Heat insulation sound absorption material

Abstract

To provide heat insulation sound absorption materials that have high sound absorption and high heat insulation effects.SOLUTION: A resin fiber aggregate in which fibers are irregularly and intricately intertwined with each other to form spaces between the fibers, and the fiber aggregate has a first peak and a second peak in fiber diameter distribution, and the fiber aggregate is composed of a first aggregate having a first peak and a second aggregate having a second peak, and the average fiber diameter of the first aggregate is 1000 nm or more and 2000 nm or less, and the average fiber diameter of the second aggregate is 4000 nm or more and 8000 nm or less.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a heat-insulating, sound-absorbing material. [Background technology]

[0002] In buildings, vehicles, electronic devices, etc., sound insulation and sound absorption materials are often used to insulate and absorb sounds generated from sound sources. At the same time, heat insulation materials are often used to prevent heat from escaping and to protect against heat. It is known that resin foam materials are used as heat insulation and sound absorption materials (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-130001 A Summary of the Invention [Problem to be solved by the invention]

[0004] When resin foam is used as a heat-insulating sound-absorbing material, it has a sound-proofing effect of bouncing sound back toward the sound source, but does not have a sufficient sound-absorbing effect. In other words, because resin foam bounces sound back, sound reverberates, especially in closed spaces such as indoors, and sufficient results are not obtained in terms of quieting the room.

[0005] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a heat-insulating sound-absorbing material that has both high sound-absorbing effect and high heat-insulating effect.

[0006] The main invention for achieving the above-mentioned object is a thermal insulating sound absorbing material, which is a resin fiber aggregate in which fibers are irregularly and intricately entangled with each other and have spaces between the fibers, and the fiber diameter distribution of the fiber aggregate has a first peak and a second peak, and the fiber aggregate is composed of a first aggregate having the first peak and a second aggregate having the second peak, and the average fiber diameter of the first aggregate is 1000 nm or more and 2000 nm or less, and the average fiber diameter of the second aggregate is 4000 nm or more and 8000 nm or less.

[0007] Other features of the present invention will become apparent from the following detailed description of the present invention and the accompanying drawings. Effect of the Invention

[0008] According to the present invention, it is possible to provide a thermal insulating sound-absorbing material comprising a resin fiber aggregate in which fibers are irregularly and intricately entangled with each other and have spaces between the fibers, the fiber aggregate having a fiber diameter distribution having a first peak and a second peak, the fiber aggregate being composed of a first aggregate having the first peak and a second aggregate having the second peak, the first aggregate having an average fiber diameter of 1000 nm or more and 2000 nm or less, and the second aggregate having an average fiber diameter of 4000 nm or more and 8000 nm or less. [Brief description of the drawings]

[0009] [Figure 1] 1 is an electron microscope photograph of a fiber assembly. [Diagram 2] FIG. 2 is a diagram showing the fiber diameter distribution of a fiber assembly. [Diagram 3] FIG. 4 is a diagram showing the fiber diameter distribution of a first assembly. [Figure 4] FIG. 4 is a graph showing the fiber diameter distribution of a second assembly. [Diagram 5] 1 is a sample list according to the present embodiment. [Figure 6] FIG. 1 is a diagram showing the sound absorption coefficient measurement results of Sample 1. [Figure 7] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 2. [Figure 8] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 3. [Figure 9] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 4. [Figure 10] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 5. [Figure 11] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 6. [Figure 12] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 7. [Figure 13] FIG. 13 is a diagram showing the sound absorption coefficient measurement results of Sample 8. [Figure 14] FIG. 13 is a diagram showing a list of thermal conductivity measurement results. [Figure 15] FIG. 1 shows the results of a mold resistance test.

[0010] At least the following points will become apparent from the description of this specification and the accompanying drawings.

