JP2005334758A - Ventilation filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ventilation filter provided with a water-proofing property, a ventilation or sound transmission property, and an electromagnetic wave shielding property. <P>SOLUTION: The ventilation filter 1 of this invention is a laminate containing at least one layer of a water-repelling resin porous film 2 and the laminate includes a conductive ventilation layer 3. Another ventilation filter of this invention is a ventilation filter containing at least one layer of a water-repelling resin porous film and a conductive substance adheres to at least one layer of the water-repelling resin porous film. The ventilation filter 1 preferable further includes a ventilation support layer overlayering the water-repelling resin porous film and the water-repelling resin porous film is preferable to include a PTFE (polytetrafluoroethylene) porous film. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a ventilation filter that is attached to an opening of a casing of an electronic device and has waterproofness, dustproofness, sound permeability, air permeability, and the like.

  A housing of an electronic device such as a precision device has an opening for propagation of sound, release of gas generated inside the housing, relaxation of pressure change inside the housing due to temperature change, and the like. In particular, in portable information communication devices such as mobile phones, notebook computers, or electronic notebooks, sound generators and sound receivers such as speakers, receivers, microphones, etc. need to have a high sound transmission capability in terms of their functions. Inevitably a large opening. These openings are covered with a ventilation filter such as a water-repellent nonwoven fabric, a water-repellent net, and a thin plastic film in order to prevent failure of the electronic device due to the ingress of water or dust.

As a material suitable for the ventilation filter, a water-repellent resin porous membrane (hereinafter referred to as “water-repellent resin porous membrane”), for example, polytetrafluoroethylene (hereinafter referred to as “PTFE”) porous membrane. (For example, refer to Patent Document 1). The water-repellent resin porous membrane has high breathability or sound permeability and waterproofness.
JP-A-10-165787 (2 pages)

  In recent years, due to an increase in wireless devices and the like, the opportunity for electromagnetic waves to enter the housing has increased. In order to prevent electromagnetic waves from entering the casing, the casing 7 is usually made of a conductive material, but electromagnetic waves enter through the opening and adversely affect the operation of the electronic device. Is a problem.

  The ventilation filter of the present invention is a laminate including at least one water-repellent resin porous membrane, and the laminate includes a conductive ventilation layer.

  Another vent filter of the present invention is a vent filter including at least one layer of water-repellent resin porous membrane, and at least one layer of the water-repellent resin porous membrane of the at least one layer of water-repellent resin porous membrane. A conductive substance is attached to the film.

  In the present invention, it is possible to provide a ventilation filter having waterproofness, breathability or sound permeability, and electromagnetic shielding properties.

  Hereinafter, an example of the ventilation filter of the present invention will be described with reference to the drawings.

(Embodiment 1)
As shown in FIG. 1, the ventilation filter 1 of the present embodiment is a laminate including at least one water-repellent resin porous film 2, and the laminate includes a conductive ventilation layer 3. Since the ventilation filter 1 includes the conductive ventilation layer 3, if the ventilation filter 1 is attached to the opening of the housing, a shield against electromagnetic waves can be imparted to the opening of the housing, and the adverse effect of the electromagnetic waves on the electronic device can be prevented. Can be reduced.

  In the ventilation filter 1 of the present embodiment, since one surface of the ventilation filter 1 (laminated body) is formed from one surface of the conductive ventilation layer 3, ventilation is performed with the one surface facing the housing. If the filter 1 is attached to the opening of the housing, an effective shield against electromagnetic waves can be imparted to the opening of the housing.

  The material of the conductive air-permeable layer 3 is not particularly limited as long as it contains a conductive substance. For example, the conductive gas-permeable layer 3 is made of metal such as gold, silver, copper, platinum, aluminum, iron, nickel, carbon black, and graphite. It is preferable that at least one conductor selected from the group is included. For example, the metal simple substance, the composite material containing the conductor and the resin, for example, metal plating fiber may be used. Examples of the resin include polyolefins such as polyester, polyethylene (PE), and polypropylene (PP), and polyamide.

The form of the conductive air-permeable layer 3 is not particularly limited, but is preferably higher in air permeability than the water-repellent resin porous membrane 2, for example, a nonwoven fabric, a net (mesh-like sheet), or a woven fabric. . When the conductive air-permeable layer 3 is, for example, a nonwoven fabric, the basis weight is preferably 30 to 100 g / m ² and the thickness is preferably 0.05 to 0.3 mm. As shown in FIG. 2, when the conductive air-permeable layer 3 is a net having a plurality of openings 3a, the average area of the openings 3a (average area of each opening) is 0.0001 to 0.01 mm. ² and the aperture ratio is preferably 40 to 70%. This is because the use of the conductive air-permeable layer 3 having the above-described configuration makes it possible to achieve both appropriate air permeability or sound permeability and good shielding properties against electromagnetic waves. In the present invention, the weight per unit area and the aperture ratio are values obtained by the following method.

