Coil component and IC card equipped therewith

Abstract

In a coil component having a magnetic material and a coil pattern, the decrease in the Q value is suppressed. [Solution] The coil component 1 comprises a sheet-like member containing a magnetic material 30, a resin layer 10 arranged to overlap the sheet-like member, and a coil pattern CP located between the sheet-like member containing the magnetic material 30 and the resin layer 10, which circulates over multiple turns including a turn 216. Each turn of the coil pattern CP has a surface S1 covered by the resin layer 10 and a surface S2 facing the sheet-like member containing the magnetic material 30. The surface S2 of turn 216 and the sheet-like member containing the magnetic material 30 are spaced apart.

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a coil component in which a coil pattern that winds around a plurality of turns is formed on a substrate made of a magnetic material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when each turn constituting the coil pattern is in contact with the magnetic material, there is a case where desired coil characteristics cannot be obtained due to a decrease in the Q value.

[0005] The present disclosure describes a technique for suppressing a decrease in the Q value in a coil component having a magnetic material and a coil pattern.

Means for Solving the Problems

[0006] A coil component according to an embodiment of the present disclosure includes a sheet-like member including a magnetic material, a resin layer disposed so as to overlap the sheet-like member, and a coil pattern that is located between the sheet-like member and the resin layer and winds around a plurality of turns including a first turn. Each turn of the coil pattern has a first surface covered with the resin layer and a second surface facing the sheet-like member, and the second surface of the first turn and the sheet-like member are separated from each other.

Effects of the Invention

[0007] According to this disclosure, a technique is provided for suppressing a decrease in the Q value in a coil component having a magnetic material and a coil pattern. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic perspective view showing the external appearance of an IC card 2 equipped with a coil component according to one embodiment of the present disclosure. [Figure 2] Figure 2 is an exploded perspective view illustrating the structure of an IC card 2 equipped with a coil component 1. [Figure 3] Figure 3 is a schematic cross-sectional view illustrating the structure of an IC card 2 equipped with a coil component 1. [Figure 4] Figure 4 is a schematic perspective view of the IC module 60 as seen from the back side. [Figure 5] Figure 5 is a schematic diagram showing the state in which the IC card 2 and the card reader 6 are communicating. [Figure 6] Figure 6 is a schematic plan view illustrating the configuration of the coil pattern CP. [Figure 7] Figure 7 is a schematic cross-sectional view along the CC line shown in Figure 6. [Figure 8] Figure 8 is a schematic cross-sectional view of the coil component according to the first modification. [Figure 9] Figure 9 is a schematic cross-sectional view of the coil component according to the second modification. [Figure 10] Figure 10 is a schematic cross-sectional view of the coil component according to a third modification. [Figure 11] Figure 11 is a cross-sectional view showing a portion of the coil component 1 in more detail. [Figure 12] Figure 12 is a schematic plan view showing the shