Coil component and IC card provided with same

Abstract

In a coil component including a coil pattern and a magnetic body covering the coil pattern, a gap around the coil pattern is suppressed. A coil component (1) is provided with: a coil pattern (CP) that includes a seed portion (S) that contains a resin and has first and second surfaces (S1, S2) on opposite sides from each other, and a body portion (M) that is laminated on the second surface (S2) of the seed portion (S) and is made of a metal material; a magnetic body (30) covering the coil pattern (CP); and a first resin layer (10) that is positioned between the coil pattern (CP) and the magnetic body (30) and contains spherical filler particles (F1) and a binder resin (R1). The coil pattern (CP) is embedded in the first resin layer (10) such that the first surface (S1) of the seed portion (S) is exposed from the first resin layer (10).

Description

Technical Field

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

[0002] Patent Document 1 discloses a structure in which wiring constituting a coil pattern is covered with a magnetic layer containing magnetic particles.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-161152 Summary of the Invention

[0006] Technical Problem to be Solved by the Invention

[0007] However, since the magnetic particles described in Patent Document 1 have a flat shape, if the aspect ratio is increased to improve magnetic properties, the magnetic layer cannot follow the unevenness on the insulating layer caused by the wiring. As a result, there is a problem that voids are generated around the wiring.

[0008] The present disclosure describes a technique for suppressing voids around a coil pattern in a coil component including a coil pattern and a magnetic body covering the coil pattern.

[0009] Means for Solving the Technical Problem

[0010] A coil component provided by an embodiment of the present disclosure includes: a coil pattern including a seed portion and a main body portion, the seed portion containing resin and having first and second surfaces located on opposite sides, the main body portion being laminated on the second surface of the seed portion and made of a metal material; a magnetic body covering the coil pattern; and a first resin layer located between the coil pattern and the magnetic body and containing spherical filler particles and an adhesive resin, the coil pattern being buried in the first resin layer such that the first surface of the seed portion is exposed from the first resin layer.

[0011] Advantageous Effects of the Invention

[0012] According to the present disclosure, a technique for suppressing voids around a coil pattern in a coil component including a coil pattern and a magnetic body covering the coil pattern can be provided. Brief Description of the Drawings

[0013] Figure 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.

[0014] Figure 2 is a schematic exploded perspective view for explaining the structure of an IC card 2 including a coil component 1.

[0015] Figure 3 It is a schematic cross-sectional view for explaining the structure of the IC card 2 having the coil component 1.

[0016] Figure 4 It is a partial cross-sectional view of the coil component 1.

[0017] Figure 5 It is a partial cross-sectional view of the coil component 1A of the first modification example.

[0018] Figure 6 It is a partial cross-sectional view of the coil component 1B of the second modification example.

[0019] Figure 7 It is a partial cross-sectional view of the coil component 1C of the third modification example.

[0020] Figure 8 It is a partial cross-sectional view of the coil component 1D of the fourth modification example.

[0021] Symbol Explanation

[0022] 1, 1A, 1B, 1C, 1D... Coil component

[0023] 2... IC card

[0024] 2a... Upper surface of the IC card

[0025] 2b... Back surface of the IC card

[0026] 10... First resin layer

[0027] 10A, 10B... Surfaces of the first resin layer

[0028] 20... Second resin layer

[0029] 30... Magnetic body

[0030] 40... Plastic plate

[0031] 50... Metal plate

[0032] 51... Through hole

[0033] 60... IC module

[0034] 61... Module substrate

[0035] 62... IC chip

[0036] 63... Coupling coil

[0037] 64... Protective resin

[0038] 71, 72... Adhesive layer

[0039] CP... Coil pattern

[0040] CP1... Coupling coil

[0041] CP2... Antenna coil

[0042] E... Terminal electrode

[0043] F1... Filler particles

[0044] F3... Flat magnetic powder

[0045] M... Main body part

[0046] P... Monolithic

[0047] R1, R3... Adhesive resin

[0048] S... Seed part

[0049] S1, S2... Surfaces of the seed part Detailed implementation manners

[0050] Next, preferred implementation manners of the present disclosure will be described in detail with reference to the accompanying drawings.

