Waterproof sound transmission member

Abstract

Provided is a waterproof sound-transmitting member that has high waterproofness and, even if compressed for use in order to prevent interference of sound inside a frame, has low sound loss, does not impair the sound characteristics of a microphone or a speaker, and can be suitably used for waterproof protection of a microphone or a speaker of an electrical product. The waterproof sound-transmitting member is provided with a less area of a waterproof sound-transmitting film, and the stress required to compress the waterproof sound-transmitting member by 40% in a direction perpendicular to the film surface of the waterproof sound-transmitting member is 1 to 600 kPa.

Description

Technical Field

[0001] This invention relates to a waterproof and sound-permeable component that minimizes acoustic loss due to compression during installation in a frame. Background Technology

[0002] Electrical / electronic products (hereinafter referred to as "electrical products", but also used in the sense of including electronic products) such as mobile phones, smartphones, smartwatches, cordless phones, portable media players, portable gaming devices, digital cameras, digital camcorders, and headphones have sound receiving parts and sound producing parts such as microphones and speakers in their frame structure, and openings are provided at positions corresponding to them, through which sound is transmitted.

[0003] As exemplified by the widespread adoption of smartphones, these electrical appliances are increasingly used in outdoor environments and indoor settings where water is required, leading to a desire for waterproof construction. For instance, waterproof features are becoming commonplace in smartphones.

[0004] Previously, waterproof and sound-permeable components were installed at the openings of the sound-producing and sound-receiving parts to prevent water from seeping into the frame and to minimize sound loss. The waterproof and sound-permeable component consisted of a waterproof and sound-permeable membrane and a support layer stacked around its periphery, with a sound-permeable area where the waterproof and sound-permeable membrane was exposed.

[0005] The support layer maintains the shape of the component or allows it to be joined to the frame. Sound passes through the waterproof and sound-permeable membrane in the sound-permeable area. Waterproof and sound-permeable components are sometimes used in electrical appliances in a compressed state to suppress water immersion and sound leakage from the interface with the frame.

[0006] By using soft materials and reducing the base weight of waterproof and sound-permeable membranes, sound loss in waterproof and sound-permeable components can be reduced. To reduce base weight, choosing lightweight materials or forming a porous structure is effective. However, waterproof and sound-permeable membranes with soft materials and porous structures are prone to deformation under compression.

[0007] Patent Document 1 discloses a waterproof and sound-permeable membrane that reduces sound loss by using a soft material such as polyurethane. Patent Document 2 discloses a waterproof and sound-permeable component that uses a soft material such as silicone rubber in its waterproof and sound-permeable membrane, so that sound loss does not increase when the pressure is restored to normal after water pressure is applied. Patent Document 3 discloses a waterproof and sound-permeable component that reduces the distortion of transmitted sound by using a polyolefin resin foam in the support layer of the waterproof and sound-permeable component.

[0008] Prior technical documents

[0009] Patent documents

[0010] Patent Document 1: WO2015 / 105052

[0011] Patent Document 2: Japanese Patent Application Publication No. 2014-7738

[0012] Patent Document 3: Japanese Patent Application Publication No. 2015-142282 Summary of the Invention

[0013] The problem that the invention aims to solve

[0014] Waterproof and sound-permeable membranes with soft, porous materials have low sound loss, but they are easily deformed by external forces. If such membranes are used in waterproof and sound-permeable components, they will deform when compressed and installed into a frame, increasing sound loss.

[0015] Waterproof and sound-permeable components using the soft material disclosed in Patent Document 1 are not suitable for fitting into frames with high compression ratios.

[0016] Patent Document 2 discloses a waterproof and sound-permeable membrane using a soft material. Under water pressure, the membrane deforms, but if normal pressure is restored, the deformation is eliminated, and the sound loss returns to its original state. However, it does not consider sound loss in structures where the waterproof and sound-permeable membrane is compressed and constantly subjected to pressure.

[0017] In the waterproof and sound-permeable component disclosed in Patent Document 3, which uses foam as the support layer, sound distortion caused by interference from the support layer is reduced. However, it focuses on dynamic viscoelasticity, such as the loss modulus and loss coefficient of the support layer, but does not consider flexibility. Furthermore, it does not consider the deformation of the waterproof and sound-permeable membrane during the compression assembly of the component.

[0018] The object of this invention is to provide a waterproof and sound-permeable component that can be used with a high compression ratio. Specifically, it aims to provide a waterproof and sound-permeable component that can be compressibly fitted into a frame even when using a waterproof and sound-permeable membrane made of a soft material with low acoustic loss, thereby suppressing overall acoustic loss to a low level.

[0019] Solution for solving the problem

[0020] The inventors conducted in-depth research and found that by studying the combination of the waterproof and sound-permeable membrane and the support layer, the stress required for the membrane surface to be compressed by 40% in the vertical direction relative to the waterproof and sound-permeable component is 1 to 600 kPa. When used at a high compression rate, this can reduce sound loss, thus completing the present invention.

[0021] That is, the present invention relates to the waterproof and sound-permeable components described below.

[0022] (1) A waterproof and sound-permeable component, wherein a support layer is stacked on at least one side of a waterproof and sound-permeable membrane, characterized in that it has a sound-permeable area exposed on both sides of the waterproof and sound-permeable membrane, and the stress required to compress 40% in a direction perpendicular to the membrane surface of the waterproof and sound-permeable membrane is 1 kPa to 600 kPa.

[0023] (2) The waterproof and sound-permeable component according to (1) is characterized in that a support layer is stacked on both sides of the waterproof and sound-permeable membrane.

[0024] (3) The waterproof and sound-permeable component according to (1) or (2) is characterized in that the support layer is composed of a single layer or multiple layers, and at least includes a layer of sheet material that uses a stress of less than 600 kPa required to compress 40% in the vertical direction.

[0025] (4) The waterproof and sound-permeable component according to (3) is characterized in that the sheet material for which the stress required to compress 40% in the vertical direction is less than 600 kPa comprises a sheet layer made of a porous synthetic resin material.

[0026] (5) The waterproof and sound-permeable component according to (4) is characterized in that the synthetic resin porous material is a porous material of synthetic resin selected from the group consisting of polyolefin resin, polyurethane resin and acrylic resin.

[0027] (6) The waterproof and sound-permeable component according to any one of (3) to (5), characterized in that the layer constituting the support layer uses a sheet material with a stress of less than 600 kPa required to compress 40% in the vertical direction, which accounts for more than 40% of the overall thickness of the waterproof and sound-permeable component.

[0028] (7) The waterproof and sound-permeable component according to any one of (1) to (6), characterized in that the tensile elastic modulus of the waterproof and sound-permeable membrane is 0.5 MPa to 20 MPa.

[0029] (8) The waterproof and sound-permeable component according to any one of (1) to (7), characterized in that the waterproof and sound-permeable membrane contains 100% of a material with a modulus of 1 MPa to 20 MPa.

[0030] (9) The waterproof and sound-permeable component according to any one of (1) to (8), characterized in that the waterproof and sound-permeable membrane is made of polyurethane resin.

[0031] (10) The waterproof and sound-permeable component according to any one of (1) to (9), characterized in that the area of ​​the support layer laminated on at least one side of the waterproof and sound-permeable membrane is 1 mm². 2 ~50mm 2 .

[0032] (11) The waterproof and sound-permeable component according to any one of (1) to (10) is characterized in that the planar shape of the sound-permeable area does not have corners and the roundness is 0.45 to 1.

[0033] (12) The waterproof and sound-permeable component according to any one of (1) to (11), characterized in that the area of ​​the sound-permeable region is 0.5 mm. 2 ~40mm 2 .

[0034] (13) The waterproof and sound-permeable component according to any one of (1) to (12) is characterized in that a support layer is laminated on the periphery of the waterproof and sound-permeable membrane.

[0035] The effects of the invention

[0036] A waterproof and sound-permeable component, consisting of a waterproof and sound-permeable membrane and a support layer, is compressed in its thickness direction (perpendicular to the membrane surface) when installed in a frame. The force applied by compression is applied to the waterproof and sound-permeable membrane through the support layer. If excessive force is applied to the waterproof and sound-permeable membrane, deformation occurs, hindering vibrations caused by incident sound, thereby increasing sound loss.

[0037] According to the present invention, by setting the stress required to compress the membrane surface of the waterproof and sound-permeable component by 40% in the vertical direction to below 600 kPa, the force applied to the waterproof and sound-permeable membrane when the waterproof and sound-permeable component is installed in the frame at a high compression rate can be reduced, thereby reducing sound loss. This technical effect can be achieved more reliably by optimally combining the materials of the support layer, the membrane, and the shape of the component.

