Sound-absorbing material

Abstract

To provide a sound-absorbing material that allows for diverse design expression and exhibits excellent sound absorption even when thin. [Solution] A sound-absorbing material comprising a resin-containing surface layer, a metallic porous layer, and a breathable layer, wherein pores are formed in the surface layer.

Description

[Technical Field]

[0001] This disclosure relates to sound-absorbing materials. [Background technology]

[0002] In residential environments such as houses and offices, and in means of transportation such as aircraft, vehicles, and automobiles, sound-absorbing materials made of foams such as polyurethane foam and polyethylene foam containing an air layer, felt, nonwoven fabrics, and other fibrous materials are widely used for purposes such as blocking external noise and preventing internal sound from leaking out.

[0003] Conventional sound-absorbing materials are known, such as those described in Patent Document 1. Patent Document 1 describes a nonwoven fabric with an air permeability of 1 cc / cm². 2 / sec or more 30cc / cm 2 The first layer has a breathability of less than / sec and an air permeability of 30cc / cm². 2 / sec or more 1000cc / cm 2 A second layer made of nonwoven fabric with a permeability of 1 cc / cm² and having a permeability of 5 times or more the permeability of the first layer, and a second layer having a permeability of 1 cc / cm² or less. 2 / sec or more 30cc / cm 2 A third layer having a permeability of less than / sec and an air permeability of 0.5 to 2 times the air permeability of the first layer, and an air permeability of 30 cc / cm 2 / sec or more 1000cc / cm 2 The present invention describes a sound-absorbing material comprising a laminate in which a fourth layer, having a breathability of less than / sec and an air permeability of at least five times that of the third layer, is laminated in this order, and the second and fourth layers are polyurethane foam. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-192983 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The sound-absorbing material described in Patent Document 1 has the problem that its visible surface is "simply a nonwoven fabric" and lacks aesthetic appeal, and also that it is too thick at approximately 40 mm.

[0006] One embodiment of this disclosure aims to solve the problem of providing a sound-absorbing material that allows for diverse design expressions and has excellent sound absorption properties even when thin. [Means for solving the problem]

[0007] The means for solving the above problems include the following embodiments. <1> A sound-absorbing material comprising a resin-containing surface layer, a metallic porous layer, and a breathable layer, wherein pores are formed in the surface layer. <2> The surface layer comprises at least one selected from the group consisting of polyvinyl chloride resin, ABS resin, acrylic resin, urethane resin, polyolefin resin, polyamide resin, and polyester resin. <1> The sound-absorbing material described above. <3> The spacing between the holes is 20 mm or less. <1> or <2> The sound-absorbing material described above. <4> The diameter of the aforementioned hole is 0.1 mm to 3 mm. <1> ~ <3> Sound-absorbing material as described in any one of the following. <5> The metallic porous layer includes at least one selected from the group consisting of iron, stainless steel, galvanized wire, zinc, tin, chromium, brass, bronze, phosphor bronze, copper, Monel, nickel, titanium, aluminum, molybdenum, and tungsten. <1> ~ <4> Sound-absorbing material as described in any one of the following. <6> The aforementioned ventilation layer is a layer consisting of an air layer, glass wool, rock wool, gypsum board, or resin foam. <1> ~ <5> Sound-absorbing material as described in any one of the following. <7> The thickness of the aforementioned ventilation layer is 10 mm to 35 mm. <1> ~ <6> Sound-absorbing material as described in any one of the following. <8> The total thickness of the sound-absorbing material is less than 40 mm. <1> ~ <7> Sound-absorbing material as described in any one of the following. [Effects of the Invention]

[0008] According to one embodiment of the present disclosure, a sound-absorbing material is provided that allows for a wide range of design expressions and has excellent sound absorption properties even when thin. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view showing an example of a sound-absorbing material related to this disclosure. [Figure 2] This is a schematic diagram showing an example of a frame used to form an air layer. [Modes for carrying out the invention]

[0010] The embodiments of this disclosure are described below. The description is illustrative and does not limit the scope of this disclosure.