[0051] Figure 1 is a schematic perspective view showing the appearance of an IC card 2 having a coil component according to an implementation manner of the present disclosure.

[0052] As Figure 1 shown, the IC card 2 of the present implementation manner is a plate-like body with the Y direction as the long side direction, the X direction as the short side direction, and the Z direction as the thickness direction, and has an upper surface 2a and a back surface 2b that constitute the XY plane. An IC module described later is built in the IC card 2, and the terminal electrode E of the IC module is exposed on the upper surface 2a of the IC card 2.

[0053] Figure 2 and Figure 3 are respectively a schematic exploded perspective view and a schematic cross-sectional view for explaining the structure of the IC card 2 having the coil component 1 of the present implementation manner.

[0054] Figure 2 and Figure 3 shown, the IC card 2 has a structure in which a plastic plate 40, a coil component 1, and a metal plate 50 are laminated in sequence from the back surface 2b side to the upper surface 2a side. The coil component 1 of the present implementation manner is composed of a coil pattern CP, a first resin layer 10, and a magnetic body 30. 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 the materials for the adhesive layers 71 and 72 include acrylic double-sided tapes, thermosetting resins, and thermoplastic resins.

[0055] The plastic plate 40 is made of a resin material that does not obstruct magnetic flux. The outer surface of the plastic plate 40 constitutes 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 constitutes the upper surface 2a of the IC card 2. A through-hole 51 is provided in the metal plate 50, and the IC module 60 is disposed inside the through-hole 51. Thus, the IC card 2 is a card that uses a metal plate for the main body.

[0056] The IC module 60 includes a module substrate 61, an IC chip 62 mounted on or built in 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. Terminal electrodes E as shown are provided on the surface of the module substrate 61 on the side opposite to the surface on which the IC chip 62 is mounted. Figure 1 The IC module 60 having such a structure performs electromagnetic field coupling with a coupling coil CP1 that is part of a coil pattern CP. Thereby, communication can be performed between an external card reader and the IC chip 62 via an antenna coil CP2 that is another part of the coil pattern CP.

[0057] Figure 4 is a partial cross-sectional view of the coil component 1.

[0058] As Figure 4 shown, the coil pattern CP is embedded in the first resin layer 10 such that a first surface S1 of the seed portion S thereof is exposed from the surface 10A of the first resin layer 10. The coil pattern CP includes a seed portion S containing resin and a main body portion M made of a metal material and laminated on a second surface S2 of the seed portion S. The first surface S1 of the seed portion S is exposed from the first resin layer 10. The first surface S1 and the second surface S2 are located on opposite sides of each other. The coil pattern CP is formed on the surface of a substrate (not shown), but the substrate can also be peeled off later. In this case, the coil component 1 does not include the substrate. Thereby, the thickness of the coil component 1 in the Z direction is reduced. The Z direction is the coil axis direction of the coil pattern CP and is also the thickness direction of the coil pattern CP. Alternatively, the substrate can be directly retained without being peeled off. In this case, the first surface S1 of the seed portion S is constituted by the substrate used for forming the coil pattern CP.

[0059] The coil pattern CP is embedded in the first resin layer 10 such that the first surface S1 of the seed portion S is exposed from the surface 10A of the first resin layer 10. The metal material of the main body portion M constituting the coil pattern CP can also be Cu. The seed portion S can also contain a material that functions as a catalyst when the main body portion M is formed by plating. The thickness of the main body portion M can also be thicker than the thickness of the seed portion S. Thereby, the resistance value of the coil pattern CP can be reduced.

