JP7201137B2 - Container with RFID module - Google Patents

Description

TECHNICAL FIELD The present invention relates to a container provided with an RFID module, and more particularly to a container provided with an RFID module using RFID (Radio Frequency Identification) technology for non-contact data communication using an induced electromagnetic field or radio waves.

Conventionally, it has been considered to manage products in a container by attaching an RFID tag, which is a wireless communication device, to the container. An RFID tag, together with an RFIC (Radio-Frequency Integrated Circuit), has a metal material such as an antenna pattern formed on an insulating substrate such as a paper material or a resin material. However, if a metal film is formed on the outer surface of the container, the RFID tag is affected and communication becomes impossible.

In a container with an RFID tag as described above, Patent Literature 1 proposes a configuration in which an RFID tag is provided that is compatible with metal formed on a part of the container so as not to impair the design.

International Publication No. 2019-039484

The RFID tag disclosed in Patent Document 1 has an RFIC chip and an antenna pattern, and a metal film cannot be formed on the container in these regions. Therefore, there is a demand for a container having an RFID module that suppresses a reduction in the degree of design freedom.

SUMMARY OF THE INVENTION An object of the present invention is to provide a container having a metal film formed thereon and having an RFID module that suppresses deterioration in design.

A container of one embodiment of the present invention is a container comprising an RFID module, comprising an insulating base forming the outer shape of the container, a metal film formed on the base, and a region in which the metal film is formed. and a slot formed on a base material, the RFID module includes an RFIC element, a filter circuit for transmitting a current due to electromagnetic waves having a unique resonance frequency that is a communication frequency to the RFIC element, and a second filter circuit connected to the RFIC element. 1 and a second electrode, the first electrode of the RFID module and the metal film are electrically connected, and the RFID module straddles the slot and the second electrode of the RFID module and the metal film are electrically connected be.

ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide a container having an RFID module that suppresses deterioration of design in a container on which a metal film is formed.

1 is an overall perspective view of a container having an RFID module according to Embodiment 1; FIG. II-II arrow sectional view in FIG. An exploded view of the container in FIG. Perspective plan view of RFID module Cross-sectional view of arrow V in FIG. FIG. 6A is a plan view of a conductor pattern formed on the substrate of the RFID module; FIG. 6B is a plan view of the conductor pattern formed on the bottom surface of the substrate; perspective plan view from above Sectional view of arrow VII in FIG. Equivalent circuit diagram of RFID module The whole perspective view of the container in the modification of Embodiment 1. The whole perspective view of the container in the modification of Embodiment 1. FIG. 4 is a development view of a container in a modified example of Embodiment 1. FIG. Cross-sectional view of a container in a modified example of Embodiment 1 FIG. 11 is a cross-sectional view in which the containers of the modified example of the first embodiment are stacked and arranged; The whole perspective view of the container in the modification of Embodiment 1. Sectional view of the RFID module in the modified example of the first embodiment FIG. 4 is a development view of a container in a modified example of Embodiment 1. FIG. FIG. 4 is a development view of a container in a modified example of Embodiment 1. FIG. FIG. 4 is a development view of a container in a modified example of Embodiment 1. FIG. The whole perspective view of the container in the modification of Embodiment 1. FIG. 11 is a cross-sectional view in which the containers of the modified example of the first embodiment are stacked and arranged; The whole perspective view of the container in the modification of Embodiment 1. The whole perspective view of the container in the modification of Embodiment 1. The whole perspective view of the container in the modification of Embodiment 1. Graph showing communication characteristics of the RFID module of Embodiment 2

A container according to one aspect of the present invention is a container provided with an RFID module, comprising: an insulating base forming the outer shape of the container; a metal film formed on the base; a slot formed on a substrate in the RFID module, the RFID module is connected to the RFIC element, a filter circuit for transmitting a current due to electromagnetic waves having a unique resonance frequency, which is the communication frequency, to the RFIC element, and the filter circuit. and a first electrode and a second electrode, wherein the first electrode of the RFID module and the metal film are electrically connected, and the RFID module straddles the slot and the second electrode of the RFID module and the metal film are electrically connected. be done.

Since the container of this aspect uses the metal film formed on the base material of the container as an antenna, the RFID module can be attached to the container while suppressing the reduction in the degree of freedom of design in the container on which the metal film is formed. can be done.

Further, when the metal film is irradiated with the electromagnetic wave of the communication frequency, the current may flow in the direction of circling the slot. In this way, the metal film functions as a slot antenna, so communication characteristics of a slot antenna can be obtained.

The length of the slot may have the physical length of one-half wavelength of an electromagnetic wave at the communication frequency. In this case, the maximum communication distance as a slot antenna is often obtained.

A container with an RFID module can be a modular box.

The sides of the box may have recesses extending longitudinally of the sides, with slots formed in the recesses. As a result, even if a plurality of containers are arranged in the same direction, the slots and metal films are prevented from contacting each other, and the slots can be short-circuited by the metal films of other containers and conduct without passing through the RFID module. Absent. Therefore, it is possible to communicate with multiple containers at once. In addition, since the concave portion is formed, a gap is formed between the containers when the containers are arranged, and electromagnetic waves for communication are easily transmitted.

