JP6758796B2 - Waterproof sound absorbing member - Google Patents

Description

The present invention relates to a waterproof sound-transmitting member using a waterproof sound-transmitting membrane.

In electronic devices such as mobile phones, laptop computers, smartphones, portable audio devices, and portable game devices, an acoustic device is housed in a housing. These housings have openings to allow the passage of sound. In order to prevent water from entering the housing, a waterproof sound-transmitting film that allows the passage of sound while blocking the passage of water is attached to this opening. In Patent Documents 1 and 2, a polytetrafluoroethylene (PTFE) porous membrane is mentioned as a waterproof sound-transmitting membrane. Patent Document 2 describes a waterproof sound-transmitting film and a support layer having a frame portion that is adhered to the waterproof sound-transmitting film and surrounds an opening whose inner peripheral end is rectangular when viewed along the direction in which sound passes. A waterproof sound-transmitting member provided with, is disclosed.

Japanese Unexamined Patent Publication No. 2008-245332 Japanese Unexamined Patent Publication No. 2012-253481

According to the study by the present inventors, sound distortion is often confirmed in the sound transmission test in the waterproof sound-transmitting member having a support layer having an opening having an elongated rectangular inner peripheral end. Here, the sound distortion is the alteration of the sound that occurs when the waterproof sound-permeable film is attached to the opening of the housing as compared with the case where the waterproof sound-transmitting film is not attached to the opening of the housing. is there. For example, the distortion of sound is perceived by the human ear as a chattering sound (vibration sound that makes the shoji paper tremble). When sound passes through the waterproof sound-transmitting membrane, high-order harmonics, which are high-order frequency components that are integral multiples of the input fundamental wave (sine wave), are generated. Sound distortion is quantified by harmonic distortion represented by the sum of the sounds of higher harmonics, which are distortion components. Increasing sound distortion is a major problem for electronic devices, and especially in high-quality electronic devices, it is required to accurately reproduce sound without distortion.

An object of the present invention is to provide a waterproof sound-transmitting member suitable for reducing distortion of passing sound.

The present invention
Waterproof sound-permeable membrane and
With a support layer adhered to the waterproof sound-transmitting membrane,
The support layer has a frame portion surrounding the internal region and at least one connecting portion connected to the frame portion so as to divide the internal region into two or more openings.
When the rectangle having the smallest area among the virtual rectangles in contact with the internal area so as to include the internal area is the first rectangle, the ratio R1 of the long side to the short side of the first rectangle is 5 or more. Yes,
For each of the two or more openings, when the rectangle having the smallest area among the virtual rectangles in contact with the openings so as to include the openings is the second rectangle, the short side of the second rectangle is used. Provided is a waterproof sound-transmitting member in which at least one connecting portion is arranged so that the ratio R2 of the long side with respect to the ratio R2 is 1 or more and smaller than the ratio R1.

According to the present invention, it is possible to provide a waterproof sound transmitting member in which distortion of passing sound is reduced.

It is a top view which shows typically an example of the waterproof sound-transmitting member of this invention. It is sectional drawing which shows typically an example of the waterproof sound-transmitting member of this invention. It is sectional drawing which shows typically an example of the waterproof sound-transmitting member which concerns on the modification of this invention. It is sectional drawing which shows typically an example of the waterproof sound-transmitting member which concerns on another modification of this invention. It is sectional drawing which shows typically an example of the waterproof sound-transmitting member which concerns on another modification of this invention. It is sectional drawing which shows typically an example of the electronic device to which the waterproof sound-transmitting member of this invention was applied. It is a schematic diagram for demonstrating the evaluation method of the waterproof sound-transmitting member used in an Example. It is a top view which shows another Example of the waterproof sound-transmitting member of this invention schematically. It is a top view which shows another Example of the waterproof sound-transmitting member of this invention schematically. It is a top view which shows an example of the conventional waterproof sound-transmitting member schematically.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a plan view of the waterproof sound transmitting member 1 of the present embodiment. FIG. 2 is a cross-sectional view of the waterproof sound transmitting member 1. In FIG. 1, the third adhesive layer 6 is not shown. The waterproof sound-transmitting member 1 includes a waterproof sound-transmitting film 2 and a support layer 3 adhered to the waterproof sound-transmitting film 2. The waterproof sound-transmitting membrane 2 is a membrane that allows sound to pass through and blocks the passage of water. The support layer 3 need only be adhered to at least one surface of the waterproof sound-transmitting film 2, and in the present embodiment, it is adhered only to one side (upper side of FIG. 2) of the waterproof sound-transmitting film 2. There is. The waterproof sound transmitting member 1 further includes a first adhesive layer 4, a second adhesive layer 5, and a third adhesive layer 6. The second adhesive layer 5 is provided on one side (upper side of FIG. 2) of the waterproof sound transmitting film 2, and the support layer 3 is adhered to the waterproof sound transmitting film 2. The third adhesive layer 6 is provided on one side (upper side of FIG. 2) of the support layer 3 and adheres the support layer 3 to the housing. The first adhesive layer 4 is provided on the other side (lower side of FIG. 2) of the waterproof sound transmitting film 2, and the waterproof sound transmitting film 2 is shown in an acoustic device (for example, the microphone 33 shown in FIG. 6 and FIG. 7). It is adhered to the speaker 45). The waterproof sound-transmitting member 1 is laminated in the order of a third adhesive layer 6, a support layer 3, a second adhesive layer 5, a waterproof sound-transmitting film 2, and a first adhesive layer 4.