[0060] The main body M may not be exposed from the first resin layer 10 but may be entirely buried in the first resin layer 10. Alternatively, a part of the main body M, for example, the part covering the side surface of the seed portion S, may be exposed from the first resin layer 10. In Figure 4 the example shown, the seed portion S is also buried in the first resin layer 10, and the surface 10A of the first resin layer 10 and the first surface S1 of the seed portion S form the same plane.

[0061] The first resin layer 10 is located between them in such a manner as to be sandwiched by the coil pattern CP and the magnetic body 30 in the Z direction. The first resin layer 10 contains spherical filler particles F1 and a binder resin R1. The thickness T of the first resin layer 10 in the Z direction 10 is, for example, 30 to 50 μm. Since the surface 10B of the first resin layer 10 on the side in contact with the magnetic body 30 is substantially flat, the thickness of the first resin layer 10 becomes thinner at the portion where the coil pattern CP exists. The thickness T of the first resin layer between the coil pattern CP and the magnetic body 30 10’ is the value obtained by subtracting the thickness T 10 of the coil pattern CP from the thickness T CP of the first resin layer 10. The thickness T of the coil pattern CP CP is, for example, 10 to 30 μm.

[0062] The filler particles F1 are spherical. By using spherical filler particles F1, not only the strength of the first resin layer 10 is improved, but also voids are less likely to be generated around the coil pattern CP. As the material of the filler particles F1, non-magnetic inorganic materials such as alumina can be used, and magnetic materials such as ferrite and Fe-based alloy magnetic bodies can also be used. As the Fe-based alloy magnetic body, for example, permalloy, sendust, Fe-Si-Cr, Fe-Si, carbonyl iron, Fe-based alloy amorphous powder containing at least Fe-Si-B, or Fe-based alloy nanocrystalline powder containing at least Fe-B-P-Cu can be cited. If a magnetic material is used as the material of the filler particles F1, the inductance of the coil pattern CP is increased. The average particle diameter (D 50 ) of the filler particles F1 is, for example, 2 to 10 μm. In addition, the average particle diameter is the D 50 value in the laser diffraction particle size distribution measurement.

[0063] As materials for the adhesive resin R1, acrylic resins, polyester resins, polyethylene resins, polyvinyl chloride resins, polyvinyl butyral resins, polyurethane resins, polyester polyurethane resins, cellulose resins, ABS (acrylonitrile-butadiene-styrene) resins, nitrile-butadiene rubbers, styrene-butadiene rubbers, epoxy resins, phenolic resins, amide resins, polyester elastomers, polyamide elastomers, etc. can be cited. The elongation rate obtained by the tensile test of the resin used as the adhesive resin R1 can also be greater than 400%.

[0064] Here, the smaller the average particle diameter (D 50 ) of the filler particles F1, the thinner the thickness T of the first resin layer between the coil pattern CP and the magnetic body 30 10’ can be set. Accordingly, not only can the filling rate of the filler particles F1 in the first resin layer 10 be ensured, but also the filler particles F1 can be more uniformly dispersed. For example, when the average particle diameter (D 50 ) of the filler particles F1 is less than 5 μm, even if the thickness T of the first resin layer between the coil pattern CP and the magnetic body 30 10’ is set thinner than the thickness T CP of the coil pattern CP, not only can the filling rate of the filler particles F1 in the first resin layer 10 be ensured, but also the filler particles F1 can be uniformly dispersed. Therefore, the overall thickness of the coil component 1 can be made thinner, and the distance between the coil pattern CP and the magnetic body 30 can be shortened. On the other hand, when the average particle diameter (D 50 ) of the filler particles F1 is 5 μm or more, by setting the thickness T 10’ of the first resin layer between the coil pattern CP and the magnetic body 30 to be thicker than the thickness T CP of the coil pattern CP, not only can the filling rate of the filler particles F1 in the first resin layer 10 be ensured, but also the filler particles F1 can be uniformly dispersed.

