JP2020198396A - Battery-less electronic device and transmission system - Google Patents

Abstract

To provide a battery-less electronic device capable of operating an electronic element stably, while improving mountability more than before, and capable of compaction, and to provide a transmission system using the same.SOLUTION: In a battery-less electronic device 3, electrodes 6, 7 are attached to human body 100 by a thin polymer nanosheet 10, and thereby mountability can be improved. Furthermore, since a thin polymer nanosheet 10 is used, the battery-less electronic device 3 adheres easily to the human body 100 by intermolecular force, and thereby formation of air layer between the electrodes 6, 7 and the human body 100 is prevented, and decrease of capacity C can be suppressed. Consequently, in the battery-less electronic device 3, the capacity C can be increased without designing the inductance in impedance matching, and an electronic element 8 can be operated stably. The electronic element 8 can be operated even in a state where the surface area S of the electrodes 6, 7 or the anode-cathode distance L is decreased.SELECTED DRAWING: Figure 2

Description

The present invention relates to batteryless electronic devices and transmission systems.

In recent years, the development of wearable electronics for the purpose of continuous measurement of biological information and personal authentication has been progressing. As a method of directly fixing an electronic device to an arm or leg, a technique using a flexible substrate is being developed, and research is being conducted on a device that can be attached to a highly elastic biological tissue such as skin. It has been. Among them, electronic devices using polymer nanosheets with a thin film thickness can manufacture electronic devices whose constituent elements are electronic elements by a simple process, and can be attached without an adhesive following an object to be attached such as skin. It can be attached (see Patent Document 1).

Regarding the above-mentioned wearable electronics in recent years, various methods have been considered as a method of supplying electric power and transmitting a signal to an electronic device without connecting a battery or the like. For example, NFC (Near Field Communication) using an antenna coil is known as one of the wireless power transmission systems. In addition, as another wireless power transmission system, a high-frequency signal is converted from a magnetic field into an electric field to transmit the electric field to the human body, and based on the electric field, the coupling electrode of the transmission / reception unit attached to the human body and the human body are electrostatically coupled. An electric field type NFC that is electrically connected and transmits a high frequency signal and power to a transmission / reception unit through a human body has been considered (see, for example, Non-Patent Document 1).

International Publication No. 2016/181958

Takanori Washiro, "HF RFID Transponder with Capacitive Coupling" 2017 IEEE International Conference on RFID Technology & Application (RFID-TA)

The present inventors have attempted wireless power transmission using NFC technology having an antenna coil in order to supply power to an electronic device using a polymer nanosheet without a battery. However, it has been discovered that when an electronic device using a polymer nanosheet is attached to the skin, the desired power is not supplied and the operability is reduced. It is considered that this is because the thickness of the nanosheet is thin, and when it is attached to the skin, the capacitance increases and the electromotive force decreases. Therefore, in order to wirelessly supply electric power to the electronic element and operate it stably, the film thickness of the substrate must be increased, and there is a problem that the wearability to the human body or the like cannot be improved.

On the other hand, in the conventional electric field type NFC wireless power transmission system, a transmitter / receiver in which electrodes made of a hard metal plate or the like are provided in a housing made of a hard resin material is simply attached to the human body using a band or the like. Therefore, it is difficult for the transmitting / receiving portion to follow the curved surface of the arm or the unevenness of the skin, and a gap may be formed between the electrode and the skin to form an air layer, and the electrostatic coupling becomes small.

Therefore, as a means of eliminating the decrease in capacitance between the electrode and the skin, it is necessary to perform impedance matching using an inductor (coil) having an inductance that satisfies the resonance frequency, but the capacitance is actually increased. Since measurement is difficult, it is also difficult to set an appropriate inductance, and it is difficult to design impedance matching. Further, since the capacitance varies greatly among individuals, it is difficult to adjust the inductance for each individual, and there is a problem that it is actually difficult to operate the RFID tag stably.

Therefore, the present invention has been made in consideration of the above points, and is a batteryless electronic device capable of stably operating an electronic element and being miniaturized while improving wearability as compared with the conventional case. , The purpose is to propose a transmission system using it.

In the batteryless electronic device of the present invention, an electronic element, at least two or more electrodes electrically connected to the electronic element, and a polymer nanosheet which is in close contact with a transmission medium and the electrodes are attached to the transmission medium. And, based on the electric field induced in the transmission medium from the outside, power is supplied to the electronic element by electrostatic coupling between the transmission medium and the electrode.

Further, the transmission system of the present invention is a transmission system including a transmission device installed at a predetermined position to generate an electric field and a batteryless electronic device provided in a transmission medium, and the batteryless electronic device is an electronic element. The transmission medium comprises at least two or more electrodes electrically connected to the electronic element, and a polymer nanosheet which is in close contact with the transmission medium and adheres the electrodes to the transmission medium. Electricity is supplied to the electronic element by electrostatic coupling between the transmission medium and the electrodes based on the electric field induced in the transmission medium by contacting the transmission device.

