Coil component and IC card equipped with the same

Abstract

To reduce the overall thickness while ensuring the reliability of a coil pattern in a coil component including the coil pattern and a magnetic body covering the coil pattern.SOLUTION: A coil component 1 includes a magnetic body 30, a first coil pattern CP1 arranged on one surface side of the magnetic body 30, and a first resin layer 10 arranged on one surface side of the magnetic body 30 and containing particles and a binder resin R1. The first coil pattern CP has a first surface S1 facing the magnetic body 30 and a second surface S2 located on the opposite side of the first surface S1. The first coil pattern CP1 is embedded in the first resin layer 10, with at least the first surface S1 and the second surface S2 not exposed from the first resin layer 10.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a coil component and an IC card including the same. [Background technology]

[0002] Patent Document 1 discloses a coil module including a coil substrate on which a coil pattern is formed, an adhesive layer that covers the coil substrate so as to embed the coil pattern, and a magnetic layer that is adhered to the adhesive layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-005113 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the coil module described in Patent Document 1 has a problem in that the entire thickness is increased due to the presence of the coil substrate.

[0005] The present disclosure describes a technique for reducing the overall thickness of a coil component including a coil pattern and a magnetic body covering the coil pattern while ensuring the reliability of the coil pattern. [Means for solving the problem]

[0006] A coil component according to one embodiment of the present disclosure comprises a magnetic body, a first coil pattern arranged on one surface side of the magnetic body, and a first resin layer arranged on one surface side of the magnetic body and containing particles and a binder resin, wherein the first coil pattern has a first surface facing the magnetic body and a second surface located opposite the first surface, and the first coil pattern is embedded in the first resin layer, and at least the first surface and the second surface are covered by the first resin layer. [Effects of the Invention]

[0007] According to the present disclosure, a technique is provided for reducing the overall thickness of a coil component including a coil pattern and a magnetic body covering the coil pattern while ensuring the reliability of the coil pattern. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic perspective view showing the appearance of an IC card 2 including a coil component according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic exploded perspective view illustrating the structure of an IC card 2 equipped with the coil device 1. As shown in FIG. [Figure 3] FIG. 3 is a schematic cross-sectional view illustrating the structure of an IC card 2 equipped with the coil device 1. As shown in FIG. [Figure 4] FIG. 4 is a schematic plan view illustrating the configuration of the coil device 1. As shown in FIG. [Figure 5] FIG. 5 is a schematic perspective view of the IC module 60 as seen from the rear side. [Figure 6] FIG. 6 is a schematic diagram showing a state in which the IC card 2 and the card reader 6 communicate with each other. [Figure 7] FIG. 7 is a schematic cross-sectional view taken along line BB shown in FIG. [Figure 8] FIG. 8 is a schematic cross-sectional view taken along line CC shown in FIG. [Figure 9] FIG. 9 is a schematic cross-sectional view for explaining the first modified example, showing a cross section taken along line CC shown in FIG. [Figure 10] FIG. 10 is a schematic cross-sectional view for explaining the second modified example, showing a cross section taken along line CC shown in FIG. [Figure 11] FIG. 11 is a schematic cross-sectional view for explaining the third modified example, showing a cross section taken along line CC shown in FIG. [Figure 12] FIG. 12 is a schematic cross-sectional view for explaining the fourth modified example, showing a cross section taken along line CC shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Preferred embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings.

[0010] FIG. 1 is a schematic perspective view showing the appearance of an IC card 2 including a coil component according to an embodiment of the present disclosure.

[0011] 1, the IC card 2 according to this embodiment is a plate-like body with the Y direction as the longitudinal direction, the X direction as the lateral direction, and the Z direction as the thickness direction, and has an upper surface 2a and a back surface 2b that form the XY plane. The IC card 2 has an IC module (described later) built in, and terminal electrodes E of the IC module are exposed on the upper surface 2a of the IC card 2.

[0012] 2 and 3 are a schematic exploded perspective view and a schematic cross-sectional view, respectively, for explaining the structure of an IC card 2 including the coil device 1 according to this embodiment.

