Antenna device and IC card

Abstract

To provide an antenna device that can be made thin while suppressing contact between mesh-like conductor patterns, and an IC card.SOLUTION: An opening 20 has a through-hole 60 penetrating from one end 16a to the other end 16b in a thickness direction of a resin layer 16. Accordingly, the opening 20 can absorb a protruding shape of an IC module 50 by the through-hole 60. On the other hand, a slit 21 extends from the opening 20 to an edge 14c of a conductive pattern 14. A width of the slit 21 is smaller than that of the opening 20. The resin layer 16 is disposed in the slit 21. Therefore, the resin layer 16 can support the narrow slit 21. As a result, it is possible to prevent the conductor pattern 14 from coming into contact with each other near the slit 21.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present disclosure relates to an antenna device and an IC card. [Background technology]

[0002] Conventionally, an antenna device including a mesh-shaped conductor pattern is known (for example, see Patent Document 1). In this antenna device, a notch is formed in a location where an IC chip is to be disposed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-7655 Summary of the Invention [Problem to be solved by the invention]

[0004] In the antenna device described above, the cutouts are penetrations that penetrate the sheet. In this case, deformation of the cutouts can cause mesh patterns to come into contact with each other, forming loops and causing the antenna to no longer function. There is also a need to make the antenna device thinner.

[0005] Therefore, an object of the present disclosure is to provide an antenna device and an IC card that can be made thinner while suppressing contact between mesh-shaped conductor patterns. [Means for solving the problem]

[0006] An antenna device according to one aspect of the present disclosure comprises: a resin layer having a first trench extending in a first direction and a second direction intersecting the first direction; and a conductor pattern disposed in the first trench of the resin layer, the conductor pattern including a plurality of first conductive wires extending in the first direction and a plurality of second conductive wires extending in the second direction, and having a plurality of first mesh portions, wherein the conductor pattern includes a first region in which the first mesh portions are not formed, and a second region, the second region extending from the first region to an edge of the conductor pattern, the width of the second region being smaller than the width of the first region, the first region having a through hole penetrating from one end to the other end in the thickness direction of the resin layer, and the resin layer is disposed in the second region.

[0007] An IC card according to one aspect of the present disclosure comprises a card body including a first card substrate and a second card substrate, the above-mentioned antenna device disposed between the first card substrate and the second card substrate, and an IC module disposed within an IC mounting opening provided in the first card substrate. [Effects of the Invention]

[0008] According to one aspect of the present disclosure, it is possible to provide an antenna device and an IC card that can be made thinner while suppressing contact between mesh-shaped conductor patterns. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic perspective view showing the appearance of an IC card incorporating an antenna device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is an exploded perspective view of the IC card as seen from the bottom side. [Figure 3] FIG. 2 is a cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 2 is a plan view of the antenna device. [Figure 5] FIG. 2 is a cross-sectional view of the antenna device. [Figure 6] FIG. 10 is a developed cross-sectional view showing an IC card according to a modified example. [Figure 7]FIG. 10 is a developed cross-sectional view showing an IC card according to a modified example. [Figure 8] FIG. 10 is a developed cross-sectional view showing an IC card according to a modified example. [Figure 9] FIG. 10 is a cross-sectional view showing an IC card according to a modified example. [Figure 10] FIG. 10 is a diagram for explaining dimensions of a conductive wire. [Figure 11] FIG. 10 is an enlarged view of the vicinity of the connection between the slit and the opening. [Figure 12] FIG. 10 is an enlarged view of the vicinity of the connection between the slit and the opening. [Figure 13] FIG. 2 is an enlarged view of the vicinity of the outer peripheral surface of the protective layer. [Figure 14] FIG. 2 is a plan view of the antenna device. [Figure 15] 11. (a) is a cross-sectional view taken along line XVa-XVa shown in FIG. 11, and (b) is a cross-sectional view taken along line XVb-XVb shown in FIG. [Figure 16] FIG. 10 is a plan view of an antenna device according to a modified example. [Figure 17] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, several embodiments of the present disclosure will be described in detail, but the present disclosure is not limited to the following embodiments.

[0011] FIG. 1 is a schematic perspective view showing the appearance of an IC card 100 incorporating an antenna device according to an embodiment of the present disclosure. The IC card 100 shown in FIG. 1 is a plate-like body with its short side oriented in the y-axis direction, its long side oriented in the x-axis direction, and its thickness oriented in the z-axis direction, and has an upper surface a and a lower surface b that form an xy plane. The IC card 100 incorporates an IC module 50 (described later) and an antenna device, and a terminal electrode E of the IC module is exposed on the upper surface a of the IC card 100. When the IC card 100 is brought close to a card reader 110, communication via the antenna device can be performed. Applications of the IC card 100 are not particularly limited, and it may be applied to a transparent IC card capable of contactless communication in which the conductive wires and conductor patterns that constitute the antenna are not visible, such as a transparent dual-interface card such as a bank card or credit card.

[0012] FIG. 2 is an exploded perspective view of the IC card 100 as viewed from the bottom surface b. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 1. FIG. 3 shows the structure around the IC module 50. As shown in FIGS. 2 and 3, the IC card 100 includes a card body 80, an antenna device 1, and an IC module 50. The card body 80 has a first card substrate 2 and a second card substrate 3. The IC card 100 has a structure in which the first card substrate 2, the antenna device 1, and the second card substrate 3 are stacked in this order from the top surface a to the bottom surface b. The IC card 100 also includes the IC module 50. In this embodiment, the IC module 50 is located in a region of the IC card 100 on the negative side in the X-axis direction, closer to the positive side in the Y-axis direction. However, the position of the IC module 50 is not particularly limited. In the example shown in FIG. 3, the conductive lines of the conductor pattern 14 of the antenna device 1 are exposed from the inner circumferential surface of the through-hole and the outer circumferential surface of the resin layer 16 (details will be described later).