A slot may be formed in a corner between the first side and the second side of the box.

The slot may be formed in a taper formed between the first side and the second side of the box. As a result, even if a plurality of containers are arranged in the same direction, the slots and metal films are prevented from contacting each other, and the slots can be short-circuited by the metal films of other containers and conduct without passing through the RFID module. Absent. Therefore, it is possible to communicate with multiple containers at once. In addition, since the tapered portion is formed, a gap is formed between the containers when the containers are arranged, and electromagnetic waves for communication are easily transmitted.

The metal film may be formed on the entire surface of the substrate except for the slots. It is also possible to realize a design in which a metal film is formed on the entire outer surface of the container.

The filter circuit may be an LC parallel resonant circuit. As a result, a current with a frequency that matches the RFIC can be passed through the RFIC.

The filter circuit has a coil formed on the substrate, and the coil may be covered with a protective layer. Thereby, the dielectric constant of the coil can be fixed, and the influence of the dielectric inside the container can be prevented.

The coils of the filter circuit may have a figure eight shape. This makes it difficult for the magnetic field of the coil to leak to the outside, and makes it difficult for the inductance value of the coil to change due to external factors.

The sheet resistance of the metal film may be 0.5Ω/□ or more. Even with this configuration, since the RFID module has a filter circuit, the eddy current generated in the metal film can be utilized to flow to the RFIC.

The thickness of the metal film may be 1 nm or more and 1 μm or less. Even with this configuration, since the RFID module has a filter circuit, the eddy current generated in the metal film can be utilized to flow to the RFIC.

It should be noted that each embodiment described below is one specific example of the present invention, and the present invention is not limited to this configuration. Numerical values, shapes, configurations, steps, order of steps, and the like specifically shown in the following embodiments are examples and do not limit the present invention. Among the constituent elements in the following embodiments, constituent elements that are not described in independent claims indicating the highest concept will be described as optional constituent elements. Moreover, in all the embodiments, the configuration in each modification is the same, and the configurations described in each modification may be combined.

When the dielectric constant εr>1, the electrical lengths of the antenna pattern and conductor pattern are longer than their physical lengths. In this specification, the electrical length is a length that takes into account wavelength shortening or extension due to relative permittivity and parasitic reactance components.

(Embodiment 1)
Next, a schematic configuration of the container 1 having the RFID module 5 according to the present invention will be described. FIG. 1 is an overall perspective view of a container 1 having an RFID module 2 according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along the line II--II in FIG. 1, and FIG. 3 is a developed view of the container 1 in FIG.

The container 1 of Embodiment 1 includes a base material 3, an RFID module 5 attached to the base material 3, a metal film 7 formed on the first main surface 3s of the base material 3, and a metal film 7 formed in the metal film 7. and a slot 9 with a .

The container 1 is, for example, a prefabricated box that is formed into a three-dimensional shape by assembling planar substrates 3 as shown in FIG. The container 1 has, for example, a cuboid shape, and the substrate 3 is made from, for example, paper, resin, or plastic.

The base material 3 has a first surface 3a, a second surface 3b, a third surface 3c, a fourth surface 3d, a fifth surface 3e, a sixth surface 3f, and a first flap 3g, a second flap 3h, and a third flap. 3k. For example, the first surface 3a to the fourth surface 3d become side surfaces when assembled, the fifth surface 3e becomes the upper surface when assembled, and the sixth surface 3f becomes the lower surface when assembled. The first main surface 3 s of the base material 3 is the outer surface (front surface) of the container 1 , and the second main surface 3 t of the base material 3 is the inner surface (back surface) of the container 1 .

The first main surface 3s of the first flap 3g is attached to the second main surface 3t of the second surface 3b via an adhesive layer (not shown) when assembled. The first main surface 3s of the second flap 3h is attached to the second main surface 3t of the first surface 3a via an adhesive layer when assembled. The first main surface 3s of the third flap 3k is attached to the second main surface 3t of the first surface 3a via an adhesive layer when assembled.

The metal film 7 is formed on the entire first main surface 3s of the base material 3 except for the slots 9. As shown in FIG. The metal film 7 is made of a film body made of a conductive material such as a metal foil such as an aluminum foil or a copper foil, and is formed, for example, by attaching a metal sheet. A communication distance can be increased by using a metal having a low resistance value, such as aluminum or copper, as the metal film 7 . The thickness of the metal film 7 is, for example, greater than 5 μm and equal to or less than 40 μm. The metal film 7 may not be formed on the entire surface of the base material 3, and may be partially formed on, for example, the third surface 3c on which the slots 9 are formed and other surfaces.

When the length Lg of the slot 9 is half the wavelength of the electromagnetic wave of the communication frequency, the communication distance is maximized. When the container 1 is irradiated with an electromagnetic wave having a communication frequency, communication is performed in a direction circulating the slot 9 so as to reciprocate from the RFID module 5 positioned at the center of the slot 9 in the longitudinal direction to the ends of the two slots 9 respectively. It resonates with the frequency and current Ir flows (see FIG. 1).

Slot 9 is a groove formed in the area of metal film 7 . The width W of the slot 9 is, for example, 1 mm. The slot 9 may be formed by forming the metal film 7 on the entire first main surface 3s of the base material 3 and then scraping the metal film 7 with, for example, sandpaper. It may be formed by affixing to the first main surface 3S of the base material 3 with a width of 9 left. In addition, the slot 9 may be formed not only on the third surface 3c of the base material 3 but also on another surface.

The RFID module 5 of Embodiment 1 is a wireless communication device configured to wirelessly communicate (transmit and receive) using high-frequency signals having a communication frequency (carrier frequency). The RFID module 5 is configured, for example, to wirelessly communicate with a high-frequency signal having a frequency for UHF band communication. Here, the UHF band is a frequency band from 860 MHz to 960 MHz.

Next, the configuration of the RFID module 5 will be described with reference to FIGS. 4 to 7. FIG. 4 is a perspective plan view of the RFID module, and FIG. 5 is a cross-sectional view taken along arrow V in FIG. 6 shows a plan view of the conductor pattern formed on the substrate of the RFID module, FIG. 6a is a plan view of the conductor pattern formed on the upper surface of the substrate of the RFID module, and FIG. 6b is a plan view of the conductor pattern formed on the lower surface of the substrate. 1 is a perspective plan view of a conductor pattern seen from above; FIG. 7 is a cross-sectional view taken along line VII in FIG. 4. FIG. In the drawings, the XYZ coordinate system is intended to facilitate understanding of the invention and is not intended to limit the invention. The X-axis direction indicates the longitudinal direction of the RFID module 5, the Y-axis direction indicates the depth (width) direction, and the Z-axis direction indicates the thickness direction. The X, Y and Z directions are orthogonal to each other.

As shown in FIG. 4, the RFID module 5 is attached across the slot 9 to the upper surface of the metal film 7 via a double-sided tape or an adhesive 15 such as synthetic resin.

As shown in FIG. 5 , the RFID module 5 includes a substrate 21 and an RFIC 23 mounted on the substrate 21 . The substrate 21 is, for example, a flexible substrate such as polyimide. A protective film 25 is formed on the upper surface of the substrate 21 on which the RFIC 23 is mounted. The protective film 25 is, for example, an elastomer such as polyurethane or a hot melt agent such as ethylene vinyl acetate (EVA). A protective film 27 is also attached to the lower surface of the substrate 21 . The protective film 27 is, for example, a coverlay film such as a polyimide film (Kapton tape).

Please refer to FIG. A third electrode 33, a fourth electrode 35, a conductor pattern L1a of the main portion of the first inductance element L1, and a conductor pattern L2a of the main portion of the second inductance element L2 are formed on the upper surface of the substrate 21. FIG. The third electrode 33 is connected to one end of the conductor pattern L1a, and the fourth electrode 35 is connected to one end of the conductor pattern L2a. These conductor patterns are obtained by patterning copper foil by photolithography, for example.

A first electrode 29 and a second electrode 31 capacitively coupled to the metal film 7 are formed on the lower surface of the substrate 21 . Further, on the lower surface of the substrate 21, a conductor pattern L1b, which is a part of the first inductance element L1, and conductor patterns L3a, L3b (a conductor pattern surrounded by a two-dot chain line), and L3c of the third inductance element L3 are formed. These conductor patterns are also obtained by patterning copper foil by photolithography, for example.

One end of the conductor pattern L1b of the first inductance element L1 and one end of the conductor pattern L3a of the third inductance element L3 are connected to the first electrode 29 . Similarly, one end of the conductor pattern L2b of the second inductance element L2 and one end of the conductor pattern L3c of the third inductance element L3 are connected to the second electrode 31 . A conductor pattern L3b is connected between the other end of the conductor pattern L3a of the third inductance element L3 and the other end of the conductor pattern L3c.

The other end of the conductor pattern L1b of the first inductance element L1 and the other end of the conductor pattern L1a of the first inductance element L1 are connected via a via conductor V1. Similarly, the other end of the conductor pattern L2b of the second inductance element L2 and the other end of the conductor pattern L2a of the second inductance element L2 are connected via a via conductor V2.

The RFIC 23 is mounted on the third electrode 33 and the fourth electrode 35 formed on the upper surface of the substrate 21 . That is, the terminal 23 a of the RFIC 23 is connected to the third electrode 33 and the terminal 23 b of the RFIC 23 is connected to the fourth electrode 35 .

The conductor patterns L3a of the first inductance element L1 and the third inductance element L3 are formed in different layers of the substrate 21, respectively, and arranged such that their coil openings overlap each other. Similarly, the conductor patterns L3c of the second inductance element L2 and the third inductance element L3 are formed in different layers of the substrate 21, respectively, and arranged such that their coil openings overlap. Further, the RFIC 23 is positioned between the conductor pattern L3c of the second inductance element L2 and the third inductance element L3 and the conductor pattern L3a of the first inductance element L1 and the third inductance element L3 on the surface of the substrate 21. do. The conductor patterns L1a, L1b, and L3a form a first coil Cr1, and the conductor patterns L2a, L2b, and L3c form a second coil Cr2.

In the RFID module 5, a first current path CP1 passing through the top and bottom surfaces of the substrate 21 and a second current path CP2 passing through the bottom surface of the substrate 21 are formed. The first current path CP1 extends from the first electrode 29 to the second electrode 31 through the branch point N1, the conductor pattern L1b, the conductor pattern L1a, the RFIC 23, the conductor pattern L2a, the conductor pattern L2b, and the branch point N2. The second current path CP2 extends from the first electrode 29 to the second electrode 31 through the branch point N1, the conductor pattern L3a, the conductor pattern L3b, the conductor pattern L3c, and the branch point N2. Here, the first inductance element L1 is composed of the conductor pattern L1b connected to the conductor pattern L1a via the via conductor V1, and the conductor pattern L2b is composed of the conductor pattern L2a connected to the conductor pattern L2a via the via conductor V2. The winding direction of the current flowing through the second inductance element L2 is reversed, and the magnetic field generated by the first inductance element L1 and the magnetic field generated by the second inductance element L2 cancel each other. The first current path CP1 and the second current path CP2 are formed in parallel with each other between the first electrode 29 and the second electrode 31, respectively.

Conventionally, when a slot antenna is provided in a container, the slot antenna may be affected by the contents in the container and communication may be hindered. This is because the physical length of the slot is fixed, and if the electrical length of the slot is affected and changed by contents such as liquid, communication may not be possible. Therefore, the slot antenna is not suitable as an antenna formed in the container.

When a dielectric such as a liquid is contained in the container, the dielectric constant of the RFID tag changes and the electrical length of the slot becomes shorter than half the wavelength of the electromagnetic wave of the communication frequency. In addition, the change in permittivity also changes depending on the distance between the contents and the slot antenna. Therefore, the communication characteristics change as the position of the contents changes within the box.

In the first embodiment, in order to avoid the wavelength change (frequency change) due to the change in the dielectric constant, the frequency design is not based on the length of the slot 9, but the resonance frequency is fixed by the RFID module 5. It can handle frequency changes due to length.

Further, the RFIC 23 is a small chip, and coil patterns are wound so that the first coil Cr1 and the second coil Cr2 having a laminated structure cancel out the magnetic field. As a result, the periphery of the RFIC 23 is fixed at the dielectric constant of the RFID module 5 and is not affected by the dielectric (contents) accommodated in the container 1, so the frequency matching the RFIC 23 does not change. Referring to FIG. 7, the dielectric constant of the substrate 21 between the conductor patterns L1a, L2a and the conductor patterns L3a, L3c is fixed, and there is no change in line-to-line capacitance. Also, the conductor patterns L1a and L2a and the conductor patterns L3a and L3c are covered with a protective film 25 and a protective film 27 as protective layers with a fixed dielectric constant, respectively. Thus, the permittivity of the RFID module 5 is fixed.

Further, in order to reduce the influence of the dielectric constant of the dielectric inside the container 1, the first coil Cr1 and the second coil Cr2 of the RFID module 5 form a figure-of-eight coil. is difficult to leak to the outside. Since the magnetic field of the RFID module 5 hardly leaks, the inductance value does not easily change due to external factors.

Further, since the magnetic flux of the RFID module 5 is also closed, even if metal is contained in the container 1, the change in frequency matching with the RFIC 23 is small.

Next, the circuit configuration of the RFID module 5 will be described with reference to FIG. FIG. 8 is an equivalent circuit diagram of the RFID module 5. As shown in FIG.

In the RFID module 5, the first current path CP1 is part of the parallel resonant circuit RC1, which is an LC parallel resonant circuit, and is matched with the radio waves of the communication frequency. is received, a current flows through the RFIC 23 .

A parallel resonant circuit RC1 is formed in the RFID module 5 . The parallel resonant circuit RC1 is a loop circuit composed of a first inductance element L1, RFIC 23, a second inductance element L2, and a third inductance element L3.

Capacitor C<b>1 is composed of metal film 7 , first electrode 29 , adhesive 15 , and protective film 27 . Capacitor C 2 is composed of metal film 7 , second electrode 31 , adhesive 15 and protective film 27 . The fourth inductance element L4 is the inductance component of one metal film 7, and the fifth inductance element L5 is the inductance component of the other metal film 7. FIG. Since the RFID module 5 is electrically coupled to the metal film 7 forming the slot 9 via the capacitors C1 and C2, the current flowing around the slot 9 will flow through both the fourth inductance element L4 of the metal film 7. , and flows into the RFID module 5 via the end of the slot 9, the fifth inductance element L5 of the other metal film 7, and the capacitor C2.

