WO2018056062A1

WO2018056062A1 - Stretchable capacitor, deformation sensor, displacement sensor, method for sensing respiration state, and sensing wear

Info

Publication number: WO2018056062A1
Application number: PCT/JP2017/032247
Authority: WO
Inventors: 翔太森本; 石丸　園子; 義哲権
Original assignee: 東洋紡株式会社
Priority date: 2016-09-21
Filing date: 2017-09-07
Publication date: 2018-03-29
Also published as: TWI799389B; TW201814749A; JPWO2018056062A1; JP7060847B2

Abstract

[Problem] To provide a stretchable capacitor that shows a 1:1 relationship between degree of stretching and capacitance and has high sensitivity and no hysteresis, and to apply the same to a respiration sensor or sensing wear. [Solution] Provided is a capacitor having a layered structure in which at least a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer are stacked in that order, wherein the stretchable capacitor is obtained by using: the stretchable conductor layers that are a composition containing metal particles and that is characterized in that the specific resistance when not stretched is 3 × 10⁻³ Ωcm or less and the specific resistance when 100% stretched is no greater than 100 times the specific resistance when not stretched; and a stretchable dielectric layer with little inorganic constituents, preferably with a Poisson ratio of at least 0.28. The obtained stretchable capacitor can be attached to a belt, shirt, or the like and is capable of sensing respiration on the basis of changes in a sleeveless garment. Moreover, if the stretchable capacitor is placed in an indirect location or the like of clothing, the motion of the wearer can be read.

Description

Elastic capacitor, deformation sensor, displacement sensor, breathing state sensing method and sensing wear

The present invention relates to a capacitor having an expansion / contraction characteristic, a capacitor whose capacitance changes due to expansion / contraction, a capacitor capable of reading expansion / contraction deformation by a change in capacitance, and a deformation sensor using an expansion / contraction capacitor.
Furthermore, the present invention relates to a displacement sensor using capacitance change, and further relates to a method for sensing a breathing state by measuring a circumference change of a human torso.
Furthermore, the present invention is a garment including a stretchable capacitor that can detect its own deformation as a change in capacitance, and when the subject is worn, the body changes due to a change in capacitance of the stretchable capacitor provided in the garment. The present invention relates to sensing wear that can detect shape change, that is, limb movement, body shape, posture, breathing, mastication, swallowing, pulsation, fetal movement and the like in a substantially non-invasive manner.

As an electrostatic capacitance type sensor, an object used for a surface pressure distribution sensor, a strain gauge, or the like that detects an uneven shape of a measurement object from a capacitance change between a pair of electrode layers is known.

Conventionally, as a capacitive sensor sheet used as a surface pressure distribution sensor, for example, it has a laminated structure in which an elastomeric dielectric layer is sandwiched between electrodes made of two conductive layers, and a load applied in a direction perpendicular to the surface. A surface pressure distribution sensor that captures the changing thickness of the dielectric layer as a capacitance change is known.
In Patent Document 1, two sheet-like dielectrics that are elastically deformable in all directions are overlapped with each other with one conductive cloth interposed therebetween, and two conductive cloths are provided on both sides of both sheet-like dielectrics. The two conductive cloths are ground layers and are electrically connected to each other, and each of the two sheet-like dielectrics has a plurality of through holes, and is opened in one sheet-like dielectric. There is disclosed a capacitive pressure sensor in which the position of the through hole formed in the other sheet-shaped dielectric and the through hole formed in the other sheet-shaped dielectric are different from each other.

Patent Document 2 discloses a dielectric layer made of a stretchable cloth, a front side coating layer made of an elastomer or a resin and laminated on the front side of the dielectric layer and stretchable integrally with the dielectric layer, and the front side coating. A front side adhesive layer which is interposed between the layer and the dielectric layer and adheres to the front side covering layer and the dielectric layer and can be stretched and contracted integrally with both layers, and is laminated on the back side of the dielectric layer. A backside coating layer that is integrally stretchable with the dielectric layer, and is interposed between the backside coating layer and the dielectric layer, and adheres to the backside coating layer and the dielectric layer to integrally stretch with both layers. A dielectric member having a possible back side adhesive layer, a front side electrode formed on a surface of the front side coating layer of the dielectric member and capable of extending and contracting integrally with the dielectric member, and a back surface of the back side coating layer of the dielectric member The back side electrode formed integrally with the dielectric member and expandable / contractible is opposed to the front and back direction. A capacitance unit comprising: a detection unit formed between the front electrode and the back electrode; and detecting an applied load based on a change in capacitance of the detection unit. A sensor is disclosed.

Further, Patent Document 3 includes a dielectric film made of an elastomer and a pair of electrodes disposed via the dielectric film, and is elastically bendable. And a conductive filler composed of a carbon material blended in the elastomer, and can be expanded and contracted according to deformation of the dielectric film, and the pair of electrodes includes the elastomer and the conductive filler A percolation curve representing the relationship between the blending amount of the conductive filler and the electrical resistance of the elastomer composition, the first inflection point at which the electrical resistance decreases and the insulator-conductor transition occurs. A blending amount of the conductive filler (critical volume fraction: φc) is 25 vol% or less, and at least one surface of the pair of electrodes has a restraining member that restrains elastic deformation of the surface. Are location, capacitive sensor and detects the deformation based on a change in the electrostatic capacity between the pair of electrodes, it is disclosed.

Each of the capacitance type sensors disclosed in Patent Documents 1 to 3 has a planar laminate structure, and changes in the direction perpendicular to the plane, that is, mainly changes in the thickness of the dielectric layer are capacitances. This type of sensor is perceived as a change in the sensor. These sensors detect pressures or relatively small displacements and cannot be used for the purpose of detecting large deformations.

On the other hand, Patent Document 4 includes a dielectric layer made of an elastomer composition, a front-side electrode layer laminated on the surface of the dielectric layer, and a back-side electrode layer laminated on the back surface of the dielectric layer, and the front-side electrode The layer and the back electrode layer are at least partially opposed to each other with the dielectric layer interposed therebetween, and a portion where the front electrode layer and the back electrode layer are opposed to each other with the dielectric layer interposed therebetween is defined as a detection unit. In the capacitive sensor sheet, the front electrode layer and the back electrode layer are made of a conductive composition containing carbon nanotubes, and the elastomer composition includes polyether polyol as a polyol component, A capacitive sensor sheet characterized by containing urethane rubber containing isocyanate as an isocyanate component is disclosed, and the capacitive sensor sheet is uniaxial. It has been shown that withstand tension elongation of 100% or more.

That is, the invention disclosed in Patent Document 4 is a sensor of a type that measures the deformation in the surface direction using the capacitance change, not the change in the thickness direction. Such a sensor, that is, a deformable capacitor, can cope with a much larger deformation than a conventional sensor that reads a change in the thickness direction, which is practically about several percent. In addition, it can be said that the capacitance type sensor is different from the conventional capacitance type sensor in that large deformation and large displacement can be detected.

On the other hand, various methods for monitoring the respiratory state during sleep have been proposed for the purpose of diagnosing sleep apnea syndrome.
Patent Document 5 discloses a breathing sensor that measures a breathing motion by wrapping a strain gauge attached to an elastic belt around a chest and measures the sleep posture together with a switch for detecting a sleeping posture. A method for monitoring the condition has been proposed.
Patent Document 6 discloses a transducer that is slidably engaged with an at least partially elastic belt and generates an electrical signal representing the magnitude of the force in response to a force applied at least indirectly from the belt. Methods have been proposed for monitoring respiratory status.
In Patent Document 7, a clothing having a front opening portion with a constant width between the left and right front bodies, and both ends of the belt-like breathing sensor are detachably attached to the left and right front bodies of the clothing. A breathing sensor wearing garment characterized by comprising an adherend is disclosed.
In Patent Document 8, an air mat is laid under the body of a lying subject, and a heart rate, respiratory rate, snoring, etc. are measured from pressure fluctuations inside the air mat to diagnose sleep apnea syndrome. It is disclosed.

Motion capture technology is developing in the video field. Optical motion capture technology is used for special filming of movies. A technique of optically capturing the state of the body and facial expression, converting it into data, and reflecting it in CG to move a human body model or the like in a virtual space has been put to practical use as a production technique for movies and the like. Such a technique requires a large-scale apparatus.
On the other hand, in order to detect a change in body shape and a state of movement, attempts have been made to incorporate various sensors into clothing for measurement.
Patent Documents 9 and 10 disclose a technique for obtaining a joint angle using a piezoelectric sensor. Since a strong force is required for the deformation of the piezoelectric element, the body feels a reaction force when the movement of the joint angle is large, which causes discomfort to the subject and restricts the exercise itself. There is a problem that proper sensing is not possible.
Patent Document 11 discloses a method for measuring an indirect bending angle using an electromagnetic induction sensor. However, such a sensor is easily affected by an external magnetic field, and information obtained is a time derivative of motion. In addition, it is unsuitable for constantly sensing the deformation state of the body.

Patent Document 12 discloses a method of sensing a joint angle using a bending capacitor whose capacitance changes according to the bending angle as a sensor. However, the capacitance change due to the bending angle is small, and it is difficult to ensure the accuracy. Further, in the case of such a sensing method, it is necessary to accurately match the sensor mounting position to the bending position. Sensing wear needs to be produced according to the body shape of the individual, and even if the subject is the same, if the wearing state of the sensing wear is misaligned, sensing becomes unstable.

Japanese Patent No. 4141426 Japanese Patent No. 5486258 Japanese Patent No. 5496446 JP 2015-200592 A Japanese Patent Laid-Open No. 7-75631 JP-A-8-299306 JP 1998-099299 A JP 2000-271103 A Japanese Patent No. 4855373 Japanese Patent No. 4427655 Japanese Patent Laid-Open No. 7-75630 JP2015-217127A

A capacitance sensor that detects such a large deformation requires sufficient room for deformation not only in the dielectric, but also in the electrode portion sandwiching the dielectric, and also in the wiring portion depending on the structure. If an elastic polymer material is used as the dielectric, it can sufficiently cope with deformation of about 100%, but there are rare electrodes or wiring materials that can maintain conductivity even when the same degree of deformation is applied.
A technique using a conductive composition containing carbon nanotubes has also been proposed, but the conductivity obtained by dispersing the carbon nanotubes is similar to that of a conductive composition using carbon filler, and is a general metal electrode. When compared with, the specific resistance is several thousand to several tens of thousands of times. That is, an electrode formed of a conductive composition containing carbon nanotubes has an electric resistance component in the electrode surface, and thus the capacitor itself needs to be handled in a distributed constant manner. Further, since the resistance component cannot be ignored when measuring the impedance including the capacitance, the linearity of the sensor output is low. In addition, a Schottky barrier is created at the connection surface between the electrode layer containing carbon nanotubes and general metal wiring, resulting in a non-linear response especially when the sensor is driven at a low voltage, limiting the use as a sensor. There was a problem such as coming out.