According to the present invention, since the electrode is attached to the transmission medium by using a polymer nanosheet having a thin film thickness, the mountability to the transmission medium can be improved accordingly. Further, by using a polymer nanosheet having a thin film thickness, it becomes easy to adhere to the transmission medium due to the intermolecular force, the formation of an air layer between the electrode and the transmission medium can be prevented, and the decrease in capacitance can be suppressed. .. Therefore, the capacitance can be increased without particularly designing the inductor in impedance matching, and the electronic element can be operated stably. Further, since the electronic element can be operated even when the surface area of the electrodes and the distance between the electrodes for supplying electric power to the electronic element are reduced, the batteryless electronic device can be miniaturized.

It is the schematic which showed the whole structure of the transmission system by this invention. It is an exploded perspective view which showed the structure of the batteryless electronic device of this invention. It is sectional drawing which showed the sectional structure of the batteryless electronic device. FIG. 4A is a schematic view showing a manufacturing process (1) of a batteryless electronic device, FIG. 4B is a schematic view showing a manufacturing process (2) of a batteryless electronic device, and FIG. 4C is a batteryless diagram. It is the schematic which showed the manufacturing process (3) of an electronic device, and FIG. 4D is a schematic diagram which showed the manufacturing process (4) of a batteryless electronic device. FIG. 5A is a schematic view showing a configuration in which the batteryless electronic device used in the verification test is arranged on the flat plate material of the skin model, and FIG. 5B is an electric field of the batteryless electronic device arranged on the flat plate material of the skin model. It is sectional drawing which showed the cross-sectional structure when it was placed on an antenna. It is a graph which showed the operation rate of the IC tag when the surface area of an electrode and the distance between electrodes are changed. It is a graph which showed the operation rate of the IC tag when the film thickness of the sticking sheet was changed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(1) Outline of the Transmission System of the Present Invention FIG. 1 is a schematic view showing the overall configuration of the transmission system 1 of the present invention, and the transmission system 1 includes a transmission device 2 and a batteryless electronic device 3. In this transmission system 1, when the user touches the transmission device 2, the electric field generated by the transmission device 2 is transmitted to the user's human body 100, and the electric power is transmitted to the batteryless electronic device 3 by electrostatic coupling with the human body 100. Supply can be made.

On the other hand, when the user is not touching the transmission device 2, the electric field generated by the transmission device 2 is not transmitted to the human body 100, so that the supply of electric power to the batteryless electronic device 3 can be stopped. In this way, in the transmission system 1, the batteryless electronic device 3 can be operated only while the user is touching the transmission device 2.

In this case, the transmission device 2 is, for example, a reader / writer, which is installed in advance at a predetermined location such as a desk or a housing, and is virtually short-circuited to the ground VG1 at the installation location. The transmission device 2 passively converts a predetermined high-frequency signal from a magnetic field into an electric field, and transmits the electric field to the user's human body 100 by, for example, touching the electric field antenna 4 of the transmission device 2 with a fingertip.

The batteryless electronic device 3 is attached directly to the skin such as an arm and attached to the human body 100, for example. In the case of this embodiment, the batteryless electronic device 3 has two electrodes 6 and 7, and the electronic element 8 is electrically connected to these electrodes 6 and 7.

FIG. 1 shows an example in which an arm is selected as a position where the batteryless electronic device 3 is attached to the human body 100. For example, in the arm, two electrodes 6 and 2 along the hand side to the shoulder side of the human body 100. 7s are installed so as to line up in a row. In this embodiment, the two electrodes 6 and 7 of the batteryless electronic device 3 are attached to the arm, but the present invention is not limited to this, and for example, the back of the hand, the palm, the wrist, the shoulder, the body, etc. It may be attached to various parts of the human body 100. Further, the two electrodes 6 and 7 may be attached side by side in a row in various directions such as the circumferential direction of the arm.

Here, in the transmission system 1, when the user in contact with the ground touches the transmission device 2 by hand, the human body region ER2 on the electrode 7 side on the shoulder side (position away from the transmission device 2) of the batteryless electronic device 3 Virtually short-circuits to the ground VG2, while the human body region ER1 on the electrode 6 side on the hand side (position close to the transmission device 2) of the batteryless electronic device 3 functions as a transmission medium. As a result, in the transmission system 1, the electric field antenna 4 of the transmission device 2 and the electrode 6 on the hand side (transmission device 2 side) of the batteryless electronic device 3 are connected via the human body 100.

In this way, the transmission system 1 operates as if it were a closed circuit via the virtual ground VG1 and VG2 as a whole, thereby stably supplying electric power from the transmission device 2 to the batteryless electronic device 3. Can be supplied.

Here, as described above, when the human body 100 is used as the transmission medium which is a dielectric, it is desirable that the frequency of the high frequency signal generated by the transmission device 2 is a frequency having high transmission efficiency in the human body 100. For example, it is preferably 7 to 21 MHz, 33 to 45 MHz, and more preferably 13.56 MHz.

(2) Detailed Configuration of Batteryless Electronic Device Next, the batteryless electronic device 3 described above will be described in detail. FIG. 2 is an exploded perspective view of the batteryless electronic device 3 of the present invention attached to the skin 100a. The batteryless electronic device 3 electrically attaches the polymer nanosheet 10, the pair of electrodes 6 and 7, the electronic element 8, and these electrodes 6 and 7 and the electronic element 8 to be attached so as to be in close contact with the skin 100a. It is composed of a wiring 9 connected to the polymer nanosheet 10 and a second polymer nanosheet 11 attached on the polymer nanosheet 10.

The polymer nanosheet 10 is provided with a pair of electrodes 6 and 7, an electronic element 8 and a wiring 9 on the surface thereof, and a second electrode 6, 7 and the electronic element 8 and the wiring 9 are covered as a whole. The polymer nanosheet 11 of the above is attached to the surface. As a result, the electrodes 6 and 7, the electronic element 8 and the wiring 9 are sandwiched between the polymer nanosheet 10 and the second polymer nanosheet 11.

The polymer nanosheet 10 is formed to have a thin film thickness, and can be adhered to the skin 100a by an intermolecular force without using glue or the like. Further, since the polymer nanosheet 10 is adhered to the skin 100a due to the intermolecular force generated by reducing the film thickness, the skin follows the curved surface of the skin 100a and the uneven surface shape of the skin 100a. It can be adhered along 100a.

As shown in FIG. 3 showing the cross-sectional structure of the AA' portion of FIG. 2, the second polymer nanosheet 11 follows the uneven shape of the electrodes 6 and 7, the electronic element 8 and the wiring 9 by the intermolecular force. The electrodes 6 and 7, the electronic element 8, the wiring 9, and the polymer nanosheet 10 are in close contact with each other. The second polymer nanosheet 11 is attached to the polymer nanosheet 10 in a state of being in close contact with the electrodes 6 and 7, the electronic element 8 and the wiring 9 by intermolecular force without chemical bonding such as soldering. can do.

In this case, in the batteryless electronic device 3, the electrodes 6 and 7, the electronic element 8 and the wiring 9 are connected to the polymer nanosheet 10 and the second polymer in a state where the electronic element 8 and the wiring 9 are electrically connected. It is sandwiched between nanosheets 11 and is in close contact with each other due to the intermolecular force of the polymer nanosheet 10 and the second polymer nanosheet 11. As a result, the electronic element 8 is crimped to the wiring 9 by the intermolecular force, and the wiring 9 can be connected to the electronic element 8 with a strong adhesive force. Therefore, the wiring 9 can be electronically connected without any soldering or the like. It can be electrically connected to the element 8.

Examples of the electronic element 8 include a light emitting element such as a light emitting diode (LED), an active component such as a transistor, a diode, and an IC, and a passive component such as a resistor, an inductor, and a capacitor. Further, as the electronic element 8, various sensors such as a strain sensor and an RFID tag can be provided. Further, in the batteryless electronic device 3 of the present invention, for example, two or more electronic elements having different functions and uses may be integrally or separately provided as one electronic element 8.

The electrodes 6 and 7 and the wiring 9 can be formed of, for example, a conductive ink containing at least one of metal nanoparticles, semiconductor nanoparticles, a conductive polymer, and a nanocarbon material. In particular, metal nanoparticles such as silver, gold, copper and nickel are relatively easily available and have a low resistivity, and are therefore preferable as materials for forming the electrodes 6 and 7 and the wiring 9. Further, as a method for forming the patterns of the electrodes 6 and 7 and the wiring 9, the electrodes 6 and 7 and the wiring 9 are formed on the polymer nanosheet 10 by using a simple method such as offset printing or screen printing in addition to inkjet printing. It can be printed and formed.

By forming the electrodes 6 and 7 and the wiring 9 on the polymer nanosheet 10 with such conductive ink, the flexibility is higher than that of a hard material such as a metal plate, and the deformation of the polymer nanosheet 10 is followed. Can be transformed. Therefore, in the batteryless electronic device 3 of the present invention, the polymer nanosheet 10, the electrodes 6, 7 and the wiring 9 all follow the curved surface of the skin 100a and the uneven surface shape of the skin 100a, and the whole follows the skin 100a. Can be brought into close contact. As a result, in the batteryless electronic device 3, it is difficult for a gap to be formed between the skin 100a and the skin 100a, and it is possible to prevent an air layer from being formed between the skin 100a and the electrodes 6 and 7.

In the case of this embodiment, as shown in FIG. 2, the electrodes 6 and 7 have the same shape and are formed in a four-sided shape, but the present invention is not limited to this, and the electrodes 6 and 7 are different. The shape may be used, and electrodes formed in a polygonal shape such as a pentagonal shape or a circular shape may be applied.

The larger the surface area S of the electrodes 6 and 7 attached to the skin 100a by the polymer nanosheet 10, the stronger the bond with the skin 100a, the more stable the power supply from the human body 100 to the electronic element 8, and the more stable the electronic element. It has been confirmed by the verification tests of the present inventors that the operating rate of 8 is improved, but the surface area S of the electrodes 6 and 7 capable of supplying electric power to the electronic element 8 is, for example, 400 mm ² or less. Is preferable. In the present embodiment, since the polymer nanosheet 10 having a thin film thickness d and being able to adhere along the human body 100 is used, the surface area S of the electrode for supplying electric power to the electronic element 8 is reduced. However, the electronic element 8 can be operated, and the batteryless electronic device 3 can be miniaturized accordingly. According to the verification test described later, if the surface area S of the electrodes 6 and 7 is more than 100 mm ² , electric power can be supplied to the electronic element 8.