(1) Weight per unit area 100 cm ² of the conductive air-permeable layer 3 was sampled, and the weight was measured with an electronic balance to determine the mass (g) per 1 m ² .

(2) Aperture ratio Aperture ratio = [total area of openings / area of entire net] × 100
The material of the water-repellent resin porous membrane 2 is not particularly limited as long as it includes a material having water repellency, but for example, preferably contains a fluororesin. Examples of the fluororesin include PTFE, polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-ethylene copolymer, and the like. In particular, the water-repellent resin porous membrane 2 is preferably a PTFE porous membrane that can maintain air permeability even in a small area and has a high function of preventing water and dust from entering the inside of the housing.

The form of the water-repellent resin porous membrane 2 is not particularly limited, but is usually 5 to 300 μm in thickness, 0.1 to 5 μm in average pore diameter, 60 to 95% in porosity, and air permeability (fragile ventilation). A film having a degree of 0.01 to 20 cc / cm ² · sec is suitable. The air permeability is a value measured using a Frazier tester (manufactured by Toyo Seiki Seisakusho) according to JIS L 1096 (6.27.A method).

  The water-repellent resin porous membrane described above can be produced by a conventionally used method. An example of the production method will be described below by taking a PTFE porous membrane as an example.

  First, a paste-like mixture obtained by adding a liquid lubricant to PTFE fine powder is preformed. The liquid lubricant is not particularly limited as long as it can wet the surface of the PTFE fine powder and can be removed by extraction or heating. For example, hydrocarbons such as naphtha and white oil can be used. The addition amount of the liquid lubricant is suitably about 5 to 50 parts by weight with respect to 100 parts by weight of PTFE fine powder. The above preforming is performed at a pressure that does not squeeze out the liquid lubricant. Next, the preformed body is extruded and / or rolled to form a sheet, and the sheet-like formed body thus obtained is stretched at least in a uniaxial direction to obtain a PTFE porous membrane. The stretching may be performed after removing the liquid lubricant. Stretching conditions can be set as appropriate. Usually, the temperature is 30 to 320 ° C., and the stretching ratio is 2 to 30 times in both the longitudinal and transverse directions. In addition, if the PTFE porous membrane after stretching is heated and fired to a melting point of PTFE or higher, the strength can be increased.

  The conductive air-permeable layer 3 and the water-repellent resin porous membrane 2 may be simply overlapped or joined together. Joining can be performed by a method such as adhesion using an adhesive such as a pressure-sensitive adhesive or a thermosetting adhesive, or heat welding, but the breathability or sound permeability of the ventilation filter 1 is impaired during the joining. It is necessary to be careful not to. Specifically, it is preferable that the conductive air-permeable layer 3 and the water-repellent resin porous film 2 are bonded to each other by applying the adhesive to the conductive air-permeable layer 3 in the form of dots or nets. Alternatively, when the ventilation filter 1 is cut into a predetermined shape, the conductive ventilation layer 3 and the water-repellent resin porous membrane 2 are joined only at the peripheral edge of the cut ventilation filter 1. An adhesive may be applied to the conductive ventilation layer 3.

  In the example shown in FIG. 1, the ventilation filter 1 includes a conductive ventilation layer 3 and a water-repellent resin porous film 2, but in order to improve strength and handling properties, as shown in FIG. A breathable support layer 4 laminated on the porous membrane 2 may be further included.

The material, structure, and form of the breathable support layer 4 are not particularly limited. However, the breathable support layer 4 has a higher breathability than that of the water-repellent resin porous membrane 2, for example, non-woven fabric, woven fabric, net, sponge, foam, and other porous materials. It is preferable to use a material. In particular, a nonwoven fabric is preferable from the viewpoint of strength, flexibility, and workability. There is no restriction | limiting in particular about the material of the air permeable support layer 4, Polyolefin (PE, PP, ultra high molecular weight polyethylene (UHMWPE) etc.), polyamide, polyester (polyethylene terephthalate (PET) etc.), aromatic polyamide, or these composite materials Etc. can be used. When the breathable support layer 4 is, for example, a nonwoven fabric, the weight per unit area is usually 30 to 100 g / m ² , the thickness is 0.05 to 0.3 mm, and the net has a plurality of openings. The average area of the openings (average area of the individual openings) is preferably 0.0001 to 0.01 mm ² and the opening ratio is preferably 40 to 70%.