[0013] The first card substrate 2 is a plate-like member covering the main surface 1a on the positive side in the z-axis direction of the antenna device 1. A printed layer 40 provided on the surface on the positive side in the z-axis direction of the first card substrate 2 constitutes the top surface a of the IC card 100. The first card substrate 2 is provided with a substantially rectangular IC mounting opening 4. The IC mounting opening 4 penetrates the first card substrate 2 in the thickness direction (Z-axis direction). An IC module 50 is disposed inside the IC mounting opening 4 (see FIG. 3 ). The second card substrate 3 is a plate-like member covering the main surface 1b on the negative side in the z-axis direction of the antenna device 1. A printed layer 41 provided on the surface on the negative side in the z-axis direction of the second card substrate 3 constitutes the bottom surface b of the IC card 100. The first card substrate 2 is bonded to the antenna device 1 via an adhesive layer 11. The second card substrate 3 is bonded to the antenna device 1 via an adhesive layer 12.

[0014] The card substrates 2 and 3 may be transparent resin substrates. The card substrates 2 and 3 may be made of, for example, cellulose propionate (CP), polyvinyl chloride (PVD), polycarbonate (PC), tempered glass, etc. The thickness of the card substrates 2 and 3 is not particularly limited, but may be 100 to 500 μm. The total light transmittance of the card substrates 2 and 3 may be 90 to 100%. In the embodiment shown in FIG. 3, the first card substrate 2 is formed to be thicker than the second card substrate 3.

[0015] The adhesive layers 11 and 12 may be made of a highly transparent thermoplastic resin or thermosetting resin adhesive sheet. The adhesive sheet may be made of an acrylic, urethane, epoxy, or phenolic material. The adhesive layers 11 and 12 may be substrate-free, have high total light transmittance, and low haze. The thickness of the adhesive layers 11 and 12 is not particularly limited, but may be 10 to 100 μm. The total light transmittance of the adhesive layers 11 and 12 may be 90 to 100%.

[0016] Fig. 4 is a plan view of the antenna device 1. As shown in Fig. 4, the antenna device 1 is a rectangular plate-shaped member. The antenna device 1 has an edge 1c on the negative side in the x-axis direction, an edge 1d on the positive side in the x-axis direction, an edge 1e on the negative side in the y-axis direction, and an edge 1f on the positive side in the y-axis direction. In this embodiment, the edges 1c and 1d are short sides, and the edges 1e and 1f are long sides.

[0017] The antenna device 1 includes a mesh-shaped conductor pattern 14 having a plurality of first mesh portions 17 (see FIG. 5), and a resin layer 16 that supports the conductor pattern 14. The conductor pattern 14 is a mesh-shaped pattern including a plurality of regularly arranged first mesh portions 17 (see FIG. 5) formed by a plurality of conductive lines that intersect with each other. The pattern configuration of the conductor pattern 14 will be described in detail later. The conductor pattern 14 is formed on substantially the entire main surface 1a of the antenna device 1. The conductor pattern 14 has a rectangular shape that corresponds to the shape of the main surface 1a. The conductor pattern 14 has an edge 14c on the negative side in the x-axis direction, an edge 14d on the positive side in the x-axis direction, an edge 14e on the negative side in the y-axis direction, and an edge 14f on the positive side in the y-axis direction.

[0018] The conductor pattern 14 has an opening 20 (first region) and a slit 21 (second region) extending from the opening 20 to an edge 14c of the conductor pattern 14, which are regions where the first mesh portion 17 and conductive lines (first conductive lines and second conductive lines described below) are not formed. The opening 20 is configured as a through-hole that penetrates the antenna device 1 from the main surface 1a to the main surface 1b. The opening 20 is formed at a position where the IC module 50 is to be disposed. The opening 20 has a rectangular shape corresponding to the shape of the IC module 50. The slit 21 extends from the opening 20 to the edge 14c. The slit 21 extends from the side of the opening 20 on the negative side in the x-axis direction to the edge 14c on the negative side in the x-axis direction of the conductor pattern 14. The slit 21 extends parallel to the x-axis direction with a constant width. The width of the slit 21 and the width of the opening 20 are dimensions in a direction perpendicular to the extending direction of the slit 21 and the penetrating direction of the opening 20, i.e., the distance between edges extending along the extending direction of the slit 21. The width of the slit 21 (dimension in the y-axis direction) is smaller than the width of the opening 20 (dimension in the y-axis direction).

[0019] As shown in FIG. 5(a), the antenna device 1 includes a substrate 13, a conductor pattern 14 provided on one first principal surface 13a of the substrate 13, and a resin layer 16 provided on the first principal surface 13a of the substrate 13. The resin layer 16 has a first trench 44 extending in a direction along the first principal surface 13a of the substrate 13. The first trench 44 is a groove structure formed in the resin layer 16, and here extends from one end 16a to the other end 16b in the thickness direction of the resin layer 16. The conductor pattern 14 extends in a direction along the first principal surface 13a of the substrate 13 and has a plurality of first mesh portions 17. Each conductive line of the conductor pattern 14 is disposed within the first trench 44 of the resin layer 16. The conductor pattern 14 has conductor portions 18 that form the first mesh portion 17. The resin layer 16 is disposed between the plurality of conductor portions 18, i.e., within the first mesh portion 17. As a result, the plurality of conductors 18 are supported by the resin layer 16. In Fig. 5, the conductors 18 are shown in a deformed state, with the width and pitch of the conductors 18 adjusted.

