JP7165624B2 - Force touch sensor and force touch sensor module - Google Patents

Description

The present invention relates to force-sensitive touch sensors and force-sensitive touch sensor modules.

BACKGROUND ART In various fields such as in-vehicle electronic devices, capacitive pressure-sensitive touch sensor modules capable of detecting pressure have been proposed as sensor modules for detecting operations on operation surfaces. For example, in Patent Document 1, a first electrode and a second electrode are provided on one surface of a base sheet, and the base sheet is folded in half so that the first electrode and the second electrode face each other. Furthermore, a pressure-sensitive touch sensor module is disclosed in which an elastic sheet is provided between the first electrode and the second electrode. In the pressure-sensitive touch sensor module, when the operation surface is pressed, the elastic sheet is compressed and deformed, the first electrode and the second electrode approach each other, the current of the second electrode changes, and the capacitance changes. do. By detecting this change in capacitance, it is possible to recognize the pressing of the operation surface.

JP 2010-217967 A

However, in the pressure-sensitive touch sensor module of Patent Document 1, the base sheet is large because it needs to be folded in half, and the cost is high.
As a method for reducing folding, it is conceivable to provide a folded portion that partially protrudes from the outer edge of the base material sheet, and to fold only the folded portion so that the first electrode and the second electrode are opposed to each other. However, in this case, it is necessary to arrange the first electrode and the second electrode closer to the outer edge of the base material sheet, which lowers the degree of freedom in arranging the electrodes. Further, when applied to a pressure-sensitive touch sensor module in which the central portion of the operation surface is a pressing portion, the pressing portion is separated from the first electrode and the second electrode. For this reason, especially in a pressure-sensitive touch sensor module that uses leather, rubber, or the like for the operation panel and has excellent flexibility, the pressure of the pressing portion is less likely to be transmitted to the elastic sheet between the first electrode and the second electrode. Recognition becomes difficult.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pressure-sensitive touch sensor module that is low-cost and has high pressure-sensitivity detection accuracy even if the pressure-sensitive touch-sensor module uses leather, rubber, or the like for the operation panel and has excellent flexibility. and

The present invention has the following configurations.
[1] A capacitive pressure-sensitive touch sensor that detects pressing,
A base sheet, a first electrode, a second electrode, and an elastic layer,
The first electrode and the second electrode are provided on any surface of the base sheet so as to be adjacent to each other on the surface,
Leaving at least part of a portion between the first electrode and the second electrode around one of the adjacent first electrode and the second electrode in the base sheet A cut is formed surrounding the electrode,
the folded portion surrounded by the cut of the base sheet is folded back so that the surfaces of the first electrode and the second electrode face each other;
The elastic layer is provided between the folded portions of the base sheet,
The elastic layer is compressed and deformed in the thickness direction by the pressing force, and the distance between the first electrode and the second electrode is reduced, and the pressing force is detected from the change in capacitance. touch sensor.
[2] The pressure-sensitive touch sensor according to [1], wherein a slit is formed in a part of the folding line between the first electrode and the second electrode adjacent to each other in the base sheet.
[3] The pressure-sensitive touch sensor according to [1] or [2], wherein the elastic layer is a rubber-like elastic body including a pair of sheet portions and a column portion sandwiched between the pair of sheet portions.
[4] The pressure-sensitive touch sensor according to any one of [1] to [3], further comprising a third electrode between the first electrode and the second electrode facing each other.
[5] A fourth electrode is further provided on the first surface of the base sheet, and a change in the capacitance of the fourth electrode due to contact or proximity of a conductor to the fourth electrode causes the The pressure-sensitive touch sensor according to any one of [1] to [4], which detects contact or proximity of a conductor to the fourth electrode.
[6] An operation panel having an operation surface, a frame member, and the pressure-sensitive touch sensor according to any one of [1] to [5],
A pressure-sensitive touch sensor module, wherein the pressure-sensitive touch sensor is sandwiched between the operation panel and the frame member.

According to the present invention, it is possible to provide a pressure-sensitive touch sensor with high pressure-sensitive detection accuracy, even if it is a low-cost pressure-sensitive touch-sensor module that uses leather, rubber, or the like for the operation panel and has excellent flexibility.

1 is a diagram showing an example of the pressure-sensitive touch sensor of the present invention, and is a plan view before folding back a folded portion; FIG. FIG. 2 is a plan view showing a state in which a folded portion of the pressure-sensitive touch sensor of FIG. 1 is folded; FIG. 2 is a cross-sectional view of the pressure-sensitive touch sensor of FIG. 1 taken along line AA; FIG. 3 is a BB cross-sectional view of the pressure-sensitive touch sensor of FIG. 2; FIG. 2 is a plan view showing a state before providing between folded portions of an elastic layer in the pressure-sensitive touch sensor of FIG. 1; FIG. 6 is a CC cross-sectional view of the elastic layer of FIG. 5; 1 is an exploded perspective view showing an example of a pressure-sensitive touch sensor module of the present invention; FIG. 1 is a cross-sectional view showing an example of a pressure-sensitive touch sensor module of the present invention; FIG. 5 is a flow chart showing the flow of processing for recognizing a touch on an operation surface by the pressure-sensitive touch sensor of the present invention; FIG. 10 is a diagram showing another example of the pressure-sensitive touch sensor of the present invention, and is a cross-sectional view before folding back the folded portion. FIG. 11 is a cross-sectional view showing a state in which the folded portion of the pressure-sensitive touch sensor of FIG. 10 is folded; FIG. 10 is a diagram showing another example of the pressure-sensitive touch sensor of the present invention, and is a plan view before folding back the folded portion; FIG. 13 is a plan view showing a state in which the folded portion of the pressure-sensitive touch sensor of FIG. 12 is folded; FIG. 14 is a DD cross-sectional view of the pressure-sensitive touch sensor of FIG. 13; FIG. 10 is a diagram showing another example of the pressure-sensitive touch sensor of the present invention, and is a plan view before folding back the folded portion; FIG. 16 is a plan view showing a state in which the folded portion of the pressure-sensitive touch sensor of FIG. 15 is folded; FIG. 10 is a diagram showing another example of the pressure-sensitive touch sensor of the present invention, and is a plan view before folding back the folded portion; FIG. 18 is a plan view showing a state in which the folded portion of the pressure-sensitive touch sensor of FIG. 17 is folded;

[Pressure-sensitive touch sensor]
The pressure-sensitive touch sensor of the present invention is a capacitive pressure-sensitive touch sensor that detects pressure. For example, by attaching the pressure-sensitive touch sensor of the present invention to the back surface of the operation panel, it is possible to detect pressure on the operation surface of the operation panel. An example of the pressure-sensitive touch sensor of the present invention will be described below.
It should be noted that the dimensions and the like of the drawings illustrated in the following description are only examples, and the present invention is not necessarily limited to them, and can be implemented with appropriate changes within the scope of not changing the gist of the present invention. .

As shown in FIGS. 1 to 4, the pressure-sensitive touch sensor 1 of this embodiment includes a base sheet 10, a protective layer 12, three first electrodes 14, three second electrodes 16, three It has three first auxiliary electrodes 18 , three second auxiliary electrodes 20 and three elastic layers 30 .

The pressure-sensitive touch sensor 1 of this example has a main body portion 1a which is rectangular in plan view, and a strip-shaped strip portion 1b extending from the short side of the main body portion 1a. In addition, the place where the band-shaped portion 1b extends from the main body portion 1a is arbitrary, and is not limited to the short side of the main body portion 1a. Alternatively, a pressure-sensitive touch sensor that does not have the band-shaped portion 1b may be used.

The shape of the base sheet 10 is not limited to the shape of this example, and can be appropriately set according to the application. The dimensions of the base sheet 10 are also not particularly limited, and can be appropriately set according to the application.
A transparent insulating film made of resin can be used as the base sheet. Here, "transparent" means that the light transmittance measured according to JIS K7136 is 50% or more. "Insulated" means that the electrical resistance value is 1 MΩ or more, preferably 10 MΩ or more.

Examples of the material forming the base sheet 10 include polyester such as polyethylene terephthalate (PET), polycarbonate (PC), acrylic resin, cyclic polyolefin resin, and triacetyl cellulose.
The material forming the base sheet may be of one type or two or more types.

The thickness of the base sheet 10 is preferably 10-250 μm, more preferably 25-188 μm. If the thickness of the base sheet 10 is at least the lower limit of the above range, it is easy to ensure sufficient strength and rigidity. If the thickness of the base sheet 10 is equal to or less than the upper limit of the above range, the thickness of the pressure-sensitive touch sensor can be easily reduced.

The protective layer 12 is laminated on the first surface 10a side of the base sheet 10 over the entire body portion 1a and strip portion 1b of the pressure-sensitive touch sensor 1 .
The shape and dimensions of the protective layer 12 are not particularly limited, and can be appropriately set according to the application.
The protective layer 12 is not particularly limited, and for example, the same transparent resin insulating film as that mentioned for the base sheet can be exemplified.

The thickness of the protective layer 12 is preferably 10-250 μm, more preferably 10-188 μm. If the thickness of the protective layer 12 is equal to or greater than the lower limit of the above range, it is easy to ensure sufficient strength and rigidity. If the thickness of the protective layer 12 is equal to or less than the upper limit of the range, the thickness of the pressure-sensitive touch sensor can be easily reduced.

A first electrode 14, a second electrode 16, a first auxiliary electrode 18, and a second auxiliary electrode 20 are provided on the first surface 10a of the base sheet 10 in the main body portion 1a. A protective layer 12 is laminated on. The second surface 10b of the base sheet 10 is the surface facing the operation panel.

The three pairs of first electrodes 14 and second electrodes 16 are provided adjacent to each other on the first surface 10a of the base sheet 10, respectively. That is, as shown in FIG. 1, in a state in which the folded portion 22 of the base sheet 10 is not folded, the first electrodes 14 and the second electrodes 16 are arranged adjacent to each other in plan view. .

The first auxiliary electrode 18 is provided in contact with the first electrode 14 over the entire circumference so as to surround the first electrode 14 . The second auxiliary electrode 20 is provided in contact with the second electrode 16 over the entire circumference so as to surround the second electrode 16 . The first auxiliary electrode 18 and the second auxiliary electrode 20 are connected by wirings 2a and 2b to a connection terminal portion 28 formed at the tip portion of the belt-shaped portion 1b. It is electrically connected to the capacitance detection part that does not work. This allows the first electrode 14 and the second electrode 16 to be electrically connected to the capacitance detection section.

By providing the first auxiliary electrode 18 and the second auxiliary electrode 20, the effects of resistance are less likely to occur than when the first electrode 14 and the second electrode 16 are in point contact with the wirings 2a and 2b. Become. Therefore, even when the first electrode 14 and the second electrode 16 are made of a conductive polymer having a relatively high resistance, high detection accuracy can be ensured.

A gap 24 is formed around the second electrode 16 in the base sheet 10 and the protective layer 12 to surround the second electrode 16 while leaving a space between the first electrode 14 and the second electrode 16. . As a result, in the base sheet 10, the rectangular folded portion 22 surrounded by the cuts 24 where the second electrodes 16 are arranged is hollowed out toward the first surface 10a to form the first electrode. It is folded back toward the electrode 14 side. When the folded portion 22 is folded back, the first electrode 14 and the second electrode 16 overlap when viewed from the thickness direction of the base sheet 10, and their surfaces face each other. The elastic layer 30 is arranged between the first electrode 14 and the second electrode 16 to form the pressure sensing portion 26 .

In the pressure-sensitive touch sensor of the present invention, even if the folded portion 22 is hollowed out toward the second surface 10b of the base sheet 10 and folded back toward the first electrode 14 side, good. In addition, around the first electrode 14 in the base sheet 10 and the protective layer 12, a gap 24 is formed to surround the first electrode 14 leaving a space between the first electrode 14 and the second electrode 16. A rectangular folded portion 22 surrounded by a cut 24 where one electrode 14 is arranged may be folded back toward the second electrode 16 side.

In this manner, in the pressure-sensitive touch sensor 1, the folded portions 22 surrounded by the cuts 24 around the second electrodes 16 are folded back so that the surfaces of the first electrodes 14 and the second electrodes 16 face each other. Thereby, even if the first electrode 14 and the second electrode 16 are arranged in the central portion of the base sheet 10, they can be easily made to face each other. In this manner, the degree of freedom in arranging the first electrode 14 and the second electrode 16 is high. Therefore, for example, the first electrode 14 and the second electrode 16 can be arranged at positions overlapping with or close to the pressing portion of the operation surface of the pressure-sensitive touch sensor module in accordance with the position of the pressing portion. . As a result, even in a highly flexible pressure-sensitive touch sensor module whose operation panel uses leather, rubber, or the like, the pressure applied to the pressing portion of the operation surface is firmly transmitted to the elastic layer 30, and the elastic layer 30 is thick. Since the capacitance is changed by sufficiently compressing and deforming in the direction, the pressure sensing accuracy is improved.

The cut line 24 may be formed continuously or intermittently as long as the cut line 22 can be folded back so that the surfaces of the first electrode 14 and the second electrode 16 can face each other. It may be formed in a broken line shape.
The width of the cut 24 can be set as appropriate, and can be, for example, 0 to 3 mm.
Although the plan view shape of the folded portion 22 formed by the cut 24 is rectangular in this example, it is not limited to a rectangular shape and can be set as appropriate.

In addition, linear slits 25 along the length direction of the folding line portion 15 are formed along the folding line portion 15 when folding back the folded portion 22 of the base sheet 10 and the protective layer 12. It is formed by leaving As shown in FIGS. 1 to 4, in the pressure-sensitive touch sensor 1, each folded portion 22 can be easily folded back using the slits 25. FIG. In general, when the base sheet is folded back, the vicinity of the folding line expands and tries to return to the original unfolded state. However, in the pressure-sensitive touch sensor 1, since the slit 25 is formed in the folding line portion 15, the force that causes the folded portion 22 to return to its original state is weakened. As a result, the distance between the first electrode 14 and the second electrode 16 is stabilized, so that the accuracy of detection of changes in capacitance due to pressure is increased, and erroneous detection of pressure is suppressed.

In this example, the slits 25 are formed continuously in the shape of a solid line, but the slits 25 may be formed in the shape of a broken line intermittently.
The length of the slit 25 can be appropriately set according to the length of the folding line portion 15 as long as the folded portion 22 is not separated from the base sheet 10 .
The width of the slit 25 can be appropriately set, for example, 0.5 to 10 mm, preferably 0.5 to 5 mm, more preferably 1 to 3 mm. If the width of the slit 25 is equal to or greater than the lower limit of the above range, it is easy to sandwich the elastic layer. If the width of the slit 25 is equal to or less than the upper limit of the above range, the product size is less likely to increase.

The shapes of the first electrode 14 and the second electrode 16 in this example are rectangular in plan view. Note that the shapes of the first electrode 14 and the second electrode 16 are not limited to rectangles, and can be designed as appropriate.
The dimensions of the first electrode 14 and the second electrode 16 are also not particularly limited, and can be, for example, approximately 10 mm long by 10 mm wide. As the first electrode 14 and the second electrode 16 are larger, the pressing force detection sensitivity is improved.

In the present invention, of the first electrode and the second electrode, the electrode farther from the operation surface may be smaller in size than the electrode closer to the operation surface. For example, in the pressure-sensitive touch sensor 1 , the second electrodes 16 may be sized smaller than the first electrodes 14 . As a result, when viewed from the thickness direction, the electrodes on the side far from the operation surface are less likely to protrude from the electrodes on the side close to the operation surface, thereby making it easier to suppress erroneous detection.

Of the first electrode 14 and the second electrode 16, the electrode arranged closer to the operation surface is preferably grounded. As a result, even if a finger approaches the pressure-sensitive detection unit 26 of the pressure-sensitive touch sensor 1 , the grounded electrode serves as a shield, thereby suppressing a change in capacitance. As a result, the effect of the finger approaching the pressure sensing unit 26, which is about to touch the operation surface, is eliminated from changes in the capacitance of the first electrode 14 and the second electrode 16, and the effect of the pressing force is eliminated. Since it can be limited to changes, erroneous detection of pressing can be further suppressed.

The first electrode 14 and the second electrode 16 may be pressure-sensitive electrodes of a known form, and may be self-capacitance or mutual-capacitance.
As a mode of the first electrode 14 and the second electrode 16, in the case of the self-capacitance method, the first electrode 14 and the second electrode 16 are sensing electrodes that independently sense changes in capacitance. , one of which is a detection electrode, and the other electrode is a GND electrode (grounded solid electrode). In the case of the mutual capacitance method, both the first electrode 14 and the second electrode 16 are solid electrodes, one of which is the Tx electrode, the other is the Rx electrode, and one of them is the GND electrode. and a comb-tooth electrode in which the Tx electrode and the Rx electrode are arranged in a comb-tooth shape.

As a mode of the first electrode 14 and the second electrode 16, a self-capacitance system is preferable in which the first electrode 14 and the second electrode 16 are detection electrodes that independently detect changes in capacitance. In this mode, it is easy to distinguish and detect the contact or proximity of the conductor and the pressure based on the respective signals from the first electrode 14 and the second electrode 16 .

The materials for the first electrode 14 and the second electrode 16 are not particularly limited, and electrodes commonly used as pressure-sensitive electrodes can be used. Examples thereof include metals such as copper and silver. Depending on the application, electrode materials such as indium-doped tin oxide (ITO), conductive polymers (polythiophene, polypyrrole, polyaniline, etc.), conductive nanowires (silver nanowires, gold nanowires, carbon nanotubes, etc.), silver paste, Carbon (carbon black, graphite, etc.), carbon nanotubes, etc. may be used. Silver paste is particularly preferable as the electrode material for the first electrode 14 and the second electrode 16 .
Here, "conductive" means having an electrical resistance value of less than 1 MΩ.

The thickness of the first electrode 14 and the second electrode 16 may be appropriately set according to the material.
The average thickness of the electrode containing the conductive polymer is preferably 0.1-5.0 μm, more preferably 0.1-2.0 μm.
The average thickness of the electrode comprising conductive nanowires is preferably 20-1000 nm, more preferably 50-300 nm.
The average thickness of the electrode containing metal particles, conductive metal oxide particles such as ITO, or carbon is preferably 0.01 to 25 μm, more preferably 0.1 to 15 μm.
The average thickness of the electrode made of the metal deposited film is preferably 0.01 to 1.0 μm, more preferably 0.05 to 0.3 μm.
The average thickness of the electrodes made of silver paste or carbon paste is preferably 1 to 25 μm.
If the average thickness of the electrode is at least the lower limit of the range, disconnection due to pinholes can be easily suppressed. If the average thickness of the electrode is equal to or less than the upper limit value of the range, thinning is facilitated.

The method of measuring electrode thickness varies depending on the thickness range. For example, in the case of a film thickness on the order of μm, the thickness can be measured by a micrometer, digimatic indicator, or laser displacement measurement. In addition, in the case of a film thickness smaller than the μm order, the thickness can be measured by cross-sectional observation using a scanning electron microscope or by a fluorescent X-ray analyzer.
The average thickness is the average thickness measured near the center of the electrode in plan view.

In this example, there are three first electrodes 14 and three second electrodes 16, but the number of first electrodes 14 and second electrodes 16 is not particularly limited. The number of first electrodes 14 may be two or less, or may be four or more. Similarly, the number of second electrodes 16 may be two or less, or four or more.

The material of the first auxiliary electrode 18 and the second auxiliary electrode 20 can be exemplified by the same material as the material of the first electrode 14 and the second electrode 16, preferably silver paste.
The preferred ranges of the average thickness of the first auxiliary electrode 18 and the second auxiliary electrode 20 are similar to the preferred ranges of the average thickness of the first electrode 14 and the second electrode 16 .

The material of the wirings 2a and 2b can be exemplified by the same material as the material of the first electrode 14 and the second electrode 16, preferably silver paste.
The preferred range of the average thickness of the wirings 2a, 2b is the same as the preferred range of the average thickness of the first electrode 14 and the second electrode 16. FIG.

The elastic layer 30 is a layer containing an elastic body, and is compressed and deformed by pressing. When the pressure-sensitive touch sensor 1 is pressed in the thickness direction, the elastic layer 30 is compressed and deformed in the thickness direction, and the distance between the first electrode 14 and the second electrode 16 becomes closer, thereby changing the capacitance. do. A press on the operation surface is recognized by detecting a change in this capacitance.

As shown in FIGS. 5 and 6, the elastic layer 30 of this example includes a pair of first sheet portion 30a and second sheet portion 30b, and a plurality of elastic layers sandwiched between the first sheet portion 30a and second sheet portion 30b. is a rubber-like elastic body provided with a column portion 30c. The first seat portion 30a, the second seat portion 30b and the plurality of column portions 30c are integrated. The elastic layer 30 has a space portion 30d around each column portion 30c.

An elastic member such as a sponge may be arranged in a space portion 30d other than the column portion 30c between the first sheet portion 30a and the second sheet portion 30b. This makes it easier to suppress damage to the base sheet 10 and the fold line portions 15 of the protective layer 12 due to excessive compressive deformation of the elastic layer 30 .

The materials forming the first sheet portion 30a, the second sheet portion 30b, and the plurality of column portions 30c may be the same or different. Of the elastic layer 30, only the column portion 30c that is compressively deformed needs to be made of an elastic material. The first sheet portion 30a and the second sheet portion 30b may be made of an elastic material, or may be made of an inelastic hard material. Examples of hard materials include resins other than elastomers, glass, metals, ceramics, and wood.

As the elastic material forming the elastic body of the elastic layer 30, it is preferable to use an elastic material that has an appropriate degree of compressive deformation in the thickness direction due to pressing and that has a good pressing feeling. Examples of elastic materials include thermosetting elastomers such as urethane rubber, isoprene rubber, ethylene propylene rubber, natural rubber, ethylene propylene diene rubber, styrene butadiene rubber, and silicone rubber; Thermoplastic elastomers such as butadiene-based or fluorine-based elastomers; or composites thereof. Among these, silicone rubber is preferable because it has a small dimensional change against repeated pressing, that is, a small compression set. The elastic material may be a foamed material with internal cells or a non-foamed material without substantial cells.
When a transparent elastic body is used for the elastic layer 30, an LED can be arranged on the back surface to realize character illumination.

The type A durometer hardness when measured according to JIS K 6253 with a thickness (height) of 1 cm of the elastic body forming the elastic layer 30 is preferably 85 or less. If the type A durometer hardness is 85 or less, it is easily elastically deformed when pressed. However, if the material is excessively soft, the recovery after elastic deformation is delayed, so the type A durometer hardness is preferably 10 or more.

The thickness of the first sheet portion 30a is preferably 5 to 100 μm, more preferably 10 to 100 μm. If the thickness of the first sheet portion 30a is equal to or greater than the lower limit value of the range, the bonding strength with the column portion 30c can be increased. If the thickness of the first sheet portion 30a is equal to or less than the upper limit value of the above range, the distance between the first electrode 14 and the second electrode 16 can be easily shortened when the operation surface is not pressed, and the pressing detection accuracy increases. can be made higher.
The preferable range of thickness of the second sheet portion 30b is the same as the preferable range of thickness of the first sheet portion 30a. The thickness of the first sheet portion 30a and the thickness of the second sheet portion 30b may be the same or different.

The shape of the columnar portion 30c is not particularly limited, and examples thereof include columnar shapes such as columnar shapes, truncated cone shapes, and prismatic shapes. Among them, a columnar shape and a truncated cone shape are preferable from the viewpoint of excellent durability. The shapes of the multiple pillars 30c may be the same or different.

The cross-sectional area of the single columnar portion 30c in the direction perpendicular to the height direction is not particularly limited, and is, for example, 0.005 to 4 mm ² , preferably 0.02 to 0.8 mm ² . If the cross-sectional area of the column portion 30c is equal to or greater than the lower limit value of the range, it becomes easy to compressively deform in the height direction when a pressing force is applied, and the column portion 30c is prevented from bending without being compressed. easy to prevent. If the cross-sectional area of the column portion 30c is equal to or less than the upper limit of the above range, it can be easily compressed and deformed with a moderate pressing force such as pressing with a finger.
Here, the cross-sectional area of the column means the area of the cross section orthogonal to the height direction at the half height position of the column. The cross-sectional area of the columnar portion can be measured by a known fine structure observation means such as an optical microscope measuring instrument.

The total cross-sectional area of all the columns 30c of the elastic layer 30 can be appropriately set according to the physical properties of the elastic material and the desired pressing comfort. When the area of the first sheet portion 30a or the second sheet portion 30b is 100%, the total cross-sectional area is preferably 0.1 to 30%, more preferably 0.5 to 20%, and 1 to 20%. is more preferred. If the total cross-sectional area is within the above range, it can be easily compressed and deformed with a moderate pressing force such as pressing with a finger.
Specifically, for example, the total cross-sectional area can be 1 to 100 mm ² .

The height of the columnar portion 30c is preferably 1 to 3000 μm, more preferably 50 to 2000 μm, even more preferably 200 to 1000 μm, particularly preferably 300 to 1000 μm. If the height of the column portion 30c is equal to or less than the upper limit value of the above range, the distance between the first electrode 14 and the second electrode 16 can be easily reduced when the operation surface is not pressed, and the pressing force detection accuracy can be improved. can be higher. In addition, the feeling that the operation surface is dented when the operation surface is pressed is easily suppressed, and it becomes easy to operate with the same feeling as touching a hard surface like a normal touch panel.
Here, the height of the column portion 30c does not include the thickness of the first sheet portion 30a and the thickness of the second sheet portion 30b. The height of the column portion 30c can be measured by a known fine structure observation means such as an optical microscope measuring instrument.

The column portion 30c is a member that supports the thickness of the elastic layer 30 by being connected to the thickness of the first sheet portion 30a and the second sheet portion 30b. If the thickness of the elastic layer 30 is the same regardless of the location, the heights of the plurality of columns 30c are substantially the same.

In this example, the arrangement pattern of the plurality of columns 30c in plan view is 5×5=25 in the vertical and horizontal directions in the thickness of the rectangular first sheet portion 30a and the planar direction of the second sheet portion 30b. It is a pattern in which pillars 30c of books are arranged at intervals. The arrangement pattern of the plurality of pillars 30c is not limited to this pattern, and may be, for example, a pattern in which the plurality of pillars 30c are arranged in a zigzag pattern.

The number of pillars 30c included in the elastic layer 30 may be plural or one. For example, one pillar portion 30c having a rectangular shape in plan view may be provided in the thickness of the first sheet portion 30a and the center region of the second sheet portion 30b in the plane direction. In this aspect, the elastic body forming the column portion 30c is preferably a foam containing air bubbles inside.

The number of columns 30c included in the elastic layer 30 is preferably 1 to 1000, more preferably 3 to 100, and even more preferably 4 to 50. When the number is equal to or greater than the lower limit of the range, the elastic layer 30 can be compressed and deformed with a moderate pressing force such as pressing the operation surface with a finger. If the number is equal to or less than the upper limit value of the range, it is possible to improve the detection accuracy of pressing by a finger.

The pitch between adjacent column portions 30c is preferably 0.1 to 5 mm, more preferably 0.5 to 3 mm. If the pitch is equal to or greater than the lower limit value of the range, the elastic layer 30 can be compressed and deformed with a moderate pressing force of pressing the operation surface with a finger. If the pitch is equal to or less than the upper limit value of the range, it is possible to improve the accuracy of detection of pressing by a finger.

The elastic layer 30 of this example is, as shown in FIG. It is arranged between the parts and adhered to the protective layer 12 via adhesive layers 36,38. Release papers 40 and 42 are laminated on the surfaces of the adhesive layers 36 and 38 as shown in FIGS. 5 and 6 before the folded portion 22 is placed between the folded portions.

The adhesive layers 36 and 38 may be provided only on part of the contact surface of the first base film 32 and the second base film 34 with the protective layer 12, respectively, or may be provided on the entire contact surface. good too. It is preferable that the adhesive layers 36 and 38 are provided on the entire contact surface because it is easy to make the pressing force on the elastic layer 30 uniform in the surface direction.

Examples of materials for the adhesive layers 36 and 38 independently include, for example, known curable adhesives (liquid adhesive before bonding) or adhesives (gel-like pressure-sensitive adhesive before bonding). . Also, each adhesive layer may be a substrate-type adhesive layer in which an adhesive or a pressure-sensitive adhesive is placed on both sides of a substrate layer. Examples of the substrate-type adhesive layer include a known double-sided tape.
Examples of the adhesives and adhesives include acrylic resins, urethane resins, ethylene-vinyl acetate copolymers, and the like. The curable adhesive may be of a solvent type containing a solvent that volatilizes during curing, or may be of a hot-melt type.

The thickness of the adhesive layers 36 and 38 may be, for example, 1 to 75 μm independently. The thickness of the adhesive layers 36 and 38 using the curable adhesive is preferably 1 to 20 μm. The thickness of the adhesive layers 36 and 38 using the adhesive is preferably 10 to 75 μm.

As a material for forming the first base film 32 and the second base film 34, an insulating resin material can be used. Examples include vinyl chloride (PVC), polymethyl methacrylate (PMMA), urethane, and the like. The resin forming the first base film 32 and the second base film 34 may be of one type or two or more types.

The thicknesses of the first base film 32 and the second base film 34 are independently, for example, 10 to 200 μm. When the resin material described above is used, its thickness is preferably 10 to 200 μm, more preferably 25 to 150 μm, even more preferably 25 to 100 μm.
When the thickness is equal to or greater than the lower limit of the range, it is easy to uniformize the pressing force against the elastic layer 30 in the plane direction. If the thickness is equal to or less than the upper limit value of the range, it is possible to improve the detection accuracy of input to the operation surface.

The first base film 32 and the second base film 34 are adhered to the outer surface of the first sheet portion 30a and the outer surface of the second sheet portion 30b of the elastic layer 30, respectively. These may be adhered by an adhesive layer (not shown), or may be directly adhered by a known surface treatment or heat treatment.
The bonding surfaces of the first base film 32 and the second base film 34 may be subjected to a known physical or chemical surface treatment for the purpose of improving the adhesive force.

The first base film 32 and the second base film 34 have smooth surfaces with respect to the elastic layer 30 so that the pressing force applied to the operation surface is uniformly transmitted to the elastic layer 30 . If the first base film 32 and the second base film 34 were not present, the unevenness of the portion where the first electrode 14 and the second electrode 16 were provided would cause the elastic layer 30 to be pressed unevenly. There is In this embodiment, since the first base film 32 and the second base film 34 are provided, the unevenness of the portion where the first electrode 14 and the second electrode 16 are provided prevents the elastic layer 30 from being pressed. Equalization effects can be reduced. Also, the first electrode 14 and the second electrode 16 are prevented from being locally damaged by the stress from the columnar portion 30c of the elastic layer 30. FIG.

For example, by providing an adhesive layer on the second surface 10b side of the base sheet 10, the pressure-sensitive touch sensor 1 can be attached to the operation panel via the adhesive layer. In this case, the portion of the pressure-sensitive touch sensor 1 where the adhesive layer is provided can be appropriately set within a range where the pressure-sensitive touch sensor 1 can be stably attached to the operation panel. For example, an adhesive layer may be provided on a portion of the base sheet 10 other than the band-shaped portion 1b, and the portion of the base sheet 10 other than the portion overlapping the band-shaped portion 1b, the folded portion 22, and the folded portion 22 of the main body portion 1a. An adhesive layer may be provided. In the case where no adhesive layer is provided in the base sheet 10 at the portion overlapping with the band-shaped portion 1b, the folded portion 22, and the folded portion 22 of the main body portion 1a, when the pressure-sensitive touch sensor 1 is attached to the back surface of the operation panel, the pressure-sensitive touch sensor 1 cannot be attached to the back surface of the operation panel. The pressure sensing portion 26 is no longer adhered to the operation panel. This mode eliminates the need to attach portions with different thicknesses at once when attaching the pressure-sensitive touch sensor 1, thereby suppressing air bubbles from entering the adhesive portion between the pressure-sensitive touch sensor 1 and the operation panel. It is advantageous in that it is easy to

The material forming the adhesive layer for attaching the pressure-sensitive touch sensor 1 to the operation panel is not particularly limited, and examples thereof include the same adhesives and pressure-sensitive adhesives as the adhesive layers 36 and 38 . Among them, the double-sided tape is preferable because the fixed area can be easily controlled.

When an adhesive layer is provided on the second surface 10b side of the base sheet 10, a release paper is pasted on the adhesive layer before being attached to the operation panel.
The release paper is not particularly limited, and known release papers can be used.

A manufacturing method of the pressure-sensitive touch sensor 1 is not particularly limited, and a known method can be used.
The first electrode 14, the second electrode 16, the first auxiliary electrode 18, and the second auxiliary electrode 20 can be manufactured, for example, by forming a pattern of an electrode material on the base sheet 10 by printing or the like. . Alternatively, electrodes may be formed on one side or both sides of the base material and attached to the base sheet 10 with an adhesive, a double-sided tape, or the like. Examples of the method of forming the electrodes include a method of printing a conductive paste followed by heating and curing, a method of printing an ink containing metal particles, a method of forming a metal foil or metal deposition film and patterning the paste, and the like. be done.

After forming the first electrode 14, the second electrode 16, the first auxiliary electrode 18, and the second auxiliary electrode 20, the protective layer 12 is attached to the first surface 10a side of the base sheet 10 with an adhesive or the like. are pasted together to form a laminate. Further, on the second surface 10b side of the base sheet 10, an adhesive layer is formed by attaching a double-sided tape or the like to the area excluding the portion where the folded portion 22 of the main body portion 1a is folded back, and a release paper is attached.

