JP2011115687A - Ventilation filter, method of fixing the ventilation filter, and method for manufacturing electric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ventilation filter with a form suited to prevention of peel of a first adhesive layer when peeling a protective film from a second adhesive layer. <P>SOLUTION: The ventilation filter includes the first adhesive layer 2 formed on a base material sheet 1, a ventilation membrane 3 formed on the first adhesive layer 2, a second adhesive layer 4 formed on the ventilation membrane 3, and the protective film 5 formed on the second adhesive layer 4, wherein each of the first adhesive layer 2 and second adhesive layer 4 has an opening, and a cut line 7 is formed on the protective film 5 from an outer peripheral part thereof to a position corresponding to the opening of the second adhesive layer 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a ventilation filter provided with a ventilation film used in an electronic device that requires waterproofness and dustproofness, for example, an electronic device having an acoustic function, a method for fixing the ventilation filter, and a method for manufacturing an electric device.

  There is no sound in the housing of electronic devices such as mobile phones, small radios, transceivers, portable music players, laptop computers, headphones, earphones, outdoor microphones, digital cameras, etc. equipped with electroacoustic transducers such as speakers, microphones, and receivers. Through holes are provided from the inside of the housing to the outside and from the outside to the inside. A waterproof filter (breathable membrane) for the purpose of preventing water from entering the electronic device is attached to the sound hole. In addition, for example, an optical sensor is attached with a gas permeable membrane mainly intended to eliminate dust and internal / external pressure differences.

  The method for attaching the gas permeable membrane to the housing is as follows. First, a member in which a base sheet, an adhesive material A (for example, a double-sided adhesive tape), a gas permeable membrane, an adhesive material B, and a protective film (peeling sheet) are sequentially laminated is prepared. Next, the laminate (adhesive material A / breathable membrane / adhesive material B / protective film) other than the base material sheet is peeled off from the base material sheet. And a laminated body is affixed on the said sound transmission hole part by making the adhesive material A side into the housing | casing side. Finally, the protective film is peeled off by picking up the end of the protective film.

  In general, a method of providing a tab on the protective film in order to make it easy to pick the protective film on the adhesive material is known. For example, there is a method (Patent Document 1) in which a portion obtained by extending a part of the protective film from the end of the gas permeable membrane is used as a tab, or a method in which a material other than the protective film is attached as a tab (Patent Document 2) .

Japanese Patent Laying-Open No. 2004-10854 (FIG. 3) Japanese Patent Laying-Open No. 2005-15631 (FIG. 2)

  One problem in the technique of picking and peeling off a part of the protective film is that not only the protective film but also the adhesive material A is peeled off from the casing which is the adherend when picking up the protective film. Although peeling can be prevented by lowering the adhesive strength between the adhesive material B and the protective film as compared with the adhesive strength between the adhesive material A and the adherend, the selection range of the material is narrowed. When a porous polytetrafluoroethylene film (hereinafter referred to as “porous PTFE membrane”) is used as the gas permeable membrane, since the porous PTFE membrane is stretched in the horizontal direction of the membrane, the vertical direction of the membrane When the protective film is peeled off, the gas permeable membrane itself may tear in the direction perpendicular to the membrane.

  By the way, an opening is formed in the adhesive material B studied by the present inventor, and a region bonded to the protective film has a frame shape surrounding the periphery of the opening. This is to prevent airflow from being hindered by the adhesive material. Accordingly, an object of the present invention is to provide a shape suitable for preventing peeling of the adhesive material A when the protective film is picked up in a ventilation filter in which the adhesive material B has a frame shape.

  In order to solve the above-mentioned problems, the present inventor prototyped protective films of various shapes and repeated the peeling test to form a cut from the outer periphery of the protective film to the position corresponding to the opening of the adhesive material B. As a result, the protective film is peeled in order along the periphery of the opening of the adhesive material B starting from this cut, and it is determined that the peeling of the adhesive material A is prevented without applying a large force above the adhesive material A. The present invention has been completed.

The ventilation filter of the present invention that can achieve the above object is:
A first adhesive layer formed on the base sheet, a gas permeable film formed on the first adhesive layer, a second adhesive layer formed on the gas permeable film, and the second adhesive A ventilation filter having a protective film formed on the layer, wherein each of the first adhesive layer and the second adhesive layer has an opening, and the protective film has an opening from an outer periphery of the protective film. A notch reaching the position corresponding to the opening of the second adhesive layer is formed.