[0020] The base material 13 has a degree of light transmittance required for the antenna device 1. The antenna device 1 in which the conductor pattern 14 having a plurality of first mesh portions 17 and the resin layer 16 are provided on the base material 13 may have a total light transmittance of 80% or more, and specifically, the total light transmittance of the base material 13 may be 90 to 100%. The haze of the base material 13 may be 0 to 5%.

[0021] The substrate 13 may be, for example, a transparent resin film, examples of which include polyethylene terephthalate (PET), polycarbonate (PC), polyethylene naphthalate (PEN), cycloolefin polymer (COP), or polyimide (PI) films. Alternatively, the substrate 13 may be a glass substrate.

[0022] The thickness of the substrate 13 may be 10 μm or more, 20 μm or more, or 35 μm or more, and may be 500 μm or less, 200 μm or less, or 100 μm or less.

[0023] The conductor portion 18 may contain a metal. The conductor portion 18 may contain at least one metal selected from copper, nickel, cobalt, palladium, silver, gold, platinum, and tin, or may contain copper. The conductor portion 18 may be a metal plating formed by a plating method. The conductor portion 18 may be a metal layer formed by printing and applying a metal paste. The conductor portion 18 may further contain a non-metallic element such as phosphorus, as long as appropriate conductivity is maintained.

[0024] The resin layer 16 is made of a light-transmitting resin and is provided so as to fill the first mesh portion 17, and usually the resin layer 16 and the conductor portion 18 form a flat surface.

[0025] The resin layer 16 is made of a resin having optical transparency. The resin layer 16 may have a total light transmittance of 90 to 100%. The resin layer 16 may have a haze of 0 to 5%.

[0026] The resin forming the resin layer 16 may be a cured product of a curable resin composition (a photocurable resin composition or a thermosetting resin composition). The curable resin composition forming the resin layer 16 includes a curable resin, examples of which include acrylic resin, amino resin, cyanate resin, isocyanate resin, polyimide resin, epoxy resin, oxetane resin, polyester, allyl resin, phenol resin, benzoxazine resin, xylene resin, ketone resin, furan resin, COPNA resin, silicone resin, dicyclopentadiene resin, benzocyclobutene resin, episulfide resin, ene-thiol resin, polyazomethine resin, polyvinylbenzyl ether compound, acenaphthylene, and ultraviolet-curable resins containing functional groups that undergo a polymerization reaction under ultraviolet light, such as unsaturated double bonds, cyclic ethers, and vinyl ethers.

[0027] As shown in Fig. 3, in the opening 20, a through-hole is formed that penetrates the resin layer 16 and the base material 13 in the z-axis direction. Therefore, the opening 20 is an area where the resin layer 16, the base material 13, and the conductor pattern 14 are not present. In the antenna device 1 in a state before being assembled into the IC card 100, a space SP is provided in the opening 20 (see Fig. 2). In the antenna device 1 in a state after being assembled into the IC card 100, a module including an IC chip 52 is placed in the space SP of the opening 20. Note that within the space SP, the periphery of the IC chip 52 is covered with a protective resin 55.

[0028] The conductive pattern 14 and the resin layer 16 are disposed on the second card substrate 3 via the adhesive layer 12. In the example shown in Fig. 3, the conductive pattern 14 and the resin layer 16 are disposed on the substrate 13. In the IC card 100, the substrate 13 is disposed on the negative side in the z-axis direction, and the conductive pattern 14 and the resin layer 16 are disposed on the positive side in the z-axis direction. Therefore, the second card substrate 3, the substrate 13, the conductive pattern 14, and the first card substrate 2 are stacked in this order from the negative side to the positive side in the z-axis direction.

[0029] The IC module 50 includes a module substrate 51 and an IC chip 52 mounted on or built into the module substrate 51, and a coupling coil 53 is formed on the negative surface in the z-axis direction of the module substrate 51 (see also FIG. 2). A terminal electrode E shown in FIG. 1 is provided on the front surface of the module substrate 51.

[0030] The IC module 50 is disposed within the IC mounting opening 4 of the first card substrate 2. The inner peripheral surface of the IC mounting opening 4 is disposed so as to surround the IC module 50 from the outer peripheral side. The IC module 50 is disposed so as to face the opening 20 of the antenna device 1 at a position on the positive side in the z-axis direction. The dimensions of the opening 20 in the y-axis and x-axis directions are smaller than those of the IC module 50. Furthermore, the dimensions of the opening 20 in the y-axis and x-axis directions are smaller than those of the outer peripheral edge of the coupling coil 53 and larger than those of the inner peripheral edge of the coupling coil 53. Therefore, when viewed from the z-axis direction, the four inner peripheral surfaces 20e of the opening 20 are disposed so as to overlap with the four sides of the coupling coil 53. The first card substrate 2 has a larger opening than the antenna device 1 and the like. The coupling coil 53 is bonded to a stepped portion of the antenna device 1 via hot melt tape 46 and an adhesive layer 11.

[0031] The IC card 100 is not limited to the structure shown in FIG. 3, and may have structures shown in FIGS. 6 to 9. FIGS. 6 to 8 show developments in which each component is developed in the stacking direction (Z-axis direction). In the IC card 100 shown in FIG. 6, the conductor pattern 14 is disposed on the second card substrate 3 side (negative side in the Z-axis direction), and the substrate 13 is disposed on the first card substrate 2 side (positive side in the Z-axis direction). The IC mounting opening 4 of the first card substrate 2 has a step portion 4a that faces the coupling coil 53 on the negative side in the Z-axis direction. The coupling coil 53 is bonded to the step portion 4a via hot melt tape 46. The conductor pattern 14 is not exposed from the inner and outer peripheral surfaces of the resin layer 16, but is spaced apart from the inner and outer peripheral surfaces (the specific configuration will be described later).