The parallel resonance circuit RC1 is designed to perform LC parallel resonance by impedance matching with respect to radio waves at a communication frequency. Thereby, the communication frequency is matched with the RFIC, and the communication distance of the RFID module 5 at the communication frequency can be secured.

As described above, the container 1 of Embodiment 1 is a container 1 equipped with an RFID module 5, and includes an insulating base material 3 forming the outer shape of the container 1 and a metal film 7 formed on the base material 3. and a slot 9 formed on the substrate 3 in the region where the metal film 7 is formed. The RFID module 5 includes an RFIC 23, a parallel resonance circuit RC1 as a filter circuit that transmits current due to electromagnetic waves having a unique resonance frequency, which is a communication frequency, to the RFIC 23, and a first electrode 29 and a second electrode connected to the parallel resonance circuit RC1. 31 and. The first electrode 29 of the RFID module 5 and the metal film 7 are electrically connected, and the second electrode 31 of the RFID module 5 and the metal film 7 are electrically connected with the RFID module 5 straddling the slot 9 .

Since the RFID module 5 is arranged straddling the slot 9 formed in the metal film 7 formed on the base material 3 of the container 1, the slot 9 can be used as a slot antenna, and the current is transmitted to the RFIC 23 by series resonance. can flow. Therefore, even the container 1 having the metal film 7 formed thereon can perform wireless communication, and can provide the container 1 having the RFID module 5 that suppresses deterioration of the design. In addition, the container 1 of the first embodiment can be provided at a lower cost than a conventional container equipped with a metal RFID module.

When the metal film 7 is irradiated with an electromagnetic wave having a communication frequency, a current flows in a direction circulating the slot 9 . Since the metal film 7 around the slot 9 thus functions as a slot antenna, the container 1 can obtain communication characteristics as a slot antenna.

Also, the length of the slot 9 has a physical length of half the wavelength of the electromagnetic wave of the communication frequency. As a result, the maximum communication distance as a slot antenna is often obtained.

The metal film 7 is formed on the entire first main surface 3s of the base material 3 except for the slots 9. As shown in FIG. In this way, a design in which the metal film 7 is formed over the entire first main surface 3s of the container 1 can also be realized.

Next, Modification 1 of Embodiment 1 will be described with reference to FIG. FIG. 9 is an overall view of a container 1A in Modification 1 of Embodiment 1. FIG. A container 1A in Modification 1 of Embodiment 1 has a configuration in which the slot 9 of the container 1 of Embodiment 1 is formed over the second surface 3b and the third surface 3c. Thus, the slot 9 may extend over multiple sides in a laterally circumferential direction around the container 1A. Other configurations of Modification 1 of Embodiment 1 are substantially the same as those of container 1 of Embodiment 1. FIG.

Next, Modification 2 of Embodiment 1 will be described with reference to FIGS. 10 and 11. FIG. FIG. 9 is an overall view of a container 1B in Modification 2 of Embodiment 1. FIG. FIG. 10 is a developed view of the container 1B in Modification 2 of Embodiment 1. FIG. A container 1B according to Modified Example 2 of Embodiment 1 has a configuration in which the slot 9 of the container 1 of Embodiment 1 is formed along the long side of the third surface 3c. Other configurations of Modification 2 of Embodiment 1 are substantially the same as those of container 1 of Embodiment 1. FIG.

In the container 1B according to Modification 2, as shown in FIG. 10, the electric current Ir flows along the slot 9 so as to circulate, and power is supplied to the RFID module 5. As shown in FIG. Part of the current Ir passes through the fifth surface 3e and the sixth surface 3f.

Also, the third surface 3c may have a vertically extending recess 3v as shown in FIG. FIG. 12 is a cross-sectional view of a container 1C according to Modification 3 of Embodiment 1. FIG. Other configurations of the third modification of the first embodiment are substantially the same as the container 1 of the first embodiment. The metal film 7 is also formed along the recess 3v, and the slot 9 is formed at the bottom of the recess 3v.

As shown in FIG. 13, the container 1C has a concave portion 3v extending in the longitudinal direction on the third surface 3c, which is the side surface of the container 1C. Since the metal film 7 of the other container 1c does not come into contact with the slot 9, the slot 9 is not short-circuited. Therefore, by simply arranging the containers 1C at the same height, it is possible to collectively perform wireless communication with a plurality of containers 1C. Further, since the concave portion 3v is formed, a gap is formed between the containers 1C when the containers 1C are arranged, and electromagnetic waves for communication are easily transmitted.