[0038] That is, a membrane with a low tensile modulus of elasticity and easy deformation is used as a waterproof and sound-permeable membrane, and the supporting layer is also combined with a material with a certain thickness and low compressive stress, thereby preventing the increase of sound loss due to compression when installed in the frame. Attached Figure Description

[0039] Figure 1 This is a cross-sectional view of an example of the structure of the waterproof and sound-permeable component of the present invention.

[0040] Figure 2 This is a top view of an example of the structure of the waterproof and sound-permeable component of the present invention.

[0041] Figure 3 This is a schematic diagram of an acoustic measuring device.

[0042] Figure 4 This is a schematic diagram of a compression test. Detailed Implementation

[0043] The waterproof and sound-permeable component of the present invention is a waterproof and sound-permeable component formed by stacking a support layer on at least one side of a waterproof and sound-permeable membrane. The component is characterized in that it has a sound-permeable area with both sides of the waterproof and sound-permeable membrane exposed, and the stress required for 40% compression of the membrane surface in the vertical direction relative to the membrane surface of the waterproof and sound-permeable component is 1 to 600 kPa.

[0044] Figure 1 This illustrates an example of the structure of the waterproof and sound-permeable component of the present invention. According to... Figure 1 In the waterproof and sound-permeable component 1 of the present invention, the support layer 3 is stacked on both sides of the waterproof and sound-permeable membrane 2 in such a way that it is disposed at the periphery of the sound-permeable area 4.

[0045] 1. Waterproof and sound-permeable components

[0046] (1) Structure

[0047] The waterproof and sound-permeable component of the present invention comprises a waterproof and sound-permeable membrane and a support layer, wherein the support layer is laminated on at least a portion of at least one side of the waterproof and sound-permeable membrane. Furthermore, it has an area (i.e., a sound-permeable area) where the support layer is not laminated and both sides of the waterproof and sound-permeable membrane are exposed.

[0048] In the waterproof and sound-permeable component of the present invention, sound passes through the sound-permeable area. The incident sound causes the waterproof and sound-permeable membrane to vibrate and pass through to the opposite side. That is, in the waterproof and sound-permeable component of the present invention, a support layer is laminated on the portion of the waterproof and sound-permeable membrane outside the sound-permeable area.

[0049] (2) Compressive stress

[0050] The waterproof and sound-permeable component is compressed and installed into the frame in a direction perpendicular to the membrane surface (the thickness direction of the component). The force applied by compression is applied to the waterproof and sound-permeable membrane through the support layer. If excessive force is applied to the waterproof and sound-permeable membrane, deformation will occur, hindering the vibration caused by incident sound, thereby increasing sound loss.

[0051] In order to reduce the force applied to the waterproof and sound-permeable membrane and reduce sound loss when the waterproof and sound-permeable component is installed into the frame at a high compression rate, the stress required for the waterproof and sound-permeable component to be compressed by 40% in a direction perpendicular to the membrane surface of the waterproof and sound-permeable membrane needs to be less than 600 kPa, preferably less than 400 kPa, and more preferably less than 300 kPa.

[0052] On the other hand, by pressing and fixing the waterproof and sound-permeable component to the frame, the energy loss caused by the vibration of the waterproof and sound-permeable membrane is suppressed, and the sound loss is reduced. Therefore, the stress required for the waterproof and sound-permeable component to be compressed by 40% in a direction perpendicular to the membrane surface of the waterproof and sound-permeable membrane needs to be 1 kPa or more, preferably 20 kPa or more, and more preferably 40 kPa or more.

[0053] Figure 4This is a summary of the method for measuring compressive stress according to the present invention. Figure 4 In the figure, reference numeral 1 is a waterproof and sound-permeable component, reference numeral 17 is a parallel plate, and reference numeral 18 is the compression direction.

[0054] Generally, compression testing involves clamping a test piece between two parallel plates using a compression testing machine and applying a load to determine the stress. In this invention, the test piece (waterproof and sound-permeable component) is clamped with parallel plates such that the surfaces of the parallel plates are parallel to the surface of the waterproof and sound-permeable membrane. In this case, when the support layer of the waterproof and sound-permeable component is provided on both sides of the waterproof and sound-permeable membrane, the support layers on both sides are positioned in contact with the parallel plates. On the other hand, when the support layer of the waterproof and sound-permeable component is only provided on one side of the waterproof and sound-permeable membrane, both the waterproof and sound-permeable membrane and the support layer are positioned in contact with the parallel plates respectively.

[0055] Furthermore, by applying a compressive force to the membrane surface of the waterproof and sound-permeable membrane in the vertical direction, the parallel plates are moved in the vertical direction relative to the membrane surface of the waterproof and sound-permeable membrane, thereby narrowing the gap between the two parallel plates and applying a compressive force to the waterproof and sound-permeable component.

[0056] The stress required for 40% compression in this invention can be calculated by the following method: setting the thickness of the waterproof and sound-permeable component (the sum of the thicknesses of the support layer and the waterproof and sound-permeable membrane) to 100%, measuring the stress when its thickness is compressed by 40% (when the compressed thickness is reduced to 60% of the original thickness), and dividing by the area of ​​the support layer.

[0057] It should be noted that the area of ​​the support layer refers to the area of ​​the portion of the support layer in contact with the parallel plate of the compression testing machine, whether the support layer is a single layer or multiple support layers are stacked with a constant shape. However, when multiple support layers are stacked with non-constant shapes, the area is calculated based on the portion subjected to force during compression, i.e., the area of ​​the most overlapping portion of the multiple support layers when viewed from the vertical direction (the direction perpendicular to the membrane surface of the waterproof and sound-permeable membrane or the compression direction).

[0058] For example, if the outermost layer of the support layer (the layer in contact with the parallel plate) has a large area and the inner layers have small areas, stress is applied to the area of ​​the inner layers that overlap in the vertical direction, so the area of ​​the support layer becomes the area of ​​the inner layers. On the other hand, if the outermost layer of the support layer has a small area and the inner layers have a large area, stress is applied to the area of ​​the outermost layer, so the area of ​​the support layer becomes the area of ​​the outermost layer.

[0059] 2. Waterproof sound-permeable membrane

[0060] (1) Physical properties of membranes

[0061] The waterproof and sound-permeable membrane used in the waterproof and sound-permeable component of the present invention is a membrane that allows sound to pass through while blocking water from passing through, and at least a portion of it has a sound-permeable area. The more flexible the waterproof and sound-permeable membrane, the easier it is to vibrate, and the less sound loss there is. In the waterproof and sound-permeable membrane, the tensile modulus of elasticity, which is an indicator of its flexibility, is preferably 20 MPa or less, more preferably 10 MPa or less.

[0062] On the other hand, in order to reduce the deformation caused by the compression of the waterproof and sound-permeable components and thus reduce sound loss, the tensile elastic modulus of the waterproof and sound-permeable membrane is preferably 0.5 MPa or more, and more preferably 2 MPa or more.

[0063] To reduce the tensile modulus of elasticity of the waterproof and sound-permeable membrane, using a soft material is effective. The 100% modulus, an indicator of the material's softness, is preferably 1 to 20 MPa. The 100% modulus of the material is an intrinsic property of the material constituting the waterproof and sound-permeable membrane and is not affected by porous structures, etc. The 100% modulus of this invention is a value measured in a non-porous membrane obtained by dissolving the waterproof and sound-permeable membrane in a solvent and then drying it.

[0064] Furthermore, the water pressure resistance of the waterproof and sound-permeable membrane of the present invention, measured by the JIS L 1092B method (high water pressure method), is preferably 10 to 400 kPa, more preferably 30 to 400 kPa. When the water pressure resistance is in the range of 10 to 400 kPa, high sound permeability and waterproofness can be obtained.

[0065] The elongation at break of the waterproof and sound-permeable membrane is preferably 100-500%, more preferably 150-400%, and particularly preferably 80-260%. If the elongation at break is 100-500%, it can maintain good sound permeability and sufficient waterproofness.

[0066] The air permeability of the waterproof and sound-permeable membrane is preferably 3 to 500 seconds / 100 mL, more preferably 3 to 300 seconds / 100 mL, according to the JIS L 1096 Göllley method. A permeability of 3 to 500 seconds / 100 mL provides good sound permeability.

[0067] In addition, the waterproof and sound-permeable membrane of the present invention has sound permeability with a sound loss of less than 10dB at a frequency of 1kHz, less than 5dB at a frequency of 2kHz, and less than 5dB at a frequency of 5kHz.

[0068] (2) Membrane material

[0069] The material used to constitute the waterproof and sound-permeable membrane of the present invention is not particularly limited, but a relatively soft material as described above is preferred, and a soft synthetic resin that meets the above-mentioned 100% modulus range (1 to 20 MPa) is more preferred.

[0070] Specifically, elastomers such as polyurethane resin and silicone rubber are preferred. Furthermore, the waterproof and sound-permeable membrane becomes more flexible by being made into a porous membrane, therefore a porous structure is preferred. From the viewpoint of ease of structural control, a porous polyurethane resin membrane is more preferably used.