The method of placing a belt-shaped displacement sensor around the body's torso and breathing sensing from the change in circumference of the body has a feeling that the belt-like object restrains the body, so that the subject feels a sense of discomfort and feels natural sleep. It is difficult to obtain. In addition, depending on the posture of such a belt-like displacement sensor, a change in the peripheral length due to respiration may not be transmitted to the peripheral length detector, and accurate monitoring may not be possible.
The method of monitoring the breathing state by detecting pressure fluctuations caused by physical changes accompanying breathing and using the entire bed as a pressure sensor array increases the size of the device, resulting in higher costs and a more comfortable sleeping experience. If the futon is made thicker, the detection accuracy decreases.
In addition to these, methods of sensing the respiratory state by analyzing the moving image of the subject during sleep are known, but it is often difficult to detect the respiratory state depending on the shooting direction, and does not give the subject a sense of incongruity Therefore, it is necessary to take a picture in a dark environment, and it is often difficult to obtain an image of a quality required for analysis.

If these sensors are integrated into clothing, they can be used as sensing information for biological information. Biological information sensing wear is easy to wear, can be applied to subjects with slightly different body shapes, can be stably sensed even when the wearing state is slightly deviated, and is uncomfortable when worn A natural feeling of wearing is not required.

The present invention has been made in view of such circumstances, and its purpose is to have a high elongation rate that can withstand large deformation, excellent reliability when repeatedly deformed, and in measuring the amount of deformation. An object of the present invention is to provide a stretchable capacitor that has no hysteresis, has a wide range, and can obtain an output with good response.

It is another object of the present invention to provide a low-load displacement sensor using a stretchable capacitor and to provide a breathing sensing method that does not cause a subject to feel uncomfortable using the sensor.
Furthermore, the present invention provides sensing wear that can detect a change in the shape of the wearer's body, that is, movement, body shape, posture, breathing, mastication, swallowing, pulsation, fetal movement, etc. of the wearer by applying an elastic capacitor to the wear. The purpose is to provide.

That is, the present invention has the following configuration.
[1] A capacitor having at least a layer structure in which a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer are laminated in this order, wherein the stretchable conductor layer is a composition containing metal particles. A non-stretchable specific resistance is 3 × 10 ⁻³ Ωcm or less, and a 100% stretched specific resistance is within 100 times that of non-stretched.
[2] The stretchable dielectric layer contains an inorganic filler having a relative dielectric constant of 2.5 or more at no load and a relative dielectric constant of 5 or more in a proportion of 10% by mass or less. The elastic capacitor according to [1], which is characterized.
[3] The stretchable conductor layer is composed of a stretchable conductor composition containing at least metal particles and a flexible resin having a tensile modulus of elasticity of 1 MPa or more and 1000 MPa or less. The stretchable capacitor according to [1] or [2], which is 7 to 35% by mass with respect to the total of the functional resins.
[4] The stretchable capacitor according to any one of [1] to [3], wherein the stretchable dielectric layer has hot-melt adhesiveness.
[5] The stretchable capacitor according to any one of [1] to [4], wherein the stretchable dielectric layer has a moisture permeability of 4000 g / m 2 · 24 hr or less.
[6] The stretchable capacitor according to any one of [1] to [5], wherein the stretchable dielectric layer has a dielectric breakdown voltage of 1.0 kV or more.
[7] The stretchable capacitor according to any one of [1] to [6], wherein the stretchable dielectric layer has a multilayer structure having a layer having hot-melt adhesiveness on at least one surface.
[8] The stretchable capacitor according to any one of [1] to [7], wherein a stretch recovery rate when stretched 100% in a plane direction is 98% or more.
[9] The surface direction of the stretchable dielectric layer of the stretchable capacitor according to any one of [1] to [8] is arranged toward the deformation direction of the measurement target, and according to the stretch deformation of the measurement target. A deformation sensor that detects a deformation of a measurement object by detecting a change in capacitance of a changing elastic capacitor.
[10] The capacitance change of the stretchable capacitor that changes according to the stretch deformation of the measurement object is mainly caused by the stretch in the thickness direction of the stretchable dielectric layer accompanying the stretch in the surface direction of the stretchable dielectric layer. The deformation sensor according to claim 9, wherein the deformation sensor is a change in capacitance due to expansion and contraction.

[11] A displacement sensor comprising at least a belt-shaped base material made of a stretchable material and a stretchable capacitor that can be deformed in accordance with the expansion and contraction of the belt-shaped base material.
[12] The displacement sensor according to [11], wherein the elastic capacitor is deformed in the surface direction of the dielectric layer of the capacitor.
[13] The stretchable capacitor is a capacitor having a layer structure in which a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer are laminated in this order, and the specific resistance of the stretchable conductor layer is 1 ×. 10 ⁻³ Ωcm or less, and the stretchable dielectric layer is composed of a stretchable insulating polymer having a tensile yield elongation of 70% or more, according to [11] or [12] Displacement sensor.
[14] The displacement sensor according to any one of [11] to [13], wherein the stress at the time of 20% elongation of the displacement sensor in the belt length direction is 20 N or less.
[15] The displacement sensor according to any one of [11] to [14], wherein a portion including the elastic capacitor is 10% or more and 100% or less with respect to the entire length of the belt-like object.
[16] A respiration sensor characterized in that the displacement sensor according to any one of [11] to [15] is disposed around the torso of a human body, and a respiratory state is detected by measuring a change in the circumference of the torso. State sensing method.

That is, the present invention has the following configuration.
[17] A sensing ware comprising an elastic capacitor, an electric capacitor for connecting the elastic capacitor and a device for detecting the capacitance of the elastic capacitor.
[18] The capacitor having a layer structure in which the stretchable capacitor is laminated in the order of a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer, and the specific resistance of the stretchable conductor layer is 1 ×. [10] Sensing wear according to [17], characterized in that it is 10 ⁻³ Ωcm or less and the stretchable dielectric layer is made of a stretchable insulating polymer having a tensile yield elongation of 70% or more.
[19] The sensing ware according to [17] or [18], wherein the elastic capacitor is arranged so that the deformation of the elastic capacitor is in the direction of the wear.
[20] The sensing wear according to any one of [17] to [19], wherein a stress at the time of 20% elongation in the surface direction of the stretchable capacitor is 15 N / cm or less.
[21] It is clothing for the upper body of the human body, and the elastic capacitor is disposed at least in any of the elbow, upper arm, lower arm, shoulder, back, chest, abdomen, and flank The sensing ware according to any one of [17] to [20], which is characterized.
[22] A garment for the lower body of the human body, characterized in that the stretchable capacitor is disposed at least at any of the knee, ankle, thigh, shin, hip, and waist. [17] Sensing wear according to any one of [20].
[23] The configuration according to any one of [17] to [20], wherein the elastic capacitor is disposed in at least one portion of each joint of the wrist and fingers at least in a glove shape. Sensing wear.
[24] The configuration according to any one of [17] to [20], wherein the elastic capacitor is disposed in at least one portion of each joint of the ankle and toe. Sensing wear.

Further, the present invention preferably has the following configuration.
[31] The stretchable capacitor according to any one of [1] to [8], wherein the stretchable dielectric layer has a Poisson's ratio of 2.8 or more.
[32] The elastic capacitor layer of the elastic capacitor described in [31] is arranged so that the surface direction of the elastic dielectric layer is directed toward the deformation direction of the measurement target, and the elastic capacitor changes in accordance with the elastic deformation of the measurement target. A deformation sensor that detects deformation of a measurement object by detecting a change in capacitance.
[33] The deformation sensor according to any one of [9], [10], and [11], wherein the measurement object is partial expansion and contraction of clothes.

Further, the present invention preferably has the following configuration.
[34] The stretchable dielectric layer has a relative dielectric constant in an unloaded state of 3.5 or more and a content of an inorganic filler having a relative dielectric constant of 5 or more is 10% by mass or less. The displacement sensor according to any one of [12] to [15].
[35] The stretchable conductor layer is made of a stretchable conductor composition containing at least metal particles and a flexible resin having a tensile elastic modulus of 1 MPa to 1000 MPa, and the amount of the flexible resin is the same as that of the conductive particles. The displacement sensor according to any one of [12] to [15] and [34], which is 7 to 35% by mass with respect to the total of the functional resins.
[36] The displacement sensor according to any one of [12] to [15], [34], and [35], wherein the stretchable dielectric layer includes a material having hot-melt adhesiveness.
[37] The displacement sensor according to any one of [12] to [15] and [34] to [36], wherein the stretchable dielectric layer has a Poisson's ratio of 0.28 or more.

Since the stretchable capacitor of the present invention has a high elongation rate in the plane direction, it does not only deform in the thickness direction of the capacitor, but also deforms in the plane direction like a conventionally known capacitance type sensor. It can be suitably used for measuring the amount. In addition, the elastic capacitor of the present invention employs a dielectric layer having a good stretch recovery rate, so that the permanent strain after being greatly deformed is small, and residual strain is unlikely to occur even when repeatedly deformed (stretched). It becomes. As a result, the hysteresis between the deformation amount and the output value (capacitance) is small, excellent in responsiveness and responsiveness, and excellent in reliability (long-term reliability) when repeatedly used.

Since the stretchable capacitor of the present invention uses a low-resistance stretchable conductor for the electrode, the durability of the device is high, and even when the device becomes large, the impedance in the device becomes uniform, so a large-area device In this case, a sensor array with uniform sensitivity can be configured.
Since the elastic capacitor of the present invention can be made thin, an extremely lightweight sensor can be configured as a result. Furthermore, since the stretchable capacitor of the present invention can keep the stress during stretching low, it has high sensitivity and can reduce the influence on the measurement object. Specifically, even when used for the purpose of detecting deformation of the body surface as a wearable smart device, smart apparel, sensing wear, etc., measurement is possible without giving the subject a sense of incongruity. By using the present invention, it is possible to realize data conversion of movements of subjects (humans, animals, robots, etc.) such as motion capture, which conventionally requires a large-scale device including a television camera, with an extremely small device. Become.

