality of core materials arranged so as to be adjacent to each other on the sound insulation surface of the plate material.
The core material is a rectangular thin plate material formed in a tubular shape.
One end of the core material in the axial direction is joined to the sound insulating surface of the plate material.
A sound insulation structure characterized in that adjacent core materials are slidable with each other on their side wall portions. A gap is formed between the ends of the rectangular thin plate material.
The sound insulation structure according to claim 1, wherein the side wall portion of the core material has a slit portion along the axial direction. The sound insulation structure according to claim 1 or 2, wherein the core material and the sound insulation surface are joined with an epoxy-based adhesive. The sound insulation structure according to claim 1 or 2, wherein the core material and the sound insulation surface are joined by an adhesive having a shore hardness of 50 or more after curing. The sound insulation structure according to claim 3 or 4, wherein the height of the adhesive after curing from the sound insulation surface is 5% or less of the axial dimension of the core material. The sound insulation structure according to any one of claims 3 to 5, wherein the core material has the same diameter before and after adhesion to the sound insulation surface. The sound insulation structure according to any one of claims 1 to 6, wherein a plate-shaped vibration damping material is attached to the surface of the plate material. The core material forming process for forming the core material and
Adhesive application process to apply adhesive to the surface of the plate material,
A core material bonding step of arranging a plurality of the core materials on a sound insulating surface coated with the adhesive and adhering them to the plate material.
A method for manufacturing a sound insulation structure, which comprises a curing step of curing the adhesive. The method for manufacturing a sound insulation structure according to claim 8, wherein in the core material forming step, a rectangular thin plate material is processed into a tubular shape to form a core material. The method for manufacturing a sound insulation structure according to claim 8 or 9, wherein in the core material bonding step, the core material is arranged in parallel on the plate material in the original state. The adhesive coating step is characterized in that the adhesive is applied to the surface of the plate material at a thickness such that the adhesion height of the adhesive to the core material is 5% or less of the axial dimension of the core material. The method for manufacturing a sound insulation structure according to any one of claims 8 to 10.

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