The elastic layer 30 can be manufactured, for example, by the following method. Specifically, the second sheet portion 30b is formed on one side of the second base film 34 by screen printing or the like. The surface of the second sheet portion 30b and the surface of each column portion 30c that is in contact with the second sheet portion 30b are irradiated with ultraviolet rays, and they are overlapped and pressed to join the second sheet portion 30b and each column portion 30c. . Also, the first sheet portion 30a is formed on one side of the first base film 32 by screen printing or the like. The surface of the first sheet portion 30a and the surface of each column portion 30c contacting the first sheet portion 30a are irradiated with ultraviolet rays, and the first sheet portion 30a and each column portion 30c are joined by overlapping and pressing them. . Thereby, the elastic layer 30 sandwiched between the first base film 32 and the second base film 34 can be formed.

The folded portion 22 of the base sheet 10 and the protective layer 12 is folded at the fold line 15 so that the first surface 10a of the base sheet 10 faces inside, and the first electrode 14 and the second electrode 16 are connected to each other. facing each other. Next, the elastic layer 30 is arranged between the folded parts and adhered to the protective layer 12 via the adhesive layers 36 and 38 . Thereby, the pressure-sensitive touch sensor 1 is obtained.

[Pressure-sensitive touch sensor module]
A pressure-sensitive touch sensor module of the present invention includes an operation panel having an operation surface, a frame member, and a pressure-sensitive touch sensor of the present invention, wherein the pressure-sensitive touch sensor of the present invention is sandwiched between the operation panel and the frame member. It is a device. Hereinafter, as an example of the pressure-sensitive touch sensor module of the present invention, a pressure-sensitive touch sensor module 100 (hereinafter also referred to as "module 100") including the pressure-sensitive touch sensor 1 will be described with reference to FIGS. 7 and 8. .

The module 100 includes a rectangular operation panel 110 having an operation surface 112 , a rectangular frame member 120 having four first protrusions 122 and three second protrusions 124 , and a pressure-sensitive touch sensor 1 . I have. The pressure-sensitive touch sensor 1 is attached to the back surface of the operation panel 110 via an adhesive layer with the release paper removed.

A method for attaching the pressure-sensitive touch sensor 1 to the operation panel 110 is not particularly limited, and examples thereof include a diaphragm method and a roller method. Among them, the diaphragm method is preferable because it is easy to prevent air bubbles from entering between the adhesive layer of the pressure-sensitive touch sensor 1 and the operation panel 110, and the pressure-sensitive touch sensor 1 can be adhered more neatly. .

The pressure-sensitive touch sensor 1 is sandwiched between the operation panel 110 and the frame member 120 with the folded portion 22 folded back and the elastic layer 30 provided between the folded portions. A frame member 120 is provided on the side where the folded portion 22 of the pressure-sensitive touch sensor 1 is folded, and an operation panel 110 is provided on the side opposite to the side where the folded portion 22 is folded. In this example, the operation panel 110 and the frame member 120 are connected by a spring 130 .
The surface of the operation panel 110 opposite to the pressure-sensitive touch sensor 1 serves as an operation surface 112 .

As the operation panel 110, a panel having such rigidity as to compress the elastic layer at a position away from the finger-pressed position through the panel can be used when the finger is pressed. However, if the position to be pressed is close to the position of the elastic layer, a panel with low rigidity such as leather or rubber may be used as the operation panel 110 . The operation panel 110 includes, for example, a cover layer covering the surface of the pressure-sensitive touch sensor 1 and a decorative layer formed on the surface of the cover layer. The cover layer may be a layer that also serves as a light guide layer that guides light rays from the light source in a planar direction.

Examples of materials for the cover layer include glass and resin.
Examples of resin include PC, acrylic resin, ABS resin, polystyrene (PS), PVC, PET, PBT, polyethylene naphthalate (PEN), and the like. These resins may be used individually by 1 type, and may use 2 or more types together.

The thickness of the cover layer is preferably 0.05 mm to 10 mm, more preferably 2 mm to 5 mm. When the thickness of the cover layer is at least the lower limit of the above range, sufficient strength is likely to be obtained. When the thickness of the cover layer is equal to or less than the upper limit of the range, it is easy to prevent the module 100 from becoming excessively thick.

The decorative layer is a layer on which arbitrary decoration is applied by decoration, letters, figures, symbols, patterns, a combination thereof, or a combination of these and colors. The decorative layer can be formed, for example, by printing on the cover layer.
Note that the operation panel 110 may not have a decorative layer.

The frame member 120 is provided with four first projections 122 having a rectangular shape in plan view at four corners on the surface on the pressure-sensitive touch sensor 1 side. When the pressure-sensitive touch sensor 1 is sandwiched between the operation panel 110 and the frame member 120 , the four first protrusions 122 are in pressure contact with the four corners of the pressure-sensitive touch sensor 1 .

In addition, three second protrusions 124 are provided at positions corresponding to the respective pressure-sensitive detection portions 26 of the pressure-sensitive touch sensor 1 at intervals in the length direction in the center portion of the frame member 120 in the width direction. It is When the pressure-sensitive touch sensor 1 is sandwiched between the operation panel 110 and the frame member 120 , the portion of the pressure-sensitive touch sensor 1 where the elastic layer 30 is located is sandwiched between the operation panel 110 and the second protrusion 124 of the frame member 120 . is in a state of

In the module 100 , the pressure-sensitive detection section 26 in which the first electrode 14 , the elastic layer 30 and the second electrode 16 overlap each other is press-contacted with the operation panel 110 by the second projection 124 of the frame member 120 . Fixed. Therefore, even if the pressure-sensitive detection unit 26 is not adhered to the operation panel 110, the performance is not deteriorated. If the pressure-sensitive detection portion 26 of the pressure-sensitive touch sensor 1 is not provided with an adhesive layer for adhering to the operation panel, the pressure-sensitive detection portion 26 will not be affected by the adhesive layer in pressure-sensitive detection. detection accuracy is higher.
Note that the first convex portion 122 and the second convex portion 124 may be adhered to the pressure-sensitive touch sensor 1 with an adhesive or the like.

In the present invention, it is preferable that the frame member has such a protrusion, and that the portion where the elastic layer of the pressure-sensitive touch sensor is located is sandwiched between the operation panel and the protrusion of the frame member. This makes it easier for the elastic layer 30 to be compressed and deformed even when it is pressed by a finger, so that the touch operation can be detected more accurately.

Materials for forming the frame member include, for example, resins, glass, and inorganic substances.
As the resin for forming the frame member, for example, the same resin as the resin for forming the cover layer can be used. The resin forming the frame member may be used singly or in combination of two or more.