  The breathable support layer 4 and the water-repellent resin porous membrane 2 may be simply overlapped or joined together. Joining can be performed by methods such as adhesive laminating, thermal laminating, heat welding, ultrasonic welding, vibration welding, and adhesion using an adhesive. For example, when laminating by thermal lamination, a part of the breathable support layer 4 may be melted and bonded by heating. Moreover, you may adhere | attach by interposing a fusing agent like hot melt powder.

  The ventilation filter 1 may be subjected to liquid repellent treatment such as water repellent treatment and oil repellent treatment as necessary. The liquid repellent treatment can be performed by applying a substance having a small surface tension, curing it after drying. The liquid repellent is not particularly limited as long as a film having a lower surface tension than the water repellent resin porous film 2 can be formed, but a polymer having a perfluoroalkyl group is suitable. Such polymers include, for example, “Florard” (manufactured by Sumitomo 3M), “Scotch guard” (manufactured by Sumitomo 3M), “Tex Guard” (manufactured by Daikin Industries), “Unidyne” (manufactured by Daikin Industries), “Asahi” “Guard” (manufactured by Asahi Glass) and the like (all trade names) may be used. The liquid repellent may be applied by impregnation or spraying. The amount of the liquid repellent applied is preferably adjusted so that a sufficient liquid repellent effect is obtained and the air permeability of the air filter 1 is not hindered. The liquid repellent treatment may be performed only on the water-repellent resin porous membrane 2 or on the entire ventilation filter 1.

  Although there is no restriction | limiting in particular about the attachment method to the housing | casing 7 of the ventilation filter 1, For example, the screwing with a metal screw, the fitting of the metal frame etc. which were provided in the periphery of the ventilation filter 1, and a housing | casing, a thermoplastic resin It can be carried out by adhesion with a system adhesive or an adhesive tape.

  Considering the reliability and simplicity of short circuiting and attachment to the housing 7, the ventilation filter 1 has a shape that can cover the opening 8 of the housing 7, as shown in FIG. It is preferable that the air-permeable filter 1 is attached to the housing 7 by the conductive adhesive layer 5 including the conductive adhesive layer 5 disposed on the periphery of one surface of the conductive air-permeable layer 3.

  As the material for the conductive adhesive layer 5, for example, a pressure sensitive adhesive in which a conductive substance is mixed in an acrylic viscoelastic polymer can be used. As the conductive material, for example, at least one conductive material selected from the group consisting of powdered or fibrous gold, silver, copper, platinum, aluminum, iron, nickel, and the like, carbon black, and graphite can be used. . If the pressure sensitive adhesive is processed into a donut shape to form an adhesive tape, and the adhesive tape is disposed on the periphery of one surface of the conductive ventilation layer 3, the ventilation filter 1 can be easily short-circuited and attached to the housing 7. Thus, an effective shield against electromagnetic waves can be imparted to the opening 8 of the housing 7.

  The conductive adhesive layer 5 is composed of conductive small protrusions (not shown) formed on one surface of the conductive air-permeable layer 3 and a pressure-sensitive adhesive disposed so as to surround the small protrusions. It may be.

(Embodiment 2)
As shown in FIG. 5, the ventilation filter 21 of the present embodiment includes a single layer of the water-repellent resin porous film 2, and the conductive substance 6 is attached to the water-repellent resin porous film 2. In the ventilation filter 21, the conductive substance 6 adheres to the water-repellent resin porous membrane 2. Therefore, if the ventilation filter 21 is attached to the opening of the casing, a shield against electromagnetic waves can be provided to the opening of the casing. , The adverse effects of electronic waves on electronic equipment can be reduced.

  The material, structure, and form of the water-repellent resin porous membrane 2 are the same as those in the first embodiment. In the ventilation filter 21, since the conductive substance 6 adheres to at least one surface of the water-repellent resin porous membrane 2 having an average pore diameter of 0.1 to 5 μm and the pores, the shielding property against electromagnetic waves is high.