[0032] In the IC card 100 shown in FIG. 7 , the base material 13 of the antenna device 1 is omitted. As a result, in the antenna device 1, the resin layer 16 and the conductor pattern 14 exist as individual sheets without being supported by the base material 13, as shown in FIG. 5( b). In the configuration shown in FIG. 7 , the conductor pattern 14 and the resin layer 16 are formed directly on the second card substrate 3, so not only the base material 13 but also the adhesive layer 12 are omitted. Furthermore, the thickness of the second card substrate 3 may be increased by the amount of these layers omitted. In the IC card 100 shown in FIG. 8 , the second card substrate 3 is thicker than the configuration shown in FIG. 6 and includes a groove 47. The groove 47 is located at a position corresponding to the opening 20. The groove 47 can be used as a space to accommodate the IC chip 52 and the protective resin 55. In this case, the thickness of the second card substrate 3 may be approximately the same as that of the first card substrate 2.

[0033] The IC card 100 shown in FIG. 9 is the IC card 100 shown in FIG. 3 with an additional infrared-shielding layer 15. The infrared-shielding layer 15, which blocks infrared rays, is disposed between the first card substrate 2 and the second card substrate 3. The substrate 13 is accordingly thinner. The infrared-shielding layer 15 is disposed between the first card member 2 and the antenna device 1 via an adhesive layer 11. The infrared-shielding layer 15 may be formed from a sheet-like film or may be formed by printing and applying a paste. The infrared-shielding layer 15 may be formed from a material that does not transmit infrared rays. When the IC card 100 is used to detect the presence of a card by attenuation of light, a light transmission density of greater than 1.1 is required in the light wavelength range of 950 nm to 1000 nm. Therefore, the infrared-shielding layer 15 may be formed from a material that does not transmit infrared rays while satisfying this light transmission density. This light transmission density is specified by the international card standard (ISO / IEC 7810).

[0034] The antenna device 1 may also have a structure shown in FIG. 5(c). The antenna device 1 shown in FIG. 5(c) has a blackening layer 48 at the end of each conductive wire of the conductor portion 18. The blackening layer 48 is provided within the first trench 44. The blackening layer 48 is provided at the end 16a opposite the substrate 13 so as to cover the end of the conductive wire of the conductor portion 18 within the first trench 44. The blackening layer 48 can contribute to improving the visibility of the IC card 100 incorporating the antenna device 1. The blackening layer 48 may be formed by subjecting the conductor portion 18 to a blackening treatment, or a Ni layer (plating) may be laminated thereon as an alternative to the blackening treatment. Alternatively, the conductor portion 18 may be sandwiched between Ni layers, such as Ni layer / conductor portion / Ni layer, so that the blackening layers 48 are present both above and below.

[0035] Next, the function of the antenna device 1 will be described with reference to FIG. 4. A current CA flows in the coupling coil 53 (see FIG. 2) of the IC module 50. In FIG. 4, the current CA flows counterclockwise. At this time, magnetic flux B (see FIG. 2) of the coupling coil 53 acts on the edge of the opening 20. As a result, a clockwise eddy current CB flows in the conductor pattern 14 near the edge of the opening 20. In this way, the conductor pattern 14 near the edge of the opening 20 functions as a coupling coil that is magnetically coupled to the coupling coil 53 of the IC module 50. Here, the conductor pattern 14 at the edge on the negative side in the x-axis direction of the opening 20 is divided by the slit 21 up to the edge 14c. Therefore, the eddy current CB is divided by the slit 21, and currents CCa and CCb flow in the x-axis direction along the slit 21. A current CCa flows in the conductor pattern 14 at the edge on the negative side in the y-axis direction of the slit 21, from the opening 20 toward the edge 14c. As a result, a counterclockwise current CD flows through the entire conductor pattern 14. A current CCb flows through the conductor pattern 14 at the edge of the slit 21 on the positive side in the y-axis direction, returning from the edge 14c side to the opening 20. As described above, a current flows through the entire conductor pattern 14 of the antenna device 1 in the same direction as the IC module 50, allowing the antenna device 1 to function as an antenna.

[0036] Next, the conductor pattern 14 will be described in detail with reference to FIG. 11. FIG. 11 is an enlarged view of the vicinity of the connection between the slit 21 and the opening 20. FIG. 11 shows an edge 21a on the negative side in the y-axis direction of the slit 21 and an edge 21b on the positive side in the y-axis direction. Also shown are an edge 20a on the negative side in the y-axis direction, an edge 20b on the positive side in the y-axis direction, and an edge 20c on the negative side in the x-axis direction of the opening 20. The edges 20a, 20b, 21a, and 21b extend parallel to the x-axis direction. The edge 20c extends parallel to the y-axis direction.

[0037] As shown in FIG. 11 , the conductor pattern 14 includes a plurality of first conductive wires 30 and a plurality of second conductive wires 31. The first conductive wires 30 are linear conductor portions 18 that extend parallel to the x-axis direction (first direction). The plurality of first conductive wires 30 are arranged to be spaced apart from one another in the y-axis direction. The plurality of first conductive wires 30 are arranged to be spaced apart at an equal pitch. The second conductive wires 31 are linear conductor portions 18 that extend parallel to the y-axis direction (second direction). The plurality of second conductive wires 31 are arranged to be spaced apart from one another in the x-axis direction. The plurality of second conductive wires 31 are arranged to be spaced apart at an equal pitch.