Further, as shown in FIG. 3, the distance L from the end of the first electrode 6 to the end of the second electrode 7 paired with the first electrode 6 (hereinafter, also simply referred to as the distance between the electrodes). It has been confirmed by the verification tests of the present inventors that the larger the value, the more stable the power supply from the human body 100 to the electronic element 8 and the higher the operating rate of the electronic element 8, but the electric power to the electronic element 8 The distance L between the electrodes to which the above can be supplied is preferably, for example, 30 mm or less. In the present embodiment, since the polymer nanosheet 10 having a thin film thickness d and being able to adhere along the human body 100 is used, the distance L between the electrodes for supplying electric power to the electronic element 8 is reduced. However, the electronic element 8 can be operated, and the batteryless electronic device 3 can be miniaturized accordingly. According to a verification test described later, electric power can be supplied to the electronic element 8 even if the distance L between the electrodes is 10 mm or more.

In the case of this embodiment, the polymer nanosheet 10 to which the electrodes 6 and 7 are attached to the skin 100a and the second polymer nanosheet 11 to be attached to the polymer nanosheet 10 are made of the same material. It has the same configuration.

As the polymer nanosheet 10 and the second polymer nanosheet 11, for example, a polymer such as a synthetic polymer, a natural polymer, rubber, or an elastomer can be used as a material. More specifically, the polymer nanosheet 10 and the second polymer nanosheet 11 are polystyrene isoprene styrene, polydimethylsiloxane, silicone, polystyrene, polymethacrylic acid, polylactic acid, polylactic acid glycolic acid copolymer, polyvinyl acetate. , Chitosan, alginic acid, cellulose acetate, hyaluronic acid, gelatin, and collagen, preferably one of them.

By producing the polymer nanosheet 10 and the second polymer nanosheet 11 from such a material, the polymer nanosheet 10 and the second polymer have high adhesion and elasticity to an object to be attached such as skin 100a. Nanosheets 11 can be provided. As an example of the polymer nanosheet, the following documents can be referred to. T. Fujie and S. Takeoka, in Nanobiotechnology, eds. D. A. Phoenix and A. Waqar, One Central Press, United Kingdom, 2014, pp. 68-94.

The polymer nanosheet 10 and the second polymer nanosheet 11 may be formed to have a thin film thickness d from the viewpoint of followability to the object to be attached. In particular, when the thickness d of the polymer nanosheet 10 and the second polymer nanosheet 11 is 2 μm or more, the followability to the object to be attached such as the electronic element 8 and the skin 100a is inferior, while it is less than 2 μm. The thickness is preferably less than 2 μm because the followability to the object to be attached such as the electronic element 8 and the skin 100a is improved and the adhesion can be improved. Further, when the thickness d of the polymer nanosheet 10 and the second polymer nanosheet 11 is less than 1 μm, the followability to the object to be attached such as the electronic element 8 and the skin 100a becomes higher, and the intermolecular force is also large. It is more preferable that the thickness is less than 1 μm because the adhesion is further enhanced. Further, when the film thickness of the polymer nanosheet 10 and the second polymer nanosheet 11 is 250 nm or less, the followability is further enhanced and the adhesion is further enhanced, so that it is more preferably 250 nm or less.

As described above, the polymer nanosheet 10 can be formed to have an extremely thin film thickness d, and further, it can be brought into close contact with the skin 100a by an intermolecular force to suppress the formation of an air layer and increase the dielectric constant. Minutes, Capacitance C between electrodes 6 and 7 and human body 100 (C = εo ・ ε ・ S / d, εo: vacuum permittivity, ε: relative permittivity, S: electrode surface area, d: high The thickness of the molecular nanosheet) can be made sufficiently high.

(3) Manufacturing Method of Batteryless Electronic Device Next, a manufacturing method of the batteryless electronic device 3 will be described. As shown in FIG. 4A, first, a substrate 16 for producing a polymer nanosheet 10 is prepared, and a sacrificial layer 15 and a polymer nanosheet 10 are sequentially formed on the surface of the substrate 16. Here, the substrate 16 includes PET (polyethylene terephthalate), PP (polypropylene), PPE (polyphenylene ether), COP (cycloolefin), PI (polyimide), aluminum foil, conductive polymer film, paper, and polysaccharide film. , Silicone resin, oblate (polypropylene), silicon wafer, glass and the like can be used.

The sacrificial layer 15 is used to separate the polymeric nanosheet 10 from the substrate 16. In this case, as the material of the sacrificial layer 15, for example, PVA (polyvinyl alcohol), PNIPAM (polynypam), sodium alginate and the like can be used, but in addition, it has a property of being soluble in liquid (water-soluble, oil-soluble, etc.). However, various materials can be used as long as they are highly biocompatible (not harmful to the human body). The sacrificial layer 15 may be formed by a roll-to-roll technique using a gravure coater (not shown), or may be formed by using a spin coater (not shown). In the roll-to-roll technique, a film can be formed in a larger area than when a spin coater is used.

Similar to the sacrificial layer 15 described above, the polymer nanosheet 10 is formed on the sacrificial layer 15 by using a roll-to-roll technique using a gravure coater (not shown) or a film forming method such as a spin coater.

Next, the conductive material is ejected onto the polymer nanosheet 10 by inkjet, and the electrodes 6 and 7 and the wiring 9 are drawn on the surface of the polymer nanosheet 10 to draw the electrodes 6 and 7 and the wiring 9 on the polymer nanosheet 10 as shown in FIG. 4B. The electrodes 6 and 7 and the wiring 9 having a predetermined shape are formed.