In the present invention, the capacitance change of the elastic capacitor that changes according to the elastic deformation in the surface direction of the elastic capacitor is mainly due to the expansion and contraction of the elastic dielectric layer in the surface direction of the elastic dielectric layer. This is a change in capacitance due to a change in the thickness direction. In order to exhibit such characteristics, it is preferable that the material used for the stretchable dielectric layer has a high Poisson's ratio. The Poisson's ratio of the stretchable dielectric layer in the present invention is preferably 0.28 or more, more preferably 0.38 or more, and further preferably 0.48 or more. In order to increase the Poisson's ratio, it is better that the inorganic component contained in the stretchable dielectric layer is small.

FIG. 1 is a schematic diagram showing a basic configuration of a stretchable capacitor used in the present invention. FIG. 2 is a configuration diagram of a stretchable sheet with a hot melt layer used for producing a stretchable capacitor used in the present invention. FIG. 3 is a schematic diagram showing an example in which a stretchable capacitor is configured by stacking a stretchable sheet on a base material. FIG. 4 is a schematic view showing the configuration of the stretchable capacitor used in the present invention. FIG. 5 is a process schematic diagram in the case of producing the stretchable capacitor used in the present invention by a printing method. FIG. 6 is a schematic diagram for explaining the extension recovery rate of the present invention. FIG. 7 is an example of a result of measuring the chest circumference change due to respiration by the displacement sensor using the elastic capacitor of the present invention. FIG. 8 is a process schematic diagram in the case of producing the stretchable capacitor used in the present invention by a printing transfer method. FIG. 9 is a schematic diagram for explaining the SS curve and the tensile yield elongation.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the stretchable capacitor of the present invention has the following basic structure. 1. Stretchable conductor layer (surface electrode) 2. stretchable dielectric layer; It has three layers of stretchable conductor layers (back electrode). In an actual configuration, an adhesive layer for adhering each layer may be inserted into each basic component layer. Furthermore, an insulating coating layer may be provided outside the stretchable conductor layer that is the outermost layer. As is obvious from the object of the present invention, the adhesive layer and the coating layer are also required to have sufficient stretch properties.

The specific resistance of the stretchable conductor layer in the present invention when not stretched is preferably 3 × 10 ⁻³ Ωcm or less, more preferably 1 × 10 ⁻³ Ωcm or less, and 3 × 10 ⁻⁴ Ωcm or less. It is preferably 1 × 10 ⁻⁴ Ωcm or less. When the specific resistance exceeds this range, the resistance distribution in the conductive layer becomes remarkable, the time constant of the element becomes large, causing a problem in response, and the high frequency characteristics and pulse response may be deteriorated. The lower limit of the specific resistance depends on the conductive material used in principle.

In the stretchable conductor layer of the present invention, the specific resistance at 100% elongation is preferably within 100 times that at non-stretching, more preferably within 50 times, and further preferably within 30 times, 15 It is more preferable that it is within the range. If the specific resistance at 100% elongation exceeds this range, the resistance distribution in the conductive layer becomes noticeable, the time constant of the element increases, causing a problem in response, and high-frequency characteristics and pulse response are reduced. There is. The lower limit of the specific resistance depends on the conductive material used in principle. Note that when the stretchable conductor is deformed, a geometric change accompanying the deformation, that is, a change in resistance value due to a change in length and cross-sectional area in the current direction is excluded. Within the range of the initial specific resistance in the present invention and the specific resistance at the time of expansion, the resistance distribution in the conductive layer can be kept sufficiently small even if a change in the resistance value due to geometric deformation is added. it can. *

The stretchable conductor layer in the present invention is composed of at least metal particles and a flexible resin having a tensile elastic modulus of 1 MPa to 1000 MPa. The blending amount of the flexible resin is 7 to 35% by mass with respect to the total of the conductive particles and the flexible resin.
The stretchable conductor layer in the present invention can be obtained by kneading and mixing metal particles and a flexible resin and molding the film into a sheet or sheet. The stretchable conductor layer of the present invention is preferably processed into a sheet or film form by coating and drying after adding a solvent to the metal particles and the flexible resin to form a stretchable conductor forming paste or slurry. I can do it. Moreover, a predetermined shape can also be given by printing after paste-izing.

The metal particles in the present invention function as conductive particles. In the present invention, the conductive particles include the metal particles, are made of a substance having a specific resistance of 1 × 10 ⁻¹ Ωcm or less, and have a particle diameter of 100 μm or less. Examples of the substance having a specific resistance of 1 × 10 ⁻¹ Ωcm or less include metals, alloys, carbon, doped semiconductors, conductive polymers, and the like. The conductive particles preferably used in the present invention are metals such as silver, gold, platinum, palladium, copper, nickel, aluminum, zinc, lead and tin, alloy particles such as brass, bronze, white copper and solder, and silver-coated copper. Hybrid particles, metal-plated polymer particles, metal-plated glass particles, metal-coated ceramic particles, and the like can be used.

In the present invention, it is preferable to mainly use flaky silver particles or amorphous aggregated silver powder as metal particles. Here, the main use is to use 90% by mass or more of the conductive particles. The amorphous aggregated powder is a three-dimensional aggregate of spherical or irregularly shaped primary particles. Amorphous agglomerated powders and flaky powders are preferable because they have a specific surface area larger than that of spherical powders and the like and can form a conductive nitrate work even with a low filling amount. Since the amorphous agglomerated powder is not in a monodispersed form, the particles are in physical contact with each other, so that it is easy to form a conductive nitrate work.

The particle size of the flaky powder is not particularly limited, but those having an average particle size (50% D) measured by a dynamic light scattering method of 0.5 to 20 μm are preferable. More preferably, it is 3 to 12 μm. When the average particle diameter exceeds 15 μm, it becomes difficult to form fine wiring, and clogging occurs in the case of screen printing. When the average particle size is less than 0.5 μm, it is impossible to make contact between particles at low filling, and the conductivity may deteriorate.

The particle size of the amorphous aggregated powder is not particularly limited, but those having an average particle size (50% D) measured by a light scattering method of 1 to 20 μm are preferable. More preferably, it is 3 to 12 μm. When the average particle diameter exceeds 20 μm, the dispersibility is lowered and it becomes difficult to form a paste. When the average particle size is less than 1 μm, the effect as an agglomerated powder is lost, and good conductivity may not be maintained with low filling.

In the present invention, non-conductive particles may be blended in the stretchable conductor layer as necessary. The non-conductive particles in the present invention are particles made of an organic or inorganic insulating substance. The non-conductive particles in the present invention are added for the purpose of improving printing characteristics, stretching properties, and coating surface properties, and are composed of inorganic particles such as silica, titanium oxide, talc, alumina, barium sulfate, and resin materials. A microgel or the like can be used.

Examples of the flexible resin in the present invention include a thermoplastic resin, a thermosetting resin, and a rubber having an elastic modulus of 1 to 1000 MPa. In order to exhibit the stretchability of the film, urethane resin or rubber is preferable. Rubbers include urethane rubber, acrylic rubber, silicone rubber, butadiene rubber, nitrile group-containing rubber such as nitrile rubber and hydrogenated nitrile rubber, isoprene rubber, sulfurized rubber, styrene-butadiene rubber, butyl rubber, chlorosulfonated polyethylene rubber, ethylene Examples include propylene rubber and vinylidene fluoride copolymer. Among these, nitrile group-containing rubber, chloroprene rubber, and chlorosulfonated polyethylene rubber are preferable, and nitrile group-containing rubber is particularly preferable. In the present invention, the range of elastic modulus is preferably 2 to 480 MPa, more preferably 3 to 240 MPa, and still more preferably 4 to 120 MPa.

The rubber containing a nitrile group is not particularly limited as long as it is a rubber or elastomer containing a nitrile group, but nitrile rubber and hydrogenated nitrile rubber are preferable. Nitrile rubber is a copolymer of butadiene and acrylonitrile. If the amount of bound acrylonitrile is large, the affinity with metal increases, but the rubber elasticity contributing to stretchability decreases conversely. Accordingly, the amount of bound acrylonitrile in the acrylonitrile butadiene copolymer rubber is preferably 18 to 50% by mass, and particularly preferably 40 to 50% by mass.

The blending amount of the flexible resin in the present invention is 7 to 35% by mass, preferably 9 to 28% by mass, more preferably based on the total of the conductive particles, preferably the non-conductive particles and the flexible resin to be added. Is 12 to 20% by mass.

Also, an epoxy resin can be blended in the stretchable conductor forming paste in the present invention. A preferable epoxy resin in the present invention is a bisphenol A type epoxy resin or a phenol novolac type epoxy resin. When blending an epoxy resin, an epoxy resin curing agent can be blended. A known amine compound, polyamine compound, or the like may be used as the curing agent. The curing agent is preferably blended in an amount of 5 to 50% by weight, more preferably 10 to 30% by weight, based on the epoxy resin. The blending amount of the epoxy resin and the curing agent is 3 to 40% by mass, preferably 5 to 30% by mass, and more preferably 8 to 24% by mass with respect to the total resin components including the flexible resin.

The paste for forming a stretchable conductor in the present invention contains a solvent. The solvent in the present invention is water or an organic solvent. Since the content of the solvent should be appropriately investigated depending on the viscosity required for the paste, it is not particularly limited, but is generally preferably 30 to 80 mass ratio when the total mass of the conductive particles and the flexible resin is 100. The organic solvent used in the present invention preferably has a boiling point of 100 ° C. or higher and lower than 300 ° C., more preferably 130 ° C. or higher and lower than 280 ° C. If the boiling point of the organic solvent is too low, the solvent volatilizes during the paste manufacturing process or use of the paste, and there is a concern that the component ratio of the conductive paste is likely to change. On the other hand, if the boiling point of the organic solvent is too high, the amount of residual solvent in the dry cured coating film increases, and there is a concern that the reliability of the coating film is reduced.

Examples of the organic solvent in the present invention include cyclohexanone, toluene, xylene, isophorone, γ-butyrolactone, benzyl alcohol,

Exxon Chemical Solvesso

100, 150, 200, propylene glycol monomethyl ether acetate, terpionol, butyl glycol acetate, diamylbenzene. , Triamylbenzene, n-dodecanol, diethylene glycol, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol dibutyl ether, diethylene glycol monoacetate, triethylene glycol diacetate, triethylene glycol, triethylene glycol Monomethylether , Triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, tetraethylene glycol, tetraethylene glycol monobutyl ether, tripropylene glycol, tripropylene glycol monomethyl ether, 2,2,4-trimethyl-1,3-pentanediol monoiso Examples include butyrate. As petroleum-based hydrocarbons, AF Solvent No. 4 (boiling point: 240 to 265 ° C.), No. 5 (boiling point: 275 to 306 ° C.), No. 6 (boiling point: 296 to 317 ° C.) manufactured by Nippon Oil Corporation No. 7, (boiling point: 259-282 ° C.), and No. 0 solvent H (boiling point: 245-265 ° C.), etc., and two or more of them may be included if necessary. Such an organic solvent is appropriately contained so that the stretchable conductor-forming paste has a viscosity suitable for printing or the like.

The paste for forming a stretchable conductor in the present invention is a dispersing machine such as conductive particles, barium sulfate particles, stretchable resin, solvent, dissolver, three roll mill, self-revolving mixer, attritor, ball mill, sand mill, etc. Can be obtained by mixing and dispersing.

The paste for forming a stretchable conductor in the present invention is provided with known organic and inorganic additives such as imparting printability, color tone adjustment, leveling, antioxidants, ultraviolet absorbers and the like within the scope of the invention. Can be blended.

In the present invention, the stretchable dielectric layer is made of a stretchable resin material, that is, a polymer material. Examples of the flexible polymer material include elastomers, thermoplastic resins, thermosetting resins, and rubbers having an elastic modulus of 1 to 1000 MPa. In order to exhibit the stretchability of the film, urethane resin or rubber is preferable. Rubbers include urethane rubber, acrylic rubber, silicone rubber, butadiene rubber, nitrile group-containing rubber such as nitrile rubber and hydrogenated nitrile rubber, isoprene rubber, sulfurized rubber, styrene-butadiene rubber, butyl rubber, chlorosulfonated polyethylene rubber, ethylene Examples include propylene rubber and vinylidene fluoride copolymer. Among these, nitrile group-containing rubber, chloroprene rubber, and chlorosulfonated polyethylene rubber are preferable, and nitrile group-containing rubber is particularly preferable. In the present invention, the elastic modulus is preferably in the range of 1.2 to 420 MPa, more preferably 1.4 to 210 MPa, and still more preferably 1.5 to 150 MPa.

Examples of the flexible polymer material preferably used in the present invention include urethane rubber having polyether polyol or polyester polyol as a polyol component and HDI polyisocyanate as an isocyanate component.
The urethane rubber in the present invention is a stretchable dielectric layer that has a high elongation rate and is excellent in reliability when repeatedly deformed because the tensile permanent strain and residual strain are small.

Examples of the polyether polyol in the present invention include copolymerization of monomer materials such as polyethylene glycol, polypropylene glycol, polypropylene triol, polypropylene tetraol, polytetramethylene glycol, polytetramethylene triol, and cyclic ether for synthesizing these. Examples thereof include polyalkylene glycols such as copolymers, derivatives obtained by introducing side chains or branched structures, modified products, and mixtures thereof. Of these, polytetramethylene glycol is preferred. The reason is that the mechanical properties are excellent.

Commercially available products can also be used as the polyether polyol. Specific examples of commercially available products include PTG-2000SN (Hodogaya Chemical Co., Ltd.), polypropylene glycol, Preminol S3003 (Asahi Glass Co., Ltd.), Pandex GCB-41 (DIC Corporation), and the like.

As the polyester polyol in the present invention, aromatic polyester polyol, aromatic / aliphatic copolymer polyester polyol, aliphatic polyester polyol, and alicyclic polyester polyol can be used. As the polyester polyol in the present invention, either a saturated type or an unsaturated type may be used.

The HDI polyisocyanate in the present invention is hexamethylene diisocyanate (HDI) or a modified product thereof, and is a compound having a plurality of isocyanate groups in the molecule.

The urethane rubber in the present invention may be obtained by reacting a mixture containing a chain extender, a crosslinking agent, a catalyst, a vulcanization accelerator, etc., as necessary, in addition to the polyol component and the isocyanate component. good. In the present invention, it is preferable to use a sulfur-free crosslinking agent. The flexible polymer material in the present invention may contain additives such as plasticizers, antioxidants, anti-aging agents, colorants, dielectric fillers, and the like.
The average thickness of the dielectric layer in the present invention is 0.3 to 1000 μm from the viewpoint of improving the detection sensitivity by increasing the capacitance C and improving the followability to the measurement object. In view of sensitivity, the range is preferably 0.3 to 20 μm, more preferably 0.3 to 8 μm, and further preferably 0.5 to 6 μm.

The relative dielectric constant of the stretchable dielectric layer in the present invention at no load is 2.5 or more, preferably 2.8 or more, more preferably 3.3 or more, and still more preferably 3.6 or more. The upper limit of the relative dielectric constant is about 7.0, preferably 5.6 or less, more preferably 4.8 or less. For the purpose of the present invention, it is preferable that the dielectric constant of the stretchable dielectric layer is high, but in general, a polymer material having stretchability often has an alkyl group in the flexible chain component, and a relatively low ratio. It has a dielectric constant. In the present invention, it is preferable to increase the relative dielectric constant by introducing a polar group into the molecular chain. A nitrile group, a ketone group, an ester group, a halogen substituent, a hydroxyl group, a carboxyl group, a nitro group, etc. It is an effective functional group for increasing the rate.

It is possible to increase the dielectric constant of the dielectric layer by adding a filler having a high dielectric constant, preferably an inorganic filler such as titanate. However, in the present invention, the content of the inorganic filler having a relative dielectric constant of 5 or more in the stretchable dielectric layer is preferably 10% by mass or less. The content of the inorganic filler is preferably 3% or less, more preferably 1% or less, still more preferably 0.3% or less. If the content of the inorganic filler is large, when the stretchable dielectric layer is stretched or compressed, the stress concentration on the stretchable polymer part becomes high, and peeling occurs at the filler and resin interface, forming voids. In some cases, there is a problem in durability.
Moreover, when there are many inorganic fillers contained in a stretchable dielectric layer, the Poisson's ratio of the stretchable dielectric layer becomes low, the capacitance change during stretching becomes small, and the sensitivity when applied as a sensor is lowered.

Stretch dielectric layer of the present invention, moisture permeability is preferably from 4000g ^/ m 2 · 24hr, further preferably less ^{2500g / m 2 · 24hr, 1000g} / m 2 · 24hr or less is still preferred. When the moisture permeability of the stretchable dielectric layer is high, there is a possibility that the capacitance value indicated by the stretchable capacitor changes depending on the dry-wet state.

The dielectric breakdown voltage of the stretchable dielectric layer of the present invention is preferably 1.0 kV or higher, more preferably 1.5 kV or higher, still more preferably 2.0 kV or higher. When the dielectric breakdown voltage is low, there is a risk that the elastic capacitor will be short-circuited and damaged when a high voltage is applied.

In the present invention, the stretchable dielectric layer preferably has hot melt properties. When the stretchable dielectric layer has hot melt properties, the stretchable conductor layer and the stretchable dielectric layer can be easily laminated by a technique such as hot pressing or roll lamination.

A commercially available flexible resin sheet can be used as the stretchable dielectric layer in the present invention. Examples of commercially available flexible resin sheets include a polyurethane film with a hot melt layer manufactured by Nisshinbo Co., Ltd .: Mobilon film MF103F3 (thickness 100 μm, having a hot melt layer on one side), a polyurethane film manufactured by Nisshinbo Co., Ltd .: Mobilon film MOB100S (thickness) 100 μm), Osaka Organic Chemical Co., Ltd. flexible acrylic resin film Suave-08 (thickness 300 μm), Nikkan Kogyo NS sheet (thickness 40 μm), DINGZING polyurethane film: Proveta FS1123 (thickness 50 μm), etc. It can be illustrated.

In the present invention, a hot melt adhesive may be used when laminating the stretchable conductor layer and the stretchable dielectric layer. As the hot-melt adhesive in the present invention, a polymer material having a softening temperature of about 30 ° C. to 150 ° C. can be used, and preferably has a flexibility having the same degree of elasticity as the dielectric layer. The provided polymeric material can be used. Such hot melt adhesives include ethylene copolymers, styrene block copolymers, and olefinic (co) polymers that contain crystalline polar groups to provide tackiness using them as a base polymer. Compound materials such as compounds, amorphous poly α-olefins, tackifying resins, polypropylene waxes, styrene-ethylenepropylene-styrene block copolymer rubbers or styrene-butadiene-styrene block copolymer rubbers, and more Polymer materials obtained by adding a tackifier resin component and / or a liquid plasticizer such as process oil, modified polyolefins and blends thereof, styrenic block copolymers and blends thereof, acid-modified polypropylene, and acid-modified styrene block copolymers Polymers, their blends, Styrene-based block copolymer, blends of such ethylene polymer, and the like can be used polyester urethane copolymers and blends thereof.
When a stretchable conductor layer and a stretchable dielectric layer are laminated using a hot melt adhesive, a hotmelt layer is preferably provided on at least one side of the stretchable dielectric layer, and preferably on both sides of the stretchable dielectric layer. It is preferable to arrange the layers. The hot melt layer can be used as an independent layer or previously laminated on one or both sides of a stretchable conductor layer or a stretchable dielectric layer.

In the present invention, a hot melt sheet obtained by processing a polyester urethane resin or a polyether urethane resin having a softening temperature of 40 ° C. to 120 ° C. into a sheet shape can be preferably used.

Hereinafter, the stretchable capacitor of the present invention will be described with reference to the drawings. FIG. 1 shows the basic configuration of the stretchable capacitor of the present invention. That is, in the present invention, the stretchable capacitor has a structure in which a stretchable dielectric layer is sandwiched between upper and lower stretchable conductive layers.

In the present invention, as a means for realizing such a stretchable capacitor, a method of laminating two sheets can be exemplified. That is, first, as shown in FIG. 2, a laminated sheet in which a stretchable conductor layer, a stretchable dielectric layer, and an adhesive layer are laminated is prepared. The stretchable conductor layer and the stretchable dielectric layer can be laminated by melt extrusion molding or by coating a paste material. A sheet of stretchable conductor layer and a sheet of stretchable dielectric layer can be prepared separately and bonded together with an adhesive layer. In this case, when an insulating adhesive is used as the adhesive layer, the adhesive layer becomes a part of the dielectric layer. Further, when an adhesive layer having conductivity is used, the adhesive layer becomes a part of the conductive layer. The adhesive layer preferably has the same stretchability and flexibility as the stretchable conductor layer and the stretchable dielectric layer.
As the adhesive layer, it is preferable to use an insulating hot-melt polymer material. In the present invention, first, stretchable conductivity is formed on the release sheet, then a stretchable dielectric layer is formed, and a hot melt adhesive sheet is further stacked, sandwiched between the release sheets, and heated and pressurized, Such a laminated sheet can be obtained.