[0071] Examples of polyurethane resins include polyester-based polyurethanes, polyether-based polyurethanes, and polycarbonate-based polyurethanes. It is preferred to use at least one of them, but two or more can also be used in combination.

[0072] Here, polyurethane resin is a resin obtained by polymerizing isocyanate and polyol components.

[0073] Examples of isocyanate components include aliphatic diisocyanates, aromatic diisocyanates, and alicyclic diisocyanates, which can be used alone or in combination with two or more. Specific examples of aliphatic diisocyanates include 1,6-hexamethylene diisocyanate. Examples of aromatic diisocyanates include phenylenediamine diisocyanate, 4,4'-diphenylmethane diisocyanate, and toluene diisocyanate. Examples of alicyclic diisocyanates include 1,4-cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate. Additionally, isocyanates with three or more functionalities can be used as needed.

[0074] On the other hand, examples of polyol components include polyester polyols made from polyethylene adipate, polybutylene adipate, and polycaprolactone polyols; polycarbonate polyols made from polyhexamethylene carbonate; and polyether polyols made from polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Any one of these can be used, or a combination of two or more.

[0075] In addition, various additives can be added to the polyurethane resin as needed. Examples of additives include waterproofing agents, crosslinking agents, inorganic microparticles, plasticizers, antioxidants, ultraviolet absorbers, smoothing agents such as amide waxes, hydrolysis inhibitors, pigments, yellowing inhibitors, and matting agents.

[0076] The porous membrane made of synthetic resin is preferably formed by solidifying a synthetic resin solution containing synthetic resin and a water-soluble polar organic solvent in water. As a method for manufacturing this porous membrane, taking the aforementioned polyurethane resin as an example, the manufacturing method is as follows: a polyurethane resin solution containing polyurethane resin, inorganic particles, and a polar organic solvent is coated onto one side of a suitable release substrate, and then the coated polyurethane resin solution is immersed in water to solidify, thereby manufacturing a porous membrane.

[0077] Here, the polyurethane resin solution can contain inorganic particles with hydrophobic surfaces. Since these hydrophobic inorganic particles have a high affinity for polar organic solvents, they exist in the solution in a state where the polar organic solvent surrounds the hydrophobic inorganic particles, thus locally increasing the concentration of the polar organic solvent. Therefore, during the process of immersing the polyurethane resin solution in water to solidify the polyurethane resin, pores are formed around the hydrophobic inorganic particles. In this way, a porous membrane composed of polyurethane resin can be formed efficiently.

[0078] Examples of such inorganic particles include carbonates such as calcium carbonate and magnesium carbonate; silicates such as silicon dioxide and diatomaceous earth; silicates such as talc and zeolite; hydroxides such as aluminum hydroxide and magnesium hydroxide; sulfates such as barium sulfate and calcium sulfate; borates such as aluminum borate and zinc borate; titanates such as potassium titanate; metal oxides such as zinc oxide and titanium oxide; and carbonaceous materials such as carbon black.

[0079] These inorganic particles can be either porous or non-porous. Furthermore, the shape of the inorganic particles can be fixed or non-fixed, such as polygonal, needle-like, spherical, cubic, spindle-shaped, or plate-like, without particular limitation. One type of inorganic particle can be used alone, or two or more can be used in combination. Among these, calcium carbonate particles or silica particles are preferred because they adsorb large amounts of polar organic solvents such as N,N-dimethylformamide and easily form micropores.

[0080] The content of the aforementioned inorganic particles varies depending on their type and therefore cannot be generalized, but it is generally preferred to be 1 to 75% by mass relative to the total solids content of the polyurethane resin solution. Sufficient porosity can be obtained by setting the content to 1% by mass or more. Sufficient water resistance can be obtained by setting the content to 75% by mass or less, maintaining the strength, particularly tensile strength, of the obtained microporous membrane. The content of inorganic particles relative to the total solids content of the polyurethane resin solution is preferably 3 to 40% by mass.

[0081] Examples of polar organic solvents include N,N-dimethylformamide and N,N-dimethylacetamide.

[0082] The waterproof and sound-permeable membrane of the preferred embodiment can be manufactured, for example, by coating a polyurethane resin solution containing a synthetic resin as the main body of polyurethane resin, inorganic microparticles in a weight ratio of 1 to 75% by mass relative to the total solids content, and a polar organic solvent onto a release substrate.

[0083] Methods for applying polyurethane resin solutions to release substrates include, for example, using floating blade coating machines, roller blade coating machines, comma blade coating machines, reverse coating machines, lip coating machines, roller coating machines, and mold coating machines.

[0084] The preferred coating amount of the polyurethane resin solution, based on the solid content, is 10–200 g / m². 2 More preferably 10–750 g / m 2 By setting the coating amount within this range, a porous membrane with a thickness of 10 to 150 μm can be obtained. That is, the thickness of the waterproof and sound-permeable membrane of the present invention is preferably 10 to 150 μm, more preferably 15 to 80 μm.

[0085] After applying the polyurethane resin solution to the release substrate, the polyurethane resin solution is then immersed in water at 10–40°C. During this process, water enters the interior of the polyurethane resin solution, and the polar organic solvent contained in the polyurethane resin solution is almost completely replaced by the water, thereby causing the polyurethane resin to solidify.

[0086] The immersion time in water is preferably 30 seconds to 10 minutes, more preferably 1 to 5 minutes. If the immersion time is less than 30 seconds, the polyurethane resin will not solidify completely, and sufficient pores may not be formed, thus failing to achieve waterproof and sound-permeable properties. If the immersion time exceeds 10 minutes, productivity will decrease.

[0087] Next, wash in warm water at 30–80°C for 3–15 minutes to remove residual polar organic solvents, and then heat-treat at 50–150°C for 1–10 minutes to dry. Then, remove the release substrate to form a porous membrane made of polyurethane resin.

[0088] The above-described method for manufacturing porous polyurethane resin membranes can also be applied to synthetic resins other than polyurethane resins. In this invention, polyurethane resin is suitable from the perspective of flexibility and ease of forming porous structures, but other synthetic resins can also be used to manufacture porous membranes using the same method.

[0089] The resulting porous membrane can be used for a post-treatment waterproofing process, thereby further improving water resistance. Examples of waterproofing agents used in this process include paraffin-based, silicone-based, and fluorine-based agents. Among these, fluorine-based agents are preferred from the viewpoint of imparting high water resistance. The waterproofing process can be performed using conventional methods such as filling or spraying.

[0090] In addition to the aforementioned porous polyurethane resin membranes, the waterproof and sound-permeable membrane used in this invention can also be a rubber-like elastomer (thermosetting elastomer (rubber-based)). There are no particular limitations on the rubber-like elastomer; any material possessing rubber-like elasticity can be used, such as silicone rubber, ethylene propylene diene monomer (EPDM), acrylic rubber, and natural rubber. Silicone rubber, which has excellent heat resistance and chemical resistance, is preferred.

[0091] (3) Membrane thickness

[0092] The thickness of the waterproof and sound-permeable membrane used in this invention is preferably 10–150 μm, more preferably 15–80 μm. If the membrane is too thick, the sound permeability is reduced, and it cannot be used in small electrical products with large internal space constraints. If it is too thin, the strength is reduced, and it is sometimes easy to break.

[0093] 2. Support layer

[0094] (1) Composition of the support layer

[0095] In addition to its waterproofing function, the support layer also serves to support and fix the waterproof and sound-permeable components to the frame, or improve the operability of the waterproof and sound-permeable components. Furthermore, the support layer can absorb the compressive pressure when installed into the frame, or achieve membrane reinforcement and shape stability.

[0096] The support layer is laminated on at least one side of the waterproof and sound-permeable membrane, and may be laminated on only one side or on both sides. In addition, the support layer is not laminated on the entire surface of the waterproof and sound-permeable membrane, but on a portion thereof.

[0097] Preferably, the support layer is stacked on both sides of the waterproof and sound-permeable membrane. If the support layer is stacked on both sides of the waterproof and sound-permeable membrane, the waterproof and sound-permeable membrane will not directly contact the frame when the waterproof and sound-permeable component is installed in the frame. Therefore, it is less likely to cause defects caused by damage or deformation.

[0098] In order to reduce the stress required to compress the membrane surface of the waterproof and sound-permeable component by 40% in the vertical direction to as low as 1 to 600 kPa, it is effective to use a soft material for at least a portion of the support layer.

[0099] The supporting layer can be a single layer or a multilayer stack, but preferably includes at least a portion (or as a whole) of the supporting layer containing a layer of sheet material with a stress of 600 kPa or less required for 40% compression in the vertical direction, and more preferably a layer containing a layer of sheet material with a stress of 300 kPa or less.