[0011] A thermal insulating sound absorbing material comprising a resin fiber aggregate in which fibers are irregularly and intricately entangled with each other and have spaces between the fibers, the fiber aggregate having a fiber diameter distribution having a first peak and a second peak, the fiber aggregate being composed of a first aggregate having the first peak and a second aggregate having the second peak, the first aggregate having an average fiber diameter of 1000 nm or more and 2000 nm or less, and the second aggregate having an average fiber diameter of 4000 nm or more and 8000 nm or less.

[0012] According to such a heat insulating sound absorbing material, it is possible to provide a heat insulating sound absorbing material having high sound absorbing effect and high heat insulating effect.

[0013] In such a heat-insulating sound-absorbing material, it is preferable that the thickness of the first aggregate in the fiber aggregate is smaller than the thickness of the second aggregate.

[0014] Such a heat-insulating sound-absorbing material can provide a high sound-absorbing effect over the entire frequency range of the sound source.

[0015] In such a heat-insulating sound-absorbing material, it is desirable that the ratio of the thickness of the first assembly to the thickness of the second assembly is 1:4 or less.

[0016] Such a heat-insulating sound-absorbing material can provide a high sound-absorbing effect over the entire frequency range of the sound source.

[0017] In such a heat-insulating sound-absorbing material, it is desirable that the ratio of the thickness of the first assembly to the thickness of the second assembly is 1:9 or less.

[0018] Such a heat-insulating sound-absorbing material can provide a higher sound-absorbing effect at all frequencies of the sound source.

[0019] In the heat insulating and sound absorbing material, the bulk density of the fiber aggregate is 0.05 g / cm 3 It is desirable that the following:

[0020] Such a heat-insulating, sound-absorbing material has a bulk density of 0.05 g / cm 3 By satisfying the following, it is possible to provide a heat insulating sound absorbing material having high sound absorbing effect and high heat insulating effect.

[0021] In such a heat-insulating sound-absorbing material, it is desirable that the sound absorption coefficient of the fiber aggregate is 0.6 or more at frequencies of 400 Hz or more, and 0.85 or more at frequencies of 1000 to 5000 Hz, and that the thermal conductivity of the fiber aggregate is 0.035 W / m·k or less.

[0022] With such a heat-insulating sound-absorbing material, it is possible to provide a heat-insulating sound-absorbing material that combines high sound-absorbing and high heat-insulating effects, with specific values ​​for sound absorption coefficient and thermal conductivity shown.

[0023] In such a heat insulating sound absorbing material, it is desirable that the fiber assembly is judged to have zero mold growth.

[0024] With such a heat-insulating sound-absorbing material, even if mold occurs, the mold cannot grow and the material is not damaged by the mold.

[0025] In the heat and sound absorbing material, it is preferable that the fiber assembly is used as a heat and sound absorbing material for a tent.

[0026] Such a heat-insulating sound-absorbing material can adapt to changes in the external shape of a tent, and has both high sound-absorbing and high heat-insulating properties. ===This embodiment===

[0027] In this embodiment, polypropylene (PP) from among polyolefin resins is used as the material, and this is refined into a fiber aggregate by a melt-blowing method (a detailed description of which is omitted as this is an existing technology) to produce a heat insulating absorbent material.

[0028] This enabled the production of a fiber assembly in which the fibers are irregularly and intricately entangled, with spaces between them, as shown in the electron microscope photograph of the fiber assembly in Figure 1. Furthermore, the melt-blowing method enabled the production of polypropylene with a high degree of purity (refined using only polypropylene without the addition of any additives during the manufacturing process), resulting in the production of a high-purity fiber assembly. <Fiber distribution in fiber assemblies>

[0029] 2 is a graph showing the fiber diameter distribution of the fiber assembly. It can be seen from this graph that the fiber diameter distribution has a first peak from 1000 nm to 2000 nm and a second peak from 4000 nm to 6000 nm. This is because the fiber assembly according to this embodiment is composed of a first assembly having the first peak and a second assembly having the second peak.

