JP2000195368A - Membrane switch and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a membrane switch and its manufacturing method enabling improvements in reliability of electric continuity as the switch. SOLUTION: In this membrane switch, the surface of an upper film 5a is formed with plural electrodes and upper wiring 9a connecting between the electrodes, while the upper wiring 9a is gathered in a wiring connection part 13 formed in the upper film 5a. The surface of a lower film 5b is formed with plural electrodes, lower wiring connecting between the electrodes, and upper wiring connection wiring 9c connected to external terminals. A spacer 6 is interposed between the upper film 5a and the lower film 5b, while the upper wiring 9a and the upper wiring connection wiring 9c are glued, fixed and electrically connected through an anisotropic conductive film 2. The wiring connection part 13 is formed in advance in a partially projecting shape toward the upper wiring connection wiring 9c by drawing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane switch incorporated in a keyboard or the like of a personal computer and a method of manufacturing the same, and more particularly, to a membrane switch capable of improving the reliability of electrical conduction and a method of manufacturing the same.

[0002]

2. Description of the Related Art FIG. 4 is a schematic view showing a part of a keyboard used as an input device of a conventional personal computer. FIG. 5A is a perspective view showing a key top portion of the keyboard, FIG. 5B is a perspective view showing a membrane switch, and FIG. 5C is a perspective view showing a support plate. FIG. 6 is a plan view showing a lower electrode sheet of the membrane switch shown in FIG. 5B.

As shown in FIGS. 4 and 5 (b) and 5 (c), a support plate 28 made of a metal plate such as Fe and Al is used.
A membrane switch 31 is disposed on the top. FIG.
As shown in FIG. 6, a plurality of electrodes 27a made of Ag and an upper wiring (not shown) connecting the electrodes 27a are provided at predetermined positions on the surface of the upper film 25a made of polyethylene terephthalate (PET). The upper electrode sheet is formed by printing. These upper wirings are integrated in a wiring connection portion provided in the upper film 25a, and the upper film 25a is provided with a U-shaped slit for dividing the wiring connection portion.

Similarly, a lower film 25 made of PET is used.
a plurality of electrodes 27b made of Ag and a lower wiring 2 connecting these electrodes 27b at predetermined positions on the surface of
9b and upper wiring connection wiring 29c connected to an external terminal (not shown) provided on the tail portion 31a are formed by printing to form an upper electrode sheet. The lower wiring 29b and the upper wiring connecting wiring 29c are integrated in the tail 31a. And the electrodes 27a,
An upper electrode sheet and a lower electrode sheet are arranged so that the surfaces on which the electrodes 27b are formed face each other, and a spacer 2 made of PET having an opening at a position matching the electrodes is provided between the two.
6 are stacked.

After the upper electrode sheet, the spacer and the lower electrode sheet are strictly aligned using a jig or the like, a fusion horn (not shown) is formed in a region where electrodes, wirings and the like are not formed. ) Are brought into contact with each other, and the ultrasonic wave oscillated from the distal end of the fusion horn is used to weld the fusion portion 31b.
Are formed and these are adhered. This fused part 3
1b is usually formed at two places and has a circular shape of about 2.0 to 3.5 mm.

On the upper film 25a, a plastic base 24 constituting the key top portion 32 is disposed. The base 24 includes a portion where a key is formed,
That is, an opening is provided at a position matching the electrodes 27a and 27b when the key top portion 32 is arranged on the membrane switch 31, and a rubber cushion 23 is provided in the opening. The rubber cushion 23 includes a main body 23 having a projection 23c for pressing the switch.
a and a leg 23b supporting the main body 23a, whereby the main body 23a is supported in a state of being separated from the upper surface of the upper film 25a.

