Cushioning sound insulation pad

Abstract

The present application relates to a buffering sound insulation mat. The buffering sound insulation mat of an embodiment includes a 3D vertical nonwoven fabric layer having a structure in which wavy short fibers are arranged vertically, a sound absorbing layer on one or both sides of the 3D vertical nonwoven fabric layer, and an olefin-based powder layer between the 3D vertical nonwoven fabric layer and the sound absorbing layer.

Description

Technical Field

[0001] The present disclosure relates to a buffer sound insulation pad. Background Art

[0002] Usually, such as Figure 1 As shown, a cushioning sound insulation pad is manufactured by forming a heavy layer using a rubber material having a heavy specific gravity such as thermoplastic elastomer (TPE) or ethylene vinyl acetate (EVA) as a sound insulation material 10 and by attaching a sound absorbing material 20 such as polyethylene terephthalate (PET) needle felt or fiberboard felt to the heavy layer.

[0003] Conventionally, the weight of the sound insulation material is increased to improve the sound insulation performance of the cushioning sound insulation mat. However, when the sound insulation material is made of a heavier material, the sound insulation performance is excellent, but there is a problem of causing the fuel efficiency of the vehicle to deteriorate and the cost to increase.

[0004] Therefore, a 3D vertical nonwoven fabric, made by arranging mesh in a vertical direction, was proposed as a material to replace heavy sound insulation materials. However, the thickness of the 3D vertical nonwoven fabric layer recovers again after compression molding, causing interference with adjacent components. The thickness change also reduces the matching degree with the vehicle body, resulting in BSR (buzz, squeak, and rattle) noise. Summary of the Invention

[0005] The present disclosure relates to a sound-absorbing cushion. Certain embodiments relate to a sound-absorbing cushion that can reduce noise and has high numerical stability.

[0006] Thus, embodiments of the present disclosure provide a low-weight cushioning sound insulation mat having high numerical stability and excellent NVH (noise, vibration, and harshness) performance by eliminating the heavy rubber material sound insulation material.

[0007] According to one embodiment of the present invention, a buffer sound insulation pad includes a 3D vertical non-woven fabric layer having a structure of vertically arranged wavy short fibers; a sound absorbing layer arranged on one side or both sides of the 3D vertical non-woven fabric layer; and an olefin-based powder layer arranged between the 3D vertical non-woven fabric layer and the sound absorbing layer.

[0008] The area density of the 3D vertical nonwoven fabric layer may be 500 g / m2 or greater.

[0009] The 3D vertical nonwoven fabric layer may include 50% to 70% by weight of corrugated 8-denier fibers and 30% to 50% by weight of 4-denier low-melting-point fibers.

[0010] The weight ratio of the 3D vertical non-woven fabric layer to the buffer sound insulation pad may be 0.29 to 0.71.

[0011] The sound absorbing layer may be provided with a polyethylene terephthalate (PET) felt layer.

[0012] The sound absorbing layer may be provided with a fiberboard or a needle-punched nonwoven fabric.

[0013] The area density of the sound absorbing layer may be 500 g / m2 or greater.

[0014] The area density of the sound absorbing layer may be 100 g / m2 or less.

[0015] The sound absorbing layer may include 50% or more of 8 denier and 4 denier fibers.

[0016] The sound absorbing layer may include 20% or more of the low-melting-point fiber.

[0017] The sound absorbing layer may be provided with at least one selected from the group consisting of polyethylene (PE), polypropylene (PP), polycarbonate (PC), and a combination of these materials.

[0018] The olefin-based powder layer may be provided with a polyethylene (PE) powder layer.

[0019] The sound absorbing layer may include an upper sound absorbing layer disposed on an upper side of the 3D vertical non-woven fabric layer and a lower sound absorbing layer disposed on a lower side of the 3D vertical non-woven fabric layer.

[0020] The buffering sound insulation pad may further include an upper olefin-based powder layer disposed between the 3D vertical non-woven fabric layer and the upper sound absorbing layer.

[0021] The buffer sound insulation pad may further include a lower olefin-based powder layer disposed between the 3D vertical non-woven fabric layer and the lower sound absorbing layer.