[0030] Fig. 3 shows the fiber diameter distribution of the first assembly according to this embodiment, and Fig. 4 shows the fiber diameter distribution of the second assembly according to this embodiment. In this embodiment, the first peak of the first assembly shown in Fig. 3 is in the range of 1000 nm to 2000 nm as described above, and the average fiber diameter of the first assembly is 1445 nm. The second peak of the second assembly shown in Fig. 4 is in the range of 4000 nm to 6000 nm as described above, and the average fiber diameter of the second assembly is 6673 nm.

[0031] In other words, the insulating acoustic absorbent of this embodiment is a resin fiber aggregate in which the fibers are irregularly and intricately entangled with each other, with spaces between the fibers, and the fiber diameter distribution of the fiber aggregate has a first peak and a second peak, the fiber aggregate is composed of a first aggregate having the first peak and a second aggregate having the second peak, the average fiber diameter of the first aggregate is 1000 nm or more and 2000 nm or less, and the average fiber diameter of the second aggregate is 4000 nm or more and 8000 nm or less, which is an insulating acoustic absorbent material.

[0032] The fiber diameter according to this embodiment is obtained by photographing multiple locations of the fiber assembly under magnification using a scanning electron microscope (TM3030Plus model, manufactured by Hitachi) and measuring the diameters of multiple fibers in each electron microscope photograph. In this embodiment, the fiber diameters of 20 fibers were measured in each of the electron microscope photographs taken at five locations of the fiber assembly. In other words, a total of 100 fiber diameters were measured, and the average fiber diameter is the average value of the 100 fiber diameters.

[0033] Furthermore, in the heat insulating sound absorbing material according to this embodiment, the thickness of the first assembly is thinner than the thickness of the second assembly, and the thickness ratio of the first assembly: the second assembly is 1:4 or less. This is to enhance the sound absorbing effect. Furthermore, by making the thickness ratio of the first assembly: the second assembly 1:9 or less, a higher sound absorbing effect can be obtained. These sound absorbing effects will be explained below. <Sound absorption effect>

[0034] In this embodiment, the sound absorption effect was evaluated by measuring the sound absorption coefficient. In other words, a higher sound absorption coefficient is evaluated as a higher sound absorption effect because the higher the sound absorption coefficient, the better the sound generated by the sound source is absorbed.

[0035] In this embodiment, several samples were created by changing the configuration of the first and second assemblies. Then, the sound absorption coefficients of the samples were measured to evaluate the sound absorption effect. The measurements were performed under the following conditions. Test method: JIS A 1405-2 "Measurement of sound absorption coefficient and impedance using an acoustic tube" Measurement method: Transfer function method Measurement equipment: Normal incidence sound absorption coefficient measurement system WinZac8 (Φ100) (manufactured by Nihon Acoustic Engineering Co., Ltd.) The shape, thickness, etc. of the sample were adjusted so as to fit into the measurement device.

[0036] The configurations of the first and second assemblies evaluated are shown in FIG. 5. That is, FIG. 5 is a list of samples according to this embodiment. In this embodiment, samples were prepared in which the thicknesses of the first and second assemblies and the placement position of the first assembly were changed (on the sound source side, on the opposite side of the sound source, or on both sides), and each was evaluated. In addition, for reference, measurements were performed on only the first assembly (Sample 7) and on Styrofoam (registered trademark) as a general insulation material (foamed resin material) (Sample 8).

[0037] Moreover, the aggregates shown on the left side of FIG. 5 (aggregates indicated by downward arrows in the figure; for example, the first aggregate in sample 1 and the second aggregate in sample 2) are the aggregates arranged on the sound source side. The numbers in parentheses shown to the right of the aggregates indicate the thickness of the aggregates (for example, the first aggregate is 10 mm and the second aggregate is 40 mm in sample 1). The bulk density of samples 1 to 7 is 0.02 g / cm 3 More than 0.05g / cm 3 The following adjustments were made:

[0038] Figures 6 to 13 show the sound absorption coefficient measurement results for Samples 1 to 8. Figure 6 shows the sound absorption coefficient measurement results for Sample 1, Figure 7 shows the sound absorption coefficient measurement results for Sample 2, Figure 8 shows the sound absorption coefficient measurement results for Sample 3, Figure 9 shows the sound absorption coefficient measurement results for Sample 4, Figure 10 shows the sound absorption coefficient measurement results for Sample 5, Figure 11 shows the sound absorption coefficient measurement results for Sample 6, Figure 12 shows the sound absorption coefficient measurement results for Sample 7, and Figure 13 shows the sound absorption coefficient measurement results for Sample 8. Note that in the sound absorption coefficient measurement results shown in Figures 6 to 13, the horizontal axis is frequency (Hz) and the vertical axis is absorption coefficient (0 to 1, with 1 being 100% absorption coefficient).

[0039] First, comparing sample 8 (Styrofoam) with samples 1 to 7 (thermal insulating sound absorbing materials according to the present embodiment), it is found that there is a large difference in sound absorption coefficient, with sample 8 having a significantly smaller sound absorption coefficient. In other words, it is found that the thermal insulating sound absorbing materials according to the present embodiment have superior sound absorbing performance to Styrofoam in all respects.

[0040] Looking at sample 7, which is one of samples 1 to 7 and contains only the first aggregate but no second aggregate, the absorption rate drops in the high frequency range (2000 to 4000 Hz).

[0041] However, for samples 1 to 6, which contain second assemblies in addition to first assemblies, the absorption rate is less likely to drop even in the high frequency band. In other words, it can be said that fiber assemblies in which the thickness of the first assemblies is 10 mm or less and the thickness of the second assemblies is 40 mm or more are less likely to drop in absorption rate in the high frequency band and have high absorption performance in all frequency bands.

[0042] In particular, the decrease in absorption rate is small for samples 4 to 6 in which the thickness of the first assembly is 5 mm. In other words, it can be said that the fiber assemblies in which the thickness of the first assembly is 5 mm or less and the thickness of the second assembly is 45 mm or more are less likely to decrease in absorption rate in the high frequency band, and have higher absorption performance in all frequency bands.

[0043] Looking at the numerical values ​​more specifically, it can be said that for Samples 4 to 6, the absorptance is 0.6 or more at frequencies of 400 Hz or more, and the absorptance is 0.85 or more at frequencies of 1000 Hz or more and 5000 Hz or less.

[0044] The term "all frequency bands" used here refers to the frequency band from 100 Hz to 5000 Hz, which is the measurement range of the normal incidence sound absorption coefficient measurement system WinZac8 (Φ100) (manufactured by Nihon Onkyo Engineering Co., Ltd.), which is the measurement device. <About the heat insulating effect>

[0045] In this embodiment, the thermal insulation effect was evaluated by measuring the thermal conductivity. That is, the lower the thermal conductivity, the slower the heat transfer, so the lower the thermal conductivity, the higher the insulation effect.

[0046] The samples were the same as those used to evaluate the sound absorbing effect, but were shaped to fit the measuring device. Thermal conductivity was measured under the following conditions. Test method: JIS A 1412-2 "Method of measuring thermal resistance and thermal conductivity of thermal insulation materials" Measurement method: heat flow meter method Measuring device: HC-074 / 200 (manufactured by Hideko Seiki)

[0047] 14 is a diagram showing a list of the thermal conductivity measurement results. As can be seen from this, the thermal conductivity of sample 8 (Styrofoam) is 0.038, and the thermal insulation sound-absorbing material according to the present embodiment is 0.034 or 0.035. In other words, it is understood that the thermal insulation sound-absorbing material according to the present embodiment has a higher thermal insulation effect than Styrofoam.

[0048] In this measurement, the sound source side shown in Fig. 5 was placed on the high temperature side of the measurement device, and the opposite side of the sound source was placed on the low temperature side of the measurement device. In other words, the sound source side shown in Fig. 5 was placed on the high temperature side of the thermal conductivity measurement, and the opposite side was placed on the low temperature side of the thermal conductivity measurement. <Mold resistance>

[0049] Next, mold resistance is evaluated. In a humid climate like Japan, mold grows everywhere, for example, in bathrooms, kitchens, interior walls, leather products, etc. Naturally, mold can grow on heat insulating sound absorbing materials. If mold grows on a heat insulating sound absorbing material, it is highly likely that the performance of the heat insulating sound absorbing material will be reduced.