Further, above the rubber cushion 23,
A plastic finger contact part 21 supported by a support 22 is arranged. The support tool 22 supports the finger touch section 21 in a state where two rod-shaped members locked to each other at the center cross each other. The end of the support 22 is locked so as to slide on the back surface side of the finger touch portion 21 and the upper surface side of the base body 24. When the finger touch portion 21 is not pressed, the finger touch portion 21 is not pressed.
Is supported by the main body 23a of the rubber cushion 23,
Being lifted. As described above, the key top portion 32 is configured by the base 24, the rubber cushion 23, the support 22, and the finger touching portion 21.

Here, the method of assembling the keyboard shown in FIGS. 4 and 5 will be described in detail below. FIG. 7 (a)
FIG. 7B is a cross-sectional view illustrating a method of assembling the keyboard in the order of steps. However, FIGS. 7A and 7B show the upper wiring connection wiring 2 of the lower electrode sheet shown in part A of FIG.
9c shows a method of connecting the wiring of the upper electrode sheet with the wiring 9c. Before assembling the keyboard, the upper wiring 29a integrated in the wiring connection part 33 of the upper electrode sheet and the upper wiring connection wiring 29c formed on the lower film 25b are not connected. Then, by assembling the keyboard, the wiring connection part 33 is pressed downward, and the upper wiring 29a and the upper wiring connecting wiring 29c are connected.

That is, as shown in FIG. 7A, a groove 24a which is concave upward is formed on the back surface side of the base 24 of the key top portion 32 at a position matching the wiring connection portion 33. . Therefore, in the keyboard assembling process, first, the rubber press-contact tube 34 is inserted into the groove 24a, and then the base 24 is brought into contact with the upper surface of the upper film 25a.

At this time, as shown in FIG. 7B, the slit 33a is provided in the upper film 25a so as to surround the wiring connection portion 33, so that the wiring connection portion 33 is pressed by the pressure welding tube 34. Distorted downward, upper wiring 29
a is pressed against the upper wiring connection wiring 29c of the lower electrode sheet. As a result, the upper wiring 29a and the upper wiring connecting wiring 29c are electrically connected, and current can flow to the electrode 27a of the upper electrode sheet via the upper wiring connecting wiring 29c. Circuit is completed.

In the keyboard constructed as described above, when a finger presses the finger touching portion 21 at a predetermined position, the rod-like members constituting the support 22 overlap linearly, and at the same time, the legs of the rubber cushion 23 The portion 23b is bent, and the main body 23a is pressed downward. Then, the protrusion 23c of the rubber cushion 23 presses the switch portion of the membrane switch 31, and the electrode 27a and the electrode 27b come into contact. As a result, a current flows between the wiring formed on the upper film 25a and the wiring 29b formed on the lower film 25b, and this information is transmitted to hardware (not shown) of the personal computer. Thereafter, when the finger touch portion 21 is released, the leg portion 23 b of the rubber cushion 23 is opened.
Returns to its original shape, the finger touching portion 21 is lifted, and the electrode 27a and the electrode 27b are separated.

Incidentally, even when the membrane switch 31 is incorporated in a housing other than the keyboard, the base 2
4 is provided in the housing, and the upper wiring 29a and the upper wiring connecting wiring are formed by the press-connecting tube in the same manner as shown in FIGS. 7A and 7B. 29c.

By the way, conventionally, a spacer is interposed between an upper film on which electrodes and wires are formed and a lower film, respectively, without forming upper wiring connecting wires and the like on the lower film. Membrane switches are also used. However, a membrane switch in which the upper film, the spacer, and the lower film are simply assembled has a total of two tails (male connectors) in the upper film and the lower film. Therefore, when this membrane switch is connected to a power supply and other wiring, it is necessary to insert the two connectors into separate female connectors.

Thus, as shown in FIGS. 7A and 7B, the upper wiring 29a is connected to the upper wiring connecting wiring 29c on the lower film, and the upper wiring 29a is handled on the lower film 25b. This allows the tail part of the membrane switch to be only on the lower film side,
Connection with other wiring is facilitated.

However, the above-described membrane switch 31 has the following problems. That is, FIG.
As shown in the figure, the upper wiring 29a and the upper wiring connecting wiring 2
9c, a groove 24 for inserting the press-contact tube 34 into the housing (the base 24 of the key top portion 32).
a is required. Therefore, the thickness of the housing is increased by the depth h _R of the groove 24a.

Further, since the press-connecting tube 34 is made of rubber, the raw material cost is high, and the cost for assembling the press-connecting tube 34 into the housing is high, so that the manufacturing cost of the entire membrane switch is reduced. There is also the problem of rising.

Further, there is a case where the casing is assembled by forgetting to incorporate the press-connecting tube 34. Then, the upper wiring 29a and the upper wiring connecting wiring 29c cannot be conducted, and the circuit of the membrane switch becomes an open circuit, so that the switching function cannot be obtained. Furthermore, even if the forgetting of the press-fitting tube 34 does not occur, the upper wiring 29a may not be formed due to a poor design of the tube 34 or a poor molding of the housing.
In some cases, the connection resistance of the contact portion between the wiring and the upper wiring connection wiring 29c may be increased, or the conduction between the two may be poor.

By the way, in order to solve the above-mentioned problem, the upper wiring 29a and the lower wiring 29a integrated in the wiring connection portion 33 of the upper electrode sheet using a conductive adhesive, for example, an anisotropic conductive film. There is a method of connecting the upper wiring connection wiring 29c of the electrode sheet.

The anisotropic conductive film is composed of a polymer as a main material, and is a connection material having three functions of an adhesive function, a conductive function and an insulating function. When the anisotropic conductive film is thermocompression-bonded, the anisotropic conductive film exhibits electrical anisotropy such that conductivity is obtained in the thickness direction and insulation is obtained in a direction parallel to the surface. FIG. 8 is a cross-sectional view showing a state in which the wiring of the upper electrode sheet and the wiring for connecting the upper wiring of the lower electrode sheet are connected by the anisotropic conductive film.

As shown in FIG. 8, the upper wiring 29a and the upper wiring connecting wiring 29c in the membrane switch configured as in the prior art are connected by the anisotropic conductive film 2. Since the anisotropic conductive film 2 has adhesive strength and conductivity, the upper wiring 29a and the upper wiring connecting wiring 29c can be adhesively fixed and electrically connected.

[0021]

However, in the case where the upper wiring 29a and the upper wiring connecting wiring 29c are connected by the anisotropic conductive film 2, as in the case of using the press-connecting tube, the wiring connecting portion is connected. Since the two wires are connected by distorting the wire 33 downward, a restoring force is applied to the wire connection portion of the upper electrode sheet to restore the original shape.
That is, a permanent stress is generated in a direction in which it is separated from the upper wiring connection wiring 29c. For this reason, any peeling force is applied to the wiring connection part 33 or the anisotropic conductive film 2
When the bonding strength of the two wirings is low, there is a possibility that the connection portion of both wirings is easily peeled off. For this reason, there is a problem that the electrical conduction reliability between the upper wiring 29a and the upper wiring connecting wiring 29c is low.

The present invention has been made in view of the above problems, and has as its object to provide a membrane switch capable of improving the reliability of electrical conduction as a switch and a method of manufacturing the same.

[0023]

According to the present invention, there is provided a membrane switch comprising: a first insulating film and a second insulating film disposed to face each other;
A plurality of first electrodes provided on a surface facing the insulating film; a first wiring connected to the plurality of first electrodes; a wiring connection portion on which the first wiring is integrated; A plurality of second electrodes provided on a surface of the film facing the first insulating film, and connection wiring connected to external terminals;
A second wiring connected to the plurality of second electrodes;
A spacer having a wiring connection opening at a position where the first wiring integrated with the wiring connection portion and the connection wiring are interposed between an insulating film and a second insulating film;
A conductive adhesive for adhering and fixing the first wiring and the connection wiring at the wiring connection part and electrically connecting the first wiring to the connection wiring, wherein the first insulating film is used for the connection at the wiring connection part. It is characterized by being molded so as to locally project toward the wiring.

[0024] A method of manufacturing a membrane switch according to the present invention is a method of manufacturing the membrane switch, wherein the first insulating film in the wiring connection portion is connected to the connection switch before the step of interposing the spacer. A step of molding so as to locally protrude toward the wiring, and a conductive adhesive for bonding and fixing both between the first wiring and the connection wiring at the wiring connection portion and electrically connecting the first wiring and the connection wiring. After the step of disposing and the step of interposing the spacer,
The first wiring and the connection wiring are bonded and fixed by pressing the wiring connection portion on which the first wiring is integrated and the second insulating film on which the connection wiring is formed via the conductive adhesive. And electrically conducting.

In this case, the external terminal is provided on a tail portion formed on the second insulating film, and the spacer has a switch opening at a position where the first electrode and the second electrode match. It may be configured.

Further, the projecting portion of the wiring connection portion may be formed by drawing with a press of a convex mold and a concave mold that match a predetermined projecting shape.

Further, the depth of the protruding portion of the wiring connection portion is (t _s +0.02 m) with respect to the thickness t _{s of the} spacer.
m) to the is (t _s + 0.04mm) preferred.

Further, it is preferable that the conductive adhesive is an anisotropic conductive adhesive.

In the present invention, since the first insulating film is formed so as to locally protrude toward the connection wiring at the wiring connection portion, the first insulating film is formed at the first connection portion at the wiring connection portion.
In the case where the wiring and the connection wiring are bonded and fixed via a conductive adhesive and are electrically connected, the permanent stress generated in the wiring connection portion in the direction of peeling off from the connection wiring is reduced. For this reason, the electrical conduction reliability as a switch can be improved.

Further, if the depth of the projecting portion of the wiring connection portion is (t _s +0.02 mm) to (t _s +0.04 mm) with respect to the thickness t _{s of the} spacer, the connection to the wiring connection portion is provided. Since the generation of permanent stress in the direction of peeling from the wiring can be prevented, the electrical conduction reliability of the switch can be further improved.

Further, it is preferable that the conductive adhesive is an anisotropic conductive adhesive, whereby the first insulating film is compared with the case where an isotropic conductive adhesive (not anisotropic) is used. It is easy to cure even at the wiring connection portion sandwiched between the wiring connection portion and the second insulating film, and when the circuit pitch of the wiring connection portion is narrow and the circuit is crushed at the time of bonding and fixing, the adhesive spreads between the circuits due to bleeding. Also has anisotropy,
Short circuits between circuits can be prevented.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a membrane switch according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. FIG. 1 is a sectional view showing a part of a membrane switch according to an embodiment of the present invention, and FIG. 2 is a sectional view showing a method of forming an upper electrode sheet. FIG.
(A) thru | or (c) are the schematic cross sections which similarly show the change of the peeling stress which arises in the wiring connection part of an upper electrode sheet.

As shown in FIG. 1, a plurality of electrodes made of Ag (first electrode: not shown) are provided at predetermined positions on the surface of an upper film (first insulating film) 5a made of polyethylene terephthalate (PET). An upper wiring (first wiring) 9a connecting the electrodes is formed by printing, thereby forming an upper electrode sheet. Note that these upper wirings 9a are integrated on a wiring connecting portion 13 provided on the upper electrode sheet, and the wiring connecting portion 13 is formed in advance by drawing to a shape locally projecting toward the lower electrode sheet. ing.

Similarly, at a predetermined position on the surface of the lower film (second insulating film) 5b made of PET,
A plurality of electrodes made of Ag (second electrode: not shown), lower wiring (second wiring: not shown) connecting these electrodes, and a tail portion for connecting a connector or the like to the membrane switch. The upper wiring connection wiring 9c connected to the external terminals (both not shown) is formed by printing, thereby forming a lower electrode sheet. The lower wiring 9b and the upper wiring 9
c is integrated in the tail.