Also, as shown in FIG. 14A, slots 9 may be formed at the corners between one side and the other side of the box. For example, a slot 9 is formed at the corner between the second surface 3b and the third surface 3c. By making a cut reaching the second surface 3b and the third surface 3c in the unfolded state of the box-shaped container 1D, this cut becomes a slot 9 when the container 1D is assembled. When the RFID module 5 is composed of a flexible member as shown in FIG. 14B, the RFID is generated starting from between the inner ends of the metal film 7, the first electrode 29 and the second electrode 31 and the conductor pattern L3b. By bending the module 5, the portions of the first electrode 29 and the second electrode 31 used for capacitive coupling at both ends of the RFID module 5 can be arranged on a plane different from that of the RFIC 23, following the corners of the container 1D. In addition, when the container 1D is in an unfolded state and attached to the metal film 7 across the gap that becomes the slot 9, communication with the RFID module 5 cannot be performed because the gap is closed and the slot 9 is short-circuited. However, when the container 1D is assembled, the slot 9 is formed so that the RFID module 5 can communicate. Therefore, by communicating with the RFID module 5, it is possible to determine whether or not the assembly of the box-shaped container 1D is completed.

Next, Modification 4 of Embodiment 1 will be described with reference to FIG. FIG. 15 is a developed view of the container 1E in Modification 4 of Embodiment 1. FIG. In the container 1E according to Modification 4 of Embodiment 1, in the container 1 of Embodiment 1, the shape of the slot 9 is not linear but wavy. Even with such a configuration, the communication characteristics are not changed, so the container 1E of the fourth modification of the first embodiment can obtain the same effect as the container 1 of the first embodiment.

Next, Modification 5 of Embodiment 1 will be described with reference to FIG. FIG. 16 is a developed view of the container 1F in Modification 5 of Embodiment 1. FIG. In the container 1F according to Modification 5 of Embodiment 1, in the container 1 of Embodiment 1, the shape of the slot 9 is not linear but wavy. Furthermore, both ends of the slot 9 are rectangular with a planar spread. As described above, even if the slot 9 has a combination of a waveform shape and a rectangular shape, the communication characteristics are not changed. A similar effect can be obtained.

Next, Modification 6 of Embodiment 1 will be described with reference to FIG. FIG. 17 is an exploded view of the container 1G in Modification 6 of Embodiment 1. FIG. In the container 1G according to Modification 6 of Embodiment 1, in the container 1 of Embodiment 1, the slot 9 extends in the vertical direction while being inclined with respect to the long side of the third surface 3c, which is the side surface, and both ends of the container 1G extend vertically. It bends and extends along the short sides of the three surfaces 3c. Even with such a shape of the slot 9, the communication characteristics are not changed.

Next, Modification 7 of Embodiment 1 will be described with reference to FIG. FIG. 18 is an overall perspective view of a container 1H according to Modification 7 of Embodiment 1. FIG. A container 1H according to Modified Example 7 of Embodiment 1 has, in the container 1 of Embodiment 1, a tapered portion 3u with a rounded corner between the second surface 3b and the third surface 3c. It is a configuration in which a slot 9 is formed. A metal film 7 is continuously formed at the end portion in the width direction of the tapered portion 3u. Therefore, it is also possible to arrange the RFID module 5 on the tapered portion 3u without bending it.

FIG. 19 shows a cross-sectional view in which the containers 1H of Modification 7 of Embodiment 1 are stacked and arranged. Since the slot 9 is formed in the tapered portion 3u of the container 1H, even if a plurality of containers 1H are arranged in contact with each other, the metal film 7 of another container 1H may contact the slot 9 of the tapered portion 3u. Absent. As a result, the slots 9 of the container 1H are not short-circuited. Therefore, it is possible to perform wireless communication with a plurality of containers 1H collectively only by arranging the containers 1H at the same height. Moreover, since the tapered portion 3u is formed in the container 1H, a gap is formed between the containers 1H when the containers 1H are arranged, and electromagnetic waves for communication are easily transmitted.

Next, Modification 8 of Embodiment 1 will be described with reference to FIG. FIG. 20 is an overall perspective view of a container 1K in Modification 8 of Embodiment 1. FIG. A container 1K in Modification 8 of Embodiment 1 has a configuration in which two crossing slots 9 are provided in the container 1 of Embodiment 1. As shown in FIG. Other configurations are substantially the same as the container 1 of the first embodiment. An RFID module 5 is arranged at the intersection of the intersecting slots 9 . In this way, the slot 9 can improve the design flexibility of the container 1H. Moreover, as shown in FIGS. 20 and 21, the RFID modules 5 are arranged in the intersecting slots 9 so that the current flows in the horizontal direction of the container 1K, and in the vertical direction. Since the RFID module 5 can be arranged in two patterns, the communication characteristics of the RFID module 5 can be selected.

In the case of the container 1K shown in FIG. 20, the RFID module 5 uses the first area 3ca and the second area 3cb on the third surface 3c as radiation areas. On the other hand, in the case of the container 1K shown in FIG. 21, the RFID module 5 uses the third area 3cc and the fourth area 3cd on the third surface 3c as radiation areas.

