JP2010085233A - Pressure sensitive sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure sensor capable of detecting a pressure even in the case of a small load, and removing a useless power consumption. <P>SOLUTION: This pressure sensitive sensor 120 is equipped with: the first substrate 5 equipped with the first electrode layer 7a formed on the surface; and the second substrate 6 arranged in the laminated state on the first substrate 5, and equipped with the second electrode layer 7b provided on a facing position to the first electrode layer 7a of the first substrate 5 on the surface. The pressure sensitive sensor 120 is also equipped with pressure sensitive ink layers 8a, 8b arranged so as to cover at least either of the first electrode layer 7a and the second electrode layer 7b, wherein an electric characteristic is changed by an applied pressing force; and a spacer 10 provided on the surface of the pressure sensitive ink layers 8a, 8b, for keeping insulating property between the first electrode layer 7a and the second electrode layer 7b during a non-pressing time. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive sensor for measuring a pressure distribution of a directional component perpendicular to a surface among external forces applied to the surface.

  Conventionally, as a sensor for distributing the pressure of an external force applied to a certain surface, for example, a sensor having a configuration as described in Patent Document 1 can be cited. As shown in FIG. 1 of the cited document 1, such a sensor is formed by laminating two films so that an air layer is separated by a spacer, and an upper electrode is disposed in an upper layer and a lower electrode is disposed in a lower layer. The pressure-sensitive ink layer is arranged between them.

  And when pressure is applied to the upper film, only the portion where pressure is applied becomes conductive in the vertical direction, so output is obtained only at the lower electrode corresponding to the intersection so that pressure distribution is detected. It is configured. For example, by providing the pressure-sensitive sensor inside the vehicle seat, it is possible to determine whether the occupant is sitting on the seat and to determine the physique of the occupant from the pressure distribution.

  That is, the pressure-sensitive sensor disclosed in the cited document 1 is arranged so that the spacer is sandwiched between the upper and lower films in order to provide an air layer between the upper and lower films. Then, when pressure is applied, the pressure sensitive ink layer comes into contact with the electrode by bending the upper film. In this case, the pressure applied to the upper film is measured by detecting a short circuit between both electrodes through the pressure-sensitive ink layer and a change in resistance value corresponding to the pressure applied to the pressure-sensitive ink layer.

  However, it has been difficult to stably control the contact between the pressure-sensitive ink layer and the electrode with a load due to problems such as the upper film sagging when the film sags over time. Therefore, the reproducibility of the resistance value between the pressure-sensitive ink and the electrode due to the load is low, and it is difficult to measure the pressure with high accuracy. Moreover, in the pressure sensitive sensor of the said structure, since it comprised so that an electrode might be arrange | positioned in the most part of the surface of a film, the pressure sensitive sensor could not be comprised by permeability | transmittance.

In order to solve such a problem, the present applicant has applied for a pressure-sensitive sensor having a structure in which a pair of electrodes is provided on the lower film and the pair of electrodes are covered with pressure-sensitive conductive layer ink. . In such a pressure-sensitive sensor, a pair of electrodes is provided on the lower film, and the pressure-sensitive conductive layer ink provided on the upper electrode normally covers the electrodes, so that a spacer for the air layer is provided between the upper film and the lower film. There is no need to place between films. Therefore, it can be set as the sensor of arbitrary shapes according to an electrode installation shape. By configuring the pair of electrodes in a frame shape, the central portion of the pressure sensor can be configured to be transparent, and a touch panel or the like can be disposed on the transparent portion.
JP 2002-48658 A

  However, in a pressure sensor with such a configuration, the change in resistance value of the pressure-sensitive conductive layer ink due to the load is small at a small load, so the amount of current flowing between the pressure-sensitive conductive layer ink and the electrode is almost constant, and pressure detection is not possible. It was difficult to carry out with high accuracy.

  In addition, even when no load is applied, the pair of electrodes has conductivity, so that wasteful power is consumed.

  Therefore, the technical problem to be solved by the present invention is to provide a pressure sensor that solves the above-described problem, can detect pressure even with a small load, and can eliminate waste of power consumption. .

  In order to solve the above technical problem, the present invention provides a pressure sensitive sensor having the following configuration.