  In the example shown in FIG. 5, the ventilation filter 21 has a structure in which the conductive material 6 is attached to a single layer of the water-repellent resin porous membrane 2, but the ventilation filter 21 of the present embodiment is not limited to this. For example, as shown in FIG. 6, a breathable support layer 4 that is laminated on the water-repellent resin porous membrane 2 and reinforces the water-repellent resin porous membrane 2 may be further included. The conductive material 6 may also adhere to the support layer 4. The material, structure, and form of the breathable support layer 4 are the same as those in the first embodiment.

  In the example shown in FIGS. 5 and 6, the ventilation filter 21 has one surface formed from one surface of the water-repellent resin porous membrane 2 to which the conductive substance 6 is attached. Since the conductive substance 6 adheres to at least the one surface and the hole of the porous membrane 2, the ventilation filter 21 is placed in the opening of the housing with the one surface of the ventilation filter 21 facing the housing. If attached, an effective shield against electromagnetic waves can be imparted to the opening of the housing.

  The conductive material 6 is not particularly limited as long as it is a conductive material. However, the conductive material 6 is a powder or fibrous metal such as gold, silver, copper, platinum, aluminum, iron, nickel, carbon black, and graphite. It is preferable that it is at least 1 sort (s) of conductors chosen from these. When the conductive material 6 is in a powder form, the average particle diameter is 0.01 to 1 μm, and when it is fibrous, the average fiber length is 0.1 to 10 μm and the average fiber diameter is 0. It is preferably 0.01 to 1 μm. For example, when the average pore size of the water repellent resin porous membrane 2 is 0.5 μm to 5 μm, the conductive material 6 within the above range is suitable.

  Method of attaching conductive substance 6 to water-repellent resin porous membrane 2 alone or a laminate including water-repellent resin porous membrane 2 and air-permeable support layer 4 (hereinafter referred to as “water-repellent resin porous membrane 2 etc.”) For example, (1) a method in which the conductive substance 6 is sprayed as it is onto the water-repellent resin porous membrane 2 or the like, and (2) a dispersion in which the conductive substance is dispersed in a dispersion medium such as alcohol is used. A method of drying and removing the dispersion medium from the water-repellent resin porous membrane 2 etc. after spraying on the membrane 2 etc., (3) After immersing the water-repellent resin porous membrane 2 etc. in the dispersion liquid, Examples thereof include a method of drying and removing the dispersion medium from the porous membrane 2 and the like.

  When the dispersion medium is dried and removed from the water-repellent resin porous membrane 2 etc. after the water-repellent resin porous membrane 2 etc. is immersed in the dispersion, the water-repellent resin porous membrane 2 etc. and these are immersed. It is preferable to impregnate the water-repellent resin porous membrane 2 or the like with the conductive substance 6 while vibrating the dispersion with ultrasonic waves. This is because the uniformity of the conductive material 6 in the ventilation filter is increased, and a ventilation filter having high electromagnetic shielding properties can be provided.

  The dispersion medium is preferably a water-repellent resin porous membrane 2 that is easily wetted and has good dispersibility of the conductive material 6, for example, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, an aqueous surfactant solution, a fluorine-based solvent, or the like. .

  The adhesion amount of the conductive material 6 is preferably 10 to 40% by weight of the weight of the water repellent resin porous membrane 2 and the like. If the amount is too small, a sufficient electromagnetic shielding effect cannot be obtained. If the amount is too large, the pores of the water-repellent resin porous membrane 2 are excessively blocked, and there is a possibility that air permeability or sound permeability may be reduced. Further, if the amount of the conductive material 6 attached is within the above-described range, even if the pores of the water-repellent resin porous membrane 2 are blocked to some extent by the conductive material 6, there is no effect on the air permeability or sound permeability. .

  Also in the ventilation filter 21 of the present embodiment, liquid repellent treatment may be performed as necessary, as in the first embodiment.

  The method of attaching the ventilation filter 21 to the housing 7 is not different from that of the first embodiment. As shown in FIG. 7, the ventilation filter 21 has a shape that can cover the opening 8 and is electrically conductive. If the conductive adhesive layer 5 disposed on the periphery of one surface of the water-repellent plastic porous membrane 2 to which the conductive material 6 is attached is further included, the ventilation filter 21 can be easily short-circuited and attached to the housing 7. An effective shield against electromagnetic waves can be imparted to the opening 8 of the housing 7.

  Hereinafter, an example of the ventilation filter of the present invention will be described more specifically with reference to examples.