[0013] 2 and 3 has a structure in which a plastic plate 40, a coil component 1, and a metal plate 50 are laminated in this order from the back surface 2b side toward the top surface 2a side. The coil component 1 according to this embodiment is composed of a magnetic body 30, and a coil pattern CP and a first resin layer 10 arranged on one surface side (+Z direction) of the magnetic body 30. The other surface side (-Z direction) of the magnetic body 30 is covered with the metal plate 50.

[0014] The magnetic body 30 and the metal plate 50 have through holes 31 and 51, respectively. These through holes 31 and 51 overlap in the Z direction, which is the stacking direction. The plastic plate 40 and the coil component 1 are bonded via an adhesive layer 71. The metal plate 50 and the coil component 1 are bonded via an adhesive layer 72. Examples of materials for the adhesive layers 71 and 72 include acrylic double-sided tape, thermosetting resin, and thermoplastic resin.

[0015] The plastic plate 40 is made of a resin material that does not interfere with magnetic flux. The outer surface of the plastic plate 40 forms the back surface 2b of the IC card 2. The metal plate 50 is made of a metal material such as stainless steel or titanium. The outer surface of the metal plate 50 forms the top surface 2a of the IC card 2. A through hole 51 is provided in the metal plate 50, and an IC module 60 is disposed inside the through hole 51. In this way, the IC card 2 is a card in which a metal plate is used for the main body.

[0016] The IC module 60 includes a module substrate 61, an IC chip 62 mounted on or built into the module substrate 61, and a coupling coil 63. The IC chip 62 is protected by being covered with a dome-shaped protective resin 64. A terminal electrode E shown in FIG. 1 is provided on the surface of the module substrate 61 opposite to the surface on which the IC chip 62 is mounted. The IC module 60 having such a configuration is electromagnetically coupled to a second coil pattern CP2 that is part of the coil pattern CP. This enables communication between an external card reader and the IC chip 62 via a first coil pattern CP1 that is another part of the coil pattern CP. In other words, the first coil pattern CP1 is an antenna coil, and the second coil pattern CP2 is a coupling coil.

[0017] 4 is a schematic plan view illustrating the configuration of the coil component 1 according to this embodiment. Line AA shown in FIG. 4 indicates the cross-sectional position of FIG.

[0018] 4, the coil pattern CP included in the coil component 1 according to this embodiment includes a first coil pattern CP1 that makes multiple turns around the outer edge of the magnetic body 30 so as to overlap the magnetic body 30, and a second coil pattern CP2 that is connected to each turn of the first coil pattern CP1 and makes multiple turns around so as to overlap the through-hole 31 of the magnetic body 30. The first coil pattern CP1 and the second coil pattern CP2 are located on the same plane. The second coil pattern CP2 overlaps in the Z direction with the IC module 60 placed in the through-hole 51 of the metal plate 50, via the through-hole 31 of the magnetic body 30.

[0019] 4, the first coil pattern CP1 and the second coil pattern CP2 each have approximately four turns. The second coil pattern CP2 is a portion that winds around the first coil pattern CP1 so as to protrude toward the opening CP1a. In other words, each turn of the coil pattern CP is composed of the first coil pattern CP1 having less than one turn and the second coil pattern CP2 having less than one turn.

[0020] The first coil pattern CP1 functions as an antenna coil that couples with an external card reader during actual use. The second coil pattern CP2 functions as a coupling coil that couples with the IC module 60. The second coil pattern CP2 may function as part of an antenna coil that couples with an external card reader. The pattern width W11 of the first coil pattern CP1 may be larger than the pattern width W12 of the second coil pattern CP2. This reduces the DC resistance of the first coil pattern CP1 and ensures a sufficient opening size for the second coil pattern CP2. Here, if the pattern width of the first coil pattern CP1 is not uniform, the pattern width W11 may be defined by the maximum pattern width, minimum pattern width, or average pattern width of the first coil pattern CP1. Similarly, if the pattern width of the second coil pattern CP2 is not uniform, the pattern width W12 may be defined by the maximum pattern width, minimum pattern width, or average pattern width of the second coil pattern CP2.

[0021] Furthermore, when the outer peripheral edge 101 of the coil pattern CP is the starting point and the inner peripheral edge 102 of the coil pattern CP is the end point, the first coil pattern CP1 winds counterclockwise and the second coil pattern CP2 winds clockwise when viewed from the direction shown in Fig. 4. In other words, the winding directions of the first coil pattern CP1 and the second coil pattern CP2 are opposite to each other.

[0022] FIG. 5 is a schematic perspective view of the IC module 60 as seen from the rear side.

[0023] As shown in FIG. 5, the IC module 60 includes a module substrate 61, an IC chip 62 mounted on or built into the module substrate 61, and a coupling coil 63. The IC chip 62 is protected by being covered with a dome-shaped protective resin 64. The protective resin 64 is made of an insulating material. The terminal electrodes E shown in FIG. 1 are provided on the front surface of the module substrate 61. The IC module 60 having such a configuration is housed in a through hole 51 formed in a metal plate 50. When the IC module 60 is housed in the through hole 51, the coupling coil 63 and the second coil pattern CP2 are electromagnetically coupled. The second coil pattern CP2 is connected to the first coil pattern CP1, which functions as an antenna coil, and the IC module 60 can communicate with the outside via the first coil pattern CP1.

[0024] 6, when the back surface 2b of the IC card 2 faces the card reader 6, communication can be performed between the card reader 6 and the IC chip 62. In other words, the card reader 6 is coupled to the coupling coil 63 of the IC module 60 via the coil pattern CP, thereby realizing communication with the IC chip 62.

[0025] Fig. 7 is a schematic cross-sectional view taken along line BB shown in Fig. 4. Fig. 8 is a schematic cross-sectional view taken along line CC shown in Fig. 4.

[0026] 7 and 8, the first coil pattern CP1 and the second coil pattern CP2 are embedded in a first resin layer 10. The first resin layer 10 has a structure in which a first layer 11 and a second layer 12 are stacked in the Z direction, but if the first layer 11 and the second layer 12 are made of the same material, the interface 13 between them is not necessarily clear.

[0027] The first coil pattern CP1 and the second coil pattern CP2 each include a seed portion S containing resin, and a main body portion M made of a metal material laminated on the seed portion S. The metal material making up the main body portion M may be Cu. The seed portion S may contain a material that functions as a catalyst when plating the main body portion M. The conductivity of the main body portion M may be higher than the conductivity of the seed portion S. Furthermore, the thickness of the main body portion M may be thicker than the thickness of the seed portion S. These features make it possible to reduce the resistance values ​​of the first coil pattern CP1 and the second coil pattern CP2.

[0028] The seed portion S forms the first surface S1 of the first coil pattern CP1 and the fifth surface S5 of the second coil pattern CP2, and the main body portion M forms the second surface S2 of the first coil pattern CP1 and the sixth surface S6 of the second coil pattern CP2. In this embodiment, the entire surfaces of the first coil pattern CP1 including the first surface S1 and the second surface S2 and the second coil pattern CP2 including the fifth surface S5 and the sixth surface S6 are covered with the first resin layer 10 without being exposed.

[0029] The first coil pattern CP1 and the second coil pattern CP2 may be formed on the surface of a substrate (not shown), the first coil pattern CP1 and the second coil pattern CP2 are embedded in a first layer 11, and then the substrate is peeled off and a second layer 12 is formed.

[0030] The thickness T11, which is the distance in the Z direction between the surface 10A of the first resin layer 10 and the first surface S1 of the first coil pattern CP1 and the fifth surface S5 of the second coil pattern CP2, may be thinner than the thickness T12, which is the distance in the Z direction between the surface 10B of the first resin layer 10 and the first surface S1 of the first coil pattern CP1 and the fifth surface S5 of the second coil pattern CP2. The surface 10B of the first resin layer 10 constitutes a third surface facing the magnetic body 30. The surface 10A of the first resin layer 10 constitutes a fourth surface located opposite the surface 10B. When the thickness T11 is thinner than the thickness T12, the thickness T12 necessarily becomes larger than the distance T13 between the surface 10A of the first resin layer 10 and the second surface S2 of the first coil pattern CP1 and the sixth surface S6 of the second coil pattern CP2. This allows the first coil pattern CP1 to be offset in the -Z direction from the center in the Z direction of the first resin layer 10, thereby reducing the influence of the metal plate 50 on the first coil pattern CP1. Note that the thickness of the first layer 11 in the Z direction may be thinner than the thickness of the second layer 12 in the Z direction.

[0031] The main body portions M of the first coil pattern CP1 and the second coil pattern CP2 may have a shape in which their widths in the XY plane, i.e., the radial direction, narrow toward the +Z direction. The radial direction is the direction from the inner periphery of the coil pattern to the outer periphery. In this case, the first surface S1 of the first coil pattern CP1 and the fifth surface S5 of the second coil pattern CP2 are wider in the XY plane, i.e., the radial direction, than the second surface S2 of the first coil pattern CP1 and the sixth surface S6 of the second coil pattern CP2. By forming the first coil pattern CP1 and the second coil pattern CP2 in this shape, even if the first coil pattern CP1 and the second coil pattern CP2 are offset in the −Z direction from the center of the first resin layer 10 in the Z direction, the volume of the first resin layer 10 near the surface 10A is ensured, thereby improving the flatness of the surface 10A.

[0032] The first resin layer 10 may contain particles and a binder resin R1. The particles contained in the first resin layer 10 may be inorganic filler particles or black color pigment particles. When inorganic filler particles are used as the particles contained in the first resin layer 10, insulating inorganic filler particles F11 to F13 having different particle sizes may be used. The inorganic filler particles F11 to F13 have an average particle size of, for example, 0.4 to 13 μm. When black color pigment particles are used as the particles contained in the first resin layer 10, carbon black having an average particle size of, for example, 3 to 500 nm may be used.

[0033] In the example shown in FIG. 7, inorganic filler particles F11 to F13 are all spherical but have different particle sizes. Inorganic filler particles F11 are small-diameter fillers having a first particle size distribution with a first average particle size. Inorganic filler particles F12 are medium-diameter fillers having a second particle size distribution with a second average particle size larger than the first particle size. Inorganic filler particles F13 are large-diameter fillers having a third particle size distribution with a third average particle size larger than the second particle size. In this way, by using three types of inorganic filler particles F11 to F13 with different particle size distributions, the filling rate of the inorganic filler particles in the first resin layer 10 can be increased.

[0034] The inorganic filler particles F11 to F13 may be made of non-magnetic inorganic materials such as alumina, aluminum hydroxide, talc, magnesium hydroxide, silica, calcium carbonate, barium titanate, zirconium titanate, or zinc zirconate. Alternatively, magnetic materials such as ferrite or Fe-based alloy magnetic materials may be used. Examples of Fe-based alloy magnetic materials include permalloy, sendust, Fe-Si-Cr, Fe-Si, carbonyl iron, amorphous Fe-based alloy powder containing at least Fe-Si-B, or nanocrystalline Fe-based alloy powder containing at least Fe-BP-Cu. Using a magnetic material for the inorganic filler particles F11 to F13 increases the inductance of the first coil pattern CP1 and the second coil pattern CP2. The inorganic filler particles F11 to F13 may be made of the same material or may be made of partially different materials. The dielectric constant of the inorganic filler particles F11 to F13 may be higher than that of the binder resin R1.

[0035] Examples of materials for binder resin R1 include acrylic resin, polyester resin, polyethylene resin, polyvinyl chloride resin, polyvinyl butyral resin, polyurethane resin, polyester urethane resin, cellulose resin, ABS (acrylonitrile-butadiene-styrene) resin, nitrile-butadiene rubber, styrene-butadiene rubber, epoxy resin, phenolic resin, amide resin, polyester elastomer, polyamide elastomer, etc. The elongation percentage determined by a tensile test of the resin used as binder resin R1 may be greater than 400%.