According to the first aspect of the present invention, the first base material provided with the first electrode layer formed on the surface, and the first electrode layer of the first base material on the surface that is stacked on the first base material. A pressure sensitive sensor comprising a second base material provided with a second electrode layer provided at a position opposite to
A pressure-sensitive ink layer that is disposed so as to cover at least one of the first electrode layer or the second electrode layer, and whose electrical characteristics are changed by an applied pressing force;
An insulating spacer provided on the surface of the pressure-sensitive ink layer;
A pressure sensitive sensor is provided.

  According to the second aspect of the present invention, the first base material and the second base material are disposed in a region where the first electrode layer or the second electrode layer of the first base material and the second base material is not provided. A pressure-sensitive sensor according to the first or second aspect, characterized in that the pressure-sensitive sensor is bonded by a positioned adhesive layer.

  According to a third aspect of the present invention, in the first or second aspect, the pressure-sensitive ink layer is provided so as to cover the first electrode layer and the second electrode layer, respectively. A pressure sensitive sensor is provided.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the spacer is provided in the form of dots on the surface of at least one of the pressure-sensitive ink layers. Pressure sensor.

  According to a fifth aspect of the present invention, the pressure-sensitive ink layer and the electrode layer are provided in a frame shape around the first base material and the second base material, respectively. A pressure-sensitive sensor according to any one of the fourth aspect is provided.

  According to a sixth aspect of the present invention, the pressure-sensitive ink layer and the electrode layer are provided in the form of dots at the corners of the first base material and the second base material, respectively. A pressure-sensitive sensor according to any one of the fourth aspect is provided.

  According to a seventh aspect of the present invention, the first base material and the second base material are made of a transparent material, and a transparent window portion is provided in a portion where the first electrode layer and the second electrode layer are not provided. The pressure-sensitive sensor according to any one of the first to sixth aspects is provided. In the above aspect, the transparent window portion may include the transparent material itself, and the translucent portion may function as a transparent window. Of the transparent materials, the first electrode layer and the second electrode layer may be You may form by cutting out the part which is not provided.

  According to the eighth aspect of the present invention, there is provided the support member arranged in a stacked manner on the surface of the first base material or the second base material on which the first electrode layer and the second electrode layer are not provided. A pressure-sensitive sensor according to any one of the first to seventh aspects is provided.

  According to a ninth aspect of the present invention, the support material is provided on the back side of the position where the first electrode layer or the second electrode layer is provided. A pressure sensor is provided.

  According to the present invention, the first electrode layer or the second electrode layer facing the pressure-sensitive ink layer is normally separated from the pressure-sensitive ink layer by the spacer disposed on the surface of the pressure-sensitive ink layer. That is, even when the pressure-sensitive ink layer moves downward due to gravity, it is possible to prevent energization between the first electrode layer and the second electrode layer by the spacer when no load is applied. Moreover, even if the first or second substrate is bent over time, the spacer is not deformed, so that the pressure-sensitive ink layer and the first electrode layer or the second electrode layer are not in direct contact. On the other hand, when a pressing force is applied, the pressure-sensitive ink layer and the electrode easily come into contact with each other. Therefore, the resistance value between the pressure-sensitive ink layer and the electrode can be controlled by the load, and sensing can be reliably performed even at a low load. Note that the pressure-sensitive ink layer only needs to be configured to short-circuit a pair of electrodes, and therefore does not need to be disposed so as to cover all of the electrodes, and at least partially covers a pair of electrodes simultaneously. What is necessary is just to be comprised. For example, it may be provided only at the corner of the frame-like electrode.

  According to the second aspect of the present invention, the first base material and the second base material are provided by providing the adhesive layer in a region where the first electrode layer or the second electrode layer of the second base material is not provided. Since both base materials can be bonded without interposing an air layer between the base materials, an effect of preventing interference fringes can be obtained. Further, since the indicated area of the base material is increased by the adhesive layer, the base material does not deteriorate due to the sag.

  In the pressure-sensitive sensor of the present invention, the flexible film and the base material can be brought into contact with each other while maintaining insulation through the spacer, so that the electrode can have any shape. Therefore, the transparent window portion can be provided in the pressure sensor by forming the electrode in a frame shape or in the dot shape at the corner portion.

  According to the eighth aspect of the present invention, by providing the support material, it is possible to prevent the load applied to the sensor from being widely dispersed over the entire surface of the base material. Therefore, the load applied to the sensor can be reliably transmitted as the deflection of the substrate, and the sensing accuracy can be improved.

  Hereinafter, a pressure sensor according to an embodiment of the present invention will be described with reference to the drawings.