In the present invention, a control board having a capacitance detection unit (IC) may be fixed inside the four first protrusions 122 on the surface of the frame member 120 on the pressure-sensitive touch sensor 1 side. . Furthermore, the control board may be connected to the connection terminal portion 28 of the pressure-sensitive touch sensor 1 via a connector. In addition to the capacitance detection unit (IC), the control board is mounted with an LED for character illumination, and the second electrode 16 of the pressure-sensitive touch sensor 1, the elastic layer 30, Characters may be illuminated through the first electrode 14 and the operation panel 110 .

An example of a touch operation determination process using the module 100 will be described below with reference to FIG. 9 . When both the first electrode 14 and the second electrode 16 are used as detection electrodes, the following aspects are possible.
The three pairs of first electrodes 14 and second electrodes 16 of the pressure-sensitive touch sensor 1 in the module 100 are each connected with an individual capacitive sensing part. Then, a first threshold value is set for each detection value detected by the capacitance detection unit connected to each first electrode 14 , and a specific first electrode 14 on the operation surface 112 of the operation panel 110 is set. When the portion corresponding to is touched, the detection value corresponding to the first electrode 14 is set to be equal to or greater than the first threshold. Further, a second threshold value is set for the detection value detected by the capacitance detection unit connected to the second electrode 16, and the detection value is equal to or more than the second threshold value when the electrode is pressed with a predetermined pressing force or more. be.

In this state, a finger presses a portion of the operation surface 112 of the operation panel 110 corresponding to one first electrode 14 . Then, the capacitance of the first electrode 14 first changes, and the detected value detected by the corresponding capacitance detection unit becomes equal to or greater than the first threshold. Further, when the elastic layer 30 of each pressure-sensitive detection part 26 is compressed and deformed by pressing, the distance between the first electrode 14 and the second electrode 16 is reduced and the capacitance changes, connection with the second electrode 16 is established. A detection value detected by the capacitance detection unit is greater than or equal to the second threshold. In this case, it is determined that the touch state is a pressing state with an intention to operate.

On the other hand, when the finger just approaches the operation surface 112 of the operation panel 110 without touching it, the detection value detected by the capacitance detection unit corresponding to each first electrode 14 is less than the first threshold. , is determined to be in a non-touch state.
Further, when a portion corresponding to one first electrode 14 on the operation surface 112 of the operation panel 110 is only touched and the portion is not pressed, capacitance detection corresponding to the first electrode 14 is performed. Although the detection value detected by the portion is greater than or equal to the first threshold value, the detection value detected by the capacitance detection portion corresponding to the second electrode 16 is less than the second threshold value. Therefore, when the finger simply touches the operation surface without any intention to operate it, it is determined that the operation surface is in the non-touch state.
Further, when a portion of the operation surface 112 of the operation panel 110 that does not correspond to the first electrodes 14 is pressed, the detection value detected by the electrostatic capacitance detection unit corresponding to each first electrode 14 changes to the first is less than the threshold, it is determined that the state is in the non-touch state.

As described above, in the present invention, at least one electrode between the first electrode and the second electrode is provided around one of the first electrode and the second electrode provided adjacent to the base sheet. A gap surrounding the electrode is formed leaving a portion, and the folded portion surrounded by the gap is folded back so that the first electrode and the second electrode are opposed to each other. As a result, the part where the base sheet is folded back is limited, and the cost can be reduced. In addition, the arrangement of the first electrode and the second electrode on the base sheet is not limited to the outer edge, and the arrangement of the electrodes is flexible. becomes higher. Therefore, the first electrode and the second electrode can be arranged at positions overlapping with or close to the pressing portion of the operation surface of the pressure-sensitive touch sensor module. As a result, even with a pressure-sensitive touch sensor module that uses leather, rubber, or the like for its operation panel and has excellent flexibility, the pressure applied to the pressing part of the operation surface is transmitted to the elastic layer, and the elastic layer expands in the thickness direction. Since the electrostatic capacitance is changed by sufficiently compressing and deforming, the pressure sensing accuracy is improved.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the first electrode and the second electrode can be provided on any surface of the base sheet, and may be provided on the second surface of the base sheet. Also, the first electrode and the second electrode may be provided on the same surface of the substrate sheet, or may be provided on different surfaces.

As shown in FIGS. 10 and 11, the pressure-sensitive touch sensor 2 may have a third electrode 50 between the first electrode 14 and the second electrode 16 facing each other. In the pressure-sensitive touch sensor 2, the first electrode 14 and the second electrode 16 are provided on the second surface 10b of the base sheet 10 so as to be adjacent to each other on the surface, and the second protective layer covers them. 12B are laminated. In addition, a third electrode 50 is provided at a position overlapping the first electrode 14 in the thickness direction on the first surface 10a of the base sheet 10, and the first protective layer 12A is laminated so as to cover it. there is

Cuts 24 are formed around the second electrodes 16 in the base sheet 10, the first protective layer 12A, and the second protective layer 12B in the same manner as in the pressure-sensitive touch sensor 1, and the folds surrounded by the cuts 24 are formed. Part 22 is adapted to be folded back. When the folded portion 22 is folded toward the first electrode 14 side, the surfaces of the first electrode 14 and the second electrode 16 are opposed to each other, and there is a gap between the first electrode 14 and the second electrode 16 . , the third electrode 50 is arranged.

By providing the third electrode 50 between the first electrode 14 and the second electrode 16 facing each other, the pressure sensing accuracy can be further improved.
As a form of the first electrode 14, the second electrode 16, and the third electrode 50, in the case of the self-capacitance method, for example, the first electrode 14 and the second electrode 16 are used as detection electrodes, and the third electrode is used as a GND electrode. In the case of the mutual capacitance method, for example, the first electrode 14 and the second electrode 16 are the Tx electrodes, and the third electrode is the Rx electrode. , a mode in which the third electrode is the Tx electrode, a mode in which the first electrode 14 and the second electrode 16 are comb-teeth electrodes of the Tx electrode and the Rx electrode, and a mode in which the third electrode is the GND electrode, the first electrode 14 is a comb-teeth electrode of Tx electrode and Rx electrode, the second electrode 16 is an Rx electrode, and the third electrode is a GND electrode.

Among them, the self-capacitance method, in which the first electrode 14 and the second electrode 16 are used as detection electrodes and the third electrode 50 is used as a GND electrode, is preferable because it is easy to distinguish and detect the contact or proximity of a conductor and the pressure. . If the third electrode 50 is used as a GND electrode, the effect of the proximity of the conductor on the second electrode 16 can be reduced, resulting in higher pressure sensing accuracy.

Forms such as material, shape, and thickness for forming the third electrode 50 are the same as those mentioned for the first electrode 14 and the second electrode 16, and preferred aspects are also the same. The size of the third electrode 50 when viewed in the thickness direction can be the same as that of the first electrode 14 and the second electrode 16, and when the third electrode 50 is the GND electrode, the size of the first It is preferably larger than the electrode 14 and the second electrode 16 .