Next, as shown in FIG. 4C, the electronic element 8 is arranged on the polymer nanosheet 10 so as to be electrically connected to the wiring 9, and the electronic element 8 is brought into close contact with the polymer nanosheet 10. Next, a second polymer nanosheet 11 to be bonded to the polymer nanosheet 10 is prepared. At this time, the second polymer nanosheet 11 is provided with, for example, a frame 17 made of paper tape along the peripheral edge. Next, the second polymer nanosheet 11 is bonded to the polymer nanosheet 10 by holding the frame 17, and a polymer nanosheet bonded body (not shown) is produced.

Next, the polymer nanosheet bonded body is immersed in a stripping solution such as water to dissolve the sacrificial layer 15 and separate the substrate 16 from the polymer nanosheet 10. As a result, as shown in FIG. 4D, the batteryless electronic device 3 having the frame 17 along the peripheral edge of the second polymer nanosheet 11 can be manufactured. The frame 17 may be removed from the second polymer nanosheet 11 as needed when the batteryless electronic device 3 is attached to the human body 100 or the like.

In the above-described embodiment, the step of forming the sacrificial layer 15 is included, but the present invention is not limited to this, and the step of forming the sacrificial layer 15 is omitted, and the polymer nanosheet 10 is directly on the substrate 16. May be formed. In this case, the substrate 16 is formed of a material having low adhesion to the polymer nanosheet 10, and the frame 17 of the second polymer nanosheet 11 provided in a later step is used to finally obtain the polymer nanosheet. The substrate 16 can be separated from the 10.

Further, a step of forming an ink receiving layer (not shown) may be provided on the polymer nanosheet 10 before the step of forming the electrodes 6 and 7 and the wiring 9. By printing the electrodes 6 and 7 and the wiring 9 on the ink receiving layer with the conductive ink, the fine electrodes 6 and 7 and the wiring 9 can be formed more accurately without the conductive ink being repelled.

In this case, chitosan, polyvinyl acetate, cellulose acetate, gelatin, silica, and a cationic acrylic copolymer are desirable for the ink receiving layer. The ink receiving layer can be formed on the polymer nanosheet 10 by using a roll-to-roll technique using a gravure coater or the like, similarly to the sacrificial layer 15 and the polymer nanosheet 10 described above.

(4) Actions and effects In the above configuration, in the batteryless electronic device 3, the electronic element 8 and the two electrodes 6 and 7 are electrically connected, and the polymer nanosheet 10 is brought into close contact with the human body 100 which is a transmission medium. Then, the electrodes 6 and 7 are attached to the human body 100. Further, in the batteryless electronic device 3, electric power is supplied to the electronic element 8 by electrostatic coupling between the human body 100 and the electrodes 6 and 7 based on an electric field induced in the human body 100 from the outside.

In the batteryless electronic device 3, the electrodes 6 and 7 can be attached to the human body 100 by the polymer nanosheet 10 having a thin film thickness, so that the wearability to the human body 100 can be improved. Further, by using the polymer nanosheet 10 having a thin film thickness, the batteryless electronic device 3 easily adheres to the human body 100 due to the intermolecular force, and prevents the formation of an air layer between the electrodes 6 and 7 and the human body 100. However, the decrease in capacitance C can be suppressed. Therefore, in the batteryless electronic device 3, the capacitance C can be increased without particularly designing the inductor in impedance matching, and the electronic element 8 can be operated stably. Further, since the electronic element 8 can be operated even when the surface area S of the electrodes 6 and 7 and the distance L between the electrodes for supplying electric power to the electronic element 8 are reduced, the batteryless electronic device 3 can be used. It can be miniaturized.

Further, in the batteryless electronic device 3, the electronic element 8 is crimped to the wiring 9 by the intermolecular force of the polymer nanosheet 10 and the second polymer nanosheet 11 without any soldering or the like, and the wiring 9 is connected. It can be connected to the electronic element 8 with a strong adhesive force. As a result, the batteryless electronic device 3 is flexible because it does not use a hard adhesive such as solder, and follows the curved surface of the skin 100a and the surface shape of the uneven skin 100a. Therefore, it is possible to prevent the formation of an air layer between the electrodes 6 and 7 and the human body 100, and to suppress a decrease in the capacitance C between the human body 100 and the electrodes 6 and 7.

(5) Verification test (5-1) Operation confirmation test of batteryless electronic device using polymer nanosheets Here, the batteryless electronic device 3 shown in FIG. 2 was actually manufactured, and a commercially available reader / writer and electric field antenna were manufactured. (Product name eNFC starter kit manufactured by eNFC Co., Ltd.) was used to confirm the operation of the batteryless electronic device 3 of the present invention.

Here, in the batteryless electronic device 3 used in the verification test, a PET film (Lumirror25T60, manufactured by Panac) was used as the substrate 16 used when forming the polymer nanosheet 10. The sacrificial layer 15 was formed on the substrate 16 using a water-soluble polyvinyl alcohol (PVA, manufactured by Kanto Chemical Co., Inc., 10 wt% in water) and a gravure coater (ML-120, manufactured by Yasui Seiki Co., Ltd.).