  The pressure-sensitive sensor of this embodiment constitutes a touch input device 100 that is configured integrally with a touch panel. The touch input device 100 can detect the pressure intensity of the pressure sensor 120 in addition to the position detection of the touch panel 110.

  For example, the touch input device 100 suitably functions as a touch input device for a display of an electronic device having a touch panel, particularly a portable electronic device such as a mobile phone or a game machine. As shown in FIG. 2, a decoration region 101 and a transparent window portion 102 are provided. When the touch input device 100 is disposed in the display display window of the housing of the electronic device, the display screen of the display panel 130 provided below the touch input device 100 can be viewed from the transparent window portion 102. As will be described later, the decoration region 101 is formed by a decoration film 2 having a frame-shaped decoration portion 2a provided around the touch input device 100, and a portion 2b where the decoration portion 2a is not formed is formed. It is formed as a transparent window portion 101.

  FIG. 1 is a cross-sectional view illustrating a layer configuration of the touch input device according to the present embodiment. The touch panel 110 of the touch input device 100 includes an upper electrode film 2 and a lower electrode sheet 3. The upper electrode film 3 and the lower electrode sheet 4 are bonded to each other by a double-sided adhesive tape (not shown) at the periphery of the electrode via an air layer.

  The upper electrode film 3 and the lower electrode sheet 4 are arranged on a surface of the electrode support films 3b and 4b, respectively, on the same surface as the transparent upper electrode 3a and the transparent lower electrode 4a. Is formed, and the outside is energized. A spacer 4c is provided between the transparent upper electrode 3a and the transparent lower electrode 4a, and is configured so that the transparent upper electrode 3 and the transparent lower electrode 4a provided on the respective opposing surfaces do not accidentally contact each other. .

  The spacer 4c can be obtained by forming a transparent photocurable resin into fine dots by a photo process. Further, a large number of fine dots can be formed by the printing method to form the spacer 4c.

  The upper electrode film 3 has a configuration in which a decorative film 2 is attached to the back surface of a transparent hard coat film 1 with a transparent adhesive (not shown), and a transparent electrode support film 3b is laminated. A transparent upper electrode 3a and a routing circuit are formed on the lower surface of the electrode support film 3b. In addition, the decorative film 2 is formed on the surface on which the decorative layer 2a is in contact with the hard coat film 1 by a method such as printing.

  The hard coat film 1 may be transparent and may be colorless and transparent or colored and transparent. By appropriately combining the pattern of the transparent cover film and the decoration layer, the pattern of the decoration region 101 of the input device 100 can be various designs. For example, when the hard coat film 1 is colored and transparent, and the decoration layer 2a is formed of a metal layer having a metallic luster, the decoration region 101 of the input device 100 can be a tinted color having a colored metallic luster.

  As the material of the hard coat film 1, a material having excellent transparency and excellent surface abrasion resistance is used. Examples thereof include general-purpose resins such as polyethylene terephthalate, polystyrene resin, polyolefin resin, ABS resin, AS resin, acrylic resin, and AN resin. In addition, general-purpose engineering resins such as polystyrene resins, polycarbonate resins, polyacetal resins, polycarbonate modified polyphenylene ether resins, polybutylene terephthalate resins, ultrahigh molecular weight polyethylene resins, polysulfone resins, polyphenylene sulfide resins, polyphenylene oxide resins, Super engineering resins such as polyarylate resin, polyetherimide resin, polyimide resin, liquid crystal polyester resin, and polyallyl heat-resistant resin are used.

  As described above, the decorative film 2 includes the decorative region 101 of the touch input device 100 formed by the decorative portion 2a, and the portion 2b where the decorative portion 2a is not provided is the transparent window portion 102 of the touch input device 1. Become. The decorative portion 2 is provided in a frame shape around the decorative film 2 and formed so that the transparent window portion 3 is formed in the center portion, for example, an electrode portion of the touch panel 110 or a pressure-sensitive sensor. It can also be used as a concealing part for electrodes (see FIG. 1).