[0050] In this embodiment, therefore, the mold resistance of the fiber assembly was evaluated by the following test method. Test method: 1JIS Z 2911 (wet) "Testing of textile products" 2JIS Z 2911 (Method A) "Testing methods for plastic products"

[0051] Figure 15 shows the results of the mold resistance test. Figure 15a shows the test results according to test method 1 "Testing for textile products," and Figure 15b shows the test results according to test method 2 "Testing for plastic products."

[0052] As a result of the test, no mold growth was observed in either case, confirming the resistance to mold, and the mold growth in both cases was judged to be 0 (hereafter referred to as mold judgement 0). A mold judgement of 0 means that "no growth of mycelium was observed in the area where the sample or sample piece came into contact." <Effectiveness of this embodiment>

[0053] In this embodiment, the insulating sound-absorbing material is a resin fiber aggregate in which the fibers are irregularly and intricately entangled with each other and have spaces between the fibers, and the fiber diameter distribution of the fiber aggregate has a first peak and a second peak, the fiber aggregate is composed of a first aggregate having the first peak and a second aggregate having the second peak, the average fiber diameter of the first aggregate is 1000 nm or more and 2000 nm or less, and the average fiber diameter of the second aggregate is 4000 nm or more and 8000 nm or less.

[0054] By doing so, it is possible to provide a heat-insulating sound-absorbing material having high sound-absorbing and heat-insulating effects. The effectiveness of this will be described below.

[0055] First, the sound absorbing effect will be described. The first assembly has the characteristic of absorbing mainly low frequency bands (several hundred Hz to about 1000 Hz). When the frequency of a sound is low, the angular frequency becomes small, and when the angular frequency becomes small, the kinetic energy of the sound becomes small. When the kinetic energy becomes small, in a sound absorbing material with a large fiber diameter, the fibers stop vibrating when they come into contact with the sound absorbing material, making it difficult for the fibers to absorb the kinetic energy.

[0056] However, the first aggregate is an aggregate of fine fibers having an average fiber diameter of 1000 nm to 2000 nm. In other words, these fine fibers can absorb small kinetic energy in the low frequency range, making it possible to absorb low frequency sounds.

[0057] In addition, the fact that the fibers are irregularly and intricately entangled and that the resin fiber aggregate has spaces between them also works effectively. In other words, as sound penetrates into the spaces between the countless fibers, many fibers come into contact with the sound and absorb its kinetic energy, and the intricately entangled fibers disperse and absorb the kinetic energy, making it possible to efficiently absorb sound in this frequency range (low frequency range).

[0058] However, in the first assembly, the kinetic energy of sound increases at frequency bands higher than the low frequency band, and the kinetic energy cannot be completely absorbed, resulting in a decrease in sound absorption performance.

[0059] On the other hand, the second assembly has a large fiber diameter and is capable of absorbing high kinetic energy, i.e., the second assembly is capable of absorbing kinetic energy even in a high frequency band equal to or higher than the low frequency band.

[0060] And, like the first assembly, the second assembly allows sound to penetrate into the spaces between the countless fibers, causing many of the fibers to come into contact with the sound and absorb its kinetic energy, and the intricately entangled fibers disperse and absorb the kinetic energy, making it possible to efficiently absorb sound in such frequency ranges (frequency ranges higher than the low frequency range).

[0061] In other words, the insulating sound-absorbing material of this embodiment is a resin fiber aggregate in which the fibers are irregularly and intricately entangled with each other, with spaces between the fibers, and the fiber aggregate is composed of a first aggregate that absorbs low frequency bands and a second aggregate that absorbs higher frequency bands than the low frequency bands, thereby achieving a high sound absorption effect.