[0065] The magnetic body 30 is used to prevent the application of magnetic flux to the metal plate 50 by covering the antenna coil CP2 which is a part of the coil pattern CP. The magnetic body 30 is not provided at the position overlapping with the coupling coil CP1, that is, at the position overlapping with the through hole 51 of the metal plate 50. The thickness T 30 in the Z direction of the magnetic body 30 is, for example, 50 μm. The thickness T 30 of the magnetic body 30 can also be thicker than the thickness T 10 of the first resin layer. Thereby, the inductance of the coil pattern CP is increased.

[0066] The magnetic body 30 may also be a magnetic resin layer containing flat magnetic powder F3 and binder resin R3. The flat magnetic powder F3 may also be composed of metal magnetic materials such as iron-silicon-aluminum alloy, permalloy, Fe-Si-Cr based alloy magnetic body, Fe-Si-Al-Cr based alloy magnetic body, or Fe-Al-Cr based alloy magnetic body. The thickness direction of the flat magnetic powder F3 is the Z direction, and the XY plane direction orthogonal to the Z direction is taken as the long side direction. The flat magnetic powder F3 is oriented such that the long side direction is substantially parallel to the XY plane direction. Thereby, the magnetic permeability in the XY plane direction of the magnetic body 30 can be increased. However, it is not necessary for the long side directions of all the flat magnetic powder F3 to be strictly parallel to the XY plane direction, and for the long side directions of a part of the flat magnetic powder F3, they may be inclined with respect to the XY plane direction. The size of the flat magnetic powder F3 in the XY plane direction may also be larger than the thickness T of the magnetic body 30 in the Z direction. 30 . Accordingly, the magnetic permeability in the XY plane direction of the magnetic body 30 is further increased.

[0067] Examples of the material of the binder resin R3 include acrylic resin, polyester resin, polyethylene resin, polyvinyl chloride resin, polyvinyl butyral resin, polyurethane resin, polyester polyurethane 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 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 rate obtained by the tensile test of the resin used as the binder resin R3 may also 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 body 30 are composed of the same resin material, the adhesion between the first resin layer 10 and the magnetic body 30 is improved. A curing agent may also be added to the binder resin R3. If a curing agent is added to the binder resin R3, the heat resistance and moisture resistance of the magnetic body 30 are improved. 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 about 4 to 8. Accordingly, the magnetic permeability of the magnetic body 30 can be increased. In contrast, for the first resin layer 10, the ratio of the filler particles F1 to the binder resin R1 (=F1 / R1) may also be smaller than the value of F3 / R3. Accordingly, the adhesion of the first resin layer 10 to the coil pattern CP and the magnetic body 30 can be improved.

[0068] Thus, in the coil component 1 of the present embodiment, since the first resin layer 10 is provided between the coil pattern CP and the magnetic body 30, even when the aspect ratio of the flat magnetic powder F3 contained in the magnetic body 30 is large, voids are not easily generated around the coil pattern CP. Therefore, peeling of the coil pattern CP and the like can be prevented. Moreover, since the spherical filler particles F1 are included in the first resin layer 10, generation of voids can be prevented and the strength of the first resin layer 10 can be increased.

[0069] In addition, compared with the case of using an adhesive sheet or the like instead of the first resin layer 10, the overall thickness of the coil component 1 can be reduced. In the present embodiment, since the base material for forming the coil pattern CP is removed, the overall thickness of the coil component 1 becomes thinner. In addition, since all or most of the main body portion M of the coil pattern CP does not expose from the surface 10A of the first resin layer 10 but the seed portion S is exposed, the main body portion M of the coil pattern CP can be protected.

[0070] Figure 5 FIG. is a partial cross-sectional view of the coil component 1A of the first modification.

[0071] Figure 5 In the coil component 1A of the first modification shown, the magnetic body 30 is composed of a ferrite sintered body, which is different from the coil component 1 shown in Figure 4 The other basic structures are the same as those of the coil component 1 shown in Figure 4 Therefore, the same reference numerals are assigned to the same elements and repeated descriptions are omitted.