[0038] While the dimensions of the conductive wires 30 and 31 are not particularly limited, it is preferable that the mesh sheet alone, consisting of the resin layer 16 and the conductor pattern 14, can achieve the desired characteristics. For example, by adjusting the dimensions of the conductive wires 30 and 31, it is possible to reduce the sheet resistance while maintaining the desired aperture ratio, thereby achieving the desired antenna characteristics. As shown in FIG. 10, the line width W of the conductive wires 30 and 31 is not particularly limited, but may be set to, for example, 1 to 3 μm. The pitch P of the conductive wires 30 and 31 is also not particularly limited, but may be set to, for example, 25 to 100 μm. The first conductive wire 30 and the second conductive wire 31 have a line thickness greater than their line width. The line thickness T of the conductive wires 30 and 31 is the dimension in the z-axis direction. Therefore, the cross-sectional shape of the conductive wires 30 and 31 has a shape extending in the z-axis direction (see FIG. 3). The line thickness T of the conductive wires 30 and 31 is not particularly limited, but may be set to, for example, 2 to 6 μm. The ends of the conductive wires 30, 31 in the z-axis direction may or may not coincide with the surface of the resin layer 16 in the z-axis direction. The aspect ratio of the conductive wires 30, 31 may be set to, for example, 1 to 3. The aspect ratio of the conductive wires 30, 31 is the ratio between the wire thickness and the wire width.

[0039] In this embodiment, the first conductive wire 30 is substantially parallel to the x-axis direction, which is the extension direction of the slit 21. The other, second conductive wire 31, is substantially perpendicular to the x-axis direction, which is the extension direction. Note that the first conductive wire 30 does not have to be parallel to the x-axis direction as long as it extends in the x-axis direction, and the second conductive wire 31 does not have to be parallel to the y-axis direction as long as it extends in the y-axis direction.

[0040] The normal first mesh portion 17 other than the vicinity of the slits 21 and the vicinity of the openings 20 will be described. Each first mesh portion 17 is composed of a pair of adjacent first conductive wires 30 and a pair of adjacent second conductive wires 31. In this embodiment, each first mesh portion 17 has a square shape. However, if the pitch of the first conductive wires 30 and the pitch of the second conductive wires 31 are different from each other, the first mesh portion 17 will have a rectangular shape. A resin layer 16 (FIG. 5) is disposed in the internal space of the first mesh portion 17 surrounded by the four conductive wires 30, 31. The pitch of the first mesh portion 17 in the y-axis direction is equal to the pitch of the first conductive wires 30. The pitch of the first mesh portion 17 in the x-axis direction is equal to the pitch of the second conductive wires 31. In the first mesh portion 17, the first conductive wires 30 and the second conductive wires 31 only need to intersect, and do not necessarily have to be perpendicular to each other. In other words, a first mesh portion 17 may be employed in which the first conductive wires 30 and the second conductive wires 31 intersect at an angle.

[0041] Second conductive wires 31 are provided at the positions of the edges 21a and 21b of the slit 21. The first conductive wires 30 are interrupted at the positions of the second conductive wires 31 that make up the edges 21a and 21b. As a result, no first conductive wires 30 and no other second conductive wires 31 are present between the second conductive wires 31 that make up the edges 21a and 21b. The width of the slit 21 may be equal to or less than the pitch of the first mesh portion 17. Therefore, the edges 21a and 21b are provided between the second conductive wires 31 that are one pitch apart. However, the width of the slit 21 may be greater than the pitch of the first mesh portion 17 (see, for example, FIG. 4). The second conductive wires 31 do not have to be provided at the positions of the edges 21a and 21b, or they may be provided on only one of the edges 21a and 21b.

[0042] A resin layer 16 is disposed in the slit 21. Such a resin layer 16 may be referred to as a slit-filling resin layer 16A. The slit-filling resin layer 16A extends together with the slit 21 from the edge 20c of the opening 20 to the edge 14c of the conductive pattern 14 (see FIG. 4) between the second conductive lines 31, 31 that form the edges 21a, 21b. FIG. 15(a) is a cross-sectional view taken along line XVa-XVa in FIG. 11. As shown in FIG. 15(a), the slit-filling resin layer 16A, like the other portions of the resin layer 16, extends from one end 16a to the other end 16b in the thickness direction (z-axis direction).

[0043] 15(b) is a cross-sectional view taken along line XVb-XVb in FIG. 11. As shown in FIG. 15(b), the opening 20 has a through-hole 60 that penetrates from one end 16a to the other end 16b in the thickness direction (z-axis direction) of the resin layer 16. No resin layer 16 is disposed within this through-hole 60. Therefore, as shown in FIG. 3, the protruding shape of the IC module 50 can be disposed therein. As shown in FIG. 11, the edges 20a, 20b, and 20c of the opening 20 are defined by the inner peripheral surface 60a of the through-hole 60.

[0044] The conductive wires 30, 31 extending toward the opening 20 are interrupted at the position of the opening 20. Therefore, the conductive wires 30, 31 (i.e., the first mesh portion 17) are not formed at the opening 20. For example, when the configurations of FIGS. 3 and 9 described above are employed, the tip end of at least one of the conductive wires 30, 31 extending toward the opening 20 reaches the inner circumferential surface 60a of the through hole 60. Specifically, the tip end 31a of the second conductive wire 31 extending from the negative side toward the positive side in the y-axis direction toward the opening 20 reaches the edge portion 20a. The tip end 31a of the second conductive wire 31 extending from the positive side toward the negative side in the y-axis direction toward the opening 20 reaches the edge portion 20b. The tip end 30a of the first conductive wire 30 extending from the negative side toward the positive side in the x-axis direction toward the opening 20 reaches the edge portion 20c. As a result, the conductive wires 30 and 31 are exposed from the resin layer 16 at the inner circumferential surface 60a.