[0100] By combining it with a waterproof and sound-permeable membrane that includes a layer using a sheet with low compressive stress as a support layer and has a low tensile modulus of elasticity and is easily deformable, the increase in sound loss due to compression during installation can be significantly suppressed. It should be noted that the "vertical direction" in the layer constituting the support layer refers to the thickness direction of the layer or the direction perpendicular to the surface of the waterproof and sound-permeable membrane when it is laminated with the membrane.

[0101] When the support layer is a single layer, it is preferably a layer of sheet material that requires a stress of 600 kPa or less to compress 40% in the vertical direction, and more preferably a layer of sheet material that requires a stress of 300 kPa or less to compress 40% in the vertical direction.

[0102] When the support layer is composed of multiple layers, at least one of the layers constituting the support layer is preferably a layer of sheet material that requires a stress of 600 kPa or less to compress 40% in the vertical direction, and more preferably a layer of sheet material that requires a stress of 300 kPa or less to compress 40% in the vertical direction.

[0103] When the support layer is composed of multiple layers, there are no particular restrictions on the layer composition. As a layer of sheet material for which the stress required to compress 40% in the above-mentioned vertical direction is 600 kPa or less (hereinafter referred to as "sheet material with compressive stress of 600 kPa or less"), multiple layers of sheet material using different resin types or having different compressive stresses within the above-mentioned range can be stacked.

[0104] Alternatively, a layer of rigid sheet material (a layer that hardly deforms under compression during use) that requires a stress of more than 600 kPa to compress 40% in the vertical direction can be used as a spacer layer.

[0105] (2) Use sheets with a compressive stress of less than 600 kPa.

[0106] Sheets with compressive stress below 600 kPa are preferably made of synthetic resin materials. Examples of synthetic resins include polyolefin resins, polyurethane resins, polyacrylic resins, and polyester resins.

[0107] Examples of polyolefin resins include polyethylene, polypropylene, and polyvinyl acetate. Examples of polyurethane resins include polyester polyurethane, polyether polyurethane, and polycarbonate polyurethane.

[0108] Examples of polyacrylic resins include polyacrylate and polymethacrylate. Examples of polyester resins include polyethylene terephthalate (PET) and polybutylene terephthalate.

[0109] In addition, examples include polyvinyl chloride, acrylic rubber, and silicone rubber. Preferably, synthetic resins selected from the group consisting of polyolefin resins, polyacrylic resins, and polyurethane resins are used.

[0110] The synthetic resin material can be porous or non-porous, but in order to control the stress required for 40% compression in the vertical direction to below 600 kPa, a sheet material mainly composed of a sheet layer (the layer constituting the sheet) of porous synthetic resin material is preferred. Examples of porous synthetic resin materials include polyolefin porous materials such as polyethylene and polypropylene, polyurethane porous materials, and acrylic resin porous materials.

[0111] The sheet material, which is mainly composed of a sheet layer made of the aforementioned porous synthetic resin material, may consist solely of a sheet layer made of the porous synthetic resin material, or it may be mainly composed of the porous synthetic resin material and include other sheet layers. For example, sheet layers (auxiliary layers) made of materials other than the porous synthetic resin material can be exemplified by non-porous synthetic resin materials such as non-porous polyester resin materials.

[0112] There is no particular limitation on the thickness of the auxiliary layer. It is preferable that the stress required for the sheet as a whole to be compressed by 40% in the vertical direction is less than 600 kPa. Therefore, the thickness of the sheet layer made of porous synthetic resin material is preferably more than 50%, more preferably more than 70%, and particularly preferably more than 80% relative to the thickness of the whole sheet.

[0113] Sheets with compressive stress below 600 kPa may also have an adhesive layer on at least one side. The adhesive layer may be applied to only one side or both sides of the sheet. The adhesive layer can be formed, for example, by applying an adhesive. Examples of adhesives include acrylic adhesives, silicone adhesives, and rubber adhesives.

[0114] There is no particular limitation on the thickness of the adhesive layer. It is preferable that the stress required to compress the sheet as a whole by 40% in the vertical direction is less than 600 kPa. Therefore, the thickness of the sheet layer made of porous synthetic resin material is preferably more than 50% of the thickness of the sheet as a whole, more preferably more than 70%, and particularly preferably more than 80%.

[0115] When both the above-mentioned auxiliary layer and adhesive layer are provided, it is also preferable that the stress required for the sheet as a whole to be compressed by 40% in the vertical direction is 600 kPa or less, and the thickness of the sheet layer made of porous synthetic resin material is preferably 50% or more, more preferably 70% or more, and particularly preferably 80% or more, relative to the thickness of the sheet as a whole.

[0116] As a waterproof adhesive layer using sheet material with a compressive stress of 600 kPa or less, an adhesive waterproof tape formed by applying adhesive to one or both sides of a core material made of porous synthetic resin is preferred. A double-sided adhesive waterproof tape formed by applying adhesive to both sides of a core material made of porous synthetic resin is also preferred. This waterproof adhesive layer provides waterproofing or bonding functions at the interface between the waterproof and sound-permeable membrane and the support layer, at the interface between the sheet material layers within the support layer, and at the interface between the support layer and the frame.

[0117] An adhesive layer may not be required on sheets with compressive stress below 600 kPa. A layer (buffer layer) made of sheet material with compressive stress below 600 kPa without an adhesive layer can be used to compress the buffer layer and utilize its reaction force to fix it to the frame, improving the waterproofness of the boundary between the frame and the waterproof and sound-permeable components. The buffer layer can also be the outermost layer of the support layer.

[0118] There is no particular limitation on the thickness of the sheet material with a compressive stress of 600 kPa or less, but it is preferred to have a thickness of 10 μm or more, more preferably 30 μm or more, further preferably 100 μm or more, and particularly preferably 150 μm or more. There is also no particular limitation on the upper limit of the thickness, but it is preferred to have a thickness of 3000 μm or less, more preferably 1500 μm or less, further preferably 600 μm or less, and particularly preferably 400 μm or less.

[0119] The physical properties of sheets with compressive stress below 600 kPa are not substantially dependent on the type of resin. However, when the sheet with compressive stress below 600 kPa is mainly composed of a sheet layer made of porous polyolefin resin material, the stress required to compress by 40% in the vertical direction is more preferably 50 to 300 kPa, and even more preferably 80 to 250 kPa.

[0120] When the sheet material with a compressive stress of 600 kPa or less is mainly composed of a sheet layer made of a porous polyurethane resin or a porous polyacrylic resin, the stress required for 40% compression in the vertical direction is more preferably 0.1 to 100 kPa, further preferably 0.1 to 30 kPa, and particularly preferably 0.1 to 10 kPa. When forming the support layer, it is preferable to combine layers of various resin types as needed.

[0121] More specifically, sheets with a compressive stress of 600 kPa or less can be exemplified by sheets consisting primarily of a sheet layer made of a porous polyolefin resin material and having adhesive layers on both sides. Alternatively, sheets consisting primarily of a sheet layer made of a porous polyurethane resin material or a porous polyacrylic acid resin material and having a non-porous PET layer as an auxiliary layer can be exemplified.

[0122] (3) Spacer layer

[0123] On a portion of the support layer, a layer using a rigid sheet exhibiting high compressive stress can be provided as a spacer layer. The spacer layer is preferably formed of a non-porous synthetic resin, specifically, examples include non-porous polyethylene terephthalate (PET) and other polyester films.

[0124] The spacer layer is intended to adjust the overall thickness of the waterproof and sound-permeable component and to provide stabilization through structural support (maintaining thickness without deformation when the waterproof and sound-permeable component is compressed during use). The spacer layer may or may not have an adhesive layer. For example, it can be made of adhesive-coated waterproof tape or PET film without adhesive coating on one or both sides.

[0125] The spacer layer is a hard layer that hardly deforms under compression during use. Compressing the thickness by 40% is not easy in itself. At least in the vertical direction, the stress required to compress by 40% is indeed in the range of more than 600 kPa, but it is not necessarily clear. However, it is preferred that the compressive stress is at least 1 MPa or more, more preferably 10 MPa or more, and particularly preferably 100 MPa or more.

[0126] The thickness of each spacer layer is not particularly limited, but is preferably 5 to 200 μm, more preferably 5 to 150 μm. When the support layer contains multiple spacer layers, the total thickness is preferably 10 to 300 μm, more preferably 20 to 250 μm.

[0127] (4) Construction of the support layer

[0128] (i) Layer structure

[0129] The support layer is laminated on at least one side of the waterproof and sound-permeable membrane, serving to fix the waterproof and sound-permeable components to the frame and improve operability. The support layer may be laminated on only one side of the waterproof and sound-permeable membrane or on both sides.

[0130] Preferably, the support layer is stacked on both sides of the waterproof and sound-permeable membrane. If the support layer is stacked on both sides of the waterproof and sound-permeable membrane, the waterproof and sound-permeable membrane will not directly contact the frame when the waterproof and sound-permeable components are assembled into the frame, thus reducing the likelihood of defects caused by damage or deformation.