[0072] As exemplified by the coil component 1A of the first modification, the magnetic body 30 may also be a ferrite sintered body. Accordingly, the inductance of the coil pattern CP can be further increased. The ferrite sintered body may also be an aggregate of single pieces P divided by cracks extending in the Z direction. Accordingly, breakage of the magnetic body 30 composed of the ferrite sintered body can be prevented. The extending direction of the cracks does not need to be strictly in the Z direction and may include cracks having an inclination with respect to the Z direction or cracks extending in the XY plane direction. In addition, the adhesive resin R1 constituting the first resin layer 10 may also penetrate into the gaps (cracks) between the single pieces P of the ferrite sintered body. Accordingly, since the single pieces P are fixed to each other by the adhesive resin R1, the strength of the magnetic body 30 can be increased. In addition, the penetration of the adhesive resin R1 into the gaps between the single pieces P of the ferrite sintered body may be only a part of the plurality of gaps or may be only the region on the first resin layer 10 side of the gaps.

[0073] Figure 6 FIG. is a partial cross-sectional view of the coil component 1B of the second modification.

[0074] Figure 6In the coil component 1B of the second modified example shown, the first resin layer 10 includes a first region 11 and a second region 12, and in this regard, it is different from Figure 4 the coil component 1 shown. The other basic structure is the same as that of Figure 4 the coil component 1 shown, so the same reference numerals are assigned to the same elements, and repeated descriptions are omitted.

[0075] The first region 11 is located on the side of the magnetic body 30. The second region 12 is a region in which the coil pattern CP is embedded and constitutes the surface 10A. A part of the coil pattern CP may also be embedded in the first region 11. The first region 11 and the second region 12 may be made of the same material or different materials. In this way, by forming the first resin layer 10 of two regions, the adhesion to the coil pattern CP and the magnetic body 30 can be improved. The first region 11 and the second region 12 may be formed by dividing the single-layer first resin layer 10 into two regions, or the first region 11 and the second region 12 may be formed by making the first resin layer 10 into a two-layer structure. The first resin layer 10 having a two-layer structure can be formed by coating the first layer (first region 11) on the surface of the magnetic body 30 and then coating the second layer (second region 12) on the surface of the first layer (first region 11).

[0076] Alternatively, the second layer (second region 12) may be coated on the surface of a substrate (not shown) for forming the coil pattern CP, and the first layer (first region 11) having the magnetic body 30 formed thereon may be laminated on the surface of the second layer (second region 12). In this case, if an uncured curing agent is added to the binder resin R3 contained in the magnetic body 30, the curing agent may sometimes penetrate into the first layer (first region 11) serving as the base. As a result, the characteristics of the first layer (first region 11) change, but since the curing agent does not reach the second layer (second region 12), the embedding characteristics of the coil pattern CP do not deteriorate. In addition, since the concentration of the curing agent contained in the first layer (first region 11) is lower than the concentration of the curing agent contained in the magnetic body 30 as the magnetic resin layer, the characteristics required for the first layer (first region 11) are not greatly damaged. Instead, the heat resistance and moisture resistance of the first resin layer 10 are improved, and the adhesion between the first resin layer 10 and the magnetic body 30 is improved.

[0077] Figure 7 is a partial cross-sectional view of the coil component 1C of the third modified example.

[0078] Figure 7 In the coil component 1C of the third modified example shown, a second resin layer 20 is further provided on the surface of the magnetic body 30 opposite to the first resin layer 10, and in this regard, it is different from Figure 6 the coil component 1B shown. The other basic structure is the same as that of Figure 6Since it is the same as the coil component 1B shown, the same symbols are assigned to the same elements, and redundant explanations are omitted.

[0079] The second resin layer 20 may also be made of the same material as the first resin layer 10. That is, the second resin layer 20 may also contain spherical filler particles the same as the filler particles F1 contained in the first resin layer 10 and a binder resin the same as the binder resin R1 contained in the first resin layer 10. For the second resin layer 20, since it is not necessary to embed the coil pattern CP, the ratio of the filler particles to the binder resin can be higher than that of the first resin layer 10, whereby the strength of the second resin layer 20 is increased.