As shown in FIG. 3, the waterproof sound transmitting member 1 may not have the third adhesive layer 6. Further, as shown in FIG. 4, the waterproof sound transmitting member 1 may further include a second support layer 7 and a fourth adhesive layer 8 on the first adhesive layer 4. The second support layer 7 is adhered to the other side (lower side of FIG. 4) of the waterproof sound transmitting film 2. The first adhesive layer 4 is provided on the other side (lower side of FIG. 4) of the waterproof sound transmitting film 2, and the waterproof sound transmitting film 2 is adhered to the second support layer 7. The fourth adhesive layer 8 is provided on the other side (lower side of FIG. 2) of the second support layer 7, and the second support layer 7 is shown in an acoustic device (for example, the microphone 33 shown in FIG. 6 and FIG. 7). It is adhered to the speaker 45). Further, as shown in FIG. 5, the waterproof sound transmitting member 1 may have a configuration in which the third adhesive layer 6 is removed from the configuration shown in FIG.

As shown in FIG. 1, the outer peripheral edge of the waterproof sound transmitting film 2 is a rectangle having a long side and a short side. When viewed along the direction in which sound passes, the support layer 3 has an outer peripheral edge that coincides with the outer peripheral edge of the waterproof sound-transmitting film 2. The support layer 3 has a frame portion 3A surrounding the internal region 10 and a connecting portion 3B connected to the frame portion 3A. The outer peripheral edge of the inner region 10 is a rectangle having a long side and a short side. The connecting portion 3B is arranged so as to divide the internal region 10 into a first opening 11 and a second opening 12. When the rectangle having the smallest area among the virtual rectangles tangent to the internal area 10 so as to include the internal area 10 is the first quadrangle 21, the ratio R1 of the long side to the short side of the first quadrangle 21 is 5 or more. Is. That is, the outer peripheral edge of the internal region 10 is an elongated rectangle. The distortion of the sound passing through the waterproof sound transmitting member 1 becomes remarkable when the ratio R1 is 5 or more and further 7 or more. In FIG. 1, the ratio R1 is represented by (D1 + E + D2) / C.

The outer peripheral ends of the first opening 11 and the second opening 12 are rectangles having long sides and short sides, respectively. In the present embodiment, the first opening 11 and the second opening 12 have the same shape. The lengths of the long side and the short side of the first opening 11 are the same as the lengths of the long side and the short side of the second opening 12, respectively. For each of the first opening 11 and the second opening 12, the rectangle having the smallest area among the virtual rectangles in contact with the openings 11 and 12 so as to include the openings 11 and 12 is the second quadrangle 22A. , 22B, the connecting portion 3B is arranged so that the ratio R2 of the long side to the short side of the second rectangles 22A and 22B is smaller than the ratio R1. That is, the outer peripheral ends of the openings 11 and 12 are rectangular, which are not elongated as compared with the outer peripheral ends of the internal region 10. The ratio R2 is preferably 4 or less, and more preferably 3.5 or less. The ratio R2 is a value of 1 or more according to the definition. When the ratio R2 is 1, the second quadrangles 22A and 22B are squares. In FIG. 1, the ratio R2 is represented by D1 / C or D2 / C.