[0062] Regarding the heat insulating effect, the heat insulating and absorbing material in this embodiment is a fiber aggregate of resin in which the fibers are irregularly and intricately entangled with each other and have spaces between the fibers, and has a bulk density of 0.05 g / cm 3 The following factors enhance the heat insulating effect.

[0063] In other words, it has a structure with countless spaces between the fibers, and its bulk density is 0.05 g / cm 3 Because the temperature is low at or below this level, it contains a lot of air inside, which provides a high level of insulation close to that of air.

[0064] In this embodiment, the thickness of the first aggregate in the fiber aggregate is smaller than the thickness of the second aggregate.

[0065] As described above, the first assembly has the characteristic of absorbing sound mainly in the low frequency range (several hundred Hz to about 1000 Hz). And, even if its thickness (amount) is smaller than that of the second assembly, it is still capable of absorbing sound.

[0066] In contrast, the second assembly has the characteristic of absorbing higher frequencies than the low frequency band, but in order to obtain a sufficient sound absorption effect, its thickness (volume) must be greater than that of the first assembly. In other words, by making the thickness of the first assembly thinner than that of the second assembly, a high sound absorption effect can be obtained over the entire frequency range of the sound source.

[0067] In other words, this state can be expressed in terms of the relationship between the average fiber diameter and the median fiber diameter of the fiber aggregate, and the average fiber diameter of the fiber aggregate can be said to be smaller than the median fiber diameter of the fiber aggregate. This is because the second aggregate has a larger thickness (amount) ratio than the first aggregate, and therefore the median fiber diameter is closer to the average fiber diameter of the second aggregate than the average fiber diameter of the fiber diameters.

[0068] In addition, the ratio of the thickness of the first assembly to the thickness of the second assembly is set to 1:4 or less. Furthermore, the ratio of the thickness of the first assembly to the thickness of the second assembly is set to 1:9 or less.

[0069] By doing so, as described above, a high sound absorbing effect can be obtained in the entire frequency band of the sound source.

[0070] In addition, the bulk density of the fiber assembly is 0.05 g / cm 3 The following was determined.

[0071] By doing so, it is possible to provide a heat insulating sound absorbing material having a high heat insulating effect as described above.

[0072] In addition, the sound absorption coefficient of the fiber assembly is 0.6 or more at frequencies of 400 Hz or more, and 0.85 or more at frequencies of 1000 to 5000 Hz, and the thermal conductivity of the fiber assembly is 0.035 W / m·k or less.

[0073] By indicating specific values ​​for sound absorption coefficient and thermal conductivity, it is possible to provide a heat-insulating sound-absorbing material that combines high sound absorption and high thermal insulation effects.

[0074] In addition, the mold judgment of the fiber aggregate was determined to be 0. This is largely due to the characteristics of the heat insulating sound absorbing material according to this embodiment.

[0075] First, as described above, the heat insulating sound absorbing material according to this embodiment is made of almost 100% polypropylene, and no unnecessary substances such as additives are added. In other words, there is no substance that can be a nutrient for mold.

[0076] Next, the heat insulating sound absorbing material according to this embodiment has a high water repellency due to its structure, material, etc. The heat insulating sound absorbing material according to this embodiment corresponds to Class 5 (wet, no water droplets) according to a water repellency test conforming to JIS L 1092. In other words, due to the water repellency, the heat insulating sound absorbing material according to this embodiment does not have the moisture necessary for mold growth, creating an environment in which mold cannot grow.

[0077] Furthermore, this behavior in response to moisture is different from that of "glass wool," which is also known as an insulating material. Generally, "glass wool" is considered weak against moisture, and it is said that when condensation or rainwater leaks occur in a building, it absorbs the moisture and becomes unusable.

[0078] However, the heat-insulating sound-absorbing material according to this embodiment has a water-repellent effect, and therefore does not absorb moisture even in environments where it is exposed to moisture, and can therefore be used without problems.