The polymer nanosheet 10 was formed on the sacrificial layer 15 using styrene-butadiene styrene (SBS, manufactured by Sigma Aldrich Japan, 3 wt% intetrahydrofuran) using a roll-to-roll technique using a gravure coater.

Then, when the film thickness of the polymer nanosheet 10 on the substrate 16 was measured using an atomic force microscope (AFM), the film thickness was 800 nm.

Then, using a screen mask on which electrodes 6 and 7 and wiring 9 having a desired shape and size are formed, electrodes 6 and 7 and wiring 9 are formed with conductive silver ink (TB3303G (NEO), manufactured by Threebond) by screen printing. Electrodes 6 and 7 and wiring 9 were formed by drawing on the surface of the polymer nanosheet 10. The electrodes 6 and 7 were formed in a square shape of 20 mm × 20 mm to have a surface area of 400 mm ^2, and the distance L between the electrodes 6 and 7 was 30 mm.

An IC tag (manufactured by NXP Semiconductors, operating voltage 1.5 V, power consumption 40 μW) is prepared as the electronic element 8, and the wiring 9 extending from the first electrode 6 and the wiring 9 extending from the second electrode 7 are used. The IC tags were installed so as to be electrically connected to each other. Then, a second polymer nanosheet 11 made of the same SBS as the polymer nanosheet 10 is prepared, and the second polymer nanosheet 11 is provided on the polymer nanosheet 10 provided with the electrodes 6, 7, the wiring 9, and the electronic element 8. After sticking, it was immersed in water which is a release liquid.

As a result, the sacrificial layer 15 was dissolved with water, and the substrate 16 was separated from the polymer nanosheet 10 to prepare a batteryless electronic device 3.

Next, in order to reproduce the state in which the batteryless electronic device 3 is attached to the human body 100, the same electrical characteristics as the skin 100a (relative permittivity: 150, conductivity: 0.6 S / m (reference: https: https: //www.asahi-rubber.co.jp/products/denjiha/01.html "Rubber phantom for human body communication / permittivity, conductivity frequency characteristics"))) (made by Asahi Rubber Co., Ltd.) A plate-shaped phantom (hereinafter, also referred to as a skin model) was prepared, and the polymer nanosheet 10 of the batteryless electronic device 3 was attached to the surface of the flat plate material.

As the transmission device 2, a commercially available eNFC starter kit (manufactured by eNFC Co., Ltd.) was used. The reader / writer of the eNFC starter kit is a product name TR3X-MU01 manufactured by Takaya Co., Ltd., and has a frequency of 13.56 MHz and a transmission output of 300 mW ± 20%.

Then, the reader / writer was operated, and the back surface of the flat plate material held by hand was simply brought into contact with the electric field antenna connected to the reader / writer. At this time, it was confirmed whether or not the IC tag of the batteryless electronic device 3 attached to the surface of the flat plate material operates by the electric field generated by the electric field antenna. Whether or not the IC tag is operating was confirmed by checking whether or not the UID (Unique ID unique ID number) of the IC tag read by the reader / writer is displayed on the screen of the personal computer. As a result, it was confirmed that the IC tag of the batteryless electronic device 3 operates by bringing the back surface of the flat plate material into contact with the electric field antenna.

(5-2) Operating rate of the batteryless electronic device when the surface area of the electrodes and the distance between the electrodes are changed Next, the surface area S of the electrodes of the batteryless electronic device and the distance L between the electrodes are changed to change the batteryless electronic device. A verification test was conducted to confirm how the operating rate changes.

In this verification test, a batteryless electronic device 20 as shown in FIGS. 5A and 5B was manufactured. Here, the film thickness of the polymer nanosheet 10 alone is too thin, and it is difficult to reproduce accurate dimensions for the electrodes 6 and 7 having the same size and shape and the distance L between the electrodes. Therefore, in this verification test, the electrodes 6 and 7 having a predetermined size and shape and the distance L between the electrodes having a predetermined length are accurately reproduced on the surface of the polymer nanosheet 10 on the support substrate 23 whose hardness is adjusted. The support substrate 23 was used as it was without being separated from the polymer nanosheet 10.

As for the support substrate 23, the substrate 16 and the sacrificial layer 15 used for forming the polymer nanosheet 10 were used as they were, and these substrates 16 and the sacrificial layer 15 were used as the support substrate 23. In this case, a substrate 16 formed of PET (polyethylene terephthalate) was used, and the sacrificial layer 15 was formed on the substrate 16 with PVA (polyvinyl alcohol).

Then, in the same manner as in the verification test described above, the polymer nanosheet 10 was formed on the support substrate 23, and a plurality of adhesive sheets 24 on which the polymer nanosheet 10 was formed on the surface of the support substrate 23 were produced. In this verification test, the film thickness d1 of the adhesive sheet 24, which is the combination of the support substrate 23 and the polymer nanosheet 10, was set to 30 μm.

Next, using a screen mask on which electrodes 6 and 7 and wiring 9 of a desired size are formed, the square electrodes 6 and 7 are formed by screen printing with conductive silver ink (TB3303G (NEO), manufactured by Threebond). , The strip-shaped wiring 9 was formed on the polymer nanosheet 10, and at this time, by changing the screen mask, the surface surfaces S of the electrodes 6 and 7 on the polymer nanosheet 10 and the distance L between the electrodes were attached. It was changed for each sheet 24.