  The decorative film 2 is formed by applying ink to the surface of a transparent film. As the ink constituting the decorative portion 2a, polyvinyl chloride resin, polyamide resin, polyester resin, polyacrylic resin, polyurethane resin, polyvinyl acetal resin, polyester urethane resin, cellulose ester resin, alkyd A colored ink containing a resin such as a resin as a binder and an appropriate color pigment or dye as a colorant may be used. As a method for forming the printing layer, a normal printing method such as an offset printing method, a gravure printing method, or a screen printing method may be used. In particular, the offset printing method and the gravure printing method are suitable for performing multicolor printing and gradation expression. In the case of a single color, a coating method such as a gravure coating method, a roll coating method, or a comma coating method may be employed. The printing layer may be provided entirely or partially depending on the decoration desired to be expressed.

  Moreover, the decoration part 2a may consist of what consists of a metal thin film layer, or a combination of a printing layer and a metal thin film layer. The metal thin film layer is for expressing metallic luster as the decorative portion 2a, and is formed by a vacuum deposition method, a sputtering method, an ion plating method, a plating method, or the like. In this case, a metal such as aluminum, nickel, gold, platinum, chromium, iron, copper, tin, indium, silver, titanium, lead, or zinc, or an alloy or compound thereof is used depending on the metallic luster color to be expressed. The metal thin film layer is usually formed partially. Moreover, when providing a metal thin film layer, in order to improve adhesiveness with another layer, you may provide a front anchor layer and a rear anchor layer.

  The lower electrode sheet 4 has a configuration in which a transparent lower electrode 4a and the like are formed on the surface of a transparent electrode support sheet 4b.

  As the material of the electrode support sheet 4b, a material having excellent transparency is used. For example, general-purpose resins such as polystyrene resin, polyolefin resin, ABS resin, AS resin, acrylic resin, and AN resin can be used. Also, general-purpose engineering resins such as polyphenylene oxide / polystyrene resins, polycarbonate resins, polyacetal resins, polycarbonate-modified polyphenylene ether resins, polybutylene terephthalate resins, ultrahigh molecular weight polyethylene resins, polysulfone resins, polyphenylene sulfide resins, polyphenylene oxides Super-engineering resins such as resin, polyarylate resin, polyetherimide resin, polyimide resin, liquid crystal polyester resin, and polyallyl heat-resistant resin can be used.

  In FIG. 1, a transparent lower electrode 4a and a lead-out electrode (not shown) are formed on the upper surface of the electrode support sheet 4b. The transparent lower electrode 4a is provided directly on the surface of the electrode support sheet 4b. However, the transparent lower electrode 4a may be formed by attaching a transparent film having a transparent electrode on the surface thereof to the electrode support sheet 4b. As the transparent resin film in this case, it is possible to use engineering plastics such as polycarbonates, polyamides, and polyether ketones, resin films such as acrylics, polyethylene terephthalates, and polybutylene terephthalates.

  The transparent lower electrode 4a and the transparent upper electrode 3a are composed of a transparent conductive film. Examples of the material for the transparent conductive film include a thin film of a metal oxide such as tin oxide, indium oxide, antimony oxide, zinc oxide, cadmium oxide, or ITO, or a conductive polymer. As a method for forming the transparent lower electrode 4a and the transparent upper electrode 3a, for example, the entire surface of the lower electrode sheet 4 or the transparent resin film 22 is electrically conductive using a vacuum deposition method, sputtering, ion plating, CVD method, roll coater method, or the like. After forming the conductive film, unnecessary portions are removed by etching. Etching is performed by forming a resist on the part to be left as an electrode by photolithography or screen method, and then immersing it in an etching solution such as hydrochloric acid or spraying the etching solution to form a conductive film on the part where the resist is not formed. Then, the resist is swelled or dissolved to be removed by dipping in a solvent. Etching with a laser is also possible.

  Next, the pressure sensitive sensor 120 will be described. FIG. 3 shows a partially enlarged view of the pressure sensor of FIG. The pressure-sensitive sensor 120 is arranged to adhere to the lower side of the touch panel 110 with an adhesive layer (thickness: 50 μm) (not shown). The pressure-sensitive sensor 120 has a configuration in which a first base material 5 and a second base material 6 are laminated and disposed with an adhesive layer 9 such as a double-sided adhesive tape. On the surface of the first base material 5 and the second base material 6, a first electrode 7a and a second electrode 7b are provided at positions facing each other. A first pressure-sensitive ink layer 8a and a second pressure-sensitive ink layer 8b are provided to cover the periphery of the electrodes 7a and 7b provided on the first base material 5 and the second base material 6, respectively. A dot spacer 10 is provided on the surface of the first pressure-sensitive ink layer 8a.