The connecting portion 3B is arranged so as to divide the internal region 10 into a first opening 11 and a second opening 12. In the present embodiment, the connecting portion 3B is arranged so as to cross the internal region 10 along the center line O that equally divides the internal region 10 and connect the inner peripheral ends of the frame portion 3A. In the present embodiment, the connecting portion 3B extends perpendicular to the long side of the outer peripheral end of the inner region 10 and parallel to the short side of the outer peripheral end of the inner region 10. The ratio of the area of the connecting portion 3B to the area of the internal region 10 is preferably 0.3 or less. In other words, the ratio of the total area of two or more openings to the area of the internal region 10 (ratio of the total area of the openings 11 and 12) R3 is preferably 0.7 or more. The ratio R3 is more preferably 0.8 or more, and further preferably 0.9 or more. However, the ratio R3 is a value less than 1 according to the definition. A form in which the ratio R3 is large and the area of the connecting portion 3B is sufficiently small compared to the total area of the openings 11 and 12 is suitable for ensuring the sound permeability of the waterproof sound transmitting film 2.

The waterproof sound-transmitting film 2 has sound-transmitting regions 2A and 2B exposed from the openings 11 and 12. When viewed along the direction in which sound passes, the outer peripheral edges of the first adhesive layer 4, the second adhesive layer 5, and the third adhesive layer 6 coincide with the outer peripheral edges of the waterproof sound-transmitting film 2. The first adhesive layer 4, the second adhesive layer 5, and the third adhesive layer 6 each have two openings, and the adhesive layer 4 surrounding the two openings when viewed along the direction in which sound passes. The inner peripheral ends of, 5 and 6 coincide with the outer peripheral ends of the openings 11 and 12.

The length A of the short side of the outer peripheral end of the waterproof sound transmitting member 1 is preferably 2.0 mm or more and 30 mm or less, and the length B of the long side of the outer peripheral end of the waterproof sound transmitting member 1 is, for example, 4. It is preferably 0 mm or more and 60 mm or less. The length C of the short side of the outer peripheral end of the openings 11 and 12 is preferably 0.5 mm or more and 29 mm or less, and the lengths D1 and D2 of the long side of the outer peripheral end of the openings 11 and 12 are, for example. It is preferably 0.5 mm or more and 29 mm or less. The width E of the connecting portion 3B is preferably, for example, 0.5 mm or more and 20 mm or less. The length C of the short side of the outer peripheral end of the internal region 10 is preferably, for example, 0.5 mm or more and 29 mm or less. The length (D1 + E + D2) of the long side of the outer peripheral end of the internal region 10 is preferably, for example, 0.5 mm or more and 58 mm or less.

In the present embodiment, when viewed along the direction in which sound passes, the outer peripheral edge of the support layer 3 has an outer peripheral edge that coincides with the outer peripheral edge of the waterproof sound-transmitting film 2, but the outer peripheral edge of the waterproof sound-transmitting film 2 It may have an outer peripheral edge different from the edge. For example, the waterproof sound-transmitting film 2 may have an outer peripheral end located inside the outer peripheral end of the support layer 3 as long as it can cover the openings 11 and 12.

In the present embodiment, one connecting portion 3B is arranged in the waterproof sound transmitting member 1, but it is sufficient that at least one connecting portion is arranged, and two or more connecting portions may be arranged. As shown in FIG. 8, the waterproof sound transmitting member 1 may have two first connecting portions 3C and a second connecting portion 3D arranged. The first connecting portion 3C and the second connecting portion 3D are not in contact with each other. In this way, it is preferable that two or more connecting portions are arranged so as not to touch each other. As shown in FIG. 8, the first connecting portion 3C is arranged so as to divide the internal region 10 into the first opening 11 and the second opening 12. The second connecting portion 3D is arranged so as to divide the internal region 10 into the second opening 13 and the third opening 13.

The outer peripheral edges of the openings 11 to 13 are rectangular with long and short sides, respectively. The openings 11 to 13 have the same shape. The lengths of the long side and the short side of the first opening 11 are the same as the lengths of the long side and the short side of the second opening 12 and the lengths of the long side and the short side of the third opening 13. For each of the openings 11 to 13, when the rectangle having the smallest area among the virtual rectangles in contact with the openings 11 to 13 so as to include the openings 11 to 13 is the second quadrangle 22A to 22C. , The connecting portions 3C and 3D are arranged so that the ratio R2 of the long side to the short side of the second rectangles 22A to 22C is smaller than the ratio R1. That is, the outer peripheral ends of the openings 11 to 13 are rectangular, which are not elongated as compared with the outer peripheral ends of the internal region 10. Therefore, the distortion of the sound can be reduced as compared with the case where the internal region 10 is used as the sound passing region.