Further, an upper electrode sheet and a lower electrode sheet are arranged so that the surfaces on which the electrodes are formed face each other, and a spacer 6 made of PET is interposed therebetween. The spacer 6 has a switch opening (not shown) and a wiring connection opening 6a at a position where the upper electrode and the lower electrode match and a position where the wiring connection portion 13 is formed.
Therefore, the upper electrode and the lower electrode come into contact with each other via the switch opening provided in the spacer 6, and the upper electrode integrated with the wiring connection portion 13 via the wiring connection opening 6a. The wiring 9a is in contact with the upper wiring connecting wiring 9c formed on the lower film 5b.

The upper electrode sheet, the spacer 6 and the lower electrode sheet are strictly aligned by using a jig or the like, and then, in a region where the electrodes, wirings, etc. are not formed, a spacer bonding fusion by ultrasonic fusion. An attachment portion (not shown) is formed, and thereby the upper electrode sheet and the lower electrode sheet are joined to the spacer 6. Also,
The wiring connection portion 13 where the upper wiring 9a is formed and the region where the upper wiring connection wiring 9c is formed on the lower film 5b are connected to the anisotropic conductive film (anisotropic conductive adhesive) disposed therebetween. 2).

As described above, the upper wiring 9a and the upper wiring connecting wiring 9c are bonded and fixed via the anisotropic conductive film 2 and are electrically connected to each other to constitute the membrane switch 1. .

Next, a method for manufacturing the membrane switch will be described. First, a polyethylene terephthalate (PET) sheet constituting the upper film 5a, the lower film 5b, the spacer 6, and the like, and the anisotropic conductive film 2 and the like are prepared. Next, an upper electrode made of Ag and an upper wiring 9a are formed by printing on the surface of the area to be the upper film 5a of the PET sheet, and a lower electrode made of Ag and the lower wiring are formed on the surface of the area to be the lower film 5b. Then, the wiring 9c for connecting the upper wiring is formed by printing.

Next, the PET sheet is applied to the upper film 5.
a, cutting into the shape of the lower film 5b and the spacer 6; At this time, a switch opening and a wiring connection opening 6a are provided at predetermined positions of the spacer.

Next, as shown in FIG. 2, in order to draw the wiring connection portion 13 of the upper electrode sheet into a locally protruded shape toward the lower electrode sheet, a convex shape matching a predetermined protruding shape is formed. Mold press mold 16a and concave press mold 1
6b, the wiring connection portion 13 of the upper electrode sheet is pressed. As a result, the wiring connection portion 13 of the upper electrode sheet
Is a predetermined aperture height (the difference in height between the lower surface at the wiring connection portion of the upper film 5a and the lower surface at other portions) h
It is drawn. Thereby, the upper electrode sheet, the lower electrode sheet, and the spacer 6 that constitute the membrane switch are obtained.

Thereafter, the anisotropic conductive film 2 is temporarily pressure-bonded to the region where the upper wiring connection wiring 9c is formed on the lower film 5b by a heat laminating process, hand ironing, or the like. The separator (not shown) which protected the surface of No. 2 was peeled off. Thereafter, the lower electrode sheet and the upper electrode sheet are arranged with the surfaces on which the electrodes and the like are formed facing each other, and a spacer 6 is interposed therebetween. These are strictly overlapped and fixed by using an assembly jig or the like that can be positioned at a predetermined position.

Thereafter, a fused portion is formed by ultrasonic welding in a region where electrodes, wirings and the like are not formed, and the upper electrode sheet, the spacer, and the lower electrode sheet are bonded. Simultaneously with the ultrasonic fusion, the wiring connecting portion 13 where the upper wiring is formed and the region where the upper wiring connecting wiring 9c of the lower electrode sheet is formed are, for example, changed by using the heater chip 17, for example. Full pressure bonding is performed via the one side conductive film 2.