[0011] In this specification, numerical ranges indicated using "~" represent a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described stepwise within this specification, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described stepwise. Furthermore, in numerical ranges described within this specification, the upper or lower limit of that range may be replaced with the values ​​shown in the examples.

[0012] In this specification, when embodiments are described with reference to the drawings, the configuration of the embodiments is not limited to the configuration shown in the drawings. Furthermore, the sizes of the members in each figure are conceptual, and the relative relationships between the sizes of the members are not limited thereto.

[0013] In this specification, each component may contain a plurality of corresponding substances. When referring to the amount of each component in a composition, if there are a plurality of substances corresponding to each component in the composition, unless otherwise specified, it means the total amount of the plurality of substances present in the composition.

[0014] (Sound-absorbing material) The sound-absorbing material according to the present disclosure includes a skin layer containing a resin, a metallic porous layer, and a ventilation layer, and holes are formed in the skin layer.

[0015] As described above, the conventional sound-absorbing material has problems such as a lack of design in the visible surface and being too thick. Since the sound-absorbing material according to the present disclosure has a skin layer containing a resin, various design expressions are possible. Also, due to the layer structure and the formation of holes in the skin layer, it can be made into a sound-absorbing material with excellent sound absorption even if it is thin.

[0016] FIG. 1 is a schematic cross-sectional view showing an example of the sound-absorbing material according to the present disclosure. The sound-absorbing material 10 shown in FIG. 1 is a laminate in which a skin layer 12, a metallic porous layer 14, and a ventilation layer 16 are laminated, and the skin layer 12 has a plurality of holes 18 penetrating the skin layer 12. Also, the skin layer 12 is a layer containing a resin and may have a design layer (not shown) according to a desired design. Furthermore, the sound-absorbing material 10 may have an adhesive layer (not shown) between each layer in order to bond each layer.

[0017] <Skin layer> The sound-absorbing material according to the present disclosure includes a skin layer containing a resin, and holes are formed in the skin layer. The resin contained in the skin layer is not particularly limited, and examples thereof include vinyl chloride resin, acrylonitrile-butadiene-styrene (ABS) resin, acrylic resin, urethane resin, polyolefin resin, polyamide resin, polyester resin, and the like. Furthermore, the surface layer may contain a coloring agent. There are no particular restrictions on the coloring agent, and known coloring agents can be used as desired. When a design layer, which will be described later, is present, examples include carbon black.

[0018] From the viewpoint of aesthetics, the surface layer may be a layer on which a desired design is printed, or it may have a design layer. If there is a design layer, there are no particular restrictions on its position, but for example, the surface layer is preferably composed of three layers: a resin layer, a design layer, and another resin layer. The design of the surface layer is not particularly limited and can be selected as desired. Specific examples of designs include wood grain, geometric patterns, sand patterns, marble patterns, and so on. The material of the design layer is not particularly limited, and examples include a layer made of ink.

[0019] The surface layer has pores, and it is preferable that multiple pores are formed in it from the viewpoint of sound absorption and breathability. Furthermore, from the viewpoint of sound absorption and breathability, the holes in the epidermal layer are preferably through holes that penetrate the epidermal layer, and more preferably through holes that penetrate the epidermal layer in the thickness direction. The pores in the epidermal layer may be arranged in a two-dimensional manner, for example, by being arranged in a two-dimensional manner at an arbitrary angle or pattern. The spacing between the holes in the epidermal layer is preferably 20 mm or less, more preferably 10 mm or less, and even more preferably 1 mm to 10 mm, from the viewpoint of sound absorption, breathability, and design. The spacing between the holes is the distance between the centers of the holes in the planar direction of the epidermal layer. The diameter of the pores in the epidermal layer is preferably 0.1 mm to 3 mm, and more preferably 0.5 mm to 2 mm, from the viewpoint of sound absorption, breathability, and design.