  In the ventilation filter, it is preferable that the outer peripheral portion of the protective film has a knob portion that is not bonded to the second adhesive layer.

  In the above ventilation filter, the protective film has an opening communicating with the opening of the second adhesive layer, and the cut line is configured to extend from the outer peripheral portion of the protective film to the opening of the protective film. Is desirable.

  In the ventilation filter, it is desirable that a predetermined mark is attached to the knob.

  In the ventilation filter, it is desirable that the protective film is colored with a chromatic color.

  In the ventilation filter, it is preferable that the base sheet has an opening communicating with the opening of the first adhesive layer.

  In the ventilation filter, it is preferable that the ventilation film is a fluororesin film.

  In the ventilation filter, it is desirable that the ventilation membrane is a porous polytetrafluoroethylene membrane.

  In the ventilation filter, it is desirable that a liquid repellent is added to the surface of the ventilation film.

  In the ventilation filter, the adhesive layer is preferably a double-sided pressure-sensitive adhesive tape.

The method for fixing the ventilation filter of the present invention that can achieve the above-mentioned object is as follows.
A first adhesive layer having an opening, a gas permeable membrane, a second adhesive layer having an opening, and a protective film are sequentially laminated on the base sheet, and the protective film is an outer peripheral portion of the protective film. A first step of forming a ventilation filter having a cut from the first adhesive layer to a position corresponding to the opening of the second adhesive layer, a second step of peeling the base sheet from the ventilation filter, and attaching the ventilation filter A third step of attaching to the body and a fourth step of removing the protective film by pinching one side portion of the outer peripheral portion of the protective film divided into two across the cut.

  In the above method, it is preferable that the one side portion opposite to the one side portion is picked and the base sheet is peeled off.

The method of manufacturing the electrical device of the present invention that can achieve the above-described object is as follows.
A first adhesive layer having an opening, a gas permeable membrane, a second adhesive layer having an opening, and a protective film are sequentially laminated on the base sheet, and the protective film is an outer peripheral portion of the protective film. A first step of forming a ventilation filter having a cut from the first adhesive layer to a position corresponding to the opening of the second adhesive layer, a second step of peeling the base sheet from the ventilation filter, and housing the ventilation filter And a fourth step of removing the protective film by picking one side of the outer peripheral portion of the protective film divided into two across the cut.

  In the present invention, since a cut is formed from the outer peripheral portion of the protective film to the position corresponding to the opening of the second adhesive layer, the protective film starts from the cut along the periphery of the opening of the second adhesive layer. It peels off in order. Therefore, a large force is not applied to the first adhesive layer, and peeling of the first adhesive layer is prevented.

It is a bird's-eye view of the ventilation filter in Embodiment 1 of this invention. It is a bird's-eye view which shows the state with which the ventilation filter in Embodiment 1 of this invention was mounted | worn with the housing | casing. (A)-(c) is a bird's-eye view which shows a mode that the protective film of the ventilation | gas_flowing filter in Embodiment 1 of this invention is peeled in order. (D)-(f) is a bird's-eye view which shows a mode that the protective film of a ventilation filter is peeled in order following FIG. (A) is a top view of the ventilation filter in Embodiment 2 of this invention, (b) is a top view of the other ventilation filter in Embodiment 2 of this invention. (A), (b) is a top view of the other ventilation filter in Embodiment 2 of this invention. It is a top view of the other ventilation filter in Embodiment 2 of this invention. It is a top view of the other ventilation filter in Embodiment 2 of this invention. FIG. 3 is a cross-sectional view of the ventilation filter in the first embodiment. 6 is a cross-sectional view of a ventilation filter according to Embodiment 3. FIG. It is a top view of the ventilation filter in Embodiment 4 of this invention. It is a top view of the other ventilation filter in Embodiment 4 of this invention. It is a top view of the ventilation filter in Embodiment 5 of this invention. (A), (b) is a top view of the other ventilation filter in Embodiment 5 of this invention. It is sectional drawing of the ventilation filter in Embodiment 6 of this invention. It is sectional drawing of the other ventilation filter in Embodiment 6 of this invention. It is sectional drawing of the other ventilation filter in Embodiment 6 of this invention. It is sectional drawing of the ventilation filter in Embodiment 7 of this invention. It is sectional drawing of the ventilation filter in Embodiment 8 of this invention. It is sectional drawing of the other ventilation filter in Embodiment 8 of this invention. It is sectional drawing of the other ventilation filter in Embodiment 8 of this invention. It is sectional drawing of the other ventilation filter in Embodiment 8 of this invention.

1. Structure of Ventilation Filter Hereinafter, the structure of the ventilation filter in the embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
1. Outline of Structure of Ventilation Filter FIG. 1 is a bird's-eye view of a ventilation filter according to Embodiment 1 of the present invention. In FIG. 1, a first adhesive layer 2, a gas permeable membrane 3, a second adhesive layer 4, and a protective film 5 are sequentially laminated on a base sheet 1 to constitute a gas permeable filter. The first adhesive layer 2 and the second adhesive layer 4 have openings 2a and 4a, respectively (see FIGS. 19 to 22 which are sectional views). A cut 7 is formed in the protective film 5 from the outer peripheral portion of the protective film 5 to a position corresponding to the opening 4 a of the second adhesive layer 4.

2. Method for Fixing Ventilation Filter and Method for Manufacturing Electric Device A method for fixing the ventilation filter configured as described above to an adherend will be described. First, a laminate other than the base sheet 1 (first adhesive layer 2 / ventilation film 3 / second adhesive layer 4 / protective film 5) is peeled off from the base sheet 1. Then, as shown in FIG. 2, the laminate is attached (attached) with the first adhesive layer 2 side set to the housing 6 side which is an adherend.

  Next, the process of peeling off the protective film 5 from the second adhesive layer 4 will be described. (A)-(c) of FIG. 3 is a bird's-eye view which shows a mode that the protective film of the ventilation filter in this Embodiment 1 is peeled in order. As shown in FIG. 3 (a), it is the outer peripheral portion of the protective film 5 and is divided into two parts by a cut 7 (hereinafter, this one side part is referred to as a “pick part 8” (FIG. 5). The other side is described as “Tab 9 (see FIG. 5).” Hereinafter, except for the mode of FIG. 6B, the same is applied) and the protective film 5 is pulled upward. . FIG. 3 shows an example using tweezers. Of course, “pick” or “pull up” is a process that can be automated. After the cut 7 is separated as shown in FIG. 3 (b), the protective film 5 is formed along the periphery of the second adhesive layer 4 as shown in FIGS. 3 (c), 4 (d), and (e). Are peeled off sequentially. If the protective film 5 reaches the state shown in FIG. 4E, an elastic force is exerted to return the protective film 5 to its original planar shape. Therefore, even if the tweezers are not lifted further, the protective film 5 is the second adhesive layer. Easily (semi-automatically) leave 4 That is, the pulling length by tweezers can be short. Therefore, when this process is automated, the working distance (driving range) of a control arm (not shown) used instead of tweezers can be shortened. For this reason, this invention is useful also for size reduction of the peeling apparatus (not shown) containing a control arm. In FIGS. 4D and 4E, tweezers are not shown in order to avoid complication of the drawing.

  In the above description, one side portion of the outer peripheral portion of the protective film 5 that is a portion where the back surface of the protective film 5 and the second adhesive layer 4 are not bonded and is divided into two by the cut 7. Although the example which picks up the knob | pick part 8 is called upward was demonstrated, what makes the essential condition of this invention that the part which the protective film 5 has not adhere | attached on the 2nd contact bonding layer 4 exists exists is not. Even if the entire back surface of the protective film 5 is adhered to the second adhesive layer 4, if a part of the protective film 5 is picked up, the protective film 5 is sequentially peeled along the periphery of the second adhesive layer 4. effective. For example, as shown in FIG. 10 to be described later, it is possible to pick up even a portion where the protective film 5 is bonded to the second adhesive layer 4.

  As described above, the first adhesive layer 2 is prevented from being peeled off by forming the cut line 7 from the outer peripheral portion of the protective film 5 to the position corresponding to the opening of the second adhesive layer 4 in the protective film 5. Thus, a very effective method for fixing the ventilation filter is realized, and when the adherend is the casing 6 constituting the electronic device, an effective method for manufacturing an electric device is realized.

3. Detailed Description of Individual Components Hereinafter, the base sheet 1, the first adhesive layer 2, the gas permeable membrane 3, the second adhesive layer 4, and the protective film 5 constituting the ventilation filter will be described in detail.

(1) Substrate sheet The substrate sheet 1 in the present embodiment plays a role of storing and transporting the thin air-permeable membrane 3, and there is no particular limitation on the material or the like as long as it is a sheet-like member. As the base material of the base material sheet 1, it is preferable to use a PET (polyethylene terephthalate) film having at least one surface or both surfaces treated with a silicone-based release agent. Examples of materials other than PET include polyesters such as polybutylene terephthalate, polyolefins such as polypropylene, polyethylene, and polymethylpentene, resin films such as polycarbonate, glassine paper, fine paper, coated paper, impregnated paper, and synthetic paper. And metal foils such as paper, aluminum, and stainless steel.

  The thickness of the base sheet 1 is, for example, 10 to 150 μm, preferably 50 to 125 μm. The surface of the substrate may be subjected to corona discharge treatment, plasma treatment, flame plasma treatment or the like, or a primer layer may be provided in order to improve the adhesion to the release agent or the pressure-sensitive adhesive. As the primer layer, a polymer material (so-called anchor coat agent) such as polyethylene, polypropylene, styrene copolymer, polyester, polyurethane, polyvinyl alcohol, polyethyleneimine, polyacrylate, polymethacrylate, and modified products thereof is used. I can do it.

(2) First and second adhesive layers The first and second adhesive layers 2 and 4 have openings 2a and 4a. The shape of the opening is not particularly limited, and may be circular, elliptical, rectangular, or polygonal. As a method of forming the first and second adhesive layers 2 and 4 having the opening pattern, for example, a method by screen printing or a method of transferring an adhesive melt to the base sheet 1 with a gravure pattern roll is available. is there.

  As described above, the first and second adhesive layers 2 and 4 may be formed by layering the adhesive itself, but a double-sided pressure-sensitive adhesive tape can also be used. Double-sided adhesive tapes include nonwoven nonwoven fabric double-sided adhesive tapes made of polyethylene nonwoven fabric, polypropylene nonwoven fabric, nylon nonwoven fabric, etc., PET-based double-sided adhesive tape, polyimide-based double-sided adhesive tape, nylon-based double-sided adhesive tape, foam (For example, urethane foam, silicone foam, acrylic foam, polyethylene foam) Various types of substrates such as a base double-sided pressure-sensitive adhesive tape and a base material-less double-sided pressure-sensitive adhesive tape can be used.

  In addition to the adoption of the basic configuration of the present invention in which the protective film 5 is provided with the cuts 7, the adhesion between the second adhesive layer 4 and the protective film is compared with the adhesive strength between the first adhesive layer 2 and the adherend. Lowering the strength is also a preferred form. In addition, even if the adhesive strength of the second adhesive layer 4 and the protective film is higher than the adhesive strength of the first adhesive layer 2 and the adherend, it is protected by adjusting the formation position and length of the cuts 7. Since the peeling work of only the film 5 is possible, the selectable range of materials is expanded.

  In addition, in this invention, an adhesive agent refers to the substance generally used for bonding a thing and a thing, and shall include what is called an adhesive.

(3) Air-permeable membrane As the constituent material of the air-permeable membrane 3, polyethylene, polypropylene, polystyrene, polyimide, etc. can be used, preferably a fluororesin excellent in waterproofness, more preferably a porous PTFE film. Recommended to use. As the microscopic shape of the gas permeable membrane 3, a net shape, a mesh shape, or a porous shape can be used. The porous PTFE membrane is excellent in drip-proofing properties and is suitable for applications in which the inside and outside of an electric device have air permeability while preventing entry of water droplets, oil droplets, and dust.

  However, porous PTFE generally has a lower surface energy than that of general-purpose polymer polypropylene (PP) or polyethylene (PE), and the binding between fine molecular chains in the material is weak. Therefore, porous PTFE has a lower strength than other porous polymer membranes. In particular, a porous PTFE membrane used for waterproofing of acoustic equipment is configured to be thin in order to improve acoustic characteristics, and therefore the strength in the thickness direction is very low. Therefore, when a porous PTFE membrane is used as the constituent material of the gas permeable membrane 3, if the present invention is applied, the tensile force in the direction perpendicular to the membrane when the protective film 5 is peeled is reduced. It is extremely effective for prevention.

  Next, a method for producing a porous PTFE membrane will be described. A porous PTFE membrane is obtained by removing a molding aid from a molded body of a paste obtained by mixing PTFE fine powder with a molding aid, stretching at a high temperature and a high speed, and further firing if necessary. It is obtained. In the case of uniaxial stretching, the nodes (folded crystals) are in the form of thin islands perpendicular to the stretching direction, and the fibrils (straight-lined drawn by unfolding the folded crystals by stretching to connect the nodes) Molecular bundle) is oriented in the stretching direction. And it has a fibrous structure in which spaces defined between fibrils or between fibrils and nodes become holes. In the case of biaxial stretching, the fibrils spread radially, the nodes connecting the fibrils are scattered in islands, and a cobweb-like fibrous structure in which many spaces defined by the fibrils and the nodes exist. ing.

  The gas permeable membrane 3 may be a uniaxially stretched porous PTFE membrane or a biaxially stretched porous PTFE membrane.

  The gas permeable membrane 3 is preferably strong enough to be used alone (single layer), but may be used by being laminated with a stretchable breathable reinforcing layer such as a nonwoven fabric, a net such as a woven fabric or a knitted fabric. Good.

  As physical characteristics of the gas permeable membrane 3, it is desirable to have a water pressure resistance of 1 kPa or more, more preferably 10 kPa or more, and an air permeability (JIS P 8117) of 1000 seconds or less, more preferably 100 seconds or less.

  The gas permeable membrane 3 is preferably provided with liquid repellency on the inner surface of the pores. By imparting liquid repellency to the gas permeable membrane 3, various contaminants such as body fat, machine oil, and water droplets can be prevented from penetrating or being retained in the pores of the gas permeable membrane 3. These contaminants deteriorate the trapping characteristics and ventilation characteristics of the gas permeable membrane 3 and cause the function of the gas permeable membrane to be impaired.

  In the claims and the present specification, as a method for imparting liquid repellency, a liquid repellent material can be used, or a liquid repellent can be added. The term “liquid repellent” includes “water repellent”, “oil repellent”, “water repellent”, and the like. Hereinafter, the water- and oil-repellent polymer will be described as an example.

  As the water / oil repellent polymer, a polymer having a fluorine-containing side chain can be used. Details of the water- and oil-repellent polymer and the method of combining it with a porous PTFE membrane are disclosed in WO94 / 22928.

  In addition to the liquid repellent material described above, the air-permeable membrane 3 can be provided with various functions by adding a hydrophilic material, a conductive material, a coloring material, an antistatic material, an antibacterial material, and the like. it can.

(4) Protective film The protective film 5 protects the gas permeable membrane 3 during storage or transportation, and as the material, a paper-released product or a resin film is preferably used. The material of the resin film is not particularly limited, but polyolefin resins such as PE and PP; polyester resins such as PET; In addition, the resin film may be subjected to a release treatment such as coating the resin film surface with a silicone resin or the like. The thickness of the protective film is not particularly limited, but if it is too thin, the protective function is not achieved, so that the thickness is 10 μm or more, preferably 50 μm or more. Further, as described above, the protective film 5 can be easily peeled off simply by pulling the protective film 5 slightly upward as described above by giving the protective film 5 an appropriate elastic force. In the case of using a resin, it is desirable that the thickness of the protective film 5 is 10 μm or more, preferably 50 μm or more. On the other hand, if the protective film 5 is too thick, the rigidity of the protective film 5 is increased, and the workability of the protective film 5 is deteriorated or the protective film 5 is difficult to peel off. Therefore, the protective film 5 is 150 μm or less, preferably 125 μm or less. It is desirable.

  In the first embodiment, it is desirable that the knob 8 is configured not to be bonded to the second adhesive layer 4. For example, the outer shape of the protective film 5 may be formed so as to extend from the outer shape of the second adhesive layer 4, and conversely, the outer shape of the second adhesive layer 4 may be recessed from the outer shape of the protective film 5. You may form in. Thereby, the work which picks up and peels off protective film 5 becomes efficient.

  In the first embodiment, the outer peripheral portion of the protective film 5 is provided with the knob 8 on one side with a notch 7 interposed therebetween, and the tab not bonded to the second adhesive layer 4 on the other side. 9 may be provided. When the ventilation filter in the state of FIG. 1 is attached to the housing 6 as shown in FIG. 2, if the ventilation filter is handled by grasping the tab 9, the work is performed without directly touching the thin and easily damaged ventilation membrane 3. It can be performed.

  As shown in FIG. 5A, the protective film 5 is used for positioning for peeling off the ventilation filter from the base sheet 1 during conveyance, or for positioning when attaching the ventilation filter to the adherend. The tab 9 may be provided with a circular hole or an oval hole as shown in FIG. In addition, the hole may be a rectangle (not shown) such as a rectangle or a square, or a plurality of holes may be provided in one tab 9.

(Embodiment 2)
Hereinafter, the ventilation filter concerning Embodiment 2 of the present invention is explained. FIGS. 5-8 shows the top view of the ventilation filter concerning Embodiment 2 of this invention, and shows various variations of the label | marker attached | subjected to the protective film 5. FIGS.

  A transparent material is often used for the protective film 5 of the ventilation filter of the present invention. For this reason, when the protective film 5 is peeled off, it may be difficult to recognize the place (the knob portion 8) where the protective film 5 should be picked. Therefore, in this embodiment, an example in which a protective film 5 (particularly the knob 8) is provided with an optically recognizable marker (for example, a character, a symbol, a pattern, or a color) to facilitate recognition of a place to be picked. explain. Note that “optically recognizable” includes not only visual discrimination but also detection by a CCD or other optical sensor, and includes recognition by infrared rays or ultraviolet rays as well as visible rays.

  In FIGS. 5A and 5B, a recognizable circular mark 10 is attached to the knob 8.

  In FIG. 6A, the knob 8 is provided with a number 10b (a character “2” in a circle). On the other hand, the tab 10 is provided with a number 10a (a circled letter “1”) 10a because the tab 9 to be grasped when the ventilation filter is mounted on the housing 6 as shown in FIG. This is to make it easy to distinguish the knob 8 from which the protective film 5 is to be picked.

  On the other hand, as shown in FIG. 6B, the marker 10b can be arranged on the opposite side of the cut 7 from the example of FIG. 6A, that is, on the same side as the marker 10a. In this case, the part to which the mark 10b is attached is the picking part 8, and the effect of the present invention can be achieved by picking up the picking part 8. Note that the tab 9 is gripped when the ventilation filter is mounted on the housing 6, but the gripping position (the mark 10a) should be as far as possible from the cut 7 as shown in FIGS. 6 (a) and 6 (b). desirable. This is because if the tab 9 is gripped at a position close to the cut line 7, only the protective film 5 may be peeled along the cut line 7.

  In FIG. 7, a partial range of the knob portion 8 is colored to be a marker 10. Although not shown, the entire protective film 5 may be colored in order to prevent forgetting of the peeling operation due to oversight of the protective film 5. In this case, the range of the knob 8 is preferably colored in a different color.

  In FIG. 8, an arrow-shaped marker 10 indicating the position of the cut 7 is attached to a part of the tab 9. This arrow may be attached to the knob 8.

(Embodiment 3)
The ventilation filter according to Embodiment 3 of the present invention will be described below.

  9 is a cross-sectional view of the ventilation filter according to the first embodiment shown in FIG. 1, and FIG. 10 is a cross-sectional view of the ventilation filter according to the third embodiment. In the ventilation filter according to the first embodiment, the knob 8 is formed by extending the end of the protective film 5 outward from the end of the second adhesive layer 4. As shown in FIG. 10, an extension member 5 b different from the protective film 5 may be provided to form the knob 8.

(Embodiment 4)
The ventilation filter according to Embodiment 4 of the present invention will be described below. FIG.11 and FIG.12 is a top view of the ventilation filter concerning Embodiment 4 of this invention, and shows the variation of the form of the cut 7 of the protective film 5. FIG. In Embodiment 1, although the example which formed the notch 7 in the part extended widely in the protective film 5 was demonstrated, the formation position of the notch 7 is not restricted to this, and as shown in FIG. Any location is acceptable. Moreover, as shown in FIG. 12, the cut 7 may be formed in a curved shape.

  When the cut line 7 is formed by a straight line, the angle is not particularly limited. For example, as shown in FIG. 11, the intrusion angle α of the cut 7 with respect to the outer peripheral line of the second adhesive layer 4 (the angle formed on the same side as the knob 8 with respect to the cut 7) may be any number. In order to prevent the first adhesive layer 2 and the casing 6 from being peeled off, the beginning of peeling of the protective film 5 is most important, and therefore an acute angle is preferable. Specifically, it is, for example, 10 degrees to 90 degrees, preferably 30 degrees to 60 degrees. When the penetration angle α is an obtuse angle (greater than 90 degrees), the angle β (= 180 degrees−α) corresponding to the complementary angle of α is an acute angle. In this case, the protective film 5 can be peeled off by changing the knob 8 to a position opposite to the cut 7 (that is, the same side as the angle β), starting from the acute angle β.

(Embodiment 5)
The ventilation filter according to Embodiment 5 of the present invention will be described below. 13 and 14 are plan views of the ventilation filter according to the fifth embodiment of the present invention. In Embodiment 1, the protective film 5 has an opening 5 a that communicates with the opening 4 a of the second adhesive layer 4, and the cut 7 extends from the outer periphery of the protective film 5 to the opening 5 a of the protective film 5. Although the example has been described, in the present embodiment, the opening 5a is not provided in the protective film 5 as shown in FIG. If the opening 5a as in the first embodiment is provided, the protective film 5 is peeled off more smoothly, but the ventilation filter according to the fifth embodiment is more advantageous from the viewpoint of protecting the ventilation film 3. is there.

  When the opening 5a is not provided in the protective film 5 as shown in FIG. 13, in order to make the protective film 5 peel off smoothly, the cut 7 is formed in the protective film 5 as shown in FIG. It is desirable to pass through the position corresponding to the opening 4 a of the adhesive layer 4 from the outer periphery of the adhesive layer 4 and reach the inside of the opening 4 a of the second adhesive layer 4. Furthermore, as shown in FIG. 14B, the cut 7 is desirably provided with an extension 7a extending in the longitudinal direction of the opening 4a. This is because the protective film 5 is more easily peeled off along the outer periphery of the second adhesive layer 4 due to the presence of the extension 7a.

(Embodiment 6)
The ventilation filter according to Embodiment 6 of the present invention will be described below. 15-17 is sectional drawing of the ventilation filter concerning Embodiment 6 of this invention. These show various variations of the laminated structure of the ventilation filter.

  As described in the first embodiment, the first adhesive layer 2 may be composed of a single pressure-sensitive adhesive layer (for example, an acrylic pressure-sensitive adhesive), but as shown in FIG. It can be composed of a double-sided adhesive tape having a three-layer structure of 2b / tape substrate 2c / adhesive layer 2b. Of course, the 2nd contact bonding layer 4 can also be comprised with a double-sided adhesive tape. The material example of the double-sided pressure-sensitive adhesive tape is as described in the first embodiment.

  In addition, as shown in FIG. 16, the second adhesive layer 4 / spacer 12 (for example, PET, sponge material) / second made of double-sided adhesive tape is provided between the gas permeable membrane 3 and the protective film 5. A laminated structure of the adhesive layer 4 may be used. By interposing the spacer 12 further, it is possible to optimally adjust the distance between the gas permeable membrane 3 and the vibration membrane in the electroacoustic transducer.

  In addition, as shown in FIG. 17, it is good also as the 2nd contact bonding layer 4 / spacer 12 / adhesion layer 4b comprised by a double-sided adhesive tape in an order from the bottom between the ventilation film 3 and the protective film 5. FIG.

(Embodiment 7)
The ventilation filter according to Embodiment 7 of the present invention will be described below. FIG. 18 is a cross-sectional view of a ventilation filter according to Embodiment 7 of the present invention. As described in the first embodiment, it is preferable that the gas permeable membrane 3 has sufficient strength to be used alone (single layer). However, as shown in FIG. 18, the reinforcing membrane 11 (for example, non-woven fabric, woven fabric, It may be used by laminating with a net such as a knitted fabric). The stacking order of the reinforcing film 11 and the gas permeable film 3 is not particularly limited, and the reinforcing film 11 may be on the upper side of the gas permeable film 3 contrary to the order shown in FIG. The reinforcing membrane 11 and the gas permeable membrane 3 do not necessarily need to be in close contact with each other, and a double-sided adhesive tape (not shown) may be sandwiched between them. When a double-sided pressure-sensitive adhesive tape is sandwiched between the reinforcing film 11 and the gas permeable membrane 3, it is advantageous in that the deterioration of acoustic characteristics is less than that in which the reinforcing film 11 and the gas permeable membrane 3 are in close contact with each other.