[0131] When the waterproof and sound-permeable membrane has a support layer on only one side, the support layer can be a single layer or multiple layers.

[0132] When a waterproof and sound-permeable membrane has support layers on both sides, it is possible to make one side a single layer and the other side a single layer. In this case, the two can be the same layer or different layers made of different kinds of materials.

[0133] When a waterproof and sound-permeable membrane has support layers on both sides, one side can be made into a single layer and the other side into multiple layers. Alternatively, the support layers on both sides can also be made into multiple layers.

[0134] When the support layer is a single layer, it is preferably composed of a layer of sheet material with a compressive stress of 600 kPa or less, laminated on the waterproof and sound-permeable membrane. When the support layer is multi-layered, it is preferable that at least one layer is a layer of sheet material with a compressive stress of 600 kPa or less. This improves the waterproofness of the boundary between the waterproof and sound-permeable membrane and the support layer.

[0135] Using a layer of sheet material made of soft material with a compressive stress of less than 600 kPa can suppress 40% of the overall compressive stress of the waterproof and sound-permeable component, reduce the force applied to the waterproof and sound-permeable membrane when it is installed in the frame with a high compression ratio, and reduce sound loss.

[0136] When the support layer is multi-layered, as described above, it is preferable that at least one layer is a sheet material with a compressive stress of 600 kPa or less. As a layer using a sheet material with a compressive stress of 600 kPa or less, it is preferable to use a sheet material comprising a sheet layer mainly composed of the above-described porous synthetic resin material.

[0137] More specifically, as a sheet material with a compressive stress of 600 kPa or less, for example, a sheet material mainly composed of a porous polyolefin resin material and preferably having a compressive stress of about 50 to 300 kPa can be used; or a sheet material mainly composed of a porous polyurethane resin material or a porous polyacrylic acid resin material and preferably having a compressive stress of about 0.1 to 100 kPa can be used. Alternatively, a waterproof adhesive layer with an adhesive layer and / or a buffer layer without an adhesive layer can be used.

[0138] It is possible to combine these layers with adhesive layers, layers without adhesive layers, or various layers with different compressive stresses, or further, appropriately use spacer layers, to design a support layer with the desired compressive stress and thickness. Moreover, by combining these with a suitable waterproof and sound-permeable membrane, it is possible to obtain a waterproof and sound-permeable component with a stress of 1 kPa to 600 kPa required for 40% compression in a direction perpendicular to the membrane surface.

[0139] Furthermore, the waterproof and sound-permeable component of the present invention can be manufactured by forming sheets, films, membranes, etc., constituting each layer into a suitable and desired shape and then laminating them based on the above design. As a lamination method, methods known such as pressing to bond the layers can be cited as examples.

[0140] As a multi-layered structure, it contains one or more waterproof adhesive layers or buffer layers, and can be combined with one or two or more spacer layers as needed. In addition, two or more different types of waterproof adhesive layers, or two or more different types of buffer layers, or a combination of waterproof adhesive layers and buffer layers can be stacked, and further, one or two or more spacer layers can be combined as needed.

[0141] In addition, preferably at least one of the layers constituting the support layer is a waterproof adhesive layer.

[0142] More specifically, a support layer (preferably a waterproof adhesive layer or a buffer layer) comprising layers of sheets (of the same or different types) with a compressive stress of less than 600 kPa is laminated on one or both sides of the waterproof and sound-permeable membrane. In the support layer, a spacer layer (preferably an adhesive waterproof tape or a non-porous synthetic resin film such as a non-porous PET film with a core material made of non-porous synthetic resin) may also be appropriately laminated as needed.

[0143] If a spacer layer is formed between the waterproof and sound-permeable membrane and the sheet material layer containing the supporting layer with a compressive stress of 600 kPa or less, the overall layer structure of the waterproof and sound-permeable component is stabilized. Alternatively, a shape can be formed in which spacer layers are provided on both sides of the sheet material layer containing the supporting layer with a compressive stress of 600 kPa or less, thereby further stabilizing the overall layer structure of the waterproof and sound-permeable component.

[0144] Regarding the structure of the waterproof and sound-permeable membrane and the support layer, preferred specific examples are shown below, but are not limited thereto.

[0145] • A waterproof adhesive layer is applied to one side of the waterproof and sound-permeable membrane, and the same or different waterproof adhesive layers are applied to the opposite side.

[0146] • A waterproof adhesive layer or spacer layer is provided on one side of the waterproof and sound-permeable membrane, and a buffer layer is provided on the opposite side.

[0147] • A waterproof adhesive layer or spacer layer is disposed on one side of the waterproof and sound-permeable membrane, and a spacer layer is disposed on the opposite side of the membrane in contact with the waterproof and sound-permeable membrane, and a waterproof adhesive layer or buffer layer is further stacked.

[0148] • A waterproof adhesive layer or spacer layer is disposed on one side of the waterproof and sound-permeable membrane, and a spacer layer is disposed on the opposite side of the membrane in contact with the waterproof and sound-permeable membrane. A waterproof adhesive layer or buffer layer is then stacked on top of the spacer layer, and a further spacer layer is stacked on top of that.

[0149] There is no particular limitation on the thickness of the support layer (the thickness of the single layer or the total thickness of the constituent layers when composed of multiple layers), preferably 30 to 3000 μm, more preferably 100 to 1500 μm, further preferably 300 to 1000 μm, and particularly preferably 500 to 800 μm.

[0150] The thickness of the layer of sheet material with a compressive stress of less than 600 kPa is the same as that of the single layer, preferably 30 to 3000 μm, and more preferably 100 to 1500 μm.

[0151] The total thickness of the layers constituting the support layer that use sheets with a compressive stress of 600 kPa or less preferably accounts for 30% or more, more preferably 40% or more, and particularly preferably 50% or more of the total thickness of the waterproof and sound-permeable component.

[0152] When layers of sheet material with a compressive stress of 600 kPa or less are applied to both sides of the waterproof and sound-permeable membrane, it is desirable that the total thickness of the layers of sheet material with a compressive stress of 600 kPa or less is preferably 60% or more, more preferably 70 to 98%, further preferably 85 to 98%, and particularly preferably 90 to 96% of the total thickness of the waterproof and sound-permeable component.

[0153] When the layer of sheet material with compressive stress of 600 kPa or less is provided only on one side of the waterproof and sound-permeable membrane, it is desirable that the total thickness of the layer of sheet material with compressive stress of 600 kPa or less is preferably 40% or more, more preferably 50% or more, further preferably 50 to 70%, and particularly preferably 50 to 60% of the total thickness of the waterproof and sound-permeable component.

[0154] Here, the thickness of the waterproof and sound-permeable component refers to the thickness of the thickest part of the waterproof and sound-permeable component, which includes the waterproof and sound-permeable membrane and the support layer.

[0155] (ii) Shape of the support layer

[0156] When a support layer is stacked on both sides of a waterproof and sound-permeable membrane, it is preferable that the support layers on both sides are located at positions where they overlap in the same shape when viewed from the vertical direction of the waterproof and sound-permeable membrane surface. In this case, the force applied by compression is difficult to be transmitted to the waterproof and sound-permeable membrane.

[0157] When the support layer is stacked on the periphery of the waterproof and sound-permeable membrane, it does not impede the vibration of the membrane, which is therefore preferred. Furthermore, when the support layer has a constant cross-sectional shape in the horizontal direction (parallel to the membrane surface) relative to the membrane surface, the compressive force is difficult to transmit to the membrane, which is also preferred.

[0158] To prevent the stress applied by the compression of the waterproof and sound-permeable component from being biased and to reduce the deformation of the sound-permeable area of ​​the waterproof and sound-permeable membrane, thereby reducing sound loss, it is preferable that the area of ​​the support layer (the cross-section parallel to the membrane surface) stacked on the waterproof and sound-permeable membrane is 1 mm². 2 The above, and more preferably 5mm 2 above.

[0159] On the other hand, in order to facilitate the miniaturization of electrical products through space saving, and to reduce the load on the frame by reducing the force required for compression, the area of ​​the support layer laminated on the waterproof and sound-permeable membrane is preferably 50 mm². 2 The following is a preferred size: 30mm 2 the following.

[0160] 3. Sound-permeable area

[0161] In a waterproof and sound-permeable component consisting of a waterproof and sound-permeable membrane and a support layer stacked on its periphery, sound passes through the part of the waterproof and sound-permeable membrane exposed where the support layer is not stacked, i.e., the sound-permeable area of ​​the waterproof and sound-permeable membrane.

[0162] Since a wider sound-transmitting area results in less sound loss, the preferred area for the sound-transmitting area is 0.5 mm. 2 The above, preferably 1.5mm 2 That's all. On the other hand, since a smaller area results in a more stable shape, is less prone to deformation, and has less sound loss during compression, the area of ​​the sound-transmitting region is preferably 40mm². 2 The following is more preferably 20mm 2 the following.