[0020] The surface layer may have irregularities on the side opposite to the metallic porous layer. The depth of the recesses in the aforementioned irregularities is preferably 5 μm to 150 μm.

[0021] The thickness of the surface layer is preferably 30 μm to 300 μm, and more preferably 30 μm to 200 μm, from the viewpoint of durability and the ability to maintain unevenness.

[0022] The method for forming the surface layer is not particularly limited, and known sheet forming methods can be used. Examples include extrusion, calendering, and casting. Furthermore, the epidermal layer may be formed using a commercially available film.

[0023] <Metallic porous layer> The sound-absorbing material relating to this disclosure comprises a metallic porous layer. As the metallic porous layer, a known metallic porous material can be used, for example, in the form of a mesh or a wire mesh. The metallic porous layer has sound absorption and breathability due to being a porous material. As the material for the metallic porous layer, any known metal can be appropriately selected, taking into consideration its lightweight properties. Specifically, examples of preferred materials include iron, stainless steel, galvanized wire, zinc, tin, chromium, brass, bronze, phosphor bronze, copper, Monel, nickel, titanium, aluminum, molybdenum, and tungsten. As the metallic porous layer, for example, a porous body formed by sintering aluminum alloy powder (e.g., Calm A material (product name) manufactured by NDC Sales Co., Ltd.) can be used. Furthermore, the metallic porous layer may be colored by painting. The size of the pores in the porous material of the metallic porous layer is not particularly limited and can be appropriately selected according to desired properties such as sound absorption.

[0024] The thickness of the metallic porous layer is preferably 1 mm to 5 mm, and more preferably 1.4 mm to 3 mm, from the viewpoint of weight reduction and thinning.

[0025] <Ventilation layer> The sound-absorbing material relating to this disclosure includes a ventilation layer. The material of the ventilation layer is not particularly limited as long as it is breathable, but from the viewpoint of sound absorption, breathability, weight reduction, and thinning, the ventilation layer is preferably made of an air layer, glass wool, rock wool, gypsum board, or resin foam.

[0026] The thickness of the aforementioned ventilation layer is preferably about 30 mm, more preferably 10 mm to 35 mm, and more preferably 20 mm to 30 mm, from the viewpoint of sound absorption and thinness. Furthermore, if the ventilation layer is an air layer, the thickness of the ventilation layer is preferably about 50 mm from the viewpoint of sound absorption. The aforementioned air layer is preferably formed using a frame having voids. There are no particular restrictions on the material of the frame, but wood, iron, aluminum, resin, etc. can be selected as appropriate.

[0027] <Adhesive layer> The sound-absorbing material according to this disclosure may further have adhesive layers between each layer (between the surface layer and the metallic porous layer, between the metallic porous layer and the ventilation layer, etc.) in order to bond each layer together. There are no particular restrictions on the material of the adhesive layer; known adhesives can be used, and examples of preferred adhesives include acrylic adhesives, urethane adhesives, and polyester adhesives.

[0028] The thickness of the adhesive layer is not particularly limited, but from the viewpoint of durability, weight reduction, and thinness, it is preferably 5 μm to 100 μm, and more preferably 10 μm to 50 μm.

[0029] <Other layers> The sound-absorbing material relating to this disclosure may further have other layers besides those described above. Other layers are not particularly limited and may include known layers. For example, they may include an adhesive layer or a bonding layer. Known adhesive layers can be used as the adhesive layer. The aforementioned adhesive layers can be used as the bonding layer. Furthermore, a protective layer (protective sheet) may be included to protect the adhesive layer or bonding layer until use. Examples of protective sheets include polypropylene (PP) resin sheets.

[0030] The total thickness of the sound-absorbing material relating to this disclosure is preferably less than 60 mm, more preferably less than 40 mm, and even more preferably 10 mm or more and less than 40 mm. [Examples]

[0031] The embodiments of this disclosure will be described in more detail below with reference to examples, but the embodiments of this disclosure are not limited to the following examples.

[0032] (Example 1) <Step A: Epidermal layer formation> 100 kg of polyvinyl chloride resin (Kanevinyl S1008 (product name), manufactured by Kaneka Corporation) and 2 kg of pigment (carbon black) were heated to 180°C and mixed. The mixture was then formed into a sheet using the calendering method so that the thickness after drying would be 80 μm. Next, a printing ink containing acrylic resin (VTP-NT (product name), manufactured by DIC Graphics Co., Ltd.) was applied to the side of the molded sheet where the metallic porous layer is formed, and a design layer with a thickness of 5 μm after drying was formed to create sheet A. Next, 100 kg of polyvinyl chloride resin (Kanevinyl S1008 (product name), manufactured by Kaneka Corporation) was heated to 180°C and formed into a sheet using the calendering method so that the thickness after drying would be 80 μm, thereby forming sheet B. Sheet A, which has a design layer formed on it, and sheet B were heat-pressed together to form a surface layer.

[0033] <Process B: Adhesive layer formation> An adhesive was applied to the side of the surface layer where the metallic porous layer is formed, and after drying, an adhesive layer with a thickness of 35 μm was formed. The adhesive used was Semedine PM165-R (trade name), manufactured by Semedine Co., Ltd.

[0034] <Process C: Attachment of Adhesive Layer Protection Sheet> A polypropylene (PP) resin sheet (manufactured by Fujicolor Co., Ltd., BK0A (trade name), thickness: 60 μm) was attached to the adhesive layer to form a laminate of the skin layer and the adhesive layer protection sheet.

[0035] <Process D: Hole Formation> With respect to the obtained laminate, on the mold table, using a mold equipped with a cylindrical punching pin (diameter of the hole of the punching pin: 2.0 mm), holes penetrating the laminate were formed. The interval between the formed holes was 10 mm, and the diameter (hole diameter) of the formed holes was 2.0 mm.

[0036] <Process E: Preparation of Metallic Porous Layer> As the metallic porous layer, a metallic porous body with a thickness of 2 mm (Calm A material (trade name), manufactured by NDC Sales Co., Ltd.) was prepared.

[0037] <Process F: Preparation of Ventilation Layer> As the ventilation layer, glass wool with a thickness of 30 mm (GW64k (trade name), manufactured by Sonolize Co., Ltd.) was prepared. The density of the glass wool was 64k. k represents an index of how much weight (density) there is when the heat insulating material is packed in a box of 1 m 3 (1 m × 1 m × 1 m).

[0038] <Process G: Sound Absorbing Material Formation> The adhesive layer protection sheet was peeled off from the laminate in which holes were formed in Process D. The metallic porous layer was attached to and laminated on the laminate from which the adhesive layer protection sheet was peeled off. An adhesive (Semedine PM165-R (trade name), manufactured by Semedine Co., Ltd.) was applied to the side of the metallic porous layer of the obtained laminate on which the ventilation layer was to be formed so that the dried thickness would be 35 μm to form an adhesive layer. Next, the breathable layer was laminated onto the adhesive layer to obtain the sound-absorbing material of Example 1.

[0039] (Example 2) The sound-absorbing material for Example 2 was manufactured in the same manner as in Example 1, except that the spacing between the holes in step D was set to 20 mm.

[0040] (Example 3) The sound-absorbing material of Example 3 was manufactured in the same manner as in Example 1, except that the spacing of the holes in step D of Example 1 was set to 15 mm.

[0041] (Example 4) The sound-absorbing material of Example 4 was manufactured in the same manner as in Example 1, except that the spacing of the holes in step D of Example 1 was set to 3 mm.

[0042] (Example 5) The sound-absorbing material of Example 5 was manufactured in the same manner as in Example 1, except that the diameter of the hole in step D of Example 1 was set to 0.1 mm.

[0043] (Example 6) The sound-absorbing material of Example 6 was manufactured in the same manner as in Example 1, except that the diameter of the hole in step D of Example 1 was set to 3.0 mm.

[0044] (Example 7) The sound-absorbing material of Example 7 was prepared in the same manner as in Example 1, except that the thickness of the surface layer in step A was set to 30 μm.

[0045] (Example 8) The sound-absorbing material of Example 8 was prepared in the same manner as in Example 1, except that the thickness of the surface layer in step A of Example 1 was set to 300 μm.

[0046] (Example 9) The sound-absorbing material of Example 9 was prepared in the same manner as in Example 1, except that 100 kg of polyvinyl chloride resin (Kanevinyl S1008 (trade name), manufactured by Kaneka Corporation), which is the material for the surface layer in step A of Example 1, was replaced with 100 kg of ABS resin (SE-10 (trade name), manufactured by Denka Corporation).

[0047] (Example 10) The sound-absorbing material of Example 10 was prepared in the same manner as in Example 1, except that 100 kg of polyvinyl chloride resin (Kanevinyl S1008 (trade name), manufactured by Kaneka Corporation), which is the material for the surface layer in step A of Example 1, was replaced with 100 kg of acrylic resin (LG 2 (trade name), manufactured by Sumitomo Chemical Co., Ltd.).

[0048] (Example 11) The sound-absorbing material for Example 11 was prepared in the same manner as in Example 1, except that the material for the ventilation layer in step F of Example 1, which was 30 mm thick glass wool (GW64k (product name), manufactured by Sonorize Co., Ltd.), was replaced with 30 mm thick resin foam (Acousticell (product name), manufactured by Unix Co., Ltd.).

[0049] (Example 12) The sound-absorbing material for Example 12 was prepared in the same manner as in Example 1, except that the material for the ventilation layer in step F of Example 1, which was 30 mm thick glass wool (GW64k (product name), manufactured by Sonorize Co., Ltd.), was replaced with 30 mm thick rock wool (TK2602-S (product name), manufactured by Daiken Corporation).

[0050] (Example 13) The sound-absorbing material of Example 13 was manufactured in the same manner as in Example 1, except that the 30 mm thick glass wool (GW64k (product name), manufactured by Sonorize Co., Ltd.), which is the material for the ventilation layer in step F of Example 1, was replaced with a 50 mm thick air layer using the wooden frame shown in Figure 2.

[0051] (Example 14) The sound-absorbing material of Example 14 was manufactured in the same manner as in Example 1, except that the spacing of the holes in step D of Example 1 was set to 25 mm.

[0052] (Example 15) The sound-absorbing material of Example 15 was manufactured in the same manner as in Example 1, except that the diameter of the hole in step D of Example 1 was set to 4.5 mm.

[0053] (Comparative Example 1) <Process V: Epidermal layer preparation> A 2mm thick cloth (Istoflon (product name), manufactured by Sakane Sangyo Co., Ltd.) was prepared as the epidermal layer.

[0054] <Process W: Adhesive layer formation> In the same manner as in step B of Example 1, an adhesive was applied to the side of the surface layer in step V where the metallic porous layer is formed to form an adhesive layer.

[0055] <Step X: Preparation of metallic porous layer> A metallic porous layer was prepared in the same manner as in step E of Example 1.

[0056] <Process Y: Preparation of the ventilation layer> A ventilated layer was prepared in the same manner as in step F of Example 1.

[0057] <Process Z: Sound absorbing material formation> The adhesive layer and the metallic porous layer were laminated to form a laminate of the epidermal layer and the metallic porous layer. An adhesive layer (Cemedine PM165-R (product name), manufactured by Cemedine Co., Ltd.) was applied to the breathable layer side of the metallic porous layer of the obtained laminate to a thickness of 35 μm after drying, thereby forming an adhesive layer. Next, the breathable layer was laminated onto the adhesive layer to form Comparative Example 1, which has a layer structure of 2 mm for the surface layer, 2 mm for the metallic porous layer, and 30 mm for the breathable layer.