(Embodiment 8)
Hereinafter, a ventilation filter according to Embodiment 8 of the present invention will be described.
19-22 is sectional drawing of the ventilation filter concerning Embodiment 8 of this invention. As shown in FIGS. 20 and 22, the base sheet 1 may be formed with an opening 1 a communicating with the opening 2 a of the first adhesive layer 2.

  As shown in FIGS. 19 and 20, the protective film 5 may have an opening 5 a that communicates with the opening 4 a of the second adhesive layer 4. There are four combinations of these as shown in FIGS.

DESCRIPTION OF SYMBOLS 1 Base material sheet 1a Opening part 2 1st contact bonding layer 2a Opening part 2b Adhesive layer 2c Tape base material 3 Breathable film 4 2nd adhesive layer 4a Opening part 4b Adhesive layer 4c Double-sided adhesive tape base material 5 Protective film 5a Opening part 5b Extension member 6 Housing (adhered body)
7 Cut 7a Extension part 8 Knob part 9 Tab 10, 10a, 10b Mark 11 Reinforcement membrane 12 Spacer

Claims (13)

  A first adhesive layer formed on the base sheet, a gas permeable film formed on the first adhesive layer, a second adhesive layer formed on the gas permeable film, and the second adhesive A ventilation filter having a protective film formed on the layer, wherein each of the first adhesive layer and the second adhesive layer has an opening, and the protective film has an opening from an outer periphery of the protective film. A ventilation filter characterized in that a cut is formed to reach a position corresponding to the opening of the second adhesive layer.   2. The ventilation filter according to claim 1, wherein an outer peripheral portion of the protective film has a knob portion that is not bonded to the second adhesive layer.   The said protective film has an opening part connected to the opening part of a said 2nd contact bonding layer, The said cut | interruption reaches from the outer peripheral part of the said protective film to the opening part of this protective film. Ventilation filter.   The ventilation filter according to claim 2 or 3, wherein the knob is provided with a predetermined mark.   The ventilation filter according to any one of claims 1 to 4, wherein the protective film is colored with a chromatic color.   The ventilation filter according to claim 1, wherein the base sheet has an opening communicating with the opening of the first adhesive layer.   The ventilation filter according to claim 1, wherein the ventilation film is a fluororesin film.   The ventilation filter according to claim 1, wherein the ventilation film is a porous polytetrafluoroethylene film.   The ventilation filter according to any one of claims 1 to 8, wherein a liquid repellent is added to a surface of the ventilation film.   The ventilation filter according to any one of claims 1 to 9, wherein the adhesive layer is a double-sided pressure-sensitive adhesive tape.   A first adhesive layer having an opening, a gas permeable membrane, a second adhesive layer having an opening, and a protective film are sequentially laminated on the base sheet, and the protective film is an outer peripheral portion of the protective film. A first step of forming a ventilation filter having a cut from the first adhesive layer to a position corresponding to the opening of the second adhesive layer, a second step of peeling the base sheet from the ventilation filter, and attaching the ventilation filter A method for fixing a ventilation filter, comprising: a third step of attaching to a body; and a fourth step of removing one of the outer peripheral portions of the protective film divided into two across the cut and peeling off the protective film. .   The ventilation filter fixing method according to claim 11, wherein the base sheet is peeled off by gripping the other one side opposite to the one side.   A first adhesive layer having an opening, a gas permeable membrane, a second adhesive layer having an opening, and a protective film are sequentially laminated on the base sheet, and the protective film is an outer peripheral portion of the protective film. A first step of forming a ventilation filter having a cut from the first adhesive layer to a position corresponding to the opening of the second adhesive layer, a second step of peeling the base sheet from the ventilation filter, and housing the ventilation filter A method for manufacturing an electric device, comprising: a third step of attaching to the outer periphery of the protective film; and a fourth step of removing the protective film by gripping one side portion of the outer peripheral portion of the protective film divided into two across the cut.