Subsequently, as shown in FIG. 3, the laminated sheet of FIG. 2 is laminated on a stretchable fabric having high elongation using a hot melt layer, and the same laminated sheet is used as an electrode on the laminated sheet. However, the hot-melt adhesive layer sandwiched between the conductor layers and the stretchable capacitor in which the stretchable dielectric layer acts as a dielectric by shifting it so that it is exposed or cutting it into a predetermined pattern and pasting them together Can be obtained. A stretchable insulating cover layer can also be provided on the outermost conductor layer. As the insulating cover layer, an insulating resin similar to the polymer material used for the dielectric layer can be used. Such an insulating resin sheet can also be laminated through a hot melt adhesive layer.

Figure 4. FIG. 4 is a schematic view illustrating another embodiment of the stretchable capacitor of the present invention. The electrode of the elastic capacitor is connected to the terminal on the back surface of the base material through a through hole. As the through hole, a plated through hole used in a general printed wiring board or a through hole connected by a conductive paste or the like can be used. Further, a classic method of electrically connecting the front and back with a metal rivet or the like and fixing with caulking or the like can be applied. When the stretchable capacitor of the present invention is applied to clothes, a metal snap hook or the like may be used instead of the through-hole as in the case of a metal rivet.

As another aspect of the present invention, an elastic capacitor using a printing method can be exemplified. That is, a stretchable capacitor can be obtained by sequentially printing and laminating each layer in the order of A to F shown in FIG. Although FIG. 5 illustrates the step of printing directly on the base material sequentially, it is also possible to use a method of printing on a release film or the like in the reverse order and finally transferring to a fabric.

The stretch recovery rate in the present invention means that the initial length is L0, 20% when an elastic capacitor is suspended, stretched by applying a load, and contracted by removing the load as shown in FIG. Or when the length when stretched by a predetermined percentage is L1, and the length when the stretch load is removed is L2,
(Equation 1)
Elongation recovery rate = ((L1-L2) / (L1-L0)) × 100 [%]
(Equation 2)
Residual strain rate = ((L2-L0) / L0) × 100 [%]
L0 Initial length L3 Elongation = L1-L0
L4 recovery length = L1-L2
L5 Residual strain = L2-L0
And define. A similar measurement method is defined in the JIS L 1096 woven and knitted fabric test method, but not the recovery rate after stretching under a constant load, but the recovery rate when stretched to a certain length. Different. In actual use, the load applied to the stretchable conductor layer is often repeatedly stretched to a predetermined length regardless of the load, so that the practical performance cannot be expressed by the stretch recovery rate by the constant load method. The stretch recovery rate of the stretchable capacitor of the present invention is an evaluation of a portion that functions as a capacitor element, and the electrode portion is omitted. Unless otherwise noted, the elongation recovery rate is evaluated in an environment of 25 ° C. ± 3 ° C.

In the present invention, the capacitance direction of the elastic capacitor is arranged so that the surface direction of the elastic dielectric layer of the elastic capacitor described above is directed toward the deformation direction of the measurement object, and changes according to the elastic deformation of the measurement object. By detecting a change, it can be used as a deformation sensor for detecting the deformation of the measurement object.

In the present invention, the capacitance change of the elastic capacitor that changes according to the elastic deformation in the surface direction of the elastic capacitor is mainly due to the expansion and contraction of the elastic dielectric layer in the surface direction of the elastic dielectric layer. This is a change in capacitance due to a change in the thickness direction. In order to express such characteristics, it is preferable that the material used for the stretchable dielectric layer has a high Poisson's ratio. The Poisson's ratio of the stretchable dielectric layer of the present invention is preferably 0.28 or more, more preferably 0.38 or more, and further preferably 0.48 or more. In order to increase the Poisson's ratio, it is better that the inorganic component contained in the stretchable dielectric layer is small.
Here, the plane direction refers to a direction substantially perpendicular to the thickness direction. In the orthogonal coordinate system, generally, the XY axis direction is the plane direction, and the Z axis direction is the thickness direction. Since the stretchable capacitor of the present invention has flexibility, it can be used in a curved state. In this case, the surface direction indicates a direction substantially along the curved surface, and does not indicate the XYZ direction of the orthogonal coordinate system fixed rigidly.

In the present invention, the surface direction of the elastic dielectric layer of the elastic capacitor described above is laminated with a belt-like material made of an elastic material so that the elastic capacitor also expands and contracts according to the expansion and contraction of the belt-like material. By arranging in, the elongation of the belt-like material is read from the change in the capacitance of the elastic capacitor.

The belt-like material made of a stretchable material in the present invention is not particularly limited in material and structure, and is a belt-like material made of rubber or elastomer, a belt-like material having a knitted structure, or a belt-like material having a woven fabric structure. A belt-like object having a braid structure, a belt-like object having a cut paper structure, a belt-like object having a spiral structure, and a belt structure using a metal spring together.
The belt in the present invention refers to a flat and long structure. The length of the belt varies depending on the object to be measured, but when used for measuring the change in the circumference of the human body, a length range of about 300 mm to 2000 mm is preferable. The width of the belt is 3 mm or more and 150 mm or less, preferably 6 mm or more and 60 mm or less, depending on the handling surface and tactile feel. The thickness of the belt is not particularly limited, but is less than 5 mm, preferably less than 3 mm, more preferably less than 1 mm because the thinner one is less uncomfortable to the body.

In the present invention, the stretchable capacitor is preferably laminated so as to have a length of 3 to 100% with respect to the length direction of the belt-like material. In particular, by laminating over a length of 50% or more, preferably 70% or more, it becomes possible to provide a sensing unit over the entire circumference of the body when measuring the body circumference, and go to bed. The trouble that the sensing becomes unstable depending on the posture at the time can be avoided.
In actual use, it is preferable to provide the belt with a length adjusting portion for mounting on the body, a buckle portion for connecting the belt that has made one round in a ring shape, and the like. Since the stretchable capacitor of the present invention has a low stress at the time of extension, even when it is configured in a ring shape having a predetermined circumference, it can sufficiently absorb individual differences in circumference. In this case, the elastic capacitor can be installed substantially 100% of the belt-like material.

The stress when the displacement sensor of the present invention is stretched by 20% is preferably 20 N or less. Furthermore, in the present invention, the stress when the displacement sensor is stretched by 20% is preferably 12 N or less, more preferably 8 N or less, still more preferably 5 N or less, and even more preferably 3 N or less. When the stress is higher than this, a sense of incongruity increases when worn on the body.
In the present invention, the lower limit of the stress when the displacement sensor is extended is 0.5N, preferably 0.8N. If the stress is smaller than this, the fitting of the displacement sensor to the body becomes unsatisfactory, and depending on the posture, the measurement becomes unstable or the sensor position is likely to shift.

The sensing wear in the present invention is a clothing or garment for measuring biological information, and is not particularly limited as long as it is a clothing made of a belt-like object such as a belt or a bra and / or a knitted fabric or a nonwoven fabric. Sensing wear forms include shirts, trainers, pants, trousers, tights, or socks, gloves, hats, collars, bangles, upper and lower jumpsuits worn throughout the body, body suits, leotards, and whole body tights. It can take various forms.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples. In addition, the numerical value of the Example was measured by the method shown below.

<Nitrile amount>
From the composition ratio obtained by NMR analysis of the obtained resin material, it was converted to mass% based on the mass ratio of the monomers.

<Mooney viscosity>
This was measured using an SMV-300RT “Mooney Viscometer” manufactured by Shimadzu Corporation.

<Elastic modulus>
The sample to be measured was formed into a sheet shape with an arbitrary thickness in the range of 20 μm to 200 μm, and then punched into a dumbbell shape defined by ISO 527-2-1A to obtain a test piece.
A tensile test was performed by a method defined in ISO 527-1 to obtain a stress-strain diagram of the resin material, and an elastic modulus was calculated by a conventional method.

<Tensile yield elongation>
The sample to be measured was formed into a sheet shape with an arbitrary thickness in the range of 20 μm to 200 μm, and then punched into a dumbbell shape defined by ISO 527-2-1A to obtain a test piece. Next, the SS curve was obtained using a tensile tester, the yield point was obtained as shown in FIG. 9, and the elongation at that time was defined as the tensile yield elongation.
<Poisson's ratio>
The Poisson's ratio of the stretchable dielectric was determined by a method based on ISO 527-1: 2012.

<Glass transition temperature>
The glass transition temperature was determined by differential scanning calorimetry (DSC) according to a conventional method.

<Molecular weight>
A sample of the binder resin material was added to THF (tetrahydrofuran) so that the concentration of the resin in the solution was 0.4 mass%, stirred at room temperature for 1 hour, and then allowed to stand for 24 hours. Next, the resulting resin solution was diluted 4 times with THF, and then passed through a 0.45 μm filter. The filtrate was subjected to GPC to obtain a number average molecular weight, a weight average molecular weight, and a dispersion ratio (Mw / Mn). Asked.

<Extension recovery rate>
The sample to be measured was formed into a sheet shape with an arbitrary thickness in the range of 20 μm to 200 μm, and then punched into a dumbbell shape defined by ISO 527-2-1A to obtain a test piece.
Next, a mark was placed at a location 33 mm (effective length 66 mm) from the center of the 10 mm wide and 80 mm long portion in the dumbbell-shaped test piece, and the initial distance L0 between the marks was measured accurately. Next, the outside of the marked part is clamped, and the 66 mm mark is stretched to an extension length of 79.2 mm (+13.2 mm, corresponding to an extension degree of 20%), then separated from the clamp, and a predetermined temperature (especially When there was no notice, it put on the fluororesin sheet | seat hold | maintained horizontally at 25 degreeC), measured the distance L2 after the expansion | extension between marks, and calculated | required the expansion | restoration recovery rate according to the following formula | equation.
Initial length L0 = 66.0mm
Extension length L1 = 79.2mm
Length after extension L2 = Measured Elongation L3 = L1-L0 = 13.2 mm
Recovery length L4 = L1-L2
Elongation recovery rate = ((L1-L2) / (L1-L0)) × 100 [%]

<Stretch recovery rate of fabric>
The fabric material was punched into a dumbbell shape specified by ISO 527-2-1A to obtain a test piece. In addition, the extending | stretching direction of the fabric was made into the length direction of a dumbbell.
Next, as in the measurement of the stretch recovery rate of the resin, marks are placed at 33 mm positions (effective length 66 mm) from the center of the 10 mm width and 80 mm length in the dumbbell-shaped test piece, and the stretch length is 99 mm (+33 mm). The elongation recovery rate was determined by operating in the same manner as the resin stretch recovery rate except that the elongation was extended to 50%.