[0163] For the planar shape of the sound-transmitting area, a circular or near-circular shape is stable and difficult to deform. Therefore, the roundness calculated by mathematical formula (1) is preferably 0.45 to 1, more preferably 0.6 to 1. In addition, it is preferable that it does not have corners.

[0164] (Mathematical Formula 1)

[0165] Roundness = 4 × pi × area ÷ [circumference] 2 ...Mathematical formula (1)

[0166] Figure 2 This illustrates an example of the structure of the waterproof and sound-permeable component of the present invention. The waterproof and sound-permeable component 1 of the present invention is preferably circular, and a support layer 3 is laminated on one or both sides of the waterproof and sound-permeable membrane 2 in such a way as to form around the periphery of the sound-permeable area 4.

[0167] Example

[0168] The present invention will now be described in more detail through examples, but the present invention is not limited to the following examples. Furthermore, the measurement and evaluation of the physical properties in the following examples and comparative examples were performed according to the following methods.

[0169] (1) Sound loss

[0170] use Figure 3 The sound loss measurement is explained. Inside the anechoic chamber 16, a sound with a sound pressure level of 94 dB at a frequency of 1 kHz is emitted from the speaker 11 as a TSP signal. The output of the MEMS (ADMP401) analog microphone 12 built into the microphone tool 13 is converted into digital by an analyzer and analyzed using analysis software (Audiomatica CL IO Pocket). The sound pressure level at a frequency of 1 kHz is measured.

[0171] The microphone tool 13 is a metallic box shape with an opening 14 on its outer surface for sound to enter, a waterproof and sound-permeable component mounting part with a specified gap, and an internal space 15 sealed by installing the waterproof and sound-permeable component 1. A MEMS analog microphone 12 is arranged in the internal space 15.

[0172] The speaker 11, opening 14, waterproof and sound-transparent component 1, and MEMS analog microphone 12 are arranged in a straight line without being obstructed by the structure of the microphone tool 13. The opening 14 is a circle with a diameter of 1 mm, the distance from the waterproof and sound-transparent component 1 in the internal space 15 to the MEMS analog microphone 12 is 6 mm, and the volume of the internal space is 27 mm². 3 .

[0173] The microphone tool 13 is positioned 4.5 cm away from the speaker 11 with the plane having the opening 14 parallel to the sound-emitting part of the speaker (so that the sound is incident perpendicularly).

[0174] The sound pressure level measured using only a microphone tool and the sound pressure level measured with a waterproof and sound-permeable component attached to the opening of the microphone tool are used to calculate the acoustic loss. The lower the acoustic loss, the higher the sound transmission.

[0175] By appropriately adjusting the gap of the installation part of the waterproof and sound-permeable component, the acoustic loss at 0% compression and 40% compression were measured. The acoustic loss at 0% compression was subtracted from the acoustic loss at 40% compression to calculate ΔdBV. A smaller ΔdBV value indicates better suppression of the increase in acoustic loss caused by compression. Measurements were performed on 10 samples, and the mean and standard deviation were calculated.

[0176] (2) Tensile test

[0177] Test pieces measuring 50 mm wide and 80 mm long were mounted on a tensile testing machine (trade name "Autograph AG-IS type", manufactured by Shimadzu Corporation) with a clamping interval of 50 mm and subjected to tensile testing at a tensile speed of 150 mm / min. The measurement temperature was 22°C and the measurement humidity was 65%. The initial slope of the obtained stress-deformation curve was divided by the cross-sectional area (mm²) of the waterproof and sound-permeable membrane. 2 The tensile modulus of elasticity (MPa) was calculated. The test piece was rotated 90° longitudinally and 90° laterally, and the above measurements were performed 5 times each, for a total of 10 measurements, and the average value was calculated.

[0178] (3) Water pressure resistance

[0179] Measurements were performed according to JIS L 1092B method (high water pressure method). However, due to insufficient measurement area of ​​the waterproof and sound-permeable component, measurements were taken by attaching the component to an SUS board with circular holes, and leakage was determined at a single point. To prevent membrane deformation and subsequent breakage during the measurement of the waterproof and sound-permeable membrane, measurements were performed by overlapping a plain-weave fabric (which is less likely to affect the water pressure resistance of the porous membrane) on the opposite side of the surface to which water pressure was applied. The plain-weave fabric was woven with 6-nylon multifilament yarn (80 dtex / 24 filament) for the warp and 6-nylon multifilament yarn (80 dtex / 34 filament) for the weft, with a warp density of 120 ends / 2.54 cm and a weft density of 90 ends / 2.54 cm.

[0180] (4) Thickness

[0181] The thickness of the waterproof and sound-permeable component was measured by taking vertical cross-sectional photographs at 300 to 5000x magnification using a scanning electron microscope (Hitachi High Technology S-3000N, Ltd.).

[0182] (5) Compressive stress

[0183] Using a compression testing machine (KES-G5 manufactured by KatoTech Co., Ltd.), such as Figure 4 In the illustrated embodiment, the waterproof and sound-permeable component 1 is used by moving the parallel plate 17 in the compression direction 18 (a direction perpendicular to the membrane surface of the waterproof and sound-permeable membrane) and applying a load. The stress is calculated by measuring the force required to compress 40% of the maximum thickness of the waterproof and sound-permeable component (the sum of the thicknesses of the support layer and the waterproof and sound-permeable membrane), dividing it by the area of ​​the support layer (the area overlapping in the vertical direction). A 2cm measuring unit is used. 2 The circular fitting was compressed at a rate of 0.01 mm / min. Measurements were performed on five samples, and the average value was calculated.

[0184] The cushioning material, double-sided adhesive waterproof tape, and non-porous PET film used in the support layer were each pre-cut into 2.5mm × 2.5mm = 6.25mm pieces. 2 The compressive stress of each sample was measured. Each measurement was performed on five samples, and the average value was calculated.

[0185] Furthermore, because samples made of non-porous PET or with a core material consisting solely of non-porous PET are difficult to compress to 40%, it is challenging to obtain a sample size of 6.25 mm. 2 The upper limit for measurement is values ​​above 1569 kPa.

[0186] [Example]

[0187] A polyurethane resin solution with the following formulation was prepared.

[0188] <Prescription>

[0189] MP865 PS; 100 parts by weight

[0190] (Manufactured by DIC, polyurethane resin, solids content 30% by mass, 100% modulus 11 MPa)

[0191] LEATHEROID LU2850M; 65 parts by weight

[0192] (Manufactured by Daihatsu Seika Co., Ltd., silica microparticle dispersion, solid content 20% by mass)

[0193] Shellac Black L1584; 4 parts by weight

[0194] (Manufactured by DIC Corporation, black pigment, solid content 25% by mass)

[0195] N,N-dimethylformamide; 28 parts by weight

[0196] Next, using a roller coater, the aforementioned polyurethane resin solution was applied to a release substrate to achieve a coating thickness of 30 μm for the resulting waterproof and sound-permeable membrane. Then, it was immersed in water at 20°C for 1.5 minutes to allow complete solidification. Following this, it was washed in warm water at 50°C for 5 minutes, and then heat-treated at 130°C for 2 minutes to dry. The release substrate was then removed to obtain the waterproof and sound-permeable membrane. The tensile modulus of elasticity of the waterproof and sound-permeable membrane was measured to be 3.9 MPa, its water pressure resistance was 70 kPa, and its air permeability was 19 seconds / 100 mL.

[0197] The waterproof and sound-permeable membrane is punched into a rectangle with a long side length of 4.4 mm and a short side length of 3.4 mm using a Thomson die. The support layer is also punched into a rectangle with a long side length of 4.4 mm and a short side length of 3.4 mm, with an elliptical opening at the center having a major axis diameter of 2.4 mm and a minor axis diameter of 1.4 mm.

[0198] The support layer uses double-sided adhesive waterproof tape 1 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5225VSB"; porous polyethylene; thickness 250μm) and double-sided adhesive waterproof tape 2 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5240VSB"; porous polyethylene; thickness 400μm).

[0199] A waterproof and sound-permeable component was fabricated by layering and pressing together double-sided adhesive waterproof tape 1, a waterproof and sound-permeable membrane, and then double-sided adhesive waterproof tape 2. The thickness of the waterproof and sound-permeable component is 680 μm. The area of ​​the sound-permeable region is 2.64 mm². 2 The roundness is 0.9, and the area of ​​the support layer is 12.3 mm². 2 .

[0200] The stress required to compress 40% of the double-sided adhesive waterproof tape 1 is 111 kPa, and the stress required to compress 40% of the double-sided adhesive waterproof tape 2 is 175 kPa. Double-sided adhesive waterproof tape 1 accounts for 36.8% of the total thickness of the waterproof and sound-permeable component, and double-sided adhesive waterproof tape 2 accounts for 58.8% of the total thickness of the waterproof and sound-permeable component, totaling 95.6%.