  The first base material 5 and the second base material 6 are made of a transparent material as shown in FIG. 5A (showing the configuration of the first base material as an example), and have a first pressure-sensitive ink layer 8a around them. The second pressure-sensitive ink layer 8b and the like are provided in a frame shape. An adhesive layer 9 is provided in a portion where the first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b are not provided, and the first base material 5 and the second base material 6 are bonded. With this configuration, it is possible to prevent occurrence of interference fringes without providing an air layer between the first base material 5 and the second base material 6.

  The material of the first base material 5 and the second base material 6 is a material that can be used for a flexible substrate, for example, polyethylene terephthalate, polystyrene resin, polyolefin resin, ABS resin, AS resin, acrylic resin, AN resin, etc. General-purpose resins. In addition, general-purpose engineering resins such as polystyrene resins, polycarbonate resins, polyacetal resins, polycarbonate modified polyphenylene ether resins, polybutylene terephthalate resins, ultrahigh molecular weight polyethylene resins, polysulfone resins, polyphenylene sulfide resins, polyphenylene oxide resins, Super engineering resins such as polyarylate resin, polyetherimide resin, polyimide resin, liquid crystal polyester resin, and polyallyl heat-resistant resin are used. In this embodiment, a 100 μm polyethylene terephthalate film is used for both the first base material and the second base material.

  As shown to FIG. 5A, the 1st base material 5 forms the transparent window part 5a located in the center part of the 1st pressure sensitive ink layer 8a provided in frame shape. The transparent window portion 5a functions as a viewing window of the display device 130. The second base 6 (not shown) includes a frame-shaped second pressure-sensitive ink layer 8 b provided at a position facing the first pressure-sensitive ink layer 8 a provided on the first base 5. A transparent window portion that functions as a viewing window of the display device 130 is formed in the inner portion of the frame.

  The first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b cover the first electrode layer 7a and the second electrode 7b provided on the surfaces of the first base material 5 and the second base material 6, respectively. It is provided as follows. In the present embodiment, the first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b are provided so as to cover the periphery of both the first electrode layer 7a and the second electrode 7b, respectively. It may be provided only in at least one (see FIG. 7). Further, it is not necessary to cover the entire surfaces of the first electrode layer 7a and the second electrode 7b, and only a part of the first electrode layer 7a and the second electrode 7b may be covered. In this case, in order to maintain insulation between the first electrode layer 7a and the second electrode 7b, for example, the pressure-sensitive ink layers of the first electrode layer 7a and the second electrode 7b are formed by an adhesive layer such as a double-sided tape. It is preferable that the portion not provided is covered so that both can be insulated.

  The composition constituting the first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b is composed of a material whose electrical properties such as an electrical resistance value change according to external force. Quantum tunneling composites available under the trade name “QTC” from Peratech are used. The first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b are provided on the upper film 5 by coating. As a method for applying the pressure-sensitive ink layer 8, a printing method such as screen printing, offset printing, gravure printing, or flexographic printing can be used.

  In the present embodiment, the thickness dimensions of the first base material 5, the second base material 6, the first pressure-sensitive ink layer 8a, and the second pressure-sensitive ink layer 8b are 100 μm, 100 μm, 20 μm, and 20 μm, respectively. The thickness C of the first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b includes the electrode layers 7a and 7b (both having a thickness of 10 μm) in order to cover the electrode layers 7a and 7b, respectively. It is the thickness dimension in a state.

  The material of the first electrode layer 7a provided on the first substrate 5 and the second electrode layer 7b provided on the second substrate 6 is a metal such as gold, silver, copper, or nickel, or carbon. A conductive paste is used. Examples of these forming methods include printing methods such as screen printing, offset printing, gravure printing, and flexographic printing, and a photoresist method. Alternatively, a metal foil such as copper or gold-plated copper may be attached, or an electrode pattern is formed with a resist on an FPC plated with a metal such as copper, and the portion of the metal foil that is not protected by the resist May be formed by etching.

  As shown in FIG. 1, a plurality of dot spacers 10 arranged along the extending direction of the electrodes are provided on the surface of the first pressure-sensitive ink layer 8 a provided on the first substrate 5. The dot spacer 10 may be made of a colored resin or may be made of a transparent resin. As shown in FIG. 4, the thickness dimension E of a dot spacer is 4-5 micrometers. The dot spacer 10 can be obtained by forming a photocurable resin into fine dots by a photo process. Moreover, it can also form by the screen-printing method which can make the thickness of a coating film more than fixed.