PTFE porous membrane (thickness 15 μm, porosity 90%, average pore diameter 5 μm, fragile air permeability 7 cc / cm ² · sec) and core-sheathed nonwoven fabric (weight per unit area 30 g / m ² , thickness 0.1 mm, core The component PP and the sheath component PE) were heat-laminated by a pair of heat rolls (roll temperature 200 ° C.). Next, an acrylic pressure-sensitive adhesive is bonded to a non-woven fabric (made by Seiren Co., Si-80-301, basis weight 45 g / m ² , thickness 0.07 mm) made of a metal-plated fiber having a core component of polyester and a sheath component of nickel. The agent was applied in several spots, and a non-woven fabric made of metal-plated fibers and a PTFE porous membrane laminated with a polyolefin non-woven fabric were bonded together to obtain a ventilation filter A. This vent filter A is punched into a predetermined shape, and a conductive pressure-sensitive adhesive processed into a donut shape (manufactured by Nippon Ink Co., Ltd., # 8350AD) is attached to the periphery of one surface of a nonwoven fabric made of metal-plated fibers A conductive adhesive layer was formed.

PTFE porous membrane (thickness 15 μm, porosity 90%, average pore diameter 5 μm, fragile air permeability 7 cc / cm ² · sec) and core-sheathed nonwoven fabric (weight per unit area 30 g / m ² , thickness 0.1 mm, core The component PP and the sheath component PE) were heat laminated with a pair of hot rolls (roll temperature 200 ° C.). Next, a dispersion liquid in which 20 g of highly conductive carbon black (manufactured by Lion Corporation, “Ketjen Black EC”, specific surface area 1000 m ² / g) was dispersed in 1 liter of ethanol was prepared. The dispersion was placed in a metal ultrasonic vibration vessel, and a porous PTFE membrane laminated with a core-sheath nonwoven fabric was immersed for 1 minute while applying ultrasonic vibration of 28 kHz, and then pulled up from the dispersion. The ventilation filter B was obtained by drying in an atmosphere of 5 ° C. for 5 minutes. The amount of carbon black attached was 25% by weight of the weight of the laminate composed of the core-sheath nonwoven fabric and the PTFE porous membrane.

  The air filter B obtained in Example 2 was immersed for 5 seconds in a water / oil repellent with a solid content of 5% by weight obtained by diluting “Unidyne TG-725” (manufactured by Daikin Industries) with toluene. Heating at 3 ° C. for 3 minutes yielded a breathable filter C that had been treated to be water and oil repellent. The ventilation filter C is punched into a predetermined shape, and a conductive pressure-sensitive adhesive (Nippon Ink Co., Ltd., # 8350AD) processed into a donut shape is attached to the periphery of one surface of a nonwoven fabric made of metal-plated fibers to conduct An adhesive layer was formed.

(Comparative Example 1)
A ventilation filter D was obtained in the same manner as in Example 1 except that a non-woven fabric made of metal-plated fibers was not provided.

(Comparative Example 2)
Solid content 5 obtained by diluting “Unidyne TG-725” (manufactured by Daikin Kogyo Co., Ltd.) with toluene, a non-woven fabric (Seren Co., Si-80-301) made of a metal-plated fiber whose core component is polyester and whose sheath component is nickel. It was immersed in a weight% water / oil repellent treatment agent for 5 seconds, taken out, and then heated at 130 ° C. for 3 minutes to obtain a breathable filter E subjected to water / oil repellent treatment.

  The ventilation filters A to E were examined for electromagnetic wave shielding properties, waterproof properties, breathability and sound permeability by the methods shown below, and the results are shown in Table 1.

  [Electromagnetic wave shielding property] The electromagnetic wave shielding property was evaluated by the KEC method. The KEC method is a method developed at the Ikoma Radio Measurement Station of the Kansai Electronics Industry Promotion Center, which measures the shielding effect of materials in the near field. A spectrum analyzer was used as a measuring apparatus, and the electric field value attenuation (dB) was measured by continuously sweeping the frequency from 1 MHz to 1000 MHz. When the attenuation was 10 dB or more, it was judged as good (◯), and when it was less than 10 dB, it was judged as bad (x).

  [Waterproofness] The waterproofness was measured by applying a water pressure of 98 kPa (corresponding to 10 times the water pressure at a depth of 1 m) to a ventilation filter set in a stainless steel holder, and measuring the time when water leakage occurred. When no water leak occurred for 2 hours, it was judged that there was no water leak (O).

[Breathability] Measured according to JIS L 1096 (6.27.A method) using a Frazier tester (manufactured by Toyo Seiki Seisakusho). When the fragile air permeability was ² cc / cm ² · sec or more, it was judged as good (◯), and when the air permeability was less than ² cc / cm ² · sec, it was judged as poor (x).