[0201] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0202] By manufacturing waterproof and sound-permeable components that require minimal stress to compress by 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity and compressed by 40%.

[0203] [Example 2]

[0204] Except for the support layer, which consists of two layers of double-sided adhesive waterproof tape 1 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5225VSB"; thickness 250μm) and double-sided adhesive waterproof tape 3 (manufactured by Nitto Denko Co., Ltd., trade name "No.5601"; non-porous PET; thickness 10μm), and cushioning material 1 (manufactured by INOAC CORPORATION Co., Ltd., trade name "PORON SR-S15P"; porous polyurethane resin + PET; thickness 500μm), a waterproof and sound-permeable component was fabricated in the same order as in Example 1, except that the waterproof and sound-permeable component was laminated in the same order as in Example 1. The thickness of the waterproof and sound-permeable component is 800μm.

[0205] The stress required to compress 40% of the double-sided adhesive waterproof tape 1 is 111 kPa, and the stress required to compress 40% of the cushioning material 1 is 0.2 kPa. Furthermore, since the core material of the double-sided adhesive waterproof tape 3 is non-porous PET, compressing it to 40% is inherently difficult. Therefore, it is clear that the stress required to compress 40% of the double-sided adhesive waterproof tape 3 is at least 6.25 mm in diameter. 2 The upper limit for measurement is above 1569 kPa.

[0206] The double-sided adhesive waterproof tape 1 accounts for 31.2% of the total thickness of the waterproof and sound-permeable component, and the cushioning material 1 accounts for 62.5% of the total thickness of the waterproof and sound-permeable component, totaling 93.7%.

[0207] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0208] By manufacturing waterproof and sound-permeable components that require minimal stress to compress by 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity and compressed by 40%.

[0209] [Example 3]

[0210] Except for the support layer, which uses two layers of double-sided adhesive waterproof tape 1 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5225VSB", thickness 250μm), double-sided adhesive waterproof tape 3 (manufactured by Nitto Denko Co., Ltd., trade name "No.5601"; thickness 10μm), and cushioning material 2 (manufactured by INOAC CORPORATION Co., Ltd., trade name "PORON SR-S40P"; porous polyurethane resin + PET; thickness 400μm), a waterproof and sound-permeable component was manufactured in the same order as in Example 1, except that the support layer used two layers of double-sided adhesive waterproof tape 1 (manufactured by Sekisui Chemicals Co., Ltd., trade name "PORON SR-S40P"; porous polyurethane resin + PET; thickness 400μm). The thickness of the waterproof and sound-permeable component was 700μm.

[0211] The stress required to compress 40% of the double-sided adhesive waterproof tape 1 is 111 kPa, and the stress required to compress 40% of the cushioning material 2 is 1 kPa. The stress required to compress 40% of the double-sided adhesive waterproof tape 3 is over 1569 kPa. The double-sided adhesive waterproof tape 1 accounts for 35.7% of the total thickness of the waterproof and sound-permeable component, and the cushioning material 2 accounts for 57.1% of the total thickness of the waterproof and sound-permeable component, totaling 92.8%.

[0212] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0213] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0214] [Example 4]

[0215] Except for the support layer, which consists of two layers of double-sided adhesive waterproof tape 1 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5225VSB"; thickness 250μm), double-sided adhesive waterproof tape 3 (manufactured by Nitto Denko Co., Ltd., trade name "No.5601"; thickness 10μm), and cushioning material 3 (manufactured by Iwatani Sangyo Co., Ltd., trade name "ISR-ACF-TH"; porous acrylic resin; thickness 400μm), a waterproof and sound-permeable component was fabricated in the same order as in Example 1, except that the waterproof and sound-permeable component was 700μm thick.

[0216] The stress required to compress 40% of the double-sided adhesive waterproof tape 1 is 111 kPa, and the stress required to compress 40% of the cushioning material 3 is 2 kPa. The stress required to compress 40% of the double-sided adhesive waterproof tape 3 is over 1569 kPa. The double-sided adhesive waterproof tape 1 accounts for 35.7% of the total thickness of the waterproof and sound-permeable component, and the cushioning material 3 accounts for 57.1% of the total thickness of the waterproof and sound-permeable component, totaling 92.8%.

[0217] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0218] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0219] [Example 5]

[0220] A waterproof and sound-permeable membrane was made into a circle with a diameter of 4 mm, and a support layer was also made into a circle with a diameter of 4 mm, having a circular opening with a diameter of 2.2 mm at its center. The support layer consisted of two layers of double-sided adhesive waterproof tape 4 (manufactured by Nitto Denko Corporation, trade name "No. 5615"; non-porous PET; thickness 150 μm), two layers of double-sided adhesive waterproof tape 5 (manufactured by Nitto Denko Corporation, trade name "No. 5605"; non-porous PET; thickness 50 μm), two layers of cushioning material 2 (manufactured by INOAC CORPORATION, trade name "PORON SR-S40P"; porous polyurethane resin + PET; thickness 400 μm), and a 50 μm thick PET film. These layers were stacked in the following order: double-sided adhesive waterproof tape 4, waterproof and sound-permeable membrane, double-sided adhesive waterproof tape 5, PET film, double-sided adhesive waterproof tape 5, and cushioning material 2. Otherwise, a waterproof and sound-permeable component was manufactured in the same manner as in Example 1. The thickness of the waterproof and sound-permeable component was 730 μm. The area of ​​the sound-transmitting region is 3.8mm. 2 The roundness is 1, and the area of ​​the support layer is 8.8 mm². 2 .

[0221] The stress required for 40% compression of the cushioning material 2 is 1 kPa. The stress required for 40% compression of the double-sided adhesive waterproof tape 4, double-sided adhesive waterproof tape 5, and 50 μm thick PET film is over 1569 kPa. The cushioning material 2 accounts for 54.8% of the total thickness of the waterproof and sound-permeable component.

[0222] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0223] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0224] [Example 6]

[0225] Except that the supporting layer is a circle with a diameter of 6 mm and a circular opening with a diameter of 2.2 mm at its center, the waterproof and sound-permeable component was manufactured in the same manner as in Example 5. The thickness of the waterproof and sound-permeable component is 730 μm. The area of ​​the sound-permeable region is 3.8 mm². 2 The roundness is 1, and the area of ​​the support layer is 24.5 mm². 2 .

[0226] The stress required to compress 40% of the cushioning material 2 is 1 kPa. Cushioning material 2 accounts for 54.8% of the total thickness of the waterproof and sound-permeable component.

[0227] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0228] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0229] [Example 7]

[0230] The waterproof and sound-permeable component was fabricated using two layers of double-sided adhesive waterproof tape 4 (manufactured by Nitto Denko Corporation, trade name "No. 5615"; thickness 150μm), double-sided adhesive waterproof tape 5 (manufactured by Nitto Denko Corporation, trade name "No. 5605"; thickness 50μm), cushioning material 4 (manufactured by INOAC CORPORATION, trade name "PORON SR-S20P"; porous polyurethane + PET; thickness 400μm), and a 50μm thick PET film. The layers were stacked sequentially as in Example 5. The thickness of the waterproof and sound-permeable component was 730μm.

[0231] The stress required for 40% compression of the buffer component 4 is 0.2 kPa. The buffer material 4 accounts for 54.8% of the total thickness of the waterproof and sound-permeable component.

[0232] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0233] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0234] [Example 8]

[0235] Except that the supporting layer is circular with a diameter of 6 mm and has a circular opening with a diameter of 2.2 mm at its center, the waterproof and sound-permeable component was manufactured in the same manner as in Example 7. The thickness of the waterproof and sound-permeable component is 730 μm. The area of ​​the sound-permeable region is 3.8 mm². 2 The roundness is 1, and the area of ​​the support layer is 24.5 mm². 2 .

[0236] The stress required for 40% compression of the buffer component 4 is 0.2 kPa. The buffer material 4 accounts for 54.8% of the total thickness of the waterproof and sound-permeable component.

[0237] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0238] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0239] [Example 9]

[0240] Except that the support layer uses double-sided adhesive waterproof tape 1 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5225VSB"; thickness 250μm) and double-sided adhesive waterproof tape 6 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5230VSB"; porous polyethylene; thickness 300μm), and the double-sided adhesive waterproof tape 1, waterproof and sound-permeable membrane, and double-sided adhesive waterproof tape 6 are layered sequentially, the waterproof and sound-permeable component was manufactured in the same manner as in Example 1. The thickness of the waterproof and sound-permeable component is 580μm.