  In the present embodiment, the width dimension A of the first pressure-sensitive ink layer 8a is 2 mm. The size and arrangement density of the dot spacers, that is, the total area where the dot spacers are arranged per unit area, is preferably adjusted according to the area of the pressure-sensitive ink layer, and generally the surface of the first pressure-sensitive ink layer 8a. When the area of the dot spacer increases, the size of the dot spacer is increased or the arrangement density of the dot spacers is increased.

  As shown in FIG. 5B, the pressure-sensitive ink layers 8a and 8b provided on the first base material 5 and the second base material 6 do not need to be provided over the entire periphery of the frame, and face only a part thereof. It may be provided as follows. For example, as shown to FIG. 5B, you may provide in the dot shape only in the corner part of the 1st base material 5 and the 2nd base material 6. FIG. In this case, the pressure-sensitive ink layers 8 a and 8 b provided in the respective dot shapes are energized with each other by the routing electrode 12.

  When pressure-sensitive ink layers 8a and 8b are provided in the form of dots as shown in FIG. 5B, the pressure-sensitive adhesive layer 9 has through-holes at portions where the pressure-sensitive ink layers 8a and 8b are located as shown in FIG. 6A. It is preferable to use a double-sided tape with 9b. That is, as shown in FIG. 6B, the pressure-sensitive ink layers 8a and 8b can be fitted into the through-holes 9b of the double-sided tape to enable contact between them, and the first substrate 5 and the second substrate Since a wide area of the material 6 can be bonded, strong bonding can be realized. The double-sided tape is made of an insulating material and conceals the routing circuit 12, thereby preventing energization between the routing circuits provided on the first base material 5 and the second base material 6, respectively. Can do.

  As shown in FIG. 1, a coating plate 11 as a support material may be provided on the lower surface of the second substrate 6. As shown in FIG. 1, the contact plate 11 is provided on a portion of the lower surface of the second base 6 where the second pressure-sensitive ink layer 8 b is provided. By providing the contact plate 11, when a load is applied to the pressure-sensitive sensor, the portion of the pressure-sensitive ink layer 8b of the second substrate is instructed from below and the first substrate 5 is distributed without dispersing the applied load. It can be reliably transmitted as the force used for the deformation of. In the above example, the contact plate 11 is provided on the lower surface of the second base material 6, but may be provided on the upper surface side of the first base material 5. The thickness dimension of the contact plate is preferably about 50 to 200 μm, and in this embodiment, it is 150 μm (including the thickness of the adhesive layer for bonding to the second substrate).

  In the pressure sensor 120 having the above-described configuration, the first pressure-sensitive ink layer 8a and the second pressure-sensitive ink layer 8b are usually separated at 9 o'clock by the dot spacer 10 provided on the surface of the pressure-sensitive ink layer 8b. There is no contact. When there is contact for input on the touch input surface of the touch panel 110 provided in the upper layer, the first base material 5 is bent downward by the load applied to the touch panel 110, and the pressure-sensitive ink layer 8a, When the 8b is pressed against each other, the pressure-sensitive ink layers 8a and 8b come into contact with each other. For this reason, a current flows between the first electrode layer 7a and the second electrode layer 7b, and the pressing force to the input surface to the touch input device 100 is detected by detecting the current.

  Further, when the pressing force on the input surface to the touch input device 100 is increased, the external force applied to the pressure-sensitive ink layers 8a and 8b is increased, so that the electric resistance values of the pressure-sensitive ink layers 8a and 8b are decreased. Become. Thereby, the electric current which flows between the 1st electrode layer 7a and the 2nd electrode layer 7b increases. By detecting the external force applied to the pressure-sensitive ink layers 8a and 8b by detecting the change of the current into a voltage value, the pressing force to the input surface to the touch input device 100 can be detected. it can.

  Note that, as described above, the pressure-sensitive ink layers 8a and 8b and the routing circuit 12 of the pressure-sensitive sensor 120 are concealed by the decorative portion 2a of the decorative film 2 of the touch panel 110 and are not visually recognized from the outside. .