[0036] The density of the inorganic filler particles F11 to F13 in the first resin layer 10 may be locally high in a position that is flush with the area between the first surface S1 and the second surface S2 of the first coil pattern CP1 (a position that is flush with the area between the fifth surface S5 and the sixth surface S6 of the second coil pattern CP2), that is, in the region indicated by the symbol D. This increases the capacitance generated between adjacent turns of the first coil pattern CP1 and the second coil pattern CP2.

[0037] The magnetic body 30 is used to prevent application of magnetic flux to the metal plate 50 by covering the first coil pattern CP1, which is an antenna coil. The magnetic body 30 is not disposed in a position overlapping with the second coil pattern CP2, which is a coupling coil, i.e., a position overlapping with the through-hole 51 of the metal plate 50, but the through-hole 31 is provided instead. The thickness T30 of the magnetic body 30 in the Z direction is, for example, 50 μm. The thickness T30 of the magnetic body 30 may be thicker than the thickness T10 of the first resin layer 10. This increases the inductance of the first coil pattern CP1.

[0038] The magnetic body 30 may be a magnetic resin layer containing flat magnetic powder F3 and binder resin R3. The flat magnetic powder F3 may be composed of a metal magnetic material such as sendust, permalloy, Fe-Si-Cr-based alloy magnetic material, Fe-Si-Al-Cr-based alloy magnetic material, or Fe-Al-Cr-based alloy magnetic material. The thickness direction of the flat magnetic powder F3 is the Z direction, and the longitudinal direction is the XY plane direction perpendicular to the Z direction. The flat magnetic powder F3 is oriented so that its longitudinal direction is approximately parallel to the XY plane direction. This increases the magnetic permeability of the magnetic body 30 in the XY plane direction. However, the longitudinal direction of all the flat magnetic powder F3 does not need to be strictly parallel to the XY plane direction; the longitudinal direction of some of the flat magnetic powder F3 may be inclined with respect to the XY plane direction. The size of the flat magnetic powder F3 in the XY plane direction may be larger than the thickness T30 in the Z direction of the magnetic body 30. This further increases the magnetic permeability of the magnetic body 30 in the XY plane direction.

[0039] Examples of materials for the binder resin R3 include acrylic resin, polyester resin, polyethylene resin, polyvinyl chloride resin, polyvinyl butyral resin, polyurethane resin, polyester urethane resin, cellulose resin, ABS (acrylonitrile-butadiene-styrene) resin, nitrile-butadiene rubber, styrene-butadiene rubber, epoxy resin, phenolic resin, amide resin, polyester elastomer, and polyamide elastomer. The binder resin R3 may be the same resin material as the binder resin R1 contained in the first resin layer 10, or may be a different resin material. The elongation percentage of the resin used as the binder resin R3 determined by a tensile test may be greater than 400%. When the binder resin R1 contained in the first resin layer 10 and the binder resin R3 contained in the magnetic material 30 are made of the same resin material, the adhesion between the first resin layer 10 and the magnetic material 30 is enhanced. A curing agent may be added to the binder resin R3. Adding a curing agent to the binder resin R3 improves the heat resistance and moisture resistance of the magnetic body 30. When the magnetic body 30 is a magnetic resin layer containing flat magnetic powder F3 and binder resin R3, the ratio of the flat magnetic powder F3 to the binder resin R3 (=F3 / R3) may be approximately 4 to 8. This makes it possible to increase the magnetic permeability of the magnetic body 30. On the other hand, for the first resin layer 10, the ratio of the filler particles F11 to F13 to the binder resin R1 (=(F11+F12+F13) / R1) may be smaller than the value of F3 / R3. This makes it possible to increase the adhesion of the first resin layer 10 to the coil pattern CP and the magnetic body 30.