[0045] 6 to 8, the configuration shown in FIG. 12 may be employed. In FIG. 12, the tip of at least one of the conductive wires 30, 31 extending toward the opening 20 is spaced from the inner circumferential surface 60a of the through hole 60. Specifically, the tip 31a of the second conductive wire 31 extending from the negative side toward the positive side in the y-axis direction toward the opening 20 is spaced from the edge 20a toward the negative side in the y-axis direction. The tip 31a of the second conductive wire 31 extending from the positive side toward the negative side in the y-axis direction toward the opening 20 is spaced from the edge 20b toward the positive side in the y-axis direction. The tip 30a of the first conductive wire 30 extending from the negative side toward the positive side in the x-axis direction toward the opening 20 is spaced from the edge 20c toward the negative side in the x-axis direction. As a result, the inner peripheral surface 60a is a surface that is formed only by the resin layer 16, with the conductive wires 30 and 31 not exposed.

[0046] Next, with reference to FIG. 4, the configuration near the edge of the conductor pattern 14 will be described in more detail. For example, when the configurations of FIGS. 3 and 9 are employed, the edge portions 14c, 14d, 14e, and 14f of the conductor pattern 14 extend so as to coincide with the edge portions 1c, 1d, 1e, and 1f of the antenna device 1. Therefore, the tips of the conductor wires 30 and 31 that reach the edge portions 14c, 14d, 14e, and 14f of the conductor pattern 14 are exposed from the outer peripheral surface of the resin layer 16. Specifically, as shown in FIG. 13, the conductor wire 30 extending from the positive side to the negative side in the X-axis direction reaches the edge portion 1c of the antenna device 1 (the outer peripheral surface 16c of the resin layer 16). As a result, the tip portion 30b of the conductor wire 30 is exposed from the outer peripheral surface 16c of the resin layer 16. Note that the tips of the conductor wires 30 and 31 are also similarly exposed at the other outer peripheral surfaces 16c of the resin layer 16.

[0047] Alternatively, when the configurations shown in FIGS. 6 to 8 are employed, the configuration shown in FIG. 14 may be employed. In FIG. 14, the edges 14c, 14d, 14e, and 14f of the conductor pattern 14 extend parallel to and along the edges 1c, 1d, 1e, and 1f of the antenna device 1 and are disposed inward from the edges 1c, 1d, 1e, and 1f. Therefore, the resin layer 16 has an outer circumferential region 62 that extends outward from the tips 30b and 31b of the conductive wires 30 and 31 that reach the edges 14c, 14d, 14e, and 14f of the conductor pattern 14. The outer circumferential region 62 is formed on each of the four sides along the four edges 1c, 1d, 1e, and 1f of the antenna device 1. In the example shown in FIG. 4, no conductive wires are provided in the outer circumferential region 62, and the resin layer 16 extends in the outer circumferential region 62.

[0048] The configuration shown in FIG. 16 may also be employed. As shown in FIG. 16, the peripheral region 62 may have a peripheral conductor pattern 64 having a plurality of second mesh portions 63. The peripheral conductor pattern 64 is arranged with gaps 66 between it and the conductor pattern 14. Such peripheral conductor patterns 64 and gaps 66 are provided in the peripheral region 62 on all four sides. FIG. 17 is a cross-sectional view of the vicinity of the gaps 66. As shown in FIG. 11, the resin layer 16 has mesh-shaped second trenches 67 in the peripheral region 62. The resin layer 16 has a peripheral conductor pattern 64 having a plurality of second mesh portions 63 arranged in the second trenches 67.

[0049] As shown in FIG. 16 , the peripheral conductor pattern 64 has slits 68, from the inner edge 64a to the outer edge 64b, where the second mesh portion 63 is not formed. A virtual area VE is set by virtually extending the slits 21 of the conductor pattern 14 toward the peripheral area 62. In this case, the slits 68 of the peripheral conductor pattern 64 are provided at a position overlapping with the virtual area VE. Therefore, the slits 21 and 68 are configured as a single slit extending from the opening 20. The width of the slit 68 may be the same as the width of the slit 21. A resin layer 16 is also disposed in the slit 68. However, the position of the slit 68 is not particularly limited, and the slit 68 may be formed at a position that does not overlap with the virtual area VE of the slit 21.

[0050] The edges 14c, 14d, 14e, and 14f may be arranged without gaps from the edges 1c, 1d, 1e, and 1f, respectively, in which case the outer peripheral region 62 is not provided.

[0051] Next, the functions and effects of the antenna device 1 and the IC card 100 according to this embodiment will be described.

[0052] In the antenna device 1 according to this embodiment, the resin layer 16 has a first trench 44 extending in the X-axis direction (first direction) and the Y-axis direction (second direction). The conductor pattern 14 is disposed in the first trench 44 of the resin layer 16, includes conductive lines 30 and 31, and has a plurality of first mesh portions 17. Therefore, the conductor pattern 14 is sufficiently supported within the first trench 44 of the resin layer 16. The conductor pattern 14 includes an opening 20 (first region) where the first mesh portion 17 is not formed, and a slit 21 (second region). The opening 20 has a through hole 60 that penetrates the resin layer 16 from one end 16a to the other end 16b in the thickness direction. This allows the opening 20 to absorb the protruding shape of the IC module 50 (the protruding shape due to the protective resin 55) at the through hole 60. Meanwhile, the slit 21 extends from the opening 20 to an edge 14c of the conductor pattern 14. Furthermore, the width of the slit 21 is smaller than the width of the opening 20. Therefore, when the slit 21 is a through portion, the conductive patterns 14 separated by the slit 21 come into contact with each other near the slit 21, forming a loop and causing the antenna to malfunction. In contrast, in this embodiment, a resin layer 16 is disposed in the slit 21. Therefore, the resin layer 16 can support the narrow slit 21. This makes it possible to prevent the conductive patterns 14 from coming into contact with each other near the slit 21. As a result, it is possible to achieve a thinner design while preventing the mesh-shaped conductive patterns from coming into contact with each other.