In FIG. 8, the ratio R1 is represented by (D3 + E1 + D4 + E2 + D5) / C. The ratio R2 is represented by D3 / C, D4 / C or D5 / C.

In the embodiment shown in FIG. 9, when viewed along the direction in which the sound passes, the inner peripheral end of the frame portion 3A surrounding the openings 11 and 13 is a substantially rectangular shape in which a part of the corner portion of the rectangle is rounded. It has become. The first quadrangle 21 is a rectangle having the smallest area among virtual rectangles tangent to the internal area 10 so as to include the internal area 10. The openings 11 to 13 have substantially the same shape. It is preferable that the connecting portion is arranged so that two or more openings have substantially the same shape.

Examples of the material of the waterproof sound-transmitting membrane 2 include a polymer material. Suitable polymer materials constituting the waterproof sound-transmitting membrane 2 include polyethylene (PE), polyimide (PI), polypropylene (PP), polyethylene terephthalate (PET), and polytetrafluoroethylene (PTFE). Further, the waterproof sound-transmitting membrane 2 is preferably made of a fluororesin, and specifically, a polytetrafluoroethylene-stretched porous membrane is particularly preferable. Further, the waterproof sound-transmitting film 2 may have a non-woven fabric aspect, or may be configured by aggregating nanofibers. Further, the waterproof sound transmitting film 2 may be subjected to a water repellent treatment.

The support layer 3 is adhered to the waterproof sound-transmitting film 2 to increase the rigidity of the waterproof sound-transmitting member 1. That is, the support layer 3 has an action of stabilizing the shape of the waterproof sound transmitting member 1. In the present embodiment, the support layer 3 has a film-like shape. The support layer 3 is preferably made of a foamed resin (resin foam). This is because it is suitable for suppressing sound distortion. Further, in the present embodiment, the material of the support layer 3 is a urethane-based resin foam. The material of the support layer 3 is not limited to the urethane-based resin foam, and may be a polyolefin-based resin foam. The polyolefin-based resin foam may be a resin foam containing only a polyolefin resin such as polyethylene (PE) or polypropylene (PP) as a resin component, but from the viewpoints of cushioning property, flexibility, high foaming ratio, etc., the polyolefin resin A foam containing a mixture of the resin and an elastomer component such as rubber or a thermoplastic elastomer as a resin component is preferable.

For the first adhesive layer 4, the second adhesive layer 5, and the third adhesive layer 6, a double-sided adhesive tape using an acrylic-based or silicone-based adhesive is used. Alternatively, the first adhesive layer 4, the second adhesive layer 5, and the third adhesive layer 6 may be composed of only the adhesive.

FIG. 6 shows a mobile phone 30 as an example of an electronic device to which the waterproof sound transmitting member 1 is applied.

The microphone 33 is housed in the housing 38 of the mobile phone 30. The housing 38 is provided with a first sound collecting port 39 that guides sound from the outside to the microphone 33. A sound collecting unit 34 that converts voice into an electric signal is housed in the package 35 of the microphone 33. The package 35 is a rectangular parallelepiped with a hollow inside, and on one surface of the package 35, the sound introduced from the first sound collecting port 39 of the housing 38 is guided to the sound collecting portion 34 of the microphone 33. A mouth 36 is provided. The first sound collecting port 39 and the second sound collecting port 36 are provided at positions where sound can be passed through the waterproof sound transmitting film 2 while being separated by the waterproof sound transmitting film 2. The microphone 33 is electrically connected to the circuit board 31 of the mobile phone 30 by a terminal (not shown) provided on the bottom surface of the package 35, and the electric signal converted from the sound by the sound collecting unit 34 is generated. It is output to the circuit board 31 via the terminals. In the mobile phone 30, the microphone 33 is collected from the first sound collecting port 39 and the second sound collecting port 36 by the waterproof sound transmitting film 2 arranged so as to separate the first sound collecting port 39 and the second sound collecting port 36. Sound can be passed through the sound collecting unit 34 while preventing foreign matter such as dust and water from entering the sound unit 34, and the performance of the microphone 33 is ensured while preventing the generation of noise and its failure in the microphone 33. it can.