[0058] (Comparative Example 2) The sound-absorbing material for Comparative Example 2 was prepared in the same manner as in Example 1, except that the 2 mm thick metallic porous material (Calm A material (product name), manufactured by NDC Sales Co., Ltd.) in step E of Example 1 was replaced with a 2 mm thick metallic non-porous material.

[0059] (Comparative Example 3) The sound-absorbing material for Comparative Example 3 was prepared in the same manner as in Example 1, except that step D in Example 1 was omitted.

[0060] <Sound absorption evaluation> The sound absorption coefficient of the sound-absorbing materials in the examples and comparative examples was measured using the reverberation chamber method at the center frequency of a 1 / 3 octave band in accordance with JIS A 1409:1998. Based on the "maximum value of the reverberation chamber sound absorption coefficient" in the obtained frequency range, the following evaluation criteria were used. The higher the sound absorption coefficient, and the higher the maximum value of the reverberation chamber sound absorption coefficient, the better the sound absorption performance. Ranks A and B are considered to be at an acceptable level. A: 0.5 or higher B: 0.4 or higher, less than 0.5 C: Less than 0.4

[0061] <Design evaluation> The appearance of the obtained sound-absorbing material was evaluated. Specifically, the surface appearance of the sound-absorbing material was visually observed and evaluated by 10 workers. The evaluation criteria are shown below. Note that the appearance of the sound-absorbing material in Comparative Example 1 is considered the appearance of the conventional product. Ranks A and B are considered to be at an acceptable level. A: It has a superior design compared to conventional products, and the metallic porous layer is less noticeable. B: While it had a superior design compared to conventional products, the metallic porous layer was noticeable. C: The appearance was similar to that of conventional products and lacked aesthetic appeal.

[0062] The evaluation results are summarized in Table 1.

[0063] [Table 1]

[0064] As shown in Table 1, the sound-absorbing materials of Examples 1 to 15 allowed for a wider range of design expressions and exhibited superior sound absorption even at a thin thickness, compared to the sound-absorbing materials of Comparative Examples 1 to 3. [Explanation of symbols]

[0065] 10: Sound-absorbing material, 12: Surface layer, 14: Metallic porous layer, 16: Ventilation layer, 18: Holes, 30: Frame

Claims

1. Epidermal layer containing resin, A metallic porous layer, and Equipped with a ventilation layer, Pores are formed in the epidermal layer. Sound-absorbing material.

2. The sound-absorbing material according to claim 1, wherein the surface layer comprises at least one selected from the group consisting of polyvinyl chloride resin, ABS resin, acrylic resin, urethane resin, polyolefin resin, polyamide resin, and polyester resin.

3. The sound-absorbing material according to claim 1 or claim 2, wherein the spacing between the holes is 20 mm or less.

4. The sound-absorbing material according to claim 1 or claim 2, wherein the diameter of the hole is 0.1 mm to 3 mm.

5. The sound-absorbing material according to claim 1 or claim 2, wherein the metallic porous layer comprises at least one selected from the group consisting of iron, stainless steel, galvanized wire, zinc, tin, chromium, brass, bronze, phosphor bronze, copper, Monel, nickel, titanium, aluminum, molybdenum, and tungsten.

6. The sound-absorbing material according to claim 1 or claim 2, wherein the ventilation layer is a layer made of an air layer, glass wool, rock wool, gypsum board, or resin foam.

7. The sound-absorbing material according to claim 1 or claim 2, wherein the thickness of the ventilation layer is 10 mm to 35 mm.

8. The sound-absorbing material according to claim 1 or claim 2, wherein the total thickness of the sound-absorbing material is less than 40 mm.

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