An IC tag (manufactured by NXP Semiconductors, operating voltage 1.5 V, power consumption 40 μW) was used as the electronic element 8. Then, the IC tag was installed on the polymer nanosheet 10 so that the IC tag was electrically connected to the wiring 9 connected to the first electrode 6 and the wiring 9 connected to the second electrode 7.

In this verification test, the surface areas S of the square electrodes 6 and 7 were changed to 10 mm × 10 mm, 20 mm × 20 mm, and 30 mm × 30 mm, respectively, and the distances L between the electrodes were changed to 10 mm, 20 mm, and 30 mm for each of these surface areas S, respectively. Nine types of batteryless electronic devices 20 were produced, five each.

Next, in order to reproduce the state in which the batteryless electronic device 20 is attached to the human body 100, a rubber flat plate material 101 (plate-shaped phantom manufactured by Asahi Rubber Inc.) is used as a skin model in the same manner as in the above-mentioned verification test. A plurality of sheets were prepared, and each batteryless electronic device 20 was attached to the surface of the flat plate material 101 for each flat plate material (skin model) 101.

Then, as in the above-mentioned verification test, a commercially available eNFC starter kit (manufactured by eNFC Co., Ltd.) is used to operate the reader / writer of the eNFC starter kit, and each flat plate material is attached to the electric field antenna 102 connected to the reader / writer. The back surface of 101 was simply brought into contact.

At this time, it was confirmed whether or not the IC tag of the batteryless electronic device 20 attached to the surface of each flat plate member 101 operates by the electric field generated by the electric field antenna 102. As a result, the result shown in FIG. 6 was obtained. From FIG. 6, when the film thickness d1 of the adhesive sheet 24 is 30 μm, the surface areas S of the electrodes 6 and 7 are 30 mm × 30 mm (denoted as √S = 30 mm in FIG. 6), and the distances L between the electrodes are 20 mm and 30 mm. In the batteryless electronic device 20, the IC tags operated in all five prepared devices, and the operating rate was 100%. Further, in the batteryless electronic device 20 in which the surface area S of the electrodes 6 and 7 is 20 mm × 20 mm (indicated as √S = 20 mm in FIG. 6) but the distance L between the electrodes is 30 mm, the IC tags are attached to all five prepared. It worked and the operating rate was 100%.

From FIG. 6, in order to improve the operating rate of the batteryless electronic device 20, it is preferable to increase the surface area S of the electrodes 6 and 7 and increase the distance L between the electrodes, but the thickness d1 of the adhesive sheet 24 If the electrodes 6 and 7 can be provided so that the air layer is not formed between the electrodes 6 and 7 and the flat plate material 101, the electronic element 8 can be provided even if the surface area S of the electrodes 6 and 7 is small, 400 mm ² or less. It was confirmed that it could be operated. Further, if the electrodes 6 and 7 can be provided so that the film thickness d1 of the sticking sheet 24 is thinned and the air layer is not formed between the adhesive sheet 24 and the flat plate material 101, the distance L between the electrodes can also be set to the electrodes 6 and 6. Although it depends on the surface area S of 7, it was confirmed that the electronic element 8 can be operated even with 10 mm of 30 mm or less.

Further, by analyzing the result of this verification test, when the film thickness d of the polymer nanosheet 10 is 3 μm, which is 1/10 of the film thickness d1 of the adhesive sheet 24, the electrodes 6 and 7 also the surface area S as 10 mm ² or more 100 mm ² or less, the thickness d1 of the sticking sheet 24 is found to be secured to the same electrostatic capacitance as that in the 30 [mu] m.

Further, by analyzing the result of this verification test, when the film thickness d of the polymer nanosheet 10 is 3 μm, which is 1/10 of the film thickness d1 of the adhesive sheet 24, the electrodes 6 and 7 It was found that by adjusting the surface area S, even if the distance L between the electrodes is 2 mm or more and 10 mm or less, the same capacitive impedance as when the film thickness d1 of the adhesive sheet 24 is 30 μm can be secured.

(5-3) Operating rate of the batteryless electronic device when the film thickness of the adhesive sheet is changed Next, the operating rate of the batteryless electronic device 20 changes when the film thickness d1 of the adhesive sheet 24 is changed. I confirmed whether or not to do it. Here, five batteryless electronic devices 20 are prepared in which the surface area S of the square electrodes 6 and 7 is 20 mm × 20 mm, the distance between the electrodes L is 30 mm, and the film thickness d1 of the sticking sheet 24 is 30 μm. Separately from this, five batteryless electronic devices 20 each having the surface area S of the electrodes 6 and 7 and the distance L between the electrodes the same as above and the film thickness d1 of the adhesive sheet 24 being 100 μm and 170 μm, respectively. I prepared it. Here, the film thickness d of the single polymer nanosheet 10 is set to 800 nm, and the film thickness d1 of the adhesive sheet 24 is adjusted by changing the film thickness of the support substrate 23.

Next, in order to reproduce the state in which the batteryless electronic device 20 is attached to the human body 100, a plurality of rubber flat plates 101 are prepared as a skin model in the same manner as in the above-mentioned verification test, and each flat plate 101 is prepared. The batteryless electronic device 20 was attached to the surface of the flat plate material 101.

