JP2024065854A - Tactile Sensor - Google Patents

Abstract

To provide a tactile sensor having less possibility of being damaged.SOLUTION: A tactile sensor includes: a first laminate obtained by laminating a first electrode and a conductive first resin layer in order from a first base material side; a first insulating layer surrounding the first laminate and provided to be separated from the first laminate on one surface of the first base material; a second base material facing the one surface of the first base material; a second laminate provided at a position facing the first laminate on the surface facing the first base material, of the second base material and obtained by laminating a second electrode and a conductive second resin layer in order from a second base material side; and a second insulating layer surrounding the second laminate and provided to be separated from the second laminate on the surface facing the first base material, of the second base material. The first insulating layer includes an inner insulating layer surrounding the first laminate and an outer insulating layer surrounding the inner insulating layer and provided to be separated at a predetermined distance from the inner insulating layer; and the second insulating layer is positioned between the inner and outer insulating layers.SELECTED DRAWING: Figure 1

Description

The present invention relates to a tactile sensor that detects shear force.

A pressure sensor that detects pressure or shear stress is known to have a structure in which a conductive layer or a resin layer is sandwiched between two opposing electrodes. In this pressure sensor, the conductive layer or the resin layer changes its physical quantity between the electrodes when an external force is applied, and the pressure or shear force (shear stress) can be detected based on the change in the physical quantity between the electrodes.

For example, Patent Document 1 describes a resistive pressure sensor that has a pair of conductive layers and a pair of resistor layers covering each of the conductive layers between two opposing substrates, and utilizes the fact that the inter-electrode resistance value changes as the conductive layers deform when a force is input.
It is being done.

Patent document 2 also describes a tactile sensor in which a conductive and flexible magnetic rubber body is attached between two rectangular electrodes, and the sensor detects a shear force applied in a direction parallel to the contact surface (shear direction) based on the change in the amount of current between the electrodes that changes in response to the deformation of the magnetic rubber body.

When detecting changes in resistance, the detection layer is formed by sandwiching conductive rubber between two opposing electrodes, or by printing electrodes directly onto the conductive layer, or by creating two electrodes with conductive layers printed on them and overlapping the conductive layers.

However, when sandwiching conductive rubber between electrodes, the contact state between the conductive rubber and the electrodes can become noise during sensor detection. Also, when printing electrodes directly on the conductive layer, in principle the conductive layer detects signals by deforming, but if the conductive layer is made thin in order to reduce the size of the sensor, it cannot deform sufficiently in response to an applied external force, resulting in poor detection accuracy.

For this reason, attention has been focused on a method in which two electrodes are printed with conductive layers and then these conductive layers are stacked together. This configuration is easy to manufacture, and has the advantage that it is easy to detect because the resistance value changes when the distance between the opposing electrodes changes due to an external force.

Japanese Patent No. 3664622 JP 2013-232293 A

This type of tactile sensor can measure shear force by the relative movement of the upper and lower opposing electrodes before and after the input of shear force. However, when a large shear force is applied, the overlap between the upper and lower electrodes disappears, making it impossible to detect changes in resistance value. Furthermore, when a large shear force is applied, there is a risk that the sensor will be damaged and the upper and lower electrodes will not return to their initial positions (the ideal positions when no shear force is being input).

Therefore, the present invention aims to provide a tactile sensor that is less susceptible to damage.

A first substrate, a first laminate provided on one side of the first substrate, in which a first electrode and a first resin layer having electrical conductivity are laminated in this order from the first substrate side, a first insulating layer provided on one side of the first substrate, surrounding the first laminate and spaced apart from the first laminate, a second substrate facing one side of the first substrate, a second laminate provided on a surface of the second substrate facing the first substrate at a position facing the first laminate, in which a second electrode and a second resin layer having electrical conductivity are laminated in this order from the second substrate side, and a first substrate of the second substrate. A tactile sensor comprising a second insulating layer on the opposing surface, surrounding the second laminate and spaced apart from the second laminate, capable of detecting applied shear force based on a change in electrical resistance between the first electrode and the second electrode depending on the overlapping area of the first resin layer and the second resin layer, the first insulating layer including an inner insulating layer surrounding the first laminate and an outer insulating layer surrounding the inner insulating layer and spaced a predetermined distance from the inner insulating layer, and the second insulating layer located between the inner insulating layer and the outer insulating layer.