(Example 1)
The PTFE stretched porous sheet (Nitto Denko Co., Ltd., NTF610AP) and the urethane foam resin sheet PORON (registered trademark) SR-S 48P (Roger Suinoac Co., Ltd.) have the shapes shown in FIG. 1 (waterproof sound-permeable membrane and support). The length A of the short side of the outer shape of the layer is 7 mm, the length B of the long side of the outer shape of the waterproof sound absorbing membrane and the support layer is 25 mm, and the length of the inner short side of the first opening and the second opening. C is 2.8 mm, the lengths of the long sides of the inner shape of the first opening and the second opening are 9.9 mm, and the length E of the short side of the outer shape of the connecting portion is 1.5 mm). By punching using a Thomson mold as described above, a waterproof sound-transmitting film and a support layer were produced. By laminating the first double-sided adhesive tape, the support layer, the second double-sided adhesive tape, the waterproof sound-permeable film, and the third double-sided adhesive tape in this order, a waterproof sound-transmitting member having the structure shown in FIG. 2 was produced. .. The thickness of the first to third double-sided adhesive tapes was 0.05 mm, and the base material was made of PET.

(Example 2)
The shape shown in FIG. 8 for the PTFE porous sheet and the urethane-based foamed resin sheet (the length A of the short side of the outer shape of the waterproof sound-permeable membrane and the support layer is 7 mm, and the length of the long side of the outer shape of the waterproof sound-transmitting membrane and the support layer). B is 25 mm, the length C of the short side of the inner shape of the first opening, the second opening and the third opening is 2.8 mm, and the inside of the first opening, the second opening and the third opening. A Thomson type is used so that the lengths of the long sides of the shape D3, D4 and D5 are 6.6 mm, and the lengths of the short sides of the outer shapes of the first connecting portion and the second connecting portion are 1.0 mm). A waterproof sound-transmitting member was produced by the same procedure as in Example 1 except that the waterproof sound-transmitting film and the support layer were produced by punching.

(Comparative Example 1)
The shape shown in FIG. 10 for the PTFE porous sheet and the urethane foam resin sheet (the length A of the short side of the outer shape of the waterproof sound-permeable membrane and the support layer is 7 mm, and the length of the long side of the outer shape of the waterproof sound-transmitting membrane and the support layer). Thomson type so that the length B is 25 mm, the length C of the short side of the inner shape of the first opening is 2.8 mm, and the length D of the long side of the inner shape of the first opening is 19.8 mm). A waterproof sound-transmitting member was produced by the same procedure as in Example 1 except that a waterproof sound-transmitting film and a support layer were produced by punching using the material.

Harmonic distortion was examined for the waterproof sound-transmitting members of Example 1, Example 2, and Comparative Example 1 as follows.

[Harmonic distortion]
Harmonic distortion in the waterproof sound-transmitting member was measured as follows.

First, as shown in FIG. 7, a simulated housing 41 (made of acrylic, length 70 x width 50 x height 15 mm) imitating a mobile phone housing was prepared. The simulated housing 41 is composed of a first portion 41a and a second portion 41b, and the first portion 41a and the second portion 41b can be fitted to each other. A mounting hole 42 is provided in the first portion 41a. By fitting the first portion 41a and the second portion 41b to each other, a space is formed in the simulated housing 41 in which there is no opening other than the mounting hole 42 and the conduction port 43 of the lead wire 44.

Separately from this, the third double-sided adhesive tape of the waterproof sound-transmitting member produced in each Example and Comparative Example was attached to the speaker 45 (manufactured by Star Micronics, SCM-09C-J) as a sound source.

Next, the speaker 45 to which the waterproof sound-transmitting member is attached faces the mounting hole 42 in the first portion 41a of the simulated housing 41, the waterproof sound-transmitting member faces the mounting hole 42, and the waterproof sound-transmitting member faces the mounting hole 42. It was fixed from the inner surface when it was fitted with the second portion 41b so as to close the. The speaker 45 is fixed to the first portion 41a with a first double-sided adhesive tape (third adhesive layer 6) attached to the surface of the waterproof sound-transmitting member opposite to the speaker 45 side. Care was taken not to let the first double-sided adhesive tape cover the mounting hole 42, and to completely block the mounting hole 42 with the waterproof sound-transmitting member.