Then, as in the above-mentioned verification test, a commercially available eNFC starter kit (manufactured by eNFC Co., Ltd.) is used to operate the reader / writer of the eNFC starter kit, and each flat plate material is attached to the electric field antenna 102 connected to the reader / writer. The back surface of 101 was brought into contact.

At this time, it was confirmed whether or not the IC tag of the batteryless electronic device 20 attached to the surface of each flat plate member 101 operates by the electric field generated by the electric field antenna 102. As a result, the result shown in FIG. 7 was obtained. From FIG. 7, it was confirmed that the operating rate of the batteryless electronic device 20 was 100% when the film thickness d1 of the sticking sheet 24 was 30 μm, but the operating rate decreased as the film thickness d1 increased. ..

Therefore, in order to improve the operating rate of the batteryless electronic device 20, it was confirmed that it is desirable to reduce the film thickness d1 of the sticking sheet 24 of the batteryless electronic device 20.

(6) Other Embodiments The present invention is not limited to the present embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, in the above-described embodiment, the batteryless electronic devices 3 and 20 provided with the two electrodes 6 and 7 have been described, but the present invention is not limited to this, and two or more such as three or four. It may be a batteryless electronic device provided with electrodes. Further, as long as the batteryless electronic device attached to the transmission medium can operate when the transmission medium comes into contact with the transmission device 2, for example, a device other than the human body 100 such as a device or an animal may be applied as the transmission medium.

Further, in the above-described embodiment, when the transmission medium comes into contact with the transmission device 2, the coil of the transmission device 2 and the capacitor formed between the transmission medium and the electrodes 6 and 7 are connected in series for transmission. Although the case where the series resonance method in which the batteryless electronic device 3 is resonated at the frequency of the device 2 is applied has been described, the present invention is not limited to this. For example, the transmission device 2 and the batteryless electronic device 3 are provided with a transformer-coupled parallel resonance circuit, respectively, and the power to the batteryless electronic device 3 is supplied even if the electrostatic coupling between the transmission medium and the electrodes 6 and 7 is small. A parallel resonance method capable of supplying may be applied, or a method in which these series resonance method and the parallel resonance method are combined may be applied.

Further, the materials of the polymer nanosheet 10 and the second polymer nanosheet 11 are not limited to those exemplified in the above-described embodiment, and the polymer nanosheet 10 that can be attached to a transmission medium such as the human body 100 by intermolecular force, or Any second polymer nanosheet 11 that can be attached to the polymer nanosheet 10 by intermolecular force may be used, and various materials can be applied.

Further, if the materials of the electrodes 6 and 7 and the material of the wiring 9 are also conductive materials and can be brought into close contact with the transmission medium via the flexible polymer nanosheet 10, various materials and shapes can be obtained. Applicable. Further, the method of forming the electrodes 6 and 7 and the wiring 9 is not limited to the one formed by printing.

Further, in the above-described embodiment, the second polymer nanosheet 11 is attached onto the polymer nanosheet 10, and the electrodes 6 and 7, the electronic element 8 and the wiring 9 are attached to the polymer nanosheet 10 and the second polymer. The case where the batteryless electronic device 3 sandwiched between the nanosheet 11 and the nanosheet 11 is applied has been described, but the present invention is not limited to this. For example, a batteryless electronic device in which the electrodes 6 and 7, the electronic element 8 and the wiring 9 are simply provided on the polymer nanosheet 10 without providing the second polymer nanosheet 11 may be used.

1 Transmission system 2 Transmission device 3,20 Batteryless electronic device 6,7 Electrode 8 Electronic element 9 Wiring 10 Polymer nanosheet 11 Second polymer nanosheet 100 Human body (transmission medium)

Claims (8)

With electronic devices
With at least two or more electrodes electrically connected to the electronic element,
A polymer nanosheet that adheres to the transmission medium and attaches the electrode to the transmission medium,
With
A batteryless electronic device in which electric power is supplied to the electronic element by electrostatic coupling between the transmission medium and the electrode based on an electric field induced in the transmission medium from the outside. The batteryless electronic device according to claim 1, wherein the transmission medium is a human body, and the polymer nanosheets follow the surface shape of the skin of the human body and are adhered to the skin by intermolecular force. The batteryless electronic device according to claim 1 or 2, wherein the wiring connecting the electrode and the electronic element and the electrode are formed of conductive ink. A claim that a second polymer nanosheet is attached onto the polymer nanosheet, and the electronic element and the electrode are sandwiched between the polymer nanosheet and the second polymer nanosheet. Item 3. The batteryless electronic device according to any one of Items 1 to 3. The batteryless electronic device according to any one of claims 1 to 4, wherein the polymer nanosheet has a thickness of less than 2 μm. The batteryless electronic device according to any one of claims 1 to 5, wherein the surface area S of the electrode attached to the transmission medium is 400 mm ² or less. The batteryless electronic device according to any one of claims 1 to 6, wherein the distance L between the first electrode and the second electrode is 30 mm or less. A transmission system including a transmission device installed at a predetermined location to generate an electric field and a batteryless electronic device provided in a transmission medium.
The batteryless electronic device is
The batteryless electronic device according to any one of claims 1 to 7.
A transmission system in which power is supplied to an electronic element by electrostatic coupling between the transmission medium and an electrode based on an electric field induced in the transmission medium when the transmission medium comes into contact with the transmission device.

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