[0022] The weight ratio of the upper olefin-based powder layer may be 0.8 to 0.9 based on the total weight of the upper olefin-based powder layer and the lower olefin-based powder layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] These and / or other features of the present disclosure will become apparent and more readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, in which:

[0024] Figure 1 shows a cross-sectional view of a cushioning sound insulation mat provided with a heavy layer of sound insulation material according to the prior art;

[0025] Figure 2 shows a cross-sectional view of a buffer sound insulation pad according to an embodiment of the present disclosure;

[0026] Figure 3 is a cross-sectional view of a buffer sound insulation pad according to an embodiment of the present disclosure, wherein a PET felt layer is disposed on both sides of a 3D vertical non-woven fabric layer;

[0027] Figure 4 is a cross-sectional view of a buffer sound insulation pad according to an embodiment of the present disclosure, wherein a membrane layer is disposed on both sides of a 3D vertical non-woven fabric layer;

[0028] Figure 5 The figure shows the measurement of the sound absorption rate of the 3D vertical nonwoven fabrics of Inventive Example 1 and Comparative Example 1;

[0029] 6A to 6D The sound absorption rates of Inventive Examples 2 to 5 and Comparative Examples 2 to 5 are measured respectively;

[0030] Figure 7A and Figure 7B The figures show the sound absorption rates of Inventive Example 6 and Comparative Example 6 on the passenger side and the dashboard (dash panel) side, respectively.

[0031] Figure 8 shows the measurement of sound absorption rate according to the amount of upper PE powder when the weight of the lower PE powder is 20 g / m2;

[0032] Figure 9 shows measurements of sound absorption rates of Inventive Examples 7 to 11 and Comparative Examples; and

[0033] Figure 10A and Figure 10B Comparison of the sound insulation performance and sound absorption performance between Inventive Example 12 and the comparative example is shown. DETAILED DESCRIPTION

[0034] This specification does not describe all elements of the embodiments, and general contents in the technical field to which the present disclosure pertains or overlapping contents between the embodiments will be omitted.

[0035] In addition, unless there is a special description to the contrary, when a section “includes” a certain component, it means that other components may be further included, rather than excluding other components.

[0036] Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0037] Hereinafter, embodiments of the present disclosure will be described in detail.

[0038] In the buffer sound insulation pad according to the embodiment of the present disclosure, Figure 2 As shown, the sound absorbing layers 210 and 220 are provided on one or both sides of the 3D vertical non-woven fabric layer 100 , and the 3D vertical non-woven fabric layer 100 and the sound absorbing layers 210 and 220 are bonded to each other through the olefin-based powder layers 310 and 320 .

[0039] The 3D vertical non-woven fabric layer 100 includes wavy short fibers arranged in a vertical direction.

[0040] Compared with ordinary short fibers, the wavy short fibers have lower rebound elasticity and are more flexible, so it can prevent the buffer sound insulation pad from returning to its original thickness after the non-woven fabric is preheated and pressed.

[0041] The 3D vertical nonwoven fabric layer 100 may include 8-denier wavy staple fibers in a range of 50% to 70%. If the content is less than 50%, the elasticity of the vertical structure is reduced and molding failure may occur, which is not preferred. If the content is greater than 70%, the content of the binder fibers is reduced and the fibers cannot be compressed well to the molding thickness, which is not preferred.

[0042] In addition, the 3D vertical non-woven fabric layer 100 may include 30% to 50% of low-melting point fibers (LM).

[0043] For example, it can be prepared by using 55% of 8-denier wavy staple fibers and 45% of 4-denier low-melting-point staple fibers.

[0044] The 3D vertical non-woven fabric layer 100 may have a thickness of 10 mm or less before being formed.

[0045] The 3D vertical nonwoven fabric layer 100 may have a density of 500 g / m2 (g / m 2 ) or more, and preferably 600 to 1500 g / m2. If the surface density is less than 600 g / m2, it is not preferred because there is a limit to vertically arranging the wavy staple fibers and the thickness of the nonwoven fabric may become thin. If it exceeds 1500 g / m2, it is not preferred because, when used, molding defects may occur due to the excessive number of fibers per unit volume.

[0046] The 3D vertical non-woven fabric layer 100 may have a weight ratio of 0.29 to 0.71 based on the total weight of the 3D vertical non-woven fabric layer 100. Within this weight ratio range, optimal sound absorption performance is exhibited in a frequency range of 2000 Hz or more.

[0047] The sound absorbing layers 210 and 220 enhance the formability of the buffer sound insulation pad itself and have high viscous resistance against noise due to high air flow resistance, thereby improving the sound absorption performance.

[0048] The sound absorbing layers 210 and 220 may be made of polyethylene terephthalate (PET) felt. Felt is made by horizontally stacking a non-woven fabric called a mesh of approximately 10 g / m2. By controlling airflow resistance, polyethylene terephthalate (PET) felt can maximize sound absorption and sound insulation performance.