[0079] In other words, the insulating sound-absorbing material of this embodiment does not contain impurities such as additives and has a water-repellent effect, so even if mold occurs, the mold cannot grow and there is no damage from the mold.

[0080] The fiber assembly is used as a heat insulating and sound absorbing material for tents. Tents are often folded up and transported in a compact form, and their outer shape is easily deformed by wind and the like.

[0081] In the case of foamed resin heat-insulating sound-absorbing materials, the shape is not easily changeable, so they could not be used in applications where the external shape is deformed, such as tents. In other words, there are few materials suitable for use as heat-insulating sound-absorbing materials for tents, and heat-insulating sound-absorbing materials have rarely been used in tents.

[0082] However, there is a great demand for insulating and sound-absorbing materials for tents. Examples include insulating and sound-absorbing materials for noise control in tents that cover buildings during demolition work, and insulating and sound-absorbing materials for making it comfortable to stay inside large tents, such as those used for glamping.

[0083] As described above, the heat insulating sound absorbing material according to the present embodiment has a high sound absorbing effect and a high heat insulating effect, and is a fiber aggregate, so its shape can be freely changed, and there is no problem with workability. Therefore, it can be said to be a heat insulating absorbing material suitable for tents.

[0084] However, although the heat insulating sound absorbing material according to the present embodiment is suitable for tents, other uses are not denied. Naturally, it can also be provided as a heat insulating sound absorbing material having high sound absorbing effect and high heat insulating effect as a heat insulating sound absorbing material for houses, vehicles, electronic devices, etc. ===Other embodiments===

[0085] The above-mentioned embodiment is for the purpose of facilitating understanding of the present invention, and is not intended to limit the present invention. The present invention can be modified and improved without departing from the spirit of the present invention, and it goes without saying that the present invention includes equivalents thereof.

[0086] In the above embodiment, polypropylene is used as the material of the fiber assembly, but this is not limiting, and other resins such as polyethylene (PE) and polyethylene terephthalate (PET), which are polyolefins, may be used.

Claims

1. A fiber aggregate of a resin in which the fibers are irregularly and intricately entangled with each other and have spaces between the fibers, The fiber diameter distribution of the fiber assembly has a first peak and a second peak, the fiber aggregate is composed of a first aggregate having the first peak and a second aggregate having the second peak, A heat-insulating sound-absorbing material, characterized in that the average fiber diameter of the first aggregate is 1000 nm or more and 2000 nm or less, and the average fiber diameter of the second aggregate is 4000 nm or more and 8000 nm or less.

2. 2. The heat insulating sound absorbing material according to claim 1, A heat-insulating sound-absorbing material, characterized in that the thickness of the first aggregate in the fiber aggregate is thinner than the thickness of the second aggregate.

3. The heat insulating sound absorbing material according to claim 2, A heat-insulating sound-absorbing material, characterized in that the ratio of the thickness of the first assembly to the thickness of the second assembly is 1:4 or less.

4. The heat insulating sound absorbing material according to claim 3, A heat-insulating sound-absorbing material, characterized in that the ratio of the thickness of the first assembly to the thickness of the second assembly is 1:9 or less.

5. The heat insulating sound absorbing material according to any one of claims 1 to 4, The bulk density of the fiber assembly is 0.05 g / cm ３ A heat insulating sound absorbing material characterized by the following:

6. The heat insulating sound absorbing material according to claim 5, A heat-insulating sound-absorbing material characterized in that the sound absorption coefficient of the fiber aggregate is 0.6 or more at frequencies of 400 Hz or more and 0.85 or more at frequencies of 1000 to 5000 Hz, and the thermal conductivity of the fiber aggregate is 0.035 W / m・k or less.

7. The heat insulating sound absorbing material according to claim 5, A heat insulating sound absorbing material, characterized in that the mold evaluation of the fiber assembly is 0.

8. The heat insulating sound absorbing material according to claim 5, A heat insulating and sound absorbing material, characterized in that the fiber assembly is used as a heat insulating and sound absorbing material for a tent.

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