  [Sound permeability] The sound permeability was measured by the following procedure using the sound permeability measurement chamber shown in FIG. The sound-transmitting measurement chamber is composed of a reverberation chamber 9 and an anechoic chamber 10, and an opening 11 (280 × 280 mm) is provided between the reverberation chamber 9 and the anechoic chamber 10. A sample 12 of a ventilation filter was stretched in the opening 11 so that the PTFE stretched porous membrane surface was on the reverberation chamber 9 side. The reverberation chamber 9 is provided with a speaker 41 and a microphone 42. The reverberation chamber 9 was saturated with uniform white noise in the entire frequency band of 250 to 10000 Hz. The sound pressure in each frequency band was 90 dB. The anechoic chamber 10 is provided with a microphone 51 at a position 70 mm from the film surface of the sample 7. In this embodiment, the sound pressure at 4000 Hz was measured. 4000 Hz is a frequency at which the human ear has the best sensitivity. The notation unit of sound pressure is decibel (dB). The amount of sound pressure loss obtained from the sound pressure measurement result in the anechoic chamber 10 is shown using sound transmission loss (hereinafter referred to as TL). TL is obtained from the following equation. The smaller the TL, the higher the air permeability and the better the performance as a ventilation filter. When TL was 5 dB or less, it was judged as good (◯), and when TL was larger than 5 dB, it was judged as bad (×).

  TL = (Sound pressure when opening is opened) − (Sound pressure when a sample is stretched over the opening)

  As shown in Table 1, in a ventilation filter including at least a water repellent resin porous membrane and a conductive ventilation layer, or a ventilation filter including a water repellent resin porous membrane to which a conductive substance is adhered, It was confirmed that sound permeability and electromagnetic shielding properties were good.

  The ventilation filter of the present invention is useful as a ventilation filter because it is waterproof, breathable or sound permeable, and has electromagnetic shielding properties.

Sectional drawing which shows an example of the ventilation filter of this invention The figure explaining the net used as a conductive ventilation layer Sectional drawing which shows the other example of the ventilation filter of this invention Sectional drawing explaining the state in which the other example of the ventilation filter of this invention was attached to the opening part of the housing | casing Sectional drawing which shows the other example of the ventilation filter of this invention Sectional drawing which shows the other example of the ventilation filter of this invention Sectional drawing explaining the state in which the other example of the ventilation filter of this invention was attached to the opening part of the housing | casing The figure which illustrates typically the method to measure the sound permeability of a ventilation filter in the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,21 Ventilation filter 2 Water repellent resin porous film 3 Conductive ventilation layer 3a Opening 4 Breathable support layer 5 Conductive adhesive layer 6 Conductive substance 7 Housing 8 Opening of housing

Claims (11)

  A ventilation filter comprising at least one water-repellent resin porous membrane, wherein the laminate includes a conductive ventilation layer.   The ventilation filter according to claim 1, wherein one surface of the laminate is formed from one surface of the conductive ventilation layer.   The ventilation filter according to claim 2, wherein a conductive adhesive layer is formed on a peripheral edge of the one surface of the conductive ventilation layer.   The ventilation filter according to any one of claims 1 to 3, wherein the conductive ventilation layer includes at least one conductor selected from the group consisting of metal, carbon black, and graphite.   The ventilation filter according to any one of claims 1 to 4, wherein the conductive ventilation layer is a nonwoven fabric, a net, or a woven fabric.   A ventilation filter including at least one water-repellent resin porous membrane, wherein a conductive substance adheres to at least one water-repellent resin porous membrane of the at least one water-repellent resin porous membrane. Ventilation filter characterized by being.   One surface is formed from one surface of the water-repellent resin porous membrane to which the conductive material is adhered, and the conductive material is present in at least the one surface and the hole of the water-repellent resin porous membrane. The ventilation filter according to claim 6, to which is attached.   The ventilation filter according to claim 7, wherein a conductive adhesive layer is formed on a peripheral edge of the one surface of the water-repellent resin porous membrane.   The ventilation filter according to any one of claims 6 to 8, wherein the conductive substance is at least one kind of conductor selected from the group consisting of metal, carbon black, and graphite.   The ventilation filter according to any one of claims 1 to 9, further comprising a breathable support layer laminated on the water-repellent resin porous membrane.   The ventilation filter according to any one of claims 1 to 10, wherein the water-repellent resin porous membrane includes a polytetrafluoroethylene porous membrane.

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