In the membrane switch according to the present embodiment having the above-described structure, the wiring connection portion 13 of the upper electrode sheet is drawn in advance into a shape locally protruding toward the lower electrode sheet. In the case where the wiring connection portion 13 on which the wiring 9a is formed and the upper wiring connection wiring 9c on the lower film 5b are bonded and fixed via the anisotropic conductive film 2 and are electrically connected, the upper electrode sheet The permanent stress generated in the wiring connection portion 13 in the direction of peeling off from the upper wiring connection wiring 9c is reduced. For this reason, the electrical conduction reliability as a switch can be improved.

Further, since it is not necessary to press down the wiring connecting portion 13 of the upper electrode sheet to be distorted downward, it is not necessary to provide a slit surrounding the wiring connecting portion 13 in the upper film 5a. Therefore, the degree of freedom in circuit design of the upper electrode sheet is increased, and circuit design can be facilitated.

Further, since no permanent stress is generated in the wiring connection portion 13 of the upper electrode sheet, distortion around the wiring connection portion 13 is reduced. For this reason, the key (SW) near the connection part
(Variation in load for recognizing ON between different keys) can be stabilized.

Note that the thickness t _s of the spacer 6 is 0.075.
mm, the wiring connection portion 13 of the upper electrode sheet
Is preferably set to about 0.08 to 0.12 mm. As shown in FIG. 3 (a), h <no small peel stress to be t _s is generated. Further, as shown in FIG. 3 (c), h> ( t s + 0.04mm) upper electrode sheet around the connecting portion and a large peeling stress extent being lifted upward is generated. Therefore, as shown in FIG. _{3 (b), (t s} + 0.02mm) ≦ h ≦ (t s +0.04
mm).

In this embodiment, the wiring connection 1
The anisotropic conductive film 2 is disposed between the lower electrode sheet 3 and the lower electrode sheet. In the present invention, any conductive adhesive can be used as long as an adhesive force and conduction in the thickness direction can be obtained. However,
The use of an anisotropic conductive adhesive makes it easier to cure the wiring connection as compared to the case of using an isotropic conductive adhesive (not anisotropic), Is small and the circuit is crushed at the time of adhesive fixing, since the adhesive has anisotropy even if the adhesive spreads and spreads between the circuits, a short circuit between the circuits can be prevented. As the anisotropic conductive adhesive, an anisotropic conductive film (ACF: An
In addition to isotropic conductive film), an anisotropic conductive paste (ACP) or the like can be used.

[0048]

As described in detail above, according to the present invention,
In the case where the first wiring and the connection wiring are bonded and fixed via a conductive adhesive at the wiring connection part and are electrically connected, a permanent stress generated in the wiring connection part in a direction separating from the connection wiring. Decrease. For this reason, the electrical conduction reliability as a switch can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a part of a membrane switch according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a method for forming an upper electrode sheet.

FIGS. 3A to 3C are schematic cross-sectional views showing a change in peeling stress generated in a wiring connection portion of an upper electrode sheet.

FIG. 4 is a schematic diagram showing a part of a keyboard used as an input device of a conventional personal computer.

FIG. 5A is a perspective view showing a key top portion of a keyboard, FIG. 5B is a perspective view showing a membrane switch,
(C) is a perspective view showing a support plate.

FIG. 6 is a plan view showing a lower electrode sheet of the membrane switch shown in FIG. 5 (b).

FIGS. 7A and 7B are sectional views showing a method of assembling the keyboard in the order of steps.

FIG. 8 is a cross-sectional view showing a state in which the wiring of the upper electrode sheet and the wiring for connecting the upper wiring of the lower electrode sheet are connected by an anisotropic conductive film.