[0080] Thus, if the magnetic body 30 is sandwiched between the first resin layer 10 and the second resin layer 20, the magnetic body 30 can be protected from both sides. In addition, the magnetic body 30 can be adhered to other members through the second resin layer 20. For example, the second resin layer 20 can be used as an adhesive layer instead of Figure 3 the adhesive layer 72 in

[0081] Figure 8 is a partial cross-sectional view of the coil component 1D of the fourth modified example.

[0082] Figure 8 In the coil component 1D of the fourth modified example shown, the thickness of the magnetic body 30 at the portion not overlapping with the coil pattern CP is larger than the thickness of the magnetic body 30 at the portion overlapping with the coil pattern CP, which is different from the coil component 1 shown in Figure 4 . The other basic structure is the same as that of the coil component 1 shown in Figure 4 Since it is the same as the coil component 1 shown, the same symbols are assigned to the same elements, and redundant explanations are omitted.

[0083] Thus, if the thickness of the magnetic body 30 at the portion not overlapping with the coil pattern CP is increased, higher magnetic characteristics can be obtained. In the example shown in Figure 8 , the Z-direction position of the boundary (10B) between the first resin layer 10 and the magnetic body 30 at the portion not overlapping with the coil pattern CP is included within the height range of the coil pattern CP. Accordingly, higher magnetic characteristics can be obtained.

[0084] As described above, the preferred embodiments of the present disclosure have been described, but the present disclosure is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present disclosure, and of course they are also included in the scope of the present disclosure.

[0085] For example, it may also be possible to add the second resin layer 20 shown in Figure 4 to the coil component 1 shown in Figure 5 or the coil component 1A shown in Figure 7 .

[0086] The technology of the present disclosure includes the following structural examples, but is not limited thereto.

[0087] A coil component according to an embodiment of the present disclosure includes: a coil pattern including a seed portion and a main body portion, the seed portion including resin and having first and second surfaces located on opposite sides, the main body portion being laminated on the second surface of the seed portion and made of a metal material; a magnetic body covering the coil pattern; a first resin layer located between the coil pattern and the magnetic body and including spherical filler particles and an adhesive resin, the coil pattern being embedded in the first resin layer such that the first surface of the seed portion is exposed from the first resin layer. Accordingly, since the coil pattern and the first resin layer are in close contact, voids are not easily generated around the coil pattern.

[0088] In the above coil component, the thickness of the main body portion may also be thicker than the thickness of the seed portion. Accordingly, the resistance value of the coil pattern can be reduced.

[0089] In the above coil component, it may also be that the average particle diameter of the filler particles is less than 5 μm, and the thickness of the first resin layer between the coil pattern and the magnetic body is thinner than the thickness of the coil pattern. Accordingly, the overall thickness of the coil component can be made thinner.

[0090] In the above coil component, it may also be that the average particle diameter of the filler particles is 5 μm or more, and the thickness of the first resin layer between the coil pattern and the magnetic body is thicker than the thickness of the coil pattern. Accordingly, the filling rate of the filler particles can be ensured, and the filler particles can be uniformly dispersed.

[0091] The above coil component may further include a second resin layer located on the opposite side of the magnetic body from the first resin layer. Accordingly, the magnetic body can be protected from both sides.

[0092] In the above coil component, the second resin layer may also include filler particles and an adhesive resin. Accordingly, the strength of the second resin layer can be improved. In addition, the magnetic body can be bonded to other components through the second resin layer.

[0093] In the above coil component, it may also be that the magnetic body is a ferrite sintered body, and the ferrite sintered body is an aggregate of a plurality of divided single pieces. Accordingly, the magnetic permeability of the magnetic body can be improved, and changes in magnetic characteristics can be suppressed.

[0094] In the above coil component, at least a part of the adhesive resin of the first resin layer may also penetrate into the gaps between the single pieces of the ferrite sintered body. Accordingly, since the single pieces are bonded by the adhesive resin, the strength of the magnetic body can be improved.