[0040] As described above, in the coil component 1 according to this embodiment, the first coil pattern CP1 and the second coil pattern CP2 are embedded in the first resin layer 10 without being exposed, thereby improving the reliability of the first coil pattern CP1 and the second coil pattern CP2. Furthermore, even if voids are generated around the first coil pattern CP1 and the second coil pattern CP2, the voids are confined within the first resin layer 10, thereby further improving the reliability of the first coil pattern CP1 and the second coil pattern CP2. Moreover, since the first coil pattern CP1 is not exposed from the first resin layer 10, the flatness of the surfaces 10A and 10B of the first resin layer 10 is also improved. Furthermore, since the base material used to form the first coil pattern CP1 and the second coil pattern CP2 is peeled off, the overall thickness is also reduced.

[0041] FIG. 9 is a schematic cross-sectional view for explaining the first modified example, showing a cross section taken along line CC shown in FIG.

[0042] 9 differs from the structure shown in FIG. 8 in that the thickness of the first resin layer 10 is locally reduced at the position overlapping the through hole 31 of the magnetic body 30. In other words, the thickness T14 of the first resin layer 10 at the position overlapping the through hole 31 is thinner than the thickness T10 of the first resin layer 10 at the position overlapping the magnetic body 30. The other basic configuration is the same as the structure shown in FIG. 7, so the same elements are denoted by the same reference numerals and redundant explanations will be omitted.

[0043] The second coil pattern CP2 is embedded in the first resin layer 10 without being exposed from the first resin layer 10. This makes it possible to protect the second coil pattern CP2 and prevent interference between the IC module 60 and the first resin layer 10 even when the IC module 60 is thick.

[0044] FIG. 10 is a schematic cross-sectional view for explaining the second modified example, showing a cross section taken along line CC shown in FIG.

[0045] In the second modified example shown in Fig. 10, the thickness of the first resin layer 10 is further reduced at the position overlapping the through hole 31 of the magnetic body 30, so that part of the second coil pattern CP2 is exposed from the first resin layer, and another part of the second coil pattern CP2 is embedded in the first resin layer 10. As shown in Fig. 10, the second layer 12 constituting the first resin layer 10 is entirely removed at the position overlapping the through hole 31 of the magnetic body 30. As a result, the first layer 11 is present at the position overlapping the through hole 31, but the second layer 12 is not present. Since the other basic configuration is the same as the structure shown in Fig. 9, the same elements are assigned the same reference numerals and redundant explanations will be omitted.

[0046] This makes it possible to prevent interference between the IC module 60 and the first resin layer 10 and the second coil pattern CP2 even when the IC module 60 is thicker. Here, the first surface S1 of the second coil pattern CP2 that is exposed from the first resin layer 10 is made of the seed portion S that has lower conductivity than the main body portion M, so that exposure of the second coil pattern CP2 hardly reduces reliability.

[0047] FIG. 11 is a schematic cross-sectional view for explaining the third modified example, showing a cross section taken along line CC shown in FIG.

[0048] The third modified example shown in Fig. 11 differs from the structure shown in Fig. 7 in that the magnetic body 30 is made of a ferrite sintered body. Since the other basic configurations are the same as those shown in Fig. 7, the same elements are given the same reference numerals and redundant explanations will be omitted.

[0049] As illustrated in the third modified example shown in FIG. 11 , the magnetic body 30 may be a ferrite sintered body. This can further increase the inductance of the first coil pattern CP1. The ferrite sintered body may be an aggregate of pieces P divided into multiple pieces by cracks extending in the Z direction. This can prevent damage to the magnetic body 30 made of the ferrite sintered body. The extension direction of the cracks does not need to be strictly the Z direction; cracks inclined with respect to the Z direction or cracks extending in the XY plane direction may be included. Furthermore, the binder resin R1 constituting the first resin layer 10 may permeate the gaps (cracks) between the ferrite sintered body pieces P. This fixes the pieces P together with the binder resin R1, thereby increasing the strength of the magnetic body 30. Note that the binder resin R1 may permeate only some of the gaps between the ferrite sintered body pieces P, or only the regions of the gaps on the first resin layer 10 side.