[Explanation of symbols]

 1, 31; Membrane switch 2: Anisotropic conductive film 5a, 25a; Upper film 5b, 25b; Lower film 6, 26; Spacer 6a; Wiring connection openings 9a, 29a; Upper wiring 9c, 29c; Wiring 13, 33; Wiring connection 16a, 16b; Pressing die 17; Heater chip 21; Finger touching part 22; Supporting tool 23; Rubber cushion 23a; Main body 23b; Leg 23c; Protrusion 24; Base 24a; 27a, 27b; electrode 28; support plate 29b; lower wiring 31a; tail portion 31b; fused portion 32;

Claims (10)

[Claims] A first insulating film and a second insulating film disposed to face each other; a plurality of first electrodes provided on a surface of the first insulating film facing the second insulating film; A first wiring connected to the plurality of first electrodes; a wiring connection portion on which the first wiring is integrated; and a plurality of second wirings provided on a surface of the second insulating film facing the first insulating film. A connection wire connected to an electrode and an external terminal; a second wire connected to the plurality of second electrodes; and a wire interposed between the first insulating film and the second insulating film. A spacer having a wiring connection opening at a position where the integrated first wiring and the connection wiring match each other; and bonding and fixing the first wiring and the connection wiring at the wiring connection portion and electrically. A conductive adhesive that is electrically connected to the The membrane switch, wherein the first insulating film is formed so as to locally protrude toward the connection wiring at the wire connection portion. 2. The method according to claim 1, wherein the external terminal is provided on a tail formed on the second insulating film, and the spacer has a switch opening at a position where the first electrode and the second electrode match. The membrane switch according to claim 1, wherein 3. The projecting portion of the wiring connecting portion is formed by drawing with a press of a convex mold and a concave mold matching a predetermined projecting shape.
Membrane switch described in. 4. The method according to claim 1, wherein a depth of the projecting portion of the wiring connection portion is (t _s +0.02 mm) to (t _s +0.04 mm) with respect to a thickness t _{s of the} spacer. Item 4. The membrane switch according to any one of items 1 to 3. 5. The membrane switch according to claim 1, wherein the conductive adhesive is an anisotropic conductive adhesive. 6. A first insulating film having a plurality of first electrodes on one side, a first wiring connected to the plurality of first electrodes, and a wiring connection portion on which the first wirings are integrated, and one side. A second insulating film having a plurality of second electrodes, a second wiring connected to the plurality of second electrodes, and a connection wiring connected to an external terminal. An electrode is disposed to face the first insulating film and the second insulating film.
A step of interposing a spacer having a wiring connection opening at a position where the first wiring integrated with the wiring connection part and the connection wiring are aligned with the insulating film; In the method for manufacturing a membrane switch, the method further comprising: bonding and fixing the first wiring and the connection wiring to each other and electrically connecting the first wiring to the connection wiring. Forming an insulating film so as to locally protrude toward the connection wiring; and bonding and fixing both between the first wiring and the connection wiring at the wiring connection portion and electrically. After the step of arranging the conductive adhesive to be conducted and the step of interposing the spacer, the wiring connection portion on which the first wiring is integrated and the connection wiring are formed via the conductive adhesive. Second excellence Method for manufacturing a membrane switch and having a step for electrically conducting, together with a film and pressed fixedly bonded with the connection wiring and the first wiring. 7. The external terminal is provided on a tail formed on the second insulating film, and the spacer has a switch opening at a position where the first electrode and the second electrode match. The method for manufacturing a membrane switch according to claim 6, wherein 8. The step of forming the first insulating film in the wiring connection portion so as to locally protrude toward the connection wiring includes the step of forming a convex mold and a concave mold that match a predetermined projecting shape. The method for manufacturing a membrane switch according to claim 6, wherein drawing is performed by pressing. 9. The method according to claim 9, wherein a depth of the projecting portion of the wiring connection portion is (t _s +0.02 mm) to (t _s +0.04 mm) with respect to a thickness t _{s of the} spacer. Item 9. The method for manufacturing a membrane switch according to any one of Items 6 to 8. 10. The method of manufacturing a membrane switch according to claim 6, wherein the conductive adhesive is an anisotropic conductive adhesive.