<Heat resistance of fabric>
The heat shrinkage temperature obtained by JIS L1013: 2010 chemical fiber filament yarn test method 8.19.2 was defined as the heat resistance of the fabric.

<Average particle size>
The average particle size of the filler was measured using a light scattering type particle size distribution measuring device LB-500 manufactured by Horiba.

<Specific resistivity>
When the size of the conductor sheet is sufficient, it is punched into a dumbbell type specified by ISO 527-2-1A, and the dumbbell type test piece is 10 mm wide and 80 mm long as the test piece. Using. When the conductor sheet could be molded, it was heat-compressed into a sheet having a thickness of 200 ± 20 μm, then punched into a dumbbell shape defined by ISO 527-2-1A, and similarly a test piece was obtained. If the size of the conductor sheet is small and the specified dumbbell shape cannot be obtained, cut out a rectangle with a width and length that can be sampled to make a test piece, and use the measured width, thickness, and length. Converted.
Test piece: The resistance value [Ω] of a portion having a width of 10 mm and a length of 80 mm was measured using a milliohm meter manufactured by Agilent Technologies, and the sheet resistance value “Ω” was multiplied by the aspect ratio (1/8) of the test piece. □ ”.
The resistivity [Ω] was multiplied by the cross-sectional area (width 1 [cm] mm × thickness [cm]) and divided by the length (8 cm) to obtain the specific resistance [Ωcm].

<Washing durability>
A 30-cycle washing test was conducted by the 105 method defined in the indication symbols and indication methods for handling JIS L 0217 textiles.
Washing solution: neutral detergent 0.5% solution water flow: weak bath ratio: 1:60
Laundry net available Laundry cycle Washing 30 ° C 5 minutes Rinse 30 ° C 2 minutes 2 times This cycle is 1 cycle, repeated 30 times.
The operation was confirmed again with the sensor after the test.

<Moisture permeability>
The moisture permeability of the dielectric layer was measured based on the method for testing moisture permeability of the JIS Z 0208 moisture-proof packaging material. In addition, about the printed laminated product, only the dielectric layer was separately printed on the release paper, and evaluation was performed by peeling from the release paper after drying and curing.

<Dielectric breakdown voltage>
The dielectric breakdown strength of the dielectric layer was measured with a parallel plate electrode having a diameter of 25 mm by an alternating current test method based on the JIS C 2151: 2006 electrical plastic film test method. In addition, about the printed laminated product, only the dielectric layer was separately printed on the release paper, and evaluation was performed by peeling from the release paper after drying and curing.

<Salt water immersion change rate>
The stretchable capacitor was immersed in physiological saline at 25 ° C. for 1 hour, and the change rate of the capacitance value before and after immersion by the LCR meter was determined by the following formula.
Salt water immersion change rate (%) = 100 × capacitance after immersion / capacitance before immersion

[Example 1]
10 parts by mass of nitrile butadiene rubber having a nitrile amount of 40% by mass and a Mooney viscosity of 46,
2 parts by mass of nitrile butadiene rubber having a nitrile amount of 32% by mass and a Mooney viscosity of 38,
30 parts by mass of isophorone,
58.0 parts by mass of fine flaky silver powder having an average particle size of 6 μm [trade name Ag-XF301, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd.]
Were uniformly mixed and dispersed with a three roll mill to obtain a stretchable conductive layer forming paste.
The obtained paste for forming a stretchable conductive layer was applied and dried into a release PET film using a slit coater to obtain a stretchable conductor sheet having a thickness of 35 μm.

The obtained stretchable conductor sheet was cut into a width of 10 mm and a length of 200 mm, and the specific resistance was determined from the resistance value and thickness in the length direction. As a result, the specific resistance was 1.2 × 10 ⁻⁴ Ωcm.
Next, both ends of the stretchable conductor sheet in the length direction are sandwiched between clips of a tensile tester, and the effective length is 160 mm and pulled to 320 mm. The resistance value between both ends, the width of the narrowest part of the test piece, and the thickness Was used to calculate the specific resistance at 100% elongation. As a result, the specific resistance at 100% elongation was 58 × 10 ⁻⁴ Ωcm.

30 parts by mass of a nitrile butadiene rubber having a nitrile amount of 40% by mass and a Mooney viscosity of 46,
It was dissolved in 40 parts by mass of isophorone to obtain a stretchable dielectric layer forming paste. The obtained stretchable dielectric layer forming paste was applied and dried on the previously obtained stretchable conductor sheet so as to have a dry thickness of 30 μm to obtain a stretchable dielectric / stretchable conductor sheet. . Further, a hot-melt urethane sheet having a thickness of 50 μm was laminated on the stretchable dielectric layer to obtain a three-layer sheet comprising a hot-melt adhesive layer / stretchable dielectric / stretchable conductor.

A paste for forming a stretchable dielectric layer is applied and dried on a release PET film so as to have a thickness of 50 μm, and the resulting dried sheet is cut into a dumbbell shape and used as a test piece in accordance with ISO 527-1: 2012. Then, the Poisson's ratio of the stretchable dielectric was determined. The result Poisson's ratio was 0.47. Similarly, the Poisson's ratio was measured for a hot-melt urethane sheet having a thickness of 50 μm. As a result, the Poisson's ratio was 0.45.

A stretchable urethane sheet, Mobilon [Nisshinbo Co., Ltd.] is used as a base material, and a three-layer sheet slit to a length of 10 mm and a length of 120 mm so that the configuration of FIG. It was placed and heated and pressed to bond them to obtain a stretchable capacitor.
The obtained stretchable capacitor was sandwiched with clips so that a load was applied to the overlapping part of the three-layer sheets, and the stretch recovery rate at 100% stretch of the stretchable capacitor at 25 ° C. was measured. As a result, the extension recovery rate was 100%.
A conductive wire was attached to the electrode portions at both ends of the obtained elastic capacitor, and the relationship between the elongation in the length direction of the elastic capacitor and the capacitance at 1 MHz was measured using an LCR high tester manufactured by Hioki Electric Co., Ltd. . Both results showed good correspondence. The relationship between the degree of extension and the capacitance was measured at a repetition rate of 1 cycle / second between 0% and 50%. As a result, no hysteresis was observed, indicating a good response.

[Example 2]
In Example 1, a stretchable capacitor was constituted only by a stretchable conductor layer and a hot-melt adhesive layer without using a stretchable dielectric layer forming paste. That is, in this example, the hot melt adhesive layer functions as a dielectric layer of the capacitor.
The evaluation was made in the same manner as in Example 1. As a result, the extension recovery rate at 100% extension was 100%, the relationship between the degree of extension and the capacitance showed a good correspondence of 1: 1, and no hysteresis was observed.

[Example 3]
Using the stretchable sportswear fabric as a base material, the stretchable conductor layer forming paste and the stretchable dielectric layer forming paste obtained in Example 1 were formed into the configuration shown in FIG. 5 using a screen printing method. Print drying was repeated and laminated to obtain an elastic capacitor. The stretchable underlayer, dielectric layer, and insulating cover layer were all composed of a stretchable dielectric layer forming paste. The thickness of each layer obtained by cross-sectional observation is as follows.
Elastic substrate about 800μm
Elastic base layer approx. 70μm
First elastic conductor layer 18μm
Stretchable dielectric layer 24μm
Second stretchable conductor layer 16 μm
Elastic insulation cover layer 23μm
The evaluation was made in the same manner as in Example 1. As a result, the extension recovery rate at 100% extension was 100%, the relationship between the degree of extension and the capacitance showed a good correspondence of 1: 1, and no hysteresis was observed.

[Application Example 1]
A stretchable capacitor having a width of 1 cm and an effective length of 5 cm was produced by the method of Example 1 of the present invention, and was sewn to the chest portion of a compression-type sports shirt. Next, a 25-year-old healthy man was allowed to wear a sports shirt with an elastic capacitor, and the relationship between breathing and capacitance change was determined. The results are shown in FIG.
In FIG.
0-30 seconds Normal breathing 30-60 seconds Inhale and stop 60-70 seconds Normal breathing 70-90 seconds Exhale and stop 100-140 seconds Deep breathing. As a result, it was shown that when the stretchable capacitor of the present invention is used as a sensor element for detecting respiration, the respiration state can be monitored well.

[Example 11]
Nitrile amount 40% by weight, Mooney viscosity 46 nitrile butadiene rubber 12 parts by weight,
30 parts by mass of isophorone,
58.0 parts by mass of fine flaky silver powder having an average particle size of 6 μm [trade name Ag-XF301, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd.]
Were uniformly mixed and dispersed with a three roll mill to obtain a stretchable conductive layer forming paste.
The obtained paste for forming a stretchable conductive layer was applied to a release PET film using a screen printing method and dried to obtain a stretchable conductor sheet having a thickness of 22 μm.

The obtained stretchable conductor sheet was cut into a width of 10 mm and a length of 200 mm, and the specific resistance was determined from the resistance value and thickness in the length direction. As a result, the specific resistance was 1.0 × 10 ⁻⁴ Ωcm.
Next, both ends of the stretchable conductor sheet in the length direction are sandwiched between clips of a tensile tester, and the effective length is 160 mm and pulled to 320 mm. The resistance value of both ends and the width and thickness of the narrowest part of the test piece are determined. Using this, the specific resistance at 100% elongation was calculated. As a result, the specific resistance at 100% elongation was 48 × 10 ⁻⁴ Ωcm. Table 1 shows the evaluation results including other characteristics. Shown in

30 parts by mass of NBR (nitrile butadiene rubber) having a nitrile amount of 40% by mass and a Mooney viscosity of 46 was dissolved in 40 parts by mass of isophorone to obtain a stretchable dielectric layer forming paste. The obtained paste for forming a stretchable dielectric layer was applied and dried on a release PET film using a screen printing method to obtain a stretchable conductor sheet having a thickness of 35 μm. Table 1 shows the evaluation results of the obtained stretchable dielectric layer. Shown in

On the release PET film, in the order of the stretchable conductor-forming paste, the stretchable dielectric-forming paste, and the stretchable conductor-forming paste obtained earlier, printing and drying / curing are repeated using the screen printing method, An elastic capacitor having a laminated structure with a width of 10 mm and a length of 700 mm was obtained. The obtained stretchable capacitor was peeled off from the release PET film, and stretch recovery rate and 20% stretch stress were evaluated. The results are shown in Table 1.