[0049] The sound absorbing layers 210 and 220 may include ordinary staple fibers, low-melting staple fibers, and recycled PET. The sound absorbing layers 210 and 220 may include 50% or more of 8 denier and 4 denier fibers and 20% or more of low-melting staple fibers (LM).

[0050] Preferably, the sound absorbing layers 210 and 220 may be prepared by using 50% of 8-denier ordinary staple fibers, 30% of 8-denier recycled PET, and 20% of 4-denier low-melting-point staple fibers.

[0051] In addition, the sound absorbing layers 210 and 220 may be manufactured to have a thickness of 10 mm or less before molding.

[0052] Furthermore, the surface density of the sound absorbing layers 210 and 220 may be 500 g / m² or greater, and preferably 800 g / m² to 1500 g / m². If the surface density is less than 800 g / m², it is not preferred because it may be difficult to maintain the shape of the part after hot press molding. If it exceeds 1500 g / m², it is not preferred because heat transfer to the interior of the felt is reduced during hot press molding, and molding defects may occur due to the excessive number of fibers per unit volume.

[0053] In addition, the sound absorbing layers 210 and 220 are scrim layers and may be PET felt having an area density of 100 g / m 2 or less in consideration of weight and manufacturing cost.

[0054] In addition, the sound absorbing layers 210 and 220 may be needle-punched nonwoven fabrics or fiberboard. Needle-punched nonwoven fabrics are nonwoven fabrics in which felt is interwoven with needles to impart rigidity, and fiberboard nonwoven fabrics are nonwoven fabrics having a relatively small amount of needle punching and a greater thickness than needle-punched nonwoven fabrics.

[0055] The sound absorbing layer according to an embodiment of the present disclosure is limited to the above-mentioned fiber composition, but is not limited thereto and may be manufactured using a conventional fiber composition.

[0056] The olefin-based powder layers 310 and 320 not only bond the sound absorbing layers 210 and 220 and the 3D vertical nonwoven fabric 100 to each other, but also have fine ventilation holes formed between the powder particles, thereby enhancing the sound absorption performance. The sound absorption performance can be controlled by controlling the ventilation holes.

[0057] The olefin-based powder layers 310 and 320 may be polyethylene (PE) powder layers, and the PE powder may have a weight per unit area in the range of 100 to 300 g / m2. If the PE powder weight per unit area is less than 100 g / m2, the bonding strength is weak, and as the amount of PE powder increases, the bonding strength improves. However, if the weight per unit area exceeds 300 g / m2, the airflow resistance becomes excessively high, thereby reducing the sound absorption performance. This is undesirable.

[0058] When the sound-absorbing layer is provided on both sides of the 3D vertical non-woven fabric layer 100, the sound-absorbing layer includes an upper sound-absorbing layer 210 provided on the upper side of the 3D vertical non-woven fabric layer 100 and a lower sound-absorbing layer 220 provided on the lower side of the 3D vertical non-woven fabric layer 100. For example, the upper sound-absorbing layer 210 may be provided with a PET felt layer having an areal density of 500 g / m² or greater, and the lower sound-absorbing layer 220 may be provided with a PET felt layer having an areal density of 100 g / m² or less. The upper and lower sound-absorbing layers 210, 220 may be attached to the 3D vertical non-woven fabric layer 100 using olefin-based powder. In this case, the upper and lower sound-absorbing layers may include an upper olefin-based powder layer 310 interposed between the 3D vertical non-woven fabric layer 100 and the upper sound-absorbing layer 210, and a lower olefin-based powder layer 320 interposed between the 3D vertical non-woven fabric layer 100 and the lower sound-absorbing layer 220. The weight ratio of the upper olefin-based powder layer 310 to the lower olefin-based powder layer 320 may be in the range of 8:2 to 9:1. That is, based on the total weight of the upper olefin-based powder layer 310 and the lower olefin-based powder layer 320, the weight ratio of the upper olefin-based powder layer 310 may be 0.8 to 0.9.

[0059] The buffer sound insulation pad according to an embodiment of the present invention may be formed by providing a PET felt layer 230 having an area density of 100 g / m2 or less on one side or both sides of the 3D vertical non-woven fabric layer 100, such as Figure 3 As shown in FIG. The 3D vertical nonwoven fabric layer 100 according to an embodiment of the present disclosure has better sound absorption performance than conventional 3D vertical nonwoven fabrics made of ordinary staple fibers. Therefore, by omitting the PET felt layer, which is the conventional hard layer, and enhancing only the sound absorption performance of the 3D vertical nonwoven fabric, it is possible to control NVH performance.