Next, Modification 9 of Embodiment 1 will be described with reference to FIG. FIG. 22 is a developed view of the container 1L in Modification 9 of Embodiment 1. FIG. A container 1L according to the ninth modification of the first embodiment is different from the container 1L of the ninth modification of the first embodiment in that a slot 9 is formed on the fifth surface 3e, which is the upper surface. Thus, even if the RFID module 5 is arranged on the upper surface of the container 1, the communication characteristics do not change. can be obtained.

(Embodiment 2)
A container 1 according to Embodiment 2 of the present invention will be described below.

The difference between the container 1 of Embodiment 2 and the container 1 of Embodiment 1 is the difference in sheet resistance of the metal film 7 . This difference will be mainly described below. In the description of the second embodiment, descriptions of elements having the same configurations, actions, and functions as those of the first embodiment may be omitted in order to avoid overlapping descriptions. The container 1 of Embodiment 2 has the same configuration as the RFID module 5 of Embodiment 1 except for the points described below.

The sheet resistance of the metal film 7 of the container 1 of the second embodiment is higher than the sheet resistance of the metal film 7 of the container 1 of the first embodiment. When the sheet resistance of the metal film 7 is large, the following problem occurs, which did not occur in the container 1 of the first embodiment.

In the container 1 of Embodiment 1, the entire metal film 7 around the slot 9 as an antenna electrode causes a resonance phenomenon to radiate electromagnetic waves. The thickness of the metal film 7 in Embodiment 1 is, for example, greater than 5 μm and 40 μm or less, and the sheet resistance of the metal film 7 is 0.05Ω/□ or less.

The metal film of the container is usually formed to prevent food oxidation and improve design. Furthermore, if the design is printed by gravure printing, offset printing, or the like, the printing thickness will be about 1 μm. In this case, a difference in level occurs in the printed matter due to the thickness of the metal film as the antenna foil, which causes printing misalignment (blurring or bleeding). For these reasons, it has not been possible to directly print a design on a container to which a conventional antenna foil is attached.

When a metal film as an antenna is formed by vapor deposition, the thickness of the metal film is even smaller, about 10 Å (=1 nm) to 10000 Å (=1 μm). If the metal film is of this thickness, even if gravure printing is performed on it, print bleeding due to steps will not occur. Sheet resistance increases, for example, about 0.5Ω to 50Ω/□.

If the sheet resistance of the metal film increases, even if a series resonance phenomenon that creates a standing wave occurs in the entire antenna electrode of the metal film, the radiated power will be mostly heat due to the resistance of the metal foil. cannot be done.

In addition, since the resistance value of the matching circuit section between the RFIC and the antenna has the same thickness as the metal film, the resistance value of the matching circuit section increases, the matching loss increases, and the RFID module does not operate.

In this way, an antenna electrode made of a thin metal film cannot emit electromagnetic waves due to a (series) resonance phenomenon. to shield. This current is also called eddy current. When the eddy current flows, the current component flowing in the metal film is not due to the resonance phenomenon of the antenna electrode, so it can handle all frequency components regardless of the electrode pattern shape. This eddy current is known as an effect of metal shielding, but it is not commonly used as an antenna.

Since the RFID module 5 has a parallel resonance circuit RC1 as a filter circuit that transmits only a current of a unique resonance frequency to the RFIC 23, the eddy current is frequency-selected, current flows through the RFIC 23, and energy is transmitted. Only a specific frequency is selected between the metal film 7 as the antenna electrode and the RFID module 5, impedance matching is achieved, and energy transmission between the RFIC 23 and the metal film 7 becomes possible. In this way, it is considered that communication with the RFIC 23 becomes possible.

Therefore, with the container 1 of Embodiment 2, even when the sheet resistance of the metal film 7 is high, it is possible to enable communication by using eddy current, which has not been used conventionally.

FIG. 23 is a graph showing communication characteristics of the container 1 having the RFID module 5 according to the second embodiment. Even in the UHF band from 830 MHz to 960 MHz, it has a communication range of 100 cm or more, and in particular, has a communication range of 200 cm or more in the range of 850 MHz to 895 MHz.

Moreover, the high sheet resistance of the metal film 7 is caused not only by the thickness of the metal film 7 but also by the manufacturing method of the metal film 7 . For example, even when the metal film 7 is formed of a conductive paste such as Ag paste, the sheet resistance may be 0.5Ω or more. Even in such a case, wireless communication can be performed with the container 1 of the second embodiment.

The present invention is not limited to the above embodiments, and can be modified as follows.

(1) In each of the embodiments described above, the container 1 is of an assembly type, but the present invention is not limited to this. The container 1 may be a bottle or a plastic bottle.

(2) In each of the above embodiments, the communication frequency band is the UHF band, but it is not limited to this. It may be configured to perform wireless communication using a high-frequency signal having a frequency (carrier frequency) for communication in the HF band. In this case, the entire length of the metal film 7 perpendicular to the slot 9 is designed to receive high frequency signals in the HF band. The HF band is a frequency band from 13 MHz to 15 MHz.