[0095] In the above-described coil component, the magnetic body may also be a magnetic resin layer containing flat magnetic powder and an adhesive resin. Accordingly, not only is the processing of the coil component made easy, but the entire coil component can be made flexible.

[0096] In the above-described coil component, the first resin layer may also include a first region on the magnetic body side and a second region in which the coil pattern is embedded. Accordingly, the adhesion of the first resin layer to the coil pattern and the magnetic body is improved.

[0097] In the above-described coil component, it may also be that the magnetic resin layer contains a curing agent, and the first region contains the same curing agent as the curing agent contained in the magnetic resin layer. Accordingly, the heat resistance and moisture resistance of the first resin layer can be improved.

[0098] In the above-described coil component, the concentration of the curing agent contained in the first region may also be lower than the concentration of the curing agent contained in the magnetic resin layer. Accordingly, the embedding characteristics of the first resin layer can be ensured.

[0099] In the above-described coil component, the ratio of the flat magnetic powder contained in the magnetic resin layer to the adhesive resin contained in the magnetic resin layer may also be greater than the ratio of the filler particles contained in the first resin layer to the adhesive resin contained in the first resin layer. Accordingly, the embedding characteristics of the coil pattern can be ensured, and a high inductance can be obtained.

[0100] An IC card according to an embodiment of the present disclosure includes the above-described coil component. Accordingly, a thin-type IC card can be provided.

Claims

1. A coil component, wherein: have: a coil pattern including a seed portion and a main body portion, wherein the seed portion includes a resin and has a first surface and a second surface located on opposite sides to each other, and the main body portion is stacked on the second surface of the seed portion and is composed of a metal material; a magnetic body covering the coil pattern; as well as a first resin layer, which is located between the coil pattern and the magnetic body and contains spherical filler particles and a binder resin, The coil pattern is embedded in the first resin layer such that the first surface of the seed portion is exposed from the first resin layer.

2. The coil component according to claim 1, wherein The body portion is thicker than the seed portion.

3. The coil component according to claim 1, wherein The average particle size of the filler particles is less than 5 μm, A thickness of the first resin layer between the coil pattern and the magnetic body is thinner than a thickness of the coil pattern.

4. The coil component according to claim 1, wherein The average particle size of the filler particles is 5 μm or more. The thickness of the first resin layer between the coil pattern and the magnetic body is thicker than the thickness of the coil pattern.

5. The coil component according to claim 1, wherein The invention further includes a second resin layer located on a surface of the magnetic body opposite to the first resin layer.

6. The coil component according to claim 5, wherein The second resin layer includes filler particles and a binder resin.

7. The coil component according to claim 1, wherein The magnetic body is a ferrite sintered body, The ferrite sintered body is an aggregate of a plurality of divided pieces.

8. The coil component according to claim 7, wherein The binder resin of the first resin layer infiltrates at least a portion of the gaps between the individual pieces of the ferrite sintered body.

9. The coil component according to claim 1, wherein The magnetic body is a magnetic resin layer including flat magnetic powder and a binder resin.

10. The coil component according to claim 9, wherein The first resin layer includes a first region located on the magnetic body side and a second region in which the coil pattern is embedded.

11. The coil component according to claim 10, wherein The magnetic resin layer contains a curing agent, The first region contains the same curing agent as the curing agent contained in the magnetic resin layer.

12. The coil component according to claim 11, wherein The concentration of the curing agent contained in the first region is lower than the concentration of the curing agent contained in the magnetic resin layer.

13. The coil component according to claim 9, wherein A ratio of the flat magnetic powder contained in the magnetic resin layer to the binder resin contained in the magnetic resin layer is greater than a ratio of the filler particles contained in the first resin layer to the binder resin contained in the first resin layer.

14. An IC card, wherein: A coil component according to any one of claims 1 to 13 is provided.

Images