  As described above, the touch input device according to the present embodiment can detect the pressure intensity at the pressure sensor 120 in addition to the position detection at the touch panel. Furthermore, the pressure sensor is normally in a state where the two pressure sensitive ink layers 8a and 8b existing at the opposing positions are not in contact with each other by the dot spacer 10 provided on the surface of the pressure sensitive ink layer 8a. There is no waste of power consumption during normal times. Furthermore, the degree of contact between the pressure-sensitive ink layers 8a and 8b does not change due to the sag of the first base material over time.

  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. If the pressure-sensitive ink layers 8a and 8b are configured so as not to pass current between the pair of electrodes via the pressure-sensitive ink layer 8 in a state where the pressure-sensitive sensor is not pressed, the shape of the spacer and the pressure-sensitive ink layer The attachment positions of 8a and 8b are not particularly limited. For example, as shown in FIG. 7, the pressure-sensitive ink layer 8a may be provided only on the first electrode layer 7a, and the pressure-sensitive ink layer may not be provided on the second electrode layer 7b.

  Moreover, as shown in FIG. 7, you may provide a punching part in the center part of the 1st base material 5 and the 2nd base material 6, and may comprise the said part as a transparent window part. By providing the punched portion, the first base material 5 and the second base material 6 can be made of a coloring material.

It is sectional drawing which shows the layer structure of the touch input device concerning this embodiment. It is a schematic diagram which shows the external appearance structure of the touch input device of FIG. FIG. 2 shows a partially enlarged view of the pressure sensor of FIG. 1. It is an enlarged view of the part in which the pressure sensitive ink layer of the 1st substrate is provided. It is an example of laying of the 1st substrate provided in the 1st substrate. It is another example of installation of the 1st substrate provided in the 1st substrate. It is a figure which shows the structure of the contact bonding layer used for the pressure sensor at the time of using the 1st base material shown to FIG. 5B. It is the elements on larger scale which show the example of arrangement | positioning of the contact bonding layer and pressure-sensitive ink layer of FIG. 6A. It is sectional drawing which shows the layer structure of the touch input device concerning a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hard coat film 2 Decorative film 3a Transparent upper electrode 3b Electrode support film 4a Transparent electrode 4b Electrode support sheet 4c Dot spacer 5 First base material 6 Second base material 7a First electrode layer 7b Second electrode layer 8a First sense Pressure ink layer 8b Second pressure sensitive ink layer 9 Adhesive layer 10 Dot spacer 11 Address plate 12 Routing circuit 100 Touch input device 101 Decorating area 102 Transparent window portion 110 Touch panel 120 Pressure sensor 130 LCD

Claims (9)

A first base material provided with a first electrode layer formed on the surface, and a second base material laminated on the first base material and provided at a position facing the first electrode layer of the first base material on the surface A pressure sensitive sensor comprising a second substrate comprising an electrode layer,
A pressure-sensitive ink layer that is disposed so as to cover at least one of the first electrode layer or the second electrode layer, and whose electrical characteristics are changed by an applied pressing force;
A spacer that is provided on the surface of the pressure-sensitive ink layer and maintains insulation between the first electrode layer and the second electrode layer when not pressed;
A pressure-sensitive sensor comprising:   The first base material and the second base material are bonded by an adhesive layer located in a region where the first electrode layer or the second electrode layer of the first base material and the second base material is not provided. The pressure-sensitive sensor according to claim 1.   The pressure-sensitive sensor according to claim 1, wherein the pressure-sensitive ink layer is provided so as to cover the first electrode layer and the second electrode layer, respectively.   The pressure sensor according to any one of claims 1 to 3, wherein the spacer is provided in a dot shape on a surface of at least one of the pressure-sensitive ink layers.   The pressure-sensitive ink layer and the electrode layer are provided in a frame shape around the first base material and the second base material, respectively, according to any one of claims 1 to 4. Pressure sensitive sensor.   5. The pressure-sensitive ink layer and the electrode layer are provided in a dot shape at corners of the first base material and the second base material, respectively, according to claim 1. Pressure sensitive sensor.   The first base material and the second base material are made of a transparent material, and a transparent window portion is formed in a portion where the first electrode layer and the second electrode layer are not provided. The pressure-sensitive sensor according to any one of claims 1 to 6.   2. A support material arranged to be laminated on a surface of the first base material or the second base material on the side where the first electrode layer and the second electrode layer are not provided. The pressure-sensitive sensor according to any one of 7 to 7.   The pressure-sensitive sensor according to claim 8, wherein the support material is provided on a back surface side of a position where the first electrode layer or the second electrode layer is provided.

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