Next, while guiding the lead wire 44 of the speaker 45 to the outside of the simulated housing 41 through the conduction port 43, the first portion 41a and the second portion 41b are fitted together, and the harmonic distortion of the waterproof sound transmitting member is measured. A simulated housing 41 was formed for this purpose. The conduction port 43 was closed with putty after the lead wire 44 was led out.

Next, the lead wire 44 and the microphone (Type 2669 manufactured by B & K Co., Ltd.) were connected to the sound transmissibility evaluation device (3560-B-030 manufactured by B & K Co., Ltd.), and the microphone was arranged at a position 50 mm away from the speaker 45.

With the waterproof sound-transmitting member installed as described above, SSR analysis (steady state response analysis, test signal 20 Hz to 20 kHz, sweep) was selected and executed as the evaluation method of the sound-permeable evaluation device, and the waterproof sound-transmitting film was formed. Harmonic distortion was measured. Specifically, the harmonic distortion represented by the sum of the sounds of the 12th to 100th harmonics in the sound of the fundamental wave of 200 to 800 Hz was measured.

The results of measuring the harmonic distortion of the waterproof sound-transmitting member as described above are the ratio R1 of the long side to the short side of the first quadrangle, the ratio R2 of the long side to the short side of the second quadrangle, and the area of the internal area. It is shown in Table 1 together with the ratio R3 of the total area of the openings to.

In Examples 1 and 2, the ratio R1 was 5 or more, the ratio R2 was smaller than the ratio R1, and it was 4 or less. In Examples 1 and 2, the outer peripheral edge of each opening was a rectangle that was not elongated as compared to the outer peripheral edge of the internal region. In Comparative Example 1, the ratio R1 is 5 or more, and the ratio R2 is equal to the ratio R1. In Comparative Example 1, the outer peripheral edge of the opening was an elongated rectangle. As a result, the harmonic distortion in Examples 1 and 2 is smaller than the harmonic distortion in Comparative Example 1. Therefore, the waterproof sound-transmitting members of Examples 1 and 2 were able to reduce the distortion of sound as compared with the waterproof sound-transmitting member of Comparative Example 1.

The waterproof sound-transmitting membrane of the present invention can be suitably used for an electronic device in which an acoustic device is housed. Specifically, it can be suitably used for mobile phones, notebook computers, smartphones, portable audio equipment, portable game devices, and the like.

1 Waterproof sound-transmitting member 2 Waterproof sound-transmitting film 2A 1st sound-transmitting area 2B 2nd sound-transmitting area 3 Support layer 3A Frame part 3B Connecting part 3C 1st connecting part 3D 2nd connecting part 4 1st adhesive layer 5 2nd adhesive Layer 6 Third adhesive layer 7 Second support layer 8 Fourth adhesive layer 10 Internal area 11 First opening 12 Second opening 13 Third opening 21 First quadrangle 22A-22C Second quadrangle

Claims (6)

A waterproof sound-transmitting member attached to an opening of a housing and facing a speaker or a microphone housed in the housing .
Waterproof sound-permeable membrane and
A support layer adhered to the waterproof sound-transmitting film and
An adhesive layer for adhering the support layer to the housing is provided.
The support layer has a frame portion surrounding the internal region and at least one connecting portion connected to the frame portion so as to divide the internal region into two or more openings.
When the rectangle having the smallest area among the virtual rectangles in contact with the internal area so as to include the internal area is set as the first quadrangle, the ratio R1 of the long side to the short side of the first quadrangle is 5 or more. Yes,
For each of the two or more openings, when the rectangle or square having the smallest area among the virtual rectangles or squares in contact with the openings so as to include each opening is defined as the second quadrangle, the second as the ratio of the long side to the short side of the rectangle R2 is smaller than the ratio R1, the at least one connecting portion is disposed, a waterproof sound-transmitting member. The waterproof sound-transmitting member according to claim 1, wherein the ratio R2 is 4 or less. Two or more connecting portions are arranged as the at least one connecting portion.
The waterproof sound-transmitting member according to claim 1 or 2, wherein the two or more connecting portions are arranged so as not to come into contact with each other. The waterproof sound-transmitting member according to any one of claims 1 to 3, wherein the at least one connecting portion is arranged so that the two or more openings have substantially the same shape. The waterproof sound-transmitting member according to any one of claims 1 to 4, wherein the support layer is made of a foamed resin. The waterproof sound-transmitting member according to any one of claims 1 to 5, wherein the waterproof sound-transmitting membrane is a polytetrafluoroethylene-stretched porous membrane.

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