The obtained stretchable capacitor was laminated on a color stretch belt with a length of 900 mm, a width of 24 mm, and a thickness of 1.2 mm using a hot melt adhesive, and crafted so that the circumference could be adjusted with a hook-and-loop fastener. A snap hook was attached to the connector as a connector, and the relationship between the elongation in the length direction of the stretchable capacitor and the capacitance at 1 MHz was measured using an LCR high tester manufactured by Hioki Electric Co., Ltd. Both results showed good correspondence. The relationship between the degree of extension and the capacitance was measured at a repetition rate of 1 cycle / second between 0% and 50%. As a result, no hysteresis was observed, indicating a good response.
Next, the obtained displacement sensor was wrapped around the chest of a 25-year-old healthy man in a state of exhaling, and fixed with a hook-and-loop fastener with a tension that did not slip off in a standing position. In this state, the relationship between respiration and capacitance change was determined. The results are shown in FIG.
In FIG.
0-30 seconds Normal breathing 30-60 seconds Inhale and stop 60-70 seconds Normal breathing 70-90 seconds Exhale and stop 100-140 seconds Deep breathing. As a result, it was shown that when the stretchable capacitor of the present invention was used as a sensor element for detecting respiration, the respiration state could be monitored well. In addition, during the measurement, the subject did not particularly feel uncomfortable.

The obtained displacement sensor was placed in a 300 mm × 300 mm washing net, and the possibility of breath sensing was confirmed again after the washing durability test.
The above results are shown in Table 1. Shown in

[Example 12]
A displacement sensor was manufactured in the same manner as in Example 11 except that urethane resin was used as the stretchable dielectric layer. The evaluation results are shown in Table 1.
[Example 13]
A displacement sensor was manufactured in the same manner as in Example 11 except that natural rubber was used as the stretchable dielectric layer. The evaluation results are shown in Table 1.
[Example 14]
A paste for forming a stretchable conductor was obtained in the same manner as in Example 11 using SBR (styrene-butadiene rubber) as the binder resin. Next, the obtained paste was coated on a release PET film and dried and peeled to obtain a stretchable conductive sheet having a thickness of 56 μm.
The same paste for forming a stretchable dielectric layer as in Example 1 was coated on a release PET film and peeled after drying to obtain a stretchable dielectric sheet having a thickness of 78 μm. Table 1 shows the evaluation results of each sheet. Shown in
A stretchable dielectric sheet is layered on the stretchable conductor sheet obtained, and the stretchable conductor sheet is further stacked to form a three-layer structure, sandwiched between release PET films, laminated in three layers with a hot press, Obtained.
The obtained elastic capacitor was laminated using a foamed rubber belt having a thickness of 3 mm as a belt-like base material to obtain a displacement sensor. The obtained sensor was evaluated in the same manner as in the example. The results are shown in Table 1. The test subject complained of tightness when wearing it, but he was accustomed to the test, and did not complain during the test.
[Example 15]
The stretchable capacitor obtained in Example 14 was similarly wound around the chest of a subject wearing an undershirt, and the respiratory state was evaluated. The results are shown in Table 1.
[Comparative Example 1]
The elastic capacitor obtained in Example 14 was laminated on a rubber belt having a thickness of 3 mm to form a displacement sensor. Respiration sensing was attempted with the obtained displacement sensor, but the test was stopped because the subject felt stuffy.

[Application Example 2]
The displacement sensor obtained in Example 11 was worn by 10 subjects, and the respiratory state at bedtime was sensed for 6 hours. All subjects could wear without any discomfort, and the respiratory condition could be monitored without displacement of the displacement sensor from the chest regardless of the sleeping posture.

[Example 21]
Nitrile amount 40% by weight, Mooney viscosity 46 nitrile butadiene rubber 12 parts by weight,
30 parts by mass of isophorone,
58.0 parts by mass of fine flaky silver powder having an average particle size of 6 μm [trade name Ag-XF301, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd.]
Were uniformly mixed and dispersed with a three roll mill to obtain a stretchable conductive layer forming paste. The obtained paste for forming a stretchable conductive layer was applied to a release PET film using a screen printing method and dried to obtain a stretchable conductor sheet having a thickness of 22 μm.

The obtained stretchable conductor sheet was cut into a width of 10 mm and a length of 200 mm, and the specific resistance was determined from the resistance value and thickness in the length direction. As a result, the specific resistance was 1.0 × 10 ⁻⁴ Ωcm.
Next, both ends of the stretchable conductor sheet in the length direction are sandwiched between clips of a tensile tester, and the effective length is 160 mm and pulled to 320 mm. The resistance value of both ends and the width and thickness of the narrowest part of the test piece are determined. Using this, the specific resistance at 100% elongation was calculated. As a result, the specific resistance at 100% elongation was 48 × 10 ⁻⁴ Ωcm. Table 2 shows the evaluation results including other characteristics. Shown in

30 parts by mass of NBR (nitrile butadiene rubber) having a nitrile amount of 40% by mass and a Mooney viscosity of 46 were dissolved in 40 parts by mass of isophorone to obtain a paste CC1 for forming a stretchable dielectric layer. The obtained paste for forming a stretchable dielectric layer was applied and dried on a release PET film using a screen printing method to obtain a stretchable conductor sheet having a thickness of 35 μm. Table 2 shows the evaluation results of the obtained stretchable dielectric layer. Shown in

On the release PET film, in the order of the stretchable conductor-forming paste, the stretchable dielectric-forming paste, and the stretchable conductor-forming paste obtained earlier, printing and drying / curing are repeated using the screen printing method, An elastic capacitor having a laminated structure with a width of 10 mm and a length of 200 mm was obtained. The obtained stretchable capacitor was peeled off from the release PET film, and stretch recovery rate and 20% stretch stress were evaluated. The results are shown in Table 2.
In addition, silver-coated yarn is connected to both electrodes of the elastic capacitor with conductive adhesive, and the wiring is drawn out and connected to an LCR high tester manufactured by Hioki Electric Co., Ltd. The expansion degree of each elastic capacitor and the capacitance at 1 MHz The relationship was measured. Both results showed good correspondence. The relationship between the degree of extension and the capacitance was measured at a repetition rate of 1 cycle / second between 0% and 50%. As a result, no hysteresis was observed, indicating a good response.

The obtained elastic capacitor was affixed to the inner and outer sides of both elbows of a long-sleeved shirt made of a stretch material using a hot melt adhesive sheet. Next, wiring was sewn with silver-coated threads from both poles of the left and right capacitors to the connector attached to the chest of the long sleeve shirt. In this example, a connector and a Hikari Denki LCR high tester were experimentally connected, and the sensing wear was configured so that the change in capacitance at 1 MHz when the elbow was bent could be monitored.
The obtained sensing wear was worn by a 25-year-old healthy man and the correspondence between bending of the arm (elbow) and capacitance change was measured. As a result, the subject exercised without feeling a sense of incongruity, and the capacitance of the elastic capacitor placed on the outside of the elbow and the bending angle of the elbow were free from hysteresis, and data showing a good correlation could be obtained.
In this example, the arrangement of the elastic capacitors was fixed to the outside and the inside of the elbow. However, if the elastic capacitors are arranged so as to surround the elbow by further increasing the number, the largest change among them is shown. If it is programmed to recognize the output of the elastic capacitor as the elbow bending angle, it is considered that the elbow bending angle can be detected properly even when the long-sleeved shirt is worn slightly shifted. Also. It was also suggested that the elastic capacitor has a sufficient length, so that it can sufficiently cover some differences in physique (arm length).
The obtained sensing wear was placed in a 300 mm × 300 mm washing net, and after confirming whether or not breathing sensing was possible again after the washing durability test, it was confirmed that the device operated without problems.

[Example 22]
An elastic capacitor having a width of 10 mm and a length of 600 mm was manufactured in the same manner as in Example 21 except that urethane resin was used as the elastic dielectric layer. The evaluation results are shown in Table 2.
The obtained stretchable capacitor was affixed around the chest and abdomen of a T-shirt using a stretch material with a hot melt adhesive sheet, and wiring was similarly attached to obtain sensing wear.
The obtained sensing wear was worn by a 25-year-old healthy man, and the correspondence between the sleeping state and the change in capacitance was measured. As a result, the subject was able to sleep well without feeling uncomfortable, and was able to monitor the respiratory state during sleep by changing the capacitance. It was suggested that this sensing wear would be useful for detecting sleep apnea syndrome. There was no problem in operation after the washing test.

[Example 23]
A stretchable capacitor was formed on the substrate by a printing method using natural rubber as the stretchable dielectric layer and using a urethane sheet with a hot melt layer instead of a release PET film as the substrate. In this example, the stretchable conductor layer was extended so that it could be used as a wiring. Paste the obtained elastic capacitor with the hot melt adhesive sheet along the instep and heel part of the sock longitudinal direction, attach a metal snap hook to the end of the wiring with the elastic conductive layer to make a connector, Socks-type sensing wear was obtained.
It was possible to monitor the movement of the ankle satisfactorily without hysteresis with the obtained sensing wear. The subject did not complain. There was no problem in operation after the washing test.

[Example 24]
Using SBR (styrene-butadiene rubber) as the binder resin, a paste for forming a stretchable conductor was obtained in the same manner as in the example. Next, the obtained paste was coated on a release PET film and dried and peeled to obtain a stretchable conductive sheet having a thickness of 56 μm.
The same paste for forming a stretchable dielectric layer as in Example 1 was coated on a release PET film and peeled after drying to obtain a stretchable dielectric sheet having a thickness of 78 μm. Table 2 shows the evaluation results of each sheet. Shown in
A stretchable dielectric sheet is layered on the stretchable conductor sheet obtained, and the stretchable conductor sheet is further stacked to form a three-layer structure, sandwiched between release PET films, laminated in three layers with a hot press, Obtained.
The obtained stretchable capacitor is placed on the waist side, buttocks and knees of the tights and attached with a hot-melt adhesive sheet, wired with silver-coated yarn in the same manner as in Example 1, and sensing for checking the operation of the lower body I got wear. Evaluation was performed in the same manner as in Example 1 below. As a result, it was possible to satisfactorily monitor knee bending and stretching with no hysteresis with the obtained sensing wear. The subject did not complain, and there was no problem in operation after the laundry test.
[Comparative Example 2]
A stretchable capacitor was obtained in the same manner as in Example 24 except that a crosslinked natural rubber sheet was used as the stretchable dielectric layer.
Subsequently, the obtained stretchable capacitor was attached to a long-sleeved shirt in the same manner as in Example 21, and an arm motion monitor test was performed. As a result, it was judged that it was difficult to detect natural movement because the subject felt a great sense of incongruity when bending his arm.