[0053] At least one of the tip ends 30a, 30b of the first conductive wire 30 and the second conductive wire 31 extending toward the opening 20 may be spaced apart from the inner circumferential surface 60a of the through hole 60. In this case, the conductive wires 30, 31 are not exposed to the inner circumferential surface 60a of the through hole 60. This makes it possible to suppress deterioration of the conductive pattern 14.

[0054] The width of the slits 21 may be equal to or less than the pitch of the first mesh portion 17. In this case, by making the width of the slits 21, which are regions where the first mesh portion 17 is not formed, as small as possible, the invisibility of the conductor pattern 14 is improved.

[0055] The resin layer 16 may have a peripheral region 62 that extends outward from the first conductive wire 30 that reaches the edge of the conductive pattern 14 and the tip ends 30b, 31b of the second conductive wire 31. In this case, the peripheral region 62 can ensure insulation from the conductive pattern 14.

[0056] The resin layer 16 has a mesh-shaped second trench 67 in the peripheral region 62, and a peripheral conductor pattern 64 having a plurality of second mesh portions 63 arranged in the second trench 67, and the peripheral conductor pattern 64 may be arranged with a gap 66 between it and the conductor pattern 14. In this case, the peripheral conductor pattern 64 functions as a dummy mesh for the edge portion on the peripheral side of the conductor pattern 14, thereby improving the invisibility of the conductor pattern 14.

[0057] The peripheral conductor pattern 64 may have slits 68 extending from the inner edge 64a to the outer edge 64b where the second mesh portion 63 is not formed. In this case, the slits 68 prevent the peripheral conductor pattern 64, which is a dummy mesh, from forming a loop, thereby suppressing deterioration of characteristics due to a demagnetizing field that accompanies the formation of a loop.

[0058] The slits 68 of the peripheral conductor pattern 64 may overlap with a virtual area VE obtained by extending the slits 21 of the conductor pattern 14 toward the peripheral area 62. In this case, by concentrating the formation locations of the slits 21 and 68, the invisibility of the conductor patterns 14 and 64 can be improved.

[0059] The tip of at least one of the first conductive wire 30 and the second conductive wire 31 extending toward the opening 20 may be exposed from the inner peripheral surface 20e of the through hole. In this case, the tip of the conductive wires 30, 31 can be formed by, for example, punching.

[0060] The tip portions of the first conductive wire 30 and the second conductive wire 31 that reach the edge portions 14c, 14d, 14e, and 14f of the conductive pattern 14 may be exposed from the outer peripheral surface 16c of the resin layer 16. In this case, the tip portions of the conductive wires 30 and 31 can be formed by, for example, punching.

[0061] The IC card 100 of this embodiment comprises a card body 80 including a first card substrate 2 and a second card substrate 3, the above-mentioned antenna device 1 arranged between the first card substrate 2 and the second card substrate 3, and an IC module 50 arranged in an IC mounting opening 4 provided in the first card substrate 2.

[0062] According to this IC card 100, it is possible to obtain the same functions and effects as the antenna device 1 described above.

[0063] The conductive pattern 14 and the resin layer 16 may be disposed on the second card substrate 3. In this case, after the cards are stacked, damage caused by mechanical cutting during the outline cutting process and cavity processing (processing of a hole to fill the IC module 50) of the IC card 100 can be mitigated by the second card substrate 3. Therefore, the mesh-like conductive pattern 14 can be protected.

[0064] The conductive pattern 14 and the resin layer 16 may be disposed on the substrate 13, and the second card substrate 3, the conductive pattern 14, the substrate 13, and the first card substrate 2 may be laminated in this order. In this case, the substrate can ensure insulation between the conductive pattern 14 and the IC module 50.

[0065] An infrared shielding layer 15 that blocks infrared rays may be disposed between the first card substrate 2 and the second card substrate 3. In this case, the presence of the IC card 100 can be detected in applications that detect the presence of a card by attenuation of light between a light source and a sensor.

[0066] The present disclosure is not limited to the above-described embodiments.

[0067] For example, the positions and arrangements of the components of the IC card 100 and the antenna device 1 described above are merely examples and can be changed as appropriate without departing from the spirit of the present invention, and some components may be omitted.

[0068] For example, a resin layer 16 may be formed on the front and back of the substrate 13, a first conductive wire 30 may be placed in a first trench 44 in the resin layer 16 on the front side, and a second conductive wire 31 may be placed in a first trench 44 in the resin layer 16 on the back side, forming a mesh shape on the front and back sides.