[0050] FIG. 12 is a schematic cross-sectional view for explaining the fourth modified example, showing a cross section taken along line CC shown in FIG.

[0051] 12 differs from the structure shown in Fig. 7 in that it further includes a second resin layer 20 located on the opposite side of the magnetic body 30 from the first resin layer 10. Since the other basic configurations are the same as those in the structure shown in Fig. 7, the same elements are given the same reference numerals and redundant explanations will be omitted.

[0052] The second resin layer 20 may be made of the same material as the first resin layer 10. That is, the second resin layer 20 may contain spherical inorganic filler particles F2 that are the same as the filler particles F11 to F13 contained in the first resin layer 10, and a binder resin R2 that is the same as the binder resin R1 contained in the first resin layer 10. Since the second resin layer 20 does not need to embed the coil pattern CP, the ratio of filler particles to binder resin can be higher than that of the first resin layer 10, which increases the strength of the second resin layer 20.

[0053] In this way, by sandwiching the magnetic body 30 between the first resin layer 10 and the second resin layer 20, it is possible to protect the magnetic body 30 from both sides. In addition, the second resin layer 20 makes it possible to attach the magnetic body 30 to another member. For example, the second resin layer 20 can be used as an adhesive layer in place of the adhesive layer 72 in FIG. 3 .

[0054] The above describes preferred embodiments of the present disclosure, but the present disclosure is not limited to the above embodiments, and various modifications are possible within the scope of the present disclosure, and it goes without saying that these modifications are also included within the scope of the present disclosure.

[0055] For example, the second resin layer 20 shown in FIG. 12 may be added to the magnetic body 30 made of sintered ferrite shown in FIG.

[0056] The technology according to the present disclosure includes, but is not limited to, the following configuration examples.

[0057] A coil component according to an embodiment of the present disclosure includes a magnetic body, a first coil pattern disposed on one surface of the magnetic body, and a first resin layer disposed on the one surface of the magnetic body and containing particles and a binder resin, the first coil pattern having a first surface facing the magnetic body and a second surface located on the opposite side of the first surface, the first coil pattern being embedded in the first resin layer, and at least the first and second surfaces being covered by the first resin layer. This makes it possible to reduce the overall thickness while improving the reliability of the first coil pattern.

[0058] In the above coil component, the first resin layer has a third surface facing the magnetic body and a fourth surface located opposite the third surface, and the distance between the first surface of the first coil pattern and the third surface of the first resin layer may be greater than the distance between the second surface of the first coil pattern and the fourth surface of the first resin layer. This allows the distance between the first coil pattern and the metal member to be increased even when a metal member such as a metal plate is disposed on the surface of the magnetic body opposite the first resin layer.

[0059] In the coil component, the first surface of the first coil pattern may be wider in the radial direction than the second surface of the first coil pattern, thereby improving the flatness of the first resin layer.

[0060] In the above coil component, the first coil pattern may include a seed portion containing resin and a main portion made of a metal material and laminated on the seed portion, with the seed portion constituting the first surface and the main portion constituting the second surface. This improves the magnetic properties of the coil component even when a metal member such as a metal plate is disposed on the surface of the magnetic body opposite to the first resin layer.

[0061] The coil component further includes a second coil pattern connected to the first coil pattern and located on the same plane as the first coil pattern, and the magnetic body may have a through hole, and the second coil pattern may overlap the through hole. In this way, when an IC module or the like is placed in a position overlapping the through hole, the second coil pattern can function as a coupling coil.

[0062] In the coil component described above, the thickness of the first resin layer at the position overlapping the through hole may be thinner than the thickness of the first resin layer at the position overlapping the magnetic body. This makes it possible to prevent interference between the IC module and the coil component even when the IC module is thick. In this case, the second coil pattern may be embedded in the first resin layer, and a fifth surface of the second coil pattern facing the through hole and a sixth surface located opposite the fifth surface may be covered by the first resin layer. In this case, the second coil pattern is protected by the first resin layer. Alternatively, the second coil pattern may include a seed portion containing resin and a main portion made of a metal material and laminated on the seed portion. A portion of the second coil pattern including the seed portion may be exposed from the first resin layer, and another portion of the second coil pattern including the main portion may be embedded in the first resin layer. This makes it possible to prevent interference between the IC module and the coil component even when the IC module is thick.