[0241] The stress required to compress 40% of the double-sided adhesive waterproof tape 6 is 234 kPa. The stress required to compress 40% of the double-sided adhesive waterproof tape 1 is 111 kPa. The double-sided adhesive waterproof tape 6 accounts for 51.7% of the total thickness of the waterproof and sound-permeable component, and the double-sided adhesive waterproof tape 1 accounts for 43.1% of the total thickness of the waterproof and sound-permeable component, together accounting for 94.8%.

[0242] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0243] By manufacturing waterproof and sound-permeable components that require minimal stress to compress to 40%, sound loss is unlikely to increase even when using waterproof and sound-permeable membranes with low tensile modulus of elasticity for 40% compression.

[0244] [Comparative Example 1]

[0245] Except that the support layer uses double-sided adhesive waterproof tape 7 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5230SKB"; porous polyethylene; thickness 300μm) and double-sided adhesive waterproof tape 8 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5225SKB"; porous polyethylene; thickness 250μm), and the double-sided adhesive waterproof tape 7, waterproof and sound-permeable membrane, and double-sided adhesive waterproof tape 8 are layered sequentially, the waterproof and sound-permeable component was manufactured in the same manner as in Example 1. The stress required to compress the double-sided adhesive waterproof tape 7 by 40% is 780 kPa. The stress required to compress the double-sided adhesive waterproof tape 8 by 40% is 682 kPa. The thickness of the waterproof and sound-permeable component is 580 μm.

[0246] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0247] Because the stress required for 40% compression is large, the sound loss increases when using a waterproof and sound-permeable membrane with a low tensile modulus of elasticity under 40% compression, making it unsuitable for use under compression.

[0248] [Comparative Example 2]

[0249] Except for the support layer, which uses two layers of double-sided adhesive waterproof tape 7 (manufactured by Sekisui Chemicals Co., Ltd., trade name "5230SKB"; porous polyethylene; thickness 300μm), and the layers of double-sided adhesive waterproof tape 7, waterproof and sound-permeable membrane, and double-sided adhesive waterproof tape 7 are stacked sequentially, the waterproof and sound-permeable component was manufactured in the same manner as in Example 1. The stress required for 40% compression of the double-sided adhesive waterproof tape 7 is 780kPa. The thickness of the waterproof and sound-permeable component is 630μm.

[0250] The sound loss, water pressure resistance, and stress required for 40% compression of the waterproof and sound-permeable components are shown in Table 1.

[0251] Because the stress required for 40% compression is large, the sound loss increases when using a waterproof and sound-permeable membrane with a low tensile modulus of elasticity under 40% compression, making it unsuitable for use under compression.

[0252] In addition, the details of the materials used in the above embodiments and comparative examples are as follows.

[0253] • Double-sided adhesive waterproof tape 1; manufactured by Sekisui Chemicals Co., Ltd., trade name "5225VSB" (porous polyethylene: 250μm thick)

[0254] • Double-sided adhesive waterproof tape 2; manufactured by Sekisui Chemicals Co., Ltd., trade name "5240VSB" (porous polyethylene: 400μm thick)

[0255] • Double-sided adhesive waterproof tape 3; manufactured by Nitto Denko Co., Ltd., trade name "No. 5601" (non-porous PET film: 10μm thick)

[0256] • Double-sided adhesive waterproof tape 4; manufactured by Nitto Denko Co., Ltd., trade name "No. 5615" (non-porous PET film: 150μm thick)

[0257] • Double-sided adhesive waterproof tape 5; manufactured by Nitto Denko Co., Ltd., trade name "No. 5605" (non-porous PET film: 50μm thick)

[0258] • Double-sided adhesive waterproof tape 6; manufactured by Sekisui Chemicals Co., Ltd., trade name "5230VSB" (porous polyethylene: 300μm thick)

[0259] • Double-sided adhesive waterproof tape 7; manufactured by Sekisui Chemicals Co., Ltd., trade name "5230SKB" (porous polyethylene: 300μm thick)

[0260] • Double-sided adhesive waterproof tape 8; manufactured by Sekisui Chemicals Co., Ltd., trade name "5225SKB" (porous polyethylene: 250μm thick)

[0261] • Cushioning material 1; Manufactured by INOAC CORPORATION, trade name "PORON SR-S15P" (450μm porous polyurethane resin + 50μm non-porous PET: total thickness 500μm)

[0262] • Cushioning material 2; Manufactured by INOAC CORPORATION, trade name "PORON SR-S40P" (350μm porous polyurethane resin + 50μm non-porous PET: total thickness 400μm)

[0263] • Cushioning material 3; manufactured by Iwatani Sangyo Co., Ltd., trade name "ISR-ACF-TH" (porous acrylic resin; thickness 400μm)

[0264] • Cushioning material 4; Manufactured by INOAC CORPORATION, trade name "PORON SR-S20P" (350μm porous polyurethane resin + 50μm non-porous PET: total thickness 400μm)

[0265] In addition, the double-sided adhesive waterproof tapes 1, 2, and 6, and the cushioning materials 1, 2, 3, and 4 correspond to the "sheet material for which the stress required to compress 40% in the vertical direction is less than 600 kPa" of the present invention. The double-sided adhesive waterproof tapes 3, 4, and 5 correspond to the spacer layer.

[0266] [Table 1]

[0267]

[0268] Industrial utilization potential

[0269] The waterproof and sound-permeable component of this invention has high waterproof performance and, even when compressed to prevent sound interference within the enclosure, exhibits low acoustic loss and does not impair the acoustic characteristics of the microphone and speaker. Therefore, the waterproof and sound-permeable component of this invention is suitable for waterproof protection of microphones and speakers in electrical products.

[0270] Explanation of reference numerals in the attached figures

[0271] 1: Waterproof and soundproof components

[0272] 2: Waterproof sound-permeable membrane

[0273] 3: Support layer

[0274] 4: Sound-permeable area

[0275] 11: Speaker

[0276] 12: MEMS analog microphone

[0277] 13: Microphone tools

[0278] 14: Opening

[0279] 15: Interior Space

[0280] 16: Silencer

[0281] 17: Parallel plate

[0282] 18: Compression direction

Claims

1. A waterproof and sound-permeable component, wherein a support layer is laminated on at least one side of a waterproof and sound-permeable membrane, characterized in that, The waterproof and sound-permeable membrane has sound-permeable areas exposed on both sides. The stress required to compress the membrane by 40% in a direction perpendicular to the membrane surface is 1 kPa to 600 kPa, and the waterproof and sound-permeable membrane is a porous membrane.

2. The waterproof and sound-permeable component according to claim 1, characterized in that, The support layer consists of a single layer or multiple layers, and includes at least a layer of sheet material that requires a stress of less than 600 kPa to compress 40% in the vertical direction.

3. The waterproof and sound-permeable component according to claim 2, characterized in that, Sheets requiring a stress of less than 600 kPa to compress 40% in the vertical direction comprise sheet layers made of porous synthetic resin material.

4. The waterproof and sound-permeable component according to claim 3, characterized in that, The synthetic resin porous material is a porous material of synthetic resin selected from the group consisting of polyolefin resins, polyurethane resins and acrylic resins.

5. The waterproof and sound-permeable component according to any one of claims 2 to 4, characterized in that, The layers constituting the support layer that use sheet material with a stress of less than 600 kPa required to compress 40% in the vertical direction account for more than 40% of the overall thickness of the waterproof and sound-permeable component.

6. The waterproof and sound-permeable component according to claim 1, characterized in that, The tensile elastic modulus of the waterproof and sound-permeable membrane is 0.5MPa ~ 20MPa.

7. The waterproof and sound-permeable component according to claim 1, characterized in that, The waterproof and sound-permeable membrane contains 100% material with a modulus of 1MPa to 20MPa.

8. The waterproof and sound-permeable component according to claim 1, characterized in that, The air permeability of the waterproof and sound-permeable membrane is 3 seconds / 100mL to 500 seconds / 100mL according to the JIS L 1096 Göller method.

9. The waterproof and sound-permeable component according to claim 1, characterized in that, The thickness of the waterproof and sound-permeable membrane is 15μm to 80μm.

10. The waterproof and sound-permeable component according to claim 1, characterized in that, The waterproof and sound-permeable membrane is made of polyurethane resin.

11. The waterproof and sound-permeable component according to claim 1, characterized in that, The area of ​​the support layer on at least one side of the waterproof and sound-permeable membrane is 1 mm². 2 ~50mm 2 .

12. The waterproof and sound-permeable component according to claim 1, characterized in that, The sound-transmitting area satisfies at least one of the following conditions a) and b): a) The planar shape has no angles and a roundness of 0.45~1; b) Area is 0.5 mm 2 ~40mm 2 .

13. The waterproof and sound-permeable component according to claim 1, characterized in that, The support layer satisfies at least one of the following conditions c) and d): c) Layered on both sides of the waterproof and sound-permeable membrane; d) Layered around the periphery of the waterproof and sound-permeable membrane.

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