[0060] In addition, if Figure 4 As shown, a film layer 240 can be formed on one or both sides of the 3D vertical non-woven fabric layer 100. The film layer 240 is an airtight material. In this case, the film layer 240 can form a sound insulation structure and can be formed by vacuum and pressing. The film layer 240 can be formed from one or more of polyethylene (PE), polypropylene (PP), polycarbonate (PC), and combinations of these materials, but is not limited thereto.

[0061] Hereinafter, specific inventive examples and comparative examples of the embodiments of the present disclosure are given, and the effects of the inventive examples are described through sound absorption performance evaluation.

[0062] Evaluation test

[0063] In the rebound evaluation of the inventive examples and comparative examples according to the embodiments of the present disclosure, the thickness change was measured after the raw material was pressed and heated. The sound absorption performance was measured and compared according to the sound absorption rate measurement method ISO 354 / JIS A1409 and ISO 10534-2 / ASTM E2611-09.

[0064] 1. Evaluation of the rebound of 3D vertical nonwoven fabrics based on the application of wavy staple fibers.

[0065] Rebound evaluation was performed on a 3D vertical nonwoven fabric to which wavy short fibers were applied as an inventive example according to an embodiment of the present disclosure and a 3D vertical nonwoven fabric to which conventional ordinary short fibers were applied as a comparative example.

[0066] Inventive Example 1 and Comparative Example 1 have the structures shown in Table 1 below, are press-molded to have final thicknesses of 1 mm, 6 mm, and 15 mm, as shown in Table 2, and the thickness changes are measured after heat resistance at 80°C and 90°C, and the measured thickness changes are shown in Table 1 below.

[0067] Table 1

[0068] structure Raw material thickness Invention Example 1 3D vertical nonwoven fabric using wavy short fibers 25 mm Comparative Example 1 3D vertical nonwoven fabric using ordinary short fibers 25 mm

[0069] Table 2

[0070]

[0071] As shown in Table 2 above, the thickness of the 3D vertical nonwoven fabric layer using wavy staple fibers in Inventive Example 1 according to an embodiment of the present disclosure after heat resistance at 80°C varied from 0.1 to 1.5 mm, while the thickness of Comparative Example 1 varied from 0.2 to 2.8 mm. Inventive Example 1 showed a 50% improvement in springback compared to Comparative Example 1.

[0072] 2. Evaluation of the sound absorption performance of 3D vertical nonwoven fabrics based on the application of wave-type staple fibers.

[0073] As shown in Table 3 below, Inventive Example 1 (3D vertical nonwoven fabric using the wavy short fibers according to the present disclosure) and Comparative Example 1 (low-density vertical nonwoven fabric using conventional ordinary short fibers) were prepared to evaluate sound absorption.

[0074] Table 3

[0075] structure Invention Example 1 3D vertical nonwoven fabric using wavy short fibers Comparative Example 1 3D vertical nonwoven fabric using ordinary short fibers

[0076] like Figure 5As shown, the sound absorption performance of Inventive Example 1 according to the embodiment of the present disclosure is improved by 5-10% compared with Comparative Example 1.

[0077] 3. Evaluation of the sound absorption performance of 3D vertical nonwoven fabrics and fiberboard (or N / P nonwoven fabrics).

[0078] As shown in Table 4 below, Inventive Examples 2 to 5 (3D vertical nonwoven fabrics according to embodiments of the present disclosure) and Comparative Examples 2 to 5 (fiberboard or needle-punched nonwoven fabrics (N / P nonwoven fabrics) with a weight 10% higher than that of the Inventive Examples) were prepared. The sound absorption performance was then evaluated using an impedance tube. The material thickness was uniform for each Inventive Example and Comparative Example.

[0079] Table 4

[0080]

[0081]

[0082] like 6A to 6D As shown, even though the weight is 10% lower than that of Comparative Examples 2 to 5 (ordinary fiberboard or non-woven fabric), Inventive Examples 2 to 5 according to the embodiments of the present disclosure have excellent sound absorption performance.

[0083] 4. Evaluation of the sound absorption performance of the soft layer based on the application of 3D vertical nonwoven fabric.