[0063] In the coil component, the particles may include inorganic filler particles, and the density of the inorganic filler particles in the first resin layer may be locally high at a position that is flush with the first and second surfaces of the first coil pattern, thereby increasing the capacitance generated between adjacent turns of the first coil pattern.

[0064] The coil component may further include a second resin layer that covers the other surface of the magnetic body from the side opposite to the first resin layer, thereby making it possible to protect the magnetic body from both sides.

[0065] An IC card according to an embodiment of the present disclosure includes the above coil component, making it possible to provide a thin, highly reliable IC card. [Explanation of symbols]

[0066] 1 Coil parts 2. IC card 2a Top of IC card 2b Back of IC card 6. Card Reader 10 1st resin layer 10A, 10B Surface of first resin layer 11 1st layer 12 2nd layer 13 Interface 20 Second resin layer 30 Magnetic material 31 Through hole 40 plastic plates 50 Metal Plates 51 Through hole 60 IC modules 61 Module Board 62 IC chips 63 Coupling coil 64 Protective Resin 71,72 Adhesive layer 101 Outer edge 102 Inner periphery CP coil pattern CP1 First coil pattern CP1a First coil pattern opening CP2 Second coil pattern E terminal electrode F11~F13, F2 Inorganic filler particles F3 flat magnetic powder M Main body P piece R1~R3 ​​binder resin S Seed Section

Claims

1. A magnetic material, a first coil pattern disposed on one surface side of the magnetic body; a first resin layer disposed on the one surface side of the magnetic body and containing particles and a binder resin; the first coil pattern has a first surface facing the magnetic body and a second surface located on the opposite side of the first surface; the first coil pattern is embedded in the first resin layer, and at least the first surface and the second surface are covered with the first resin layer; Coil parts.

2. the first resin layer has a third surface facing the magnetic body and a fourth surface located on the opposite side of the third surface, a distance between the first surface of the first coil pattern and the third surface of the first resin layer is greater than a distance between the second surface of the first coil pattern and the fourth surface of the first resin layer; The coil component according to claim 1 .

3. The first surface of the first coil pattern has a wider radial width than the second surface of the first coil pattern. The coil component according to claim 2 .

4. the first coil pattern includes a seed portion including a resin, and a main body portion laminated on the seed portion and made of a metal material, the seed portion constitutes the first surface and the body portion constitutes the second surface. The coil component according to claim 3 .

5. a second coil pattern connected to the first coil pattern and located on the same plane as the first coil pattern; the magnetic body has a through hole, the second coil pattern overlaps with the through hole; The coil component according to claim 1 .

6. a thickness of the first resin layer at a position overlapping the through hole is thinner than a thickness of the first resin layer at a position overlapping the magnetic body; The coil component according to claim 5 .

7. the second coil pattern is embedded in the first resin layer, a fifth surface of the second coil pattern facing the through hole and a sixth surface of the second coil pattern positioned opposite to the fifth surface are covered with the first resin layer; The coil component according to claim 6 .

8. the second coil pattern includes a seed portion including a resin, and a main body portion made of a metal material and laminated on the seed portion, a portion of the second coil pattern including the seed portion is exposed from the first resin layer, and another portion of the second coil pattern including the main body portion is embedded in the first resin layer; The coil component according to claim 6 .

9. the particles include inorganic filler particles; the density of the inorganic filler particles in the first resin layer is locally high at a position that is flush with the first surface and the second surface of the first coil pattern; The coil component according to claim 1 .

10. a second resin layer covering the other surface side of the magnetic body from the side opposite to the first resin layer; The coil component according to claim 1 .

11. An IC card comprising the coil component according to any one of claims 1 to 10.

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