The number of third electrodes 50 can be appropriately set according to the number of first electrodes 14 and second electrodes 16 . The number of third electrodes 50 may be the same as the number of first electrodes 14 and second electrodes 16, or may be different. For example, when the third electrode 50 is a GND electrode, one third electrode 50 having a large size is disposed across a plurality of pairs of the first electrodes 14 and the second electrodes 16. good too.

In the present invention, apart from the first electrode and the second electrode, a fourth electrode is further provided on the first surface of the base sheet, and the fourth electrode is formed by contacting or approaching the fourth electrode with the conductor. Contact or proximity of the conductor to the fourth electrode may be detected from changes in the capacitance of the electrodes. Specifically, for example, as shown in FIGS. 12 to 14, three pairs of first electrodes 14 and second electrodes 16 and three fourth electrodes 52 are provided. The pressure-sensitive touch sensor 3 may detect pressing with the second electrode 16 and detect contact or proximity of a conductor with the fourth electrode 52 .

In the pressure-sensitive touch sensor 3, three fourth electrodes 52 are provided at intervals in the lengthwise direction in the center of the first surface 10a of the base sheet 10 in the width direction. In addition, a first electrode 14 and a second electrode 16 that are adjacent in the length direction on the first surface 10a of the base sheet 10 are provided near the width direction of the first surface 10a of the base sheet 10. .

The fourth electrode 52 is an electrode that detects contact or proximity of a conductor to the fourth electrode 52 from a change in capacitance due to contact or proximity of the conductor to the fourth electrode 52 . The fourth electrode 52 functions as a touch electrode for detecting contact of a conductor with the operating surface in the pressure sensitive touch sensor module.

The shape of the fourth electrode 52 in this example is rectangular in plan view. Note that the shape of the fourth electrode 52 is not limited to a rectangular shape, and can be designed as appropriate. The dimensions of the fourth electrode 52 are also not particularly limited, and can be, for example, approximately 10 mm long by 10 mm wide.

The fourth electrode 52 may be self-capacitance or mutual-capacitance.
The mode of the mutual capacitance fourth electrode 52 is not particularly limited. A rectangular electrode pattern, a diamond pattern, etc., in which a plurality of strip-shaped receiving electrodes are formed on the other surface and extend in a direction orthogonal to the transmitting electrodes are exemplified.
The form of the self-capacitance fourth electrode 52 is not particularly limited, and examples thereof include solid electrodes such as circular, elliptical, and rectangular shapes, diamond patterns, and the like.

The material of the fourth electrode 52 includes the same materials as those of the first electrode 14 and the second electrode 16, and a transparent conductive film is preferable.
The preferred average thickness of fourth electrode 52 is the same as the preferred average thickness of first electrode 14 and second electrode 16 .
Although there are three fourth electrodes 52 in this example, the number of fourth electrodes 52 is not particularly limited. The number of fourth electrodes 52 may be two or less, or may be four or more.

The pressure-sensitive touch sensor 3 is provided with an auxiliary electrode 54 that is in contact with the fourth electrode 52 over the entire circumference so as to surround the fourth electrode 52 . The auxiliary electrode 54 is connected by the wiring 2c to a connection terminal portion 28 formed at the tip portion of the strip portion 1b, and is also electrically connected to a capacitance detection portion (not shown) via the connection terminal portion 28. be. This allows the fourth electrode 52 to be connected to the capacitance detection section.

The material of the auxiliary electrode 54 can be exemplified by the same material as the material of the first electrode 14 and the second electrode 16, preferably silver paste.
The preferred range for the average thickness of auxiliary electrode 54 is similar to the preferred range for the average thickness of first electrode 14 and second electrode 16 .

As shown in FIGS. 15 and 16, a pressure sensing device is provided with a first annular electrode 14A and a second electrode 16A, and a fourth electrode 52 and an auxiliary electrode 54 provided inside the first annular electrode 14A. It may be the touch sensor 4 .

As shown in FIGS. 17 and 18, two pairs of first The pressure-sensitive touch sensor 5 may be provided with a second electrode 14B and a second electrode 16B. In the pressure-sensitive touch sensor 5, the planar shape of the first electrode 14B and the second electrode 16B is rectangular, and the planar shape of the slit 25 is the same as that of the first electrode 14B and the second electrode 16B. It is circular in shape.

In the pressure-sensitive touch sensor of the present invention, among the first electrode and the second electrode that are adjacent to each other, at least part of the portion between the first electrode and the second electrode is formed around the first electrode. A gap may be left to surround the first electrode, and the folded portion surrounded by the gap may be folded back so that the first electrode and the second electrode face each other.
In addition, it is possible to appropriately replace the constituent elements in the above-described embodiment with well-known constituent elements without departing from the spirit of the present invention, and the modifications described above may be combined as appropriate.

Reference Signs List 1 to 5 Pressure-sensitive touch sensor 10 Base sheet 10a First surface 10b Second surface 12 Protective layer 14, 14A to 14C First electrode 15 Folding line , 16, 16A to 16C... second electrode, 18... first auxiliary electrode, 20... second auxiliary electrode, 22... folded portion, 24... break, 25... slit, 26... pressure-sensitive detection portion, 30... Elastic layer 50...Third electrode 52...Fourth electrode 54...Auxiliary electrode.

Claims (6)

A capacitive pressure-sensitive touch sensor that detects pressure,
A base sheet, a first electrode, a second electrode, and an elastic layer,
The first electrode and the second electrode are provided on any surface of the base sheet so as to be adjacent to each other on the surface,
Leaving at least part of a portion between the first electrode and the second electrode around one of the adjacent first electrode and the second electrode in the base sheet A cut is formed surrounding the electrode,
the folded portion surrounded by the cut of the base sheet is folded back so that the surfaces of the first electrode and the second electrode face each other;
The elastic layer is provided between the folded portions of the base sheet,
The elastic layer is compressed and deformed in the thickness direction by the pressing force, and the distance between the first electrode and the second electrode is reduced, and the pressing force is detected from the change in capacitance. touch sensor. 2. The pressure-sensitive touch sensor according to claim 1, wherein a slit is formed in a portion of the folding line between the adjacent first electrode and second electrode in the base sheet. 3. The pressure-sensitive touch sensor according to claim 1, wherein said elastic layer is a rubber-like elastic body comprising a pair of sheet portions and a pillar portion sandwiched between said pair of sheet portions. The pressure sensitive touch sensor according to any one of claims 1 to 3, further comprising a third electrode between the first electrode and the second electrode facing each other. A fourth electrode is further provided on the first surface of the base sheet, and a change in the capacitance of the fourth electrode due to contact or proximity of the conductor to the fourth electrode causes the fourth electrode to A force-sensitive touch sensor according to any one of claims 1 to 4, which senses contact or proximity of a conductor to an electrode. An operation panel having an operation surface, a frame member, and the pressure-sensitive touch sensor according to any one of claims 1 to 5,
A pressure-sensitive touch sensor module, wherein the pressure-sensitive touch sensor is sandwiched between the operation panel and the frame member.

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