[0084] As shown in Table 5 below, Inventive Example 6, which bonded a 3D vertical nonwoven fabric according to an embodiment of the present disclosure to a needle-punched nonwoven fabric (N / P nonwoven fabric) using PE powder, and Comparative Example 6, which bonded a conventional fiberboard to a needle-punched nonwoven fabric (N / P nonwoven fabric), were prepared. Sound absorption was evaluated on the passenger side and the instrument panel side. The thickness of the raw materials was uniformly 24 mm.

[0085] Table 5

[0086]

[0087] like Figure 7A and Figure 7B As shown, Inventive Example 6 according to an embodiment of the present disclosure has 5-15% better sound absorption performance than Comparative Example 6, and the passenger side shows a higher improvement in sound absorption performance than the instrument panel side.

[0088] 5. Evaluation of sound absorption performance according to the weight ratio of PE powder.

[0089] A cushioning sound insulation mat was prepared according to an embodiment of the present disclosure by sequentially stacking a 1000 g / m2 PET felt layer, an upper PE powder layer, a 3D vertical nonwoven fabric, a lower PE powder layer, and a 30 g / m2 PET felt layer. The weights of the upper and lower PE powder layers were as shown in Table 6 below, and the average sound absorption coefficient was measured.

[0090] Table 6

[0091]

[0092] As shown in Table 6 and Figure 8 As shown, with a lower powder weight of 20 g / m², the best sound absorption performance was achieved when the upper powder layer weighed 100 to 250 g / m², i.e., when the weight ratio of the upper PE powder to the lower PE powder was 8:2 to 9:1. A higher amount of lower PE powder increased airflow resistance, resulting in excellent adhesion and higher sound absorption performance. However, at 300 g / m² or higher, airflow resistance became excessive and sound absorption performance deteriorated.

[0093] 6. Evaluation of sound absorption performance according to the weight ratio of the sound absorbing layer to the 3D vertical nonwoven fabric.

[0094] A cushioning sound insulation mat according to the present disclosure was prepared by sequentially stacking a high-density PET felt layer (hard layer), an upper PE powder layer, a 3D vertical non-woven fabric (soft layer), a lower PE powder layer, and a PET felt layer. A comparative example was also prepared by sequentially stacking a conventional hard layer, a TPE sound insulation layer, and a soft layer. The weights of the prepared hard and soft layers are shown in Table 7 below, and the average sound absorption coefficient was measured. In this case, the PE powder content in the inventive example was 100 g / m², and the thin layer was 30 g / m².

[0095] Table 7

[0096]

[0097] like Figure 9 As shown, when the sound absorption performance of Inventive Examples 7 to 11 is compared with that of the Comparative Examples, the Inventive Examples clearly have higher sound absorption performance than the Comparative Examples. Furthermore, it was found that Inventive Examples 7 to 10 exhibited relatively excellent sound absorption performance, with the weight ratio (hard layer:soft layer) being 71% or less: 29% or greater in the 2000 Hz and above region.

[0098] 7. Real vehicle NVH evaluation.

[0099] As shown in Table 8 below, Inventive Example 12, which was formed by sequentially stacking a high-density PET felt layer, an upper PE powder layer, a 3D vertical non-woven fabric, a lower PE powder layer, and a thin layer according to an embodiment of the present disclosure, and a Comparative Example, which was formed by sequentially stacking a conventional hard layer, a TPE sound insulation layer, and a soft layer, were prepared and manufactured, and the NVH of a real vehicle was evaluated.

[0100] *Intelligibility Index (AI): A measure of conversation clarity, with higher being better (100 = 100% understanding of the other party's conversation, 0 = 0% understanding of the other party's conversation).

[0101] *Loudness: In addition to the physical value, the noise level perceived by people (Pa dB)

[0102] Table 8

[0103]

[0104] Table 9

[0105] Driver RH Comparative Example Invention Example 12 AI 73.4 75.3 Loudness 22.3 20.9

[0106] As shown in Table 9 above, it can be seen that when evaluating the NVH of a real vehicle, Inventive Example 12 has superior AI (clarity index) and loudness compared to the comparative example. Figure 10A and Figure 10B As shown, compared to the comparative example, the sound insulation performance of Inventive Example 12 decreases slightly with weight, but the sound absorption performance significantly improves. Overall, real vehicle NVH evaluations show that the Inventive Example outperforms the comparative example. In Inventive Example 12, even with the TPE sound insulation layer (heavy layer) removed, the real vehicle NVH performance is superior to that of conventional crash sound insulation mats, thus achieving a weight reduction of 30% or more compared to conventional crash sound insulation mats.