[0069] [Form 1] a resin layer having a first trench extending in a first direction and a second direction intersecting the first direction; a conductor pattern disposed in the first trench of the resin layer, the conductor pattern including a plurality of first conductive lines extending in the first direction and a plurality of second conductive lines extending in the second direction, and the conductor pattern having a plurality of first mesh portions; the conductor pattern includes a first region in which the first mesh portion is not formed and a second region; the second region extends from the first region to an edge of the conductor pattern; the width of the second region is smaller than the width of the first region; the first region has a through-hole penetrating from one end to the other end in a thickness direction of the resin layer, The antenna device, wherein the resin layer is disposed in the second region. [Form 2] The antenna device of claim 1, wherein the tip of at least one of the first conductive wire and the second conductive wire extending toward the first region is spaced apart from the inner surface of the through hole. [Form 3] 3. The antenna device according to claim 1, wherein the width of the second region is equal to or less than the pitch of the first mesh portion. [Form 4] The antenna device according to any one of the first to third embodiments, wherein the resin layer has an outer peripheral region extending outward from the tip of the first conductive wire and the second conductive wire to the edge of the conductive pattern. [Form 5] the resin layer has a mesh-shaped second trench in the outer periphery region, and a peripheral conductor pattern having a plurality of second mesh portions arranged in the second trench; 5. The antenna device according to claim 4, wherein the outer circumferential conductor pattern is disposed with a gap between it and the conductor pattern. [Form 6] The antenna device according to embodiment 5, wherein the outer circumferential conductor pattern has a slit from an inner edge to an outer edge where the second mesh portion is not formed. [Form 7] 7. The antenna device according to claim 6, wherein the slit of the peripheral conductor pattern overlaps with a virtual area formed by extending the second area of the conductor pattern toward the peripheral area. [Form 8] The antenna device according to any one of the first to seventh embodiments, wherein a tip end of at least one of the first conductive wire and the second conductive wire extending toward the first region is exposed from an inner circumferential surface of the through hole. [Form 9] The antenna device according to embodiment 1, wherein the tip portions of the first conductive wire and the second conductive wire that reach the edge of the conductor pattern are exposed from the outer peripheral surface of the resin layer. [Form 10] a card body including a first card substrate and a second card substrate; the antenna device according to any one of aspects 1 to 9, which is disposed between the first card substrate and the second card substrate; an IC module placed in an IC mounting opening of the first card substrate. [Form 11] 11. The IC card according to claim 10, wherein the conductive pattern and the resin layer are disposed on the second card substrate. [Form 12] the conductor pattern and the resin layer are disposed on a substrate, 12. The IC card according to claim 11, wherein the second card substrate, the conductive pattern, the substrate, and the first card substrate are laminated in this order. [Form 13] 13. The IC card according to any one of modes 10 to 12, wherein an infrared shielding layer for blocking infrared rays is disposed between the first card substrate and the second card substrate. [Explanation of symbols]

[0070] 1...antenna device, 2...first card substrate, 3...second card substrate, 4...opening for mounting IC, 13...substrate, 14...conductor pattern, 15...infrared shielding layer, 16...resin layer, 17...first mesh portion, 20...opening (first region), 21...slit (second region), 30...first conductive wire, 31...second conductive wire, 44...first trench, 50...IC module, 62...outer peripheral region, 63...second mesh portion, 67...second trench, 80...card body, 100...IC card.

Claims

1. a resin layer having a first trench extending in a first direction and a second direction intersecting the first direction; a conductor pattern disposed in the first trench of the resin layer, the conductor pattern including a plurality of first conductive lines extending in the first direction and a plurality of second conductive lines extending in the second direction, and the conductor pattern having a plurality of first mesh portions; the conductor pattern includes a first region in which the first mesh portion is not formed and a second region; the second region extends from the first region to an edge of the conductor pattern; the width of the second region is smaller than the width of the first region; the first region has a through-hole penetrating from one end to the other end in a thickness direction of the resin layer, The antenna device, wherein the resin layer is disposed in the second region.

2. The antenna device according to claim 1 , wherein a tip end of at least one of the first conductive wire and the second conductive wire extending toward the first region is spaced apart from an inner circumferential surface of the through hole.

3. The antenna device according to claim 1 , wherein the width of the second region is equal to or less than the pitch of the first mesh portion.

4. The antenna device according to claim 1 , wherein the resin layer has an outer circumferential region extending outward from the tip ends of the first conductive wires and the second conductive wires that reach the edges of the conductor pattern.

5. the resin layer has a mesh-shaped second trench in the outer periphery region, and a peripheral conductor pattern having a plurality of second mesh portions arranged in the second trench; The antenna device according to claim 4 , wherein the peripheral conductor pattern is disposed with a gap from the conductor pattern.

6. The antenna device according to claim 5 , wherein the outer circumferential conductor pattern has a slit extending from an inner edge to an outer edge, in which the second mesh portion is not formed.

7. The antenna device according to claim 6 , wherein the slit in the peripheral conductor pattern overlaps with an imaginary area obtained by extending the second area of the conductor pattern toward the peripheral area.

8. The antenna device according to claim 1 , wherein a tip end of at least one of the first conductive wire and the second conductive wire extending toward the first region is exposed from an inner circumferential surface of the through hole.

9. The antenna device according to claim 1 , wherein tip portions of the first conductive wire and the second conductive wire that reach an edge of the conductor pattern are exposed from an outer peripheral surface of the resin layer.

10. a card body including a first card substrate and a second card substrate; The antenna device according to any one of claims 1 to 9, which is disposed between the first card substrate and the second card substrate; an IC module disposed in an IC mounting opening of the first card substrate.

11. The IC card according to claim 10 , wherein the conductor pattern and the resin layer are disposed on the second card substrate.

12. the conductor pattern and the resin layer are disposed on a substrate, The IC card according to claim 11 , wherein the second card substrate, the conductor pattern, the substrate, and the first card substrate are laminated in this order.

13. The IC card according to claim 10 , wherein an infrared shielding layer that blocks infrared rays is disposed between the first card substrate and the second card substrate.

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