[Example 31]
<Resin production example 1>
Synthesis of polyurethane resin composition (A) In a 1 L four-necked flask, 100 parts of ODX-2044 (DIC polyester diol), 30 parts of 1,6-hexanediol (manufactured by Ube Industries) as a chain extender, diethylene glycol monoethyl ether It was put in 98 parts of acetate and set in a mantle heater. A stir bar with a stirring seal, a reflux condenser, a temperature detector, and a ball stopper were set in the flask and dissolved by stirring at 50 ° C. for 30 minutes. 53 parts of T-100 (produced by Tosoh Corporation, isocyanate) and 0.1 part of dibutyltin dilaurate as a catalyst were added. When the temperature rise due to the reaction heat settled, the temperature was raised to 90 ° C. and reacted for 4 hours to obtain a polyurethane resin composition (A). The obtained resin had a reduced viscosity (dl / g) of 0.81, a glass transition temperature of −20 ° C., a urethane group concentration of 3325 meq / kg, an elastic modulus of 70 MPa, and a breaking elongation of 1180%.

<Example of making conductive paste>
First, dissolve the binder resin in half the amount of the solvent specified, add the metal particles, the treating agent and the remaining solvent to the resulting solution, and after premixing, disperse in a three-roll mill. To obtain a stretchable conductive paste. The paste composition is 6.8 parts by mass of binder resin (obtained polyurethane resin) 73.0 parts by mass of metal-based particles Ag01 78.5 parts by mass of barium sulfate 1.3 parts by mass leveling agent 0.4 parts by mass. Here, the metal-based particles Ag01 are SPH02J (conductive particles, silver powder, average particle size: 1 μm) manufactured by Mitsui Mining & Smelting Co., Ltd.
Solvent: ECA is diethylene glycol monoethyl ether acetate.
Additive: Barium sulfate is B-34 (particle size 0.3 μm) manufactured by Sakai Chemical Industry Co., Ltd.
Additive: Leveling agent is MK Conk manufactured by Kyoeisha Chemical Co., Ltd.
Polyurethane film with hot melt layer manufactured by Nisshinbo Co., Ltd .: Mobilon film MF103F3 (thickness 100 μm, having a hot melt layer on one side) is used as a stretchable dielectric layer, and the resulting stretchable conductive paste is 25 μm thick on both sides It was printed and dried and cured to obtain a stretchable capacitor. The obtained elastic capacitor was evaluated in the same manner as in Example 11. The results are shown in Table 3.
[Example 32]
Nisshinbo Co., Ltd. polyurethane film: Mobilon film MOB100S (thickness: 100 μm) is used as a stretchable dielectric layer, and the stretchable conductive paste obtained in Example 31 is printed on both sides to a thickness of 25 μm and dried. Cured to obtain a stretchable capacitor. The obtained elastic capacitor was evaluated in the same manner as in Example 11. The results are shown in Table 3.
[Example 33]
An NS sheet (thickness 40 μm) made by Nikkan Kogyo Co., Ltd. is used as a stretchable dielectric layer, and the stretchable conductive paste obtained in Example 31 is printed on both sides to a thickness of 25 μm, dried and cured, and stretchable. A capacitor was obtained. The obtained elastic capacitor was evaluated in the same manner as in Example 11. The results are shown in Table 3.
[Example 34]
DINGZING polyurethane film: Proveta FS1123 (thickness 50 μm) as a stretchable dielectric layer, and the stretchable conductive paste obtained in Example 31 is printed on both sides to a thickness of 25 μm and dried and cured. An elastic capacitor was obtained. The obtained elastic capacitor was evaluated in the same manner as in Example 11. The results are shown in Table 3.

Industrial application fields

As described above, the elastic capacitor of the present invention is useful as a sensor element for detecting various displacements and deformations because it exhibits a good correspondence between the elongation in the length direction and the electrostatic capacity. The stretchable capacitor of the present invention is useful as a sensor element for detecting various displacements and deformations because the elongation in the length direction and the capacitance show a good correspondence without hysteresis. Furthermore, since the stretchable capacitor of the present invention has a low stress at the time of stretching, it is wrapped in the body as it is or in combination with a belt-like base material having a small stretching stress, and the subject's feeling of strangeness is felt by breathing. It can be measured without giving. Furthermore, the sensing wear using the stretchable capacitor of the present invention has a natural wearing feeling, and can measure the forward and backward movement and state in a non-invasive state. In this embodiment, a desktop type LCR high tester was used as a test, but in practice, remote measurement is possible by combining a small measuring instrument and a communication function. The sensing wear of the present invention can detect not only limb movement, body shape, posture, but also breathing, mastication, swallowing, pulsation, fetal movement, etc. It is possible to monitor the body during driving and various work, and it can also be applied to motion capture. Furthermore, the present invention can be applied not only to the human body but also to animals and mechanical devices.

1. Elastic conductor layer (surface electrode)
2. 2. Stretchable dielectric layer Elastic conductor layer (back electrode)
4). Elastic conductor 5. Stretchable dielectric material6. 6. Hot melt adhesive layer Base material 11. Elastic substrate 12. Elastic base layer 13. First stretchable conductor layer 14. Stretchable dielectric layer 15. Second stretchable conductor layer 16. Elastic insulating cover layer 17. Back electrode 18. Through hole 19. Temporary substrate

Claims

A capacitor having at least a layer structure in which a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer are laminated in this order, wherein the stretchable conductor layer is a composition containing metal particles and is non-stretchable A stretchable capacitor characterized in that the specific resistance at the time is 3 × 10 −3 Ωcm or less and the specific resistance at 100% elongation is within 100 times that at non-extension.
The stretchable dielectric layer contains an inorganic filler having a relative dielectric constant of 2.5 or more at no load and a relative dielectric constant of 5 or more in a proportion of 10% by mass or less. The stretchable capacitor according to claim 1.
The stretchable conductor layer is composed of a stretchable conductor composition containing at least metal particles and a flexible resin having a tensile modulus of elasticity of 1 MPa or more and 1000 MPa or less. The stretchable capacitor according to claim 1 or 2, wherein the content is 7 to 35 mass% with respect to the total.
The stretchable capacitor according to any one of claims 1 to 3, wherein the stretchable dielectric layer has hot-melt adhesiveness.
The stretchable capacitor according to any one of claims 1 to 4, wherein the stretchable dielectric layer has a moisture permeability of 4000 g / m2 · 24 hr or less.
6. The elastic capacitor according to claim 1, wherein the elastic dielectric layer has a dielectric breakdown voltage of 1.0 kV or more.
The stretchable capacitor according to any one of claims 1 to 6, wherein the stretchable dielectric layer has a multilayer structure having a layer having a hot-melt adhesive property on at least one surface.
The stretchable capacitor according to any one of claims 1 to 7, wherein a stretch recovery rate when stretched 100% in a plane direction is 98% or more.
A surface of the stretchable dielectric layer of the stretchable capacitor according to any one of claims 1 to 8 is arranged so as to face a deformation direction of the measurement target, and the stretchable capacitor changes according to the stretch deformation of the measurement target. A deformation sensor that detects deformation of a measurement object by detecting a change in capacitance.
The capacitance change of the stretchable capacitor that changes in accordance with the stretch deformation of the measurement object is mainly caused by the stretch in the thickness direction of the stretchable dielectric layer accompanying the stretch in the surface direction of the stretchable dielectric layer. The deformation sensor according to claim 9, wherein the deformation sensor is a change in electric capacity.
A displacement sensor characterized by comprising at least a belt-like base material made of a stretchable material and a stretchable capacitor that can be deformed according to the expansion and contraction of the belt-like base material.
12. The displacement sensor according to claim 11, wherein the deformation of the elastic capacitor is a deformation in a surface direction of the dielectric layer of the capacitor.
The stretchable capacitor is a capacitor having a layer structure in which a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer are laminated in this order, and the specific resistance of the stretchable conductor layer is 1 × 10 −3. The displacement sensor according to claim 11 or 12, wherein the stretchable dielectric layer is made of a stretchable insulating polymer having a tensile yield elongation of 70% or more.
The displacement sensor according to any one of claims 11 to 13, wherein a stress at the time of 20% elongation in the belt length direction of the displacement sensor is 20 N or less.
The displacement sensor according to any one of claims 11 to 14, wherein a portion including the elastic capacitor is 10% or more and 100% or less with respect to the entire length of the belt-like object.
A respiratory state sensing method, wherein the displacement sensor according to any one of claims 11 to 15 is arranged around a human torso and a respiratory state is detected by measuring a change in circumference of the torso.
Sensing ware characterized by the provision of electrical wiring for connecting stretchable capacitors, stretchable capacitors, and devices that detect the capacitance of stretchable capacitors.
The stretchable capacitor is a capacitor having a layer structure in which a stretchable conductor layer, a stretchable dielectric layer, and a stretchable conductor layer are laminated in this order, and the specific resistance of the stretchable conductor layer is 1 × 10 −3. 18. The sensing wear according to claim 17, wherein the stretchable dielectric layer is made of a stretchable insulating polymer having a tensile yield elongation of 70% or more.
The sensing ware according to claim 17 or 18, wherein the elastic capacitor is arranged so that the deformation of the elastic capacitor is in the direction of the wear.
The sensing wear according to any one of claims 17 to 19, wherein a stress at the time of 20% elongation in the surface direction of the elastic capacitor is 15 N / cm or less.
It is a clothing for the upper body of the human body, characterized in that the elastic capacitor is disposed at least at any of the elbow, upper arm, lower arm, shoulder, back, chest, abdomen, and flank. The sensing wear according to any one of claims 17 to 20.
18. The garment for the lower body of the human body, wherein the stretchable capacitor is disposed at least at any one of a knee part, an ankle part, a thigh circumference, a shin circumference, a hip joint part, and a waist part. To Sensingware according to any one of 20.
The sensing wear according to any one of claims 17 to 20, wherein the sensing wear is a glove shape, and the stretchable capacitor is disposed at least in one portion of each joint of the wrist and fingers.
The sensing ware according to any one of claims 17 to 20, wherein the sensing ware has a sock shape, and the stretchable capacitor is disposed at least in one portion of each joint of the ankle and toe.