[0107] As described above, the disclosed embodiments have been described with reference to the accompanying drawings. A person skilled in the art of the present disclosure will understand that the present disclosure can be implemented in forms different from the disclosed embodiments without changing the technical ideas or basic features of the present disclosure. The disclosed embodiments are exemplary and should not be interpreted as limiting.

[0108] The cushioning sound insulation mat according to the embodiment of the present disclosure can achieve lighter weight than the existing cushioning sound insulation mat and reduce cost by removing heavy sound insulation materials (heavy layers).

[0109] Compared to existing cushioning mats, cushioning mats according to embodiments of the present disclosure may improve real vehicle NVH performance by significantly increasing sound absorption performance, even if heavy sound insulation materials (heavy layers) are removed.

[0110] Compared with a buffer sound insulation pad using an existing 3D vertical non-woven fabric, the buffer sound insulation pad according to an embodiment of the present disclosure can ensure numerical stability due to a small thickness change after compression molding.

Claims

1. A sound-absorbing cushion, comprising: a 3D vertical nonwoven fabric layer having a structure in which wavy short fibers are arranged vertically; a sound absorbing layer on one side or both sides of the 3D vertical non-woven fabric layer; and an olefin-based powder layer, the olefin-based powder layer being between the 3D vertical non-woven fabric layer and the sound-absorbing layer, wherein the 3D vertical nonwoven fabric layer comprises 50% to 70% by weight of corrugated 8-denier fibers, and The surface density of the 3D vertical non-woven fabric layer is 600 g / m2 to 1500 g / m2.

2. The sound-absorbing cushion according to claim 1, wherein: The 3D vertical nonwoven fabric layer includes 30% to 50% by weight of 4-denier low-melting-point fibers.

3. The sound-absorbing cushion according to claim 1, wherein: The weight ratio of the 3D vertical non-woven fabric layer to the buffer sound insulation pad is 0.29 to 0.

71.

4. The sound-absorbing cushion according to claim 1, wherein: The sound absorbing layer includes a polyethylene terephthalate felt layer.

5. The sound-absorbing cushion according to claim 1, wherein: The sound absorbing layer comprises fiberboard or needle-punched nonwoven fabric.

6. The sound-absorbing cushion according to claim 1, wherein: The surface density of the sound absorbing layer is 500 g / m2 or greater.

7. The sound-absorbing cushion according to claim 1, wherein: The surface density of the sound absorbing layer is 100 g / m2 or less.

8. The sound-absorbing cushion according to claim 1, wherein: The sound absorbing layer includes 50% or more of 8 denier and 4 denier fibers.

9. The sound-absorbing cushion according to claim 1, wherein: The sound absorbing layer includes 20% or more of low-melting-point fibers.

10. The sound-absorbing cushion according to claim 1, wherein: The sound absorbing layer includes at least one of polyethylene, polypropylene, polycarbonate or a combination of these materials.

11. The sound-absorbing cushion according to claim 1, wherein: The olefin-based powder layer includes a polyethylene powder layer.

12. A sound-insulating cushion comprising: a 3D vertical nonwoven fabric layer having a structure in which wavy short fibers are arranged vertically; an upper sound absorbing layer, the upper sound absorbing layer being located on the upper side of the 3D vertical non-woven fabric layer; a lower sound absorbing layer, the lower sound absorbing layer being located on the lower side of the 3D vertical non-woven fabric layer; an upper olefin-based powder layer, the upper olefin-based powder layer being between the 3D vertical non-woven fabric layer and the upper sound-absorbing layer; and A lower olefin-based powder layer, the lower olefin-based powder layer being between the 3D vertical non-woven fabric layer and the lower sound-absorbing layer, wherein the 3D vertical nonwoven fabric layer comprises 50% to 70% by weight of corrugated 8-denier fibers, and The surface density of the 3D vertical non-woven fabric layer is 600 g / m2 to 1500 g / m2.

13. The sound-absorbing cushion according to claim 12, wherein: The upper sound absorbing layer includes a polyethylene terephthalate felt layer having an area density of 500 g / m 2 or more.

14. The sound-absorbing cushion according to claim 12, wherein: The lower sound absorbing layer includes a polyethylene terephthalate felt layer having an area density of 100 g / m 2 or less.

15. The sound-absorbing cushion according to claim 12, wherein: The weight ratio of the upper olefin-based powder layer is 0.8 to 0.9 based on the total weight of the upper olefin-based powder layer and the lower olefin-based powder layer.

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