(3) In each of the embodiments described above, the RFID module 5 is attached to the metal film 7, but the present invention is not limited to this. RFIC 23 may be electrically connected to metal film 7 via an inductor. In this case, the inductor is formed on the side of the metal film 7 functioning as an antenna pattern. When the inductor is formed on the metal film 7 side, the metal film 7 may have a lower sheet resistance by attaching a metal foil as in the first embodiment.

(4) In each of the above-described embodiments, a pattern may be formed by applying paint to the area of the metal film 7 other than the area where the RFID module 5 is attached to improve the design of the container 1. . Also, the metal film 7 and the slots 9 may be formed on the second main surface 3t, which is the inner surface of the substrate 3, instead of the first main surface 3S, which is the outer surface. That is, the metal film 7 and the slot 9 may be formed inside the container 1 .

Although the present invention has been described in each embodiment with a certain degree of detail, the disclosure of these embodiments should vary in details of construction, and the combination and order of elements in each embodiment may vary. Changes may be made without departing from the scope and spirit of the claimed invention.

1 container 3 substrate 3a first surface 3b second surface 3c third surface 3ca first area 3cb second area 3cc third area 3cd fourth area 3d fourth surface 3e fifth surface 3f sixth surface 3g first flap 3h Second flap 3k Third flap 3s First main surface 3t Second main surface 3u Tapered portion 3v Recess 5 RFID module 5a Front surface 5b Back surface 7 Metal film
9 slot 15 adhesive 21 module substrate 23 RFIC
23a terminal 23b terminal 25 protective film 27 protective film 29 first electrode 31 second electrode 33 third electrode 35 fourth electrode 37, 39 conductor pattern L1 first inductance element L1a conductor pattern L2a conductor pattern L2 second inductance element L2a conductor pattern L2b Conductor pattern L3 Third inductance element L3a Conductor pattern L3b Conductor pattern L3c Conductor pattern L4 Fourth inductance element L5 Fifth inductance element Lg Length CP1 First current path CP2 Second current path Cr1 First coil Cr2 Second coil C1 Capacity C2 capacity Ir current

Claims (11)

A container with an RFID module,
an insulating base material forming the outer shape of the container;
a metal film formed on the first main surface of the substrate;
a slot formed on the substrate within the region where the metal film is formed;
The RFID module includes an RFIC element, a filter circuit that transmits a current due to electromagnetic waves having a unique resonance frequency that is a communication frequency to the RFIC element, and first and second electrodes connected to the filter circuit,
The first electrode and the metal film of the RFID module are electrically connected,
the second electrode of the RFID module and the metal film are electrically connected with the RFID module straddling the slot ;
The container with the RFID module is a prefabricated box,
a side surface of the box having a recess extending longitudinally of the side surface, the slot being formed in the recess;
Container with RFID module. When the metal film is irradiated with an electromagnetic wave having a communication frequency, a current flows in a direction circulating the slot.
A container provided with the RFID module according to claim 1 . the length of the slot has a physical length of one-half wavelength of an electromagnetic wave at a communication frequency;
A container provided with the RFID module according to claim 1 . A container with an RFID module,
an insulating base material forming the outer shape of the container;
a metal film formed on the first main surface of the substrate;
a slot formed on the substrate within the region where the metal film is formed;
The RFID module includes an RFIC element, a filter circuit that transmits a current due to electromagnetic waves having a unique resonance frequency that is a communication frequency to the RFIC element, and first and second electrodes connected to the filter circuit,
The first electrode and the metal film of the RFID module are electrically connected,
the second electrode of the RFID module and the metal film are electrically connected with the RFID module straddling the slot;
The container with the RFID module is a prefabricated box,
said slot formed in a corner between a first side and a second side of said box;
Vessel with R FID module. A container with an RFID module,
an insulating base material forming the outer shape of the container;
a metal film formed on the first main surface of the substrate;
a slot formed on the substrate within the region where the metal film is formed;
The RFID module includes an RFIC element, a filter circuit that transmits a current due to electromagnetic waves having a unique resonance frequency that is a communication frequency to the RFIC element, and first and second electrodes connected to the filter circuit,
The first electrode and the metal film of the RFID module are electrically connected,
the second electrode of the RFID module and the metal film are electrically connected with the RFID module straddling the slot;
the slot is formed in a tapered portion formed between a first side and a second side of the box;
Vessel with R FID module. The metal film is formed on the entire first main surface of the base material except for the slots,
A container provided with the RFID module according to any one of claims 1 to 5 . wherein the filter circuit is an LC parallel resonant circuit,
A container provided with an RFID module according to any one of claims 1 to 6 . The filter circuit has a coil formed on a substrate,
the coil is covered with a protective layer;
A container provided with the RFID module according to claim 7 . the coil of the filter circuit has a figure eight shape;
A container provided with the RFID module according to claim 8 . The sheet resistance of the metal film is 0.5Ω/□ or more.
A container provided with an RFID module according to any one of claims 1-9 . The thickness of the metal film is 1 nm or more and 1 μm or less.
A container provided with the RFID module according to claim 10 .

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