The present invention provides a tactile sensor that is highly reproducible and has a low risk of breakage.

1 is a schematic diagram showing a schematic configuration of a tactile sensor according to an embodiment of the present invention. FIG. 4 is a schematic diagram showing an example of the arrangement of a laminate on a first substrate. FIG. 4 is a schematic diagram showing an example of the arrangement of a laminate on a second substrate. FIG. 4 is a cross-sectional view of the pressure sensor when measuring a shear force. 1 is a cross-sectional view showing a schematic configuration of a tactile sensor according to an embodiment of the present invention.

The following describes an embodiment of the present invention. The shape and number of electrodes are merely examples, and are not limited to the specific examples described here. In addition, to simplify the explanation, the figures are drawn at ratios different from the actual dimensions, but this does not detract from the gist of the technology related to the present invention.

1 is a schematic diagram showing the general configuration of a tactile sensor according to an embodiment of the present invention, and more specifically, FIG. 1(a) is a plan view of the tactile sensor, and FIG. 1(b) is a cross-sectional view taken along line A-A' in FIG. 1(a). For convenience, FIG. 1(a) shows the second substrate 2 and the resin layer in a see-through state. FIG. 2 is a schematic diagram showing an example of the arrangement of a laminate on a first substrate, and more specifically, FIG. 2(a) is a plan view, and FIG. 2(b) is a cross-sectional view taken along line B-B' in FIG. 2(a). FIG. 3 is a schematic diagram showing an example of the arrangement of a laminate on a second substrate, and more specifically, FIG. 3(a) is a plan view, and FIG. 3(b) is a cross-sectional view taken along line C-C' in FIG. 3(a).

The tactile sensor 100 includes a first substrate 1, a second substrate 2 facing the first substrate 1, a first laminate 11 and a second laminate 12 provided between the first substrate 1 and the second substrate 2, a first insulating layer 15, and a second insulating layer 16. The tactile sensor 100 is a sensor capable of detecting a shear force applied to the substrate. Shear refers to a force component in the surface direction of the substrate.

(Base material)
The first substrate 1 and the second substrate 2 may be made of any material as long as they are flexible, and may be selected appropriately according to the conditions of the electrodes formed by printing ink, photolithography, and the application as a sensor, such as plastic films, e.g., PET, PEN, and polyimide, and paper. The first substrate 1 and the second substrate 2 may be made of different types or thicknesses.

(Laminate)
The first laminate 11 is provided on one surface (the surface facing the second substrate 2) of the first substrate 1, and has, in order from the first substrate 1 side, a first electrode 11a and a first resin layer 11b laminated on the first electrode 11a. The second laminate 12 is provided on one surface (the surface facing the first substrate 1) of the second substrate 2, and has, in order from the second substrate 2 side, a second electrode 12a and a second resin layer 12b laminated on the second electrode. The first laminate 11 and the second laminate 12 face each other between the first substrate 1 and the second substrate 2.

The first laminate 11 and the second laminate 12 may each be provided in one or more units, but two units may be provided as shown in FIG. 1. In the case of two units, it is possible to detect shear forces in two axial directions. Specifically, it is possible to detect shear forces in a first direction (X-axis direction in FIG. 1) using one of the first laminates 11 (first laminate 11X) and one of the second laminates facing it (second laminate 12X), and it is possible to detect shear forces in a second direction (Y-axis direction in FIG. 1) perpendicular to the first direction using the other of the first laminate (first laminate 11Y) and the other of the second laminate facing it (second laminate 12Y). When the direction of shear to be detected is determined to be one direction, one first laminate 11 and one second laminate 12 are sufficient. In addition, by increasing the number of laminates, it is possible to measure the shear force more accurately. For example, in order to improve accuracy, an additional laminate may be provided in a third direction that is not perpendicular to the first and second directions. Increasing the number of layers is effective when you want to increase the measurement resolution, even if the shear detection direction of the object being measured is perfectly specific.

(electrode)
The first electrode 11a and the second electrode 12a have a shape (U-shape) in which two rectangular small electrodes are arranged side by side. Specifically, the first electrode 11a and the second electrode 12a of the first laminate 11X and the second laminate 12X capable of detecting the shear force in the X-axis direction have a pair of small electrodes extending in the Y-axis direction and a connection part that electrically connects the pair of small electrodes. In addition, the first electrode 11a and the second electrode 12a of the first laminate 11Y and the second laminate 12Y capable of detecting the shear force in the Y-axis direction have a pair of small electrodes extending in the X-axis direction and a connection part that electrically connects the pair of small electrodes. Each pair of small electrodes is arranged in parallel with a predetermined interval. As a result, compared to the case in which each of the first electrode 11a and the second electrode 12a is formed as a single square, the area change when the first electrode 11a and the second electrode 12a are shifted up and down is large, and the detection sensitivity can be improved. In addition, assuming that the tactile sensor 100 is attached to a finger for use, it is preferable that each small electrode is sized not to exceed 4 mm x 4 mm, since multiple small electrodes can be arranged on the pad of the finger. The shape and size of the first electrode 11a and the second electrode 12a can be freely selected according to the size of the measurement object, and may be, for example, a square. In this case, the alignment of the first electrode 11a and the second electrode 12a with respect to the substrate can be simplified, so that the difficulty of manufacturing can be reduced. In addition, the first electrode 11a and the second electrode 12a, which face each other vertically, are shifted from each other (partially not overlapping) in the direction of the detectable shear force as shown in FIG. 1 when no shear force is input, and are arranged so that the overlap area increases or decreases depending on the direction when a shear force is input. This makes it possible to detect the direction of the shear force. The amount of shift is preferably half the width of each small electrode. This makes the width of the increase and decrease in the overlap of the electrodes the same, allowing symmetrical measurement.

The first electrode 11a and the second electrode 12a are generally formed using a paste in which a precious metal powder of several micrometers to several tens of nanometers is mixed with a thermosetting resin, but carbon, aluminum, an alloy, or a mixture of these may also be used. The first electrode 11a and the second electrode 12a can be formed using a known printing method such as screen printing or gravure offset printing. They may also be formed by etching a plated or sputtered film. Although not shown, alignment marks may be provided on the substrate in order to form the first electrode 11a and the second electrode 12a. There are no particular limitations on the shape or size of the marks.

Wiring (leads) are connected to the first electrode 11a and the second electrode 12a, and signals are taken from the ends of the leads (the lead ends are not shown in the figure). Any routing is acceptable for the path along which the leads are formed as long as the leads do not cross each other along the way, but considering the miniaturization of the tactile sensor 100, it is preferable to concentrate the leads in one place at the end of the substrate.

(Resin Layer)
The first resin layer 11b and the second resin layer 12b serve as detection layers, and conductive materials are selected for the tactile sensor 100 to detect changes in resistance between opposing electrodes. The first resin layer 11b and the second resin layer 12b are formed so as to completely cover the first electrode 11a and the second electrode 12a, respectively, and to be separated from other resin layers formed on the same substrate. If the resin layers on the same substrate come into contact with each other, noise will be generated and the detection accuracy will decrease, which is not preferable. The first resin layer 11b and the second resin layer 12b are formed to have the same size. This makes it possible to prevent the electrodes on one substrate from protruding from the resin layer formed on the electrodes of the other substrate when the first substrate 1 and the second substrate 2 are displaced relative to each other, stabilizing signal detection.

The first resin layer 11b and the second resin layer 12b are made of a material that is conductive and has a resistivity higher than that of the first electrode 11a and the second electrode 12a. If the resistivity is too small, it is difficult to capture signal changes, and if the resistivity is large, the detection signal will have a lot of noise. The resistivity is more preferably 5 Ωcm or more and 500 Ωcm or less. Specifically, conductive polymers such as polyethylenedioxythiophene, polyaniline, and polypyrrole, carbon pastes using graphite and carbon nanotubes, and materials whose resistivity is adjusted by mixing these with an adjuster such as medium can be used.

The first resin layer 11b and the second resin layer 12b can be formed using a known printing method such as screen printing or a known coating method such as spray coating, but in order to selectively form them only near each electrode, it is preferable to use a printing method that allows formation by a single printing step.

In the tactile sensor 100, the resistance between the electrodes changes as the first resin layer 11b and the second resin layer 12b, which face each other vertically, shift relative to one another in the direction in which a shear force is applied, and the shear force is detected based on the change in resistance. Therefore, if the deformation of the first resin layer 11b and the second resin layer 12b caused by the input of the shear force is large relative to the shift between the first resin layer 11b and the second resin layer 12b, the noise dependent on the deformation also increases, and the detection accuracy also decreases. Therefore, it is preferable that the Young's modulus of the first resin layer 11b and the second resin layer 12b is 1000 MPa to 5000 MPa. If the Young's modulus is less than 1000 MPa, there is a possibility that the input of shear will cause deformation to a degree that cannot be ignored. On the other hand, a material with a Young's modulus of more than 5000 MPa is too hard and may not be able to adhere to the substrate or the electrodes. It is more preferable that the Young's modulus is 2000 MPa to 5000 MPa.

(First insulating layer)
The first insulating layer 15 is a member for limiting the relative amount of displacement between the first substrate 1 and the second substrate 2 when a shear force is applied, by combining with the second insulating layer 16 described later. The first base material 1 includes an inner insulating layer 15a provided on one side thereof, surrounding the first laminate 11 and spaced a predetermined distance from the first laminate 11, and an outer insulating layer 15b surrounding the inner insulating layer 15a and spaced a predetermined distance from the inner insulating layer 15a. In the figure, the first insulating layer 15 has a square shape in a plan view, but may have a circular shape or the like, and a shape may be appropriately selected so that the input of the shear force to the base material is uniform depending on the arrangement of the electrodes, etc.

The distance between the first laminate 11 and the inner insulating layer 15a is d1, and the distance between the inner insulating layer 15a and the outer insulating layer 15b is d2 (see FIG. 1(b)). The distance d1 is determined based on the amount of relative displacement between the first substrate 1 and the second substrate 2 that occurs when a shear force is input. The distance d1 is preferably in the range of 0.5 to 2 times the overlap width of the first electrode 11a and the second electrode 12a facing each other in a planar view, and more preferably 1 time. The distance d2 is preferably twice d1. When the first laminate 11 is displaced in a direction in which the overlap width increases with respect to the first electrode 11a and the second electrode 12a due to the input of a shear force, the resistance value between the upper and lower electrodes decreases, so that the signal increases until the opposing first laminate 11 and second laminate 12 completely overlap, but if it is displaced further, the overlap decreases, so the signal starts to decrease, and it becomes impossible to correspond to the shear force. By setting the distance at which the overlap between the opposing first electrode 11a and second electrode 12a does not decrease to d2, it is possible to correspond the shear force to the signal change.

The modulus of longitudinal elasticity of the first insulating layer 15 is preferably 1000 MPa or more and 5000 MPa or less. Furthermore, it is preferable that the modulus of elasticity is the same as that of the substrate and is lower than that of the first resin layer 11b and the second resin layer 12b. In the tactile sensor 100, the interface between the first resin layer 11b and the second resin layer 12b is displaced, and when the resin layer is deformed when the displacement occurs, the change in resistance value of the deformation becomes noise, and the measurement accuracy decreases. Therefore, it is preferable that the insulating layer has a modulus of elasticity lower than that of the first resin layer 11b and the second resin layer 12b. In addition, when shearing, the insulating layer is pressed in the thickness direction of the substrate before shearing, so it is preferable that the insulating layer has the same modulus of elasticity as the substrate so that the insulating layer does not deform in the thickness direction of the substrate. In addition, the insulating layer extends from the substrate in a columnar shape and is fixed only by the substrate. Therefore, during shearing, a force parallel to the substrate is applied to the end of the insulating layer. If the elastic modulus of the insulating layer is too high at this time, the insulating layer cannot deform when a shear force is applied and cannot release the force, so a large load is applied to the interface with the substrate, which is the fixed portion, and it may peel off from the substrate surface. For example, if the base material is polyimide, it is recommended that the base material be approximately 3000 MPa, the insulating layer be approximately 3000 MPa, and the resin layer be approximately 4000 MPa.

The second insulating layer 16 is provided on one side of the second substrate 2 and is formed using the same material and forming method as the first insulating layer 15. The second insulating layer 16 is formed in the same shape as the inner insulating layer 15a and the outer insulating layer 15b, and is provided between the inner insulating layer 15a and the outer insulating layer 15b at a position that bisects the distance d2. However, the positional relationship between the second insulating layer 16 and the inner insulating layer 15a and the outer insulating layer 15b is not limited to this. For example, by forming the second insulating layer 16 so that it is partially in contact with the inner insulating layer 15a, it is possible to suppress the shift in the contact direction and prevent erroneous detection. This is effective in cases where the shift direction is fixed, such as analysis of the shear force when lifting a heavy object.

The width and height (thickness) of the second insulating layer 16 are appropriately changed depending on the modulus of longitudinal elasticity of the material used. As an example, the width of the second insulating layer 16 can be 0.15 times or more and less than 0.5 times the amount of shear, preferably 0.15 times or more and 0.2 times or less. If the width is less than 0.15 times the amount of shear, it becomes difficult to form, and if it is 0.5 times or more, the amount of shear becomes small. In addition, the height of the second insulating layer 16 can be 0.05 to 0.1 times the width. If the height is designed to exceed 0.1 times the width, sagging and the like will occur, making it difficult to form. As an example, in a tactile sensor set to generate a shear amount of 0.5 mm when a shear force of 2 N is input, it is recommended to form it with a height of 0.01 mm and a width of 0.2 mm.

The thickness of the first insulating layer 15 and the second insulating layer 16 is not particularly limited, but it is desirable that they are thicker than the first resin layer 11b and the second resin layer 12b. By forming them thicker than each resin layer, when the first laminate 11 and the second laminate 12 are opposed to each other, the first insulating layer 15 and the second insulating layer 16 become the fulcrums, and the second base material 2 sags, so that the first resin layer 11b and the second resin layer 12b come into contact with each other. In this state, no extra stress acts on the first resin layer 11b and the second resin layer 12b, and it is possible to shift the first resin layer 11b and the second resin layer 12b by shear. The amount of sagging can be approximated as the deflection of a beam with the first insulating layer 15 and the second insulating layer 16 as the fulcrums, and varies depending on the thickness and hardness of the base material and the distance of the fulcrum. The amount of deflection D is expressed as follows, where L is the distance between the fixed ends, W is the load (the weight of the base material in this case), I is the second moment of area, and E is the modulus of longitudinal elasticity: D = WL^3/48EI
When the deflection amount D exceeds the thickness of the first insulating layer 15 and the second insulating layer 16, it means that the upper and lower base materials are in contact with each other.

The first insulating layer 15 and the second insulating layer 16 can be made of materials such as highly insulating and hard thermosetting resins, such as polyurethane resin, phenolic resin, epoxy resin, urea resin, melamine resin, and polyimide resin.

In the state where the first substrate 1 and the second substrate 1 shown in FIG. 1 are bonded together, the tactile sensor 100 may be further sealed with tape or the like to prevent the bonded substrates from coming apart.

Figure 4 is a cross-sectional view of the tactile sensor near the laminate when measuring shear force. More specifically, Figure 4(a) shows the state of the tactile sensor 100 when no shear force is applied, and Figure 4(b) shows the state of the tactile sensor 100 when a shear force is applied.

In the state of FIG. 4(a), the first electrode 11a and the second electrode 12a are shifted so that they overlap only partially in a plan view. When a shear force is input from the state of FIG. 4(a) to the right of the paper, the overlapping area between the first electrode 11a and the second electrode 12a increases, and the electrical resistance between the electrodes decreases. On the other hand, when a shear force is input to the left of the paper, the overlapping area between the first electrode 11a and the second electrode 12a decreases, and the electrical resistance between the electrodes increases. Therefore, the direction and magnitude of the shear force can be detected based on this change in resistance. Note that, if it is not necessary to detect the direction of the shear force, the initial positions of the first electrode 11a and the second electrode 12a may be set to a state in which the first electrode 11a and the second electrode 12a completely overlap.

The tactile sensor 100 may further include a fixing layer 17 made of double-sided tape, an adhesive layer, or the like, on the outside of the first insulating layer 15 and the second insulating layer 16 (FIG. 5). By providing the fixing layer 17, the positional relationship between the first substrate 1 and the second substrate 2 can be fixed, and any deviation between the first resin layer 11b and the second resin layer 12b caused by shear force is due to distortion of the substrate, not to the movement of the entire substrate. In this case, the distortion returns to normal when the shear force is removed, improving the reproducibility of signal detection compared to the case where the fixing layer 17 is not provided.

When the fixing layer 17 is provided, the fixing layer 17 has a thickness equal to or greater than the first insulating layer 15 and the second insulating layer 16. This is to prevent the fixing layer 17 from causing unnecessary stress to the substrate. The thickness of the fixing layer 17 is preferably 1.0 to 10 times the thickness of the first insulating layer 15 and the second insulating layer 16. If the fixing layer 17 is thinner than the first insulating layer 15 and the second insulating layer 16, stress is generated in the substrate, which inhibits misalignment. If the fixing layer 17 is made thicker than 10 times, the fixing layer 17 will be much thicker than the first laminate 11 and the second laminate 12, and therefore the fixing layer 17 will receive the force that should be applied to the first resin layer 11b and the second resin layer 12b during use, and the first resin layer 11b and the second resin layer 12b will not be subjected to sufficient force, resulting in detection failure. In addition, it is preferable that the distance from the second insulating layer 16 to the fixing layer 17 is twice the distance d1. If the distance between the fixing layer 17 and the second insulating layer 16 is less than twice the distance d1, the fixing layer 17 will cause stress to be generated in the substrate. Furthermore, if it exceeds two times, the parts of the tactile sensor 100 that are not involved in detection will increase, and the sensor will become larger.

As described above, the tactile sensor 100 according to this embodiment includes a first insulating layer 15 and a second insulating layer. As a result, when the opposing first laminate 11 and second laminate 12 are displaced due to shear, the first insulating layer 15 and the second insulating layer collide with each other to restrict the amount of displacement, thereby preventing damage to the sensor when displaced.

In addition, by providing the fixing layer 17, the upper and lower electrodes can easily return to their initial positions even after a shear force is applied, improving the reproducibility of the measurement.

Example 1
A 125 μm polyimide film (Toray: Kapton 500V) was used as the first substrate 1, and the first electrodes 11a shown in FIG. 2 were produced by printing within a range of 7 mm × 7 mm using silver paste. At this time, the first electrodes 11a were each produced in a U-shape, and the dimensions of the rectangular small electrodes were each 0.5 mm wide and 3.2 mm long, with a distance between the small electrodes of 2.5 mm. In addition, the leads were also 0.03 mm wide and arranged so as not to cross each other, at the same time as the first electrodes 11a.

Next, a carbon ink JELCON CH-N manufactured by Jujo Chemical was printed on each of the small electrodes of the first electrode 11a to form a first resin layer 11b, thereby producing the first laminate 11. The film thickness of the CH-N was 6 μm on average.

The first insulating layer 15 was made by forming an insulating resin FR-1T-NSD9 made by Asahi Chemical Laboratory into a square shape by screen printing so that the outer insulating layer 15b would be formed 250 μm away from each side from the 7 mm x 7 mm area including the first electrode 11a. At this time, the width was 150 μm, and the distance between the inner insulating layer 15a and the outer insulating layer 15b was 500 μm. The film thickness was also 15 μm.

A 125 μm polyimide film (Toray: Kapton 500V) was used as the second substrate 2, and the second electrode 12a and lead shown in FIG. 3 were produced by printing using silver paste.

Next, Jujo Chemical's carbon ink JELCON CH-N was printed on each of the small electrodes of the second electrode 12a to form the second resin layer 12b, producing the second laminate 12. The average thickness of the CH-N was 6 μm.

The second insulating layer 16 was produced by screen printing Asahi Chemical Laboratory's insulating resin FR-1T-NSD9 into a square shape so that it would be located between the inner insulating layer 15a and the outer insulating layer 15b when the first substrate 1 and the second substrate 2 were bonded together. At this time, the printed line width was 150 μm and the film thickness was 15 μm.

The first laminate 11 and the second laminate 12 were placed opposite each other, and a 50 μm-thick double-sided tape was placed between the first substrate 1 and the second substrate 2 to fix the substrates, thereby obtaining the tactile sensor 100 according to Example 1 (FIG. 5). At this time, the overlap width between the small electrodes of the first electrode 11a and the small electrodes of the second electrode 12a in a plan view was 250 μm. The fixing position was the outermost side of the substrate constituting the tactile sensor 100.

When a shear force was applied to this sensor with a finger, the base material shifted in the direction of the shear, and a corresponding change in the resistance value of the electrode was observed. When the shear force was continued, the resistance change also stopped when the base material stopped shifting.

(Comparative Example 1)
A 125 μm polyimide film (Toray: Kapton 500V) was used as the first substrate 1, and the first electrodes 11a shown in FIG. 2 were produced by printing within a range of 7 mm × 7 mm using silver paste. At this time, the first electrodes 11a were each produced in a U-shape, and the dimensions of the rectangular small electrodes were 0.5 mm wide and 3.2 mm long, and the distance between the small electrodes was 2.5 mm. In addition, the leads were also 0.03 mm wide and arranged so as not to cross each other, at the same time as the first electrodes 11a.

Next, a carbon ink JELCON CH-N manufactured by Jujo Chemical was printed on each of the small electrodes of the first electrode 11a to form a first resin layer 11b, thereby producing the first laminate 11. The film thickness of the CH-N was 6 μm on average.

A 125 μm polyimide film (Toray: Kapton 500V) was used as the second substrate 2, and the second electrode 12a and lead shown in FIG. 3 were produced by printing using silver paste.

Next, Jujo Chemical's carbon ink JELCON CH-N was printed on each of the small electrodes of the second electrode 12a to form the second resin layer 12b, producing the second laminate 12. The average thickness of the CH-N was 6 μm.

The first laminate 11 and the second laminate 12 were placed opposite each other, and a 10 μm-thick double-sided tape was placed between the first substrate 1 and the second substrate 2 to fix the substrates, thereby obtaining a tactile sensor according to Comparative Example 1. The fixing position was the outermost side of the substrate constituting the tactile sensor 100.

When a shearing force was applied to this sensor with a finger, the base material shifted in the direction of the shearing, and a change in the resistance value of the corresponding electrode was observed. However, when the shearing continued, no change in the resistance value was observed, even though the base material was shifting. Upon checking, it was found that the upper and lower detection layers were completely misaligned.

The present invention can be applied to pressure sensors that measure pressure and shear stress.

1 First substrate 2 Second substrate 11 First laminate 11X First laminate 11Y First laminate 11a: First electrode 11b First resin layer 12 Second laminate 12X Second laminate 12Y Second laminate 12a Second electrode 12b Second resin layer 15 First insulating layer 15a Inner insulating layer 15b Outer insulating layer 16 Second insulating layer 17 Fixing layer 100 Touch sensor d1: Distance d2: Distance

Claims (6)

A first substrate;
a first laminate provided on one surface of the first base material, in which a first electrode and a first resin layer having electrical conductivity are laminated in this order from the first base material side;
a first insulating layer provided on the one surface of the first base material so as to surround the first stack and to be spaced apart from the first stack;
a second base material facing the one surface of the first base material;
a second laminate provided on a surface of the second base material facing the first base material at a position facing the first laminate, the second laminate including, in this order from the second base material side, a second electrode and a second resin layer having electrical conductivity;
a second insulating layer provided on a surface of the second base material facing the first base material, the second insulating layer surrounding the second stack and spaced apart from the second stack;
a shear force applied can be detected based on a change in electrical resistance between the first electrode and the second electrode according to an overlapping area of the first resin layer and the second resin layer;
the first insulating layer includes an inner insulating layer surrounding the first laminate, and an outer insulating layer surrounding the inner insulating layer and spaced a predetermined distance from the inner insulating layer;
The second insulating layer is located between the inner insulating layer and the outer insulating layer. A shear force applied in a first direction can be detected using the first stack and the second stack,
The tactile sensor according to claim 1 , wherein the first electrode and the second electrode each have a pair of small electrodes extending in a second direction perpendicular to the first direction, and a connection portion that electrically connects the pair of small electrodes. Two of the first stacks and two of the second stacks,
2. The tactile sensor of claim 1, wherein a shear force in the first direction can be detected using one side of the first laminate and one side of the second laminate opposing it, and a shear force in a second direction perpendicular to the first direction can be detected using the other side of the first laminate and the other side of the second laminate opposing it. the first electrode of the first stacked body and the second electrode of the second stacked body each have a pair of small electrodes extending in the second direction and a connection portion electrically connecting the pair of small electrodes,
The tactile sensor according to claim 3 , wherein the other first electrode of the first laminate and the other second electrode of the second laminate have a pair of small electrodes extending in the first direction and a connection portion electrically connecting the pair of small electrodes. The tactile sensor according to claim 1, wherein the first resin layer and the second resin layer have a modulus of elasticity of 1000 MPa to 5000 MPa. The tactile sensor according to claim 1, wherein the first insulating layer and the second insulating layer have a modulus of elasticity of 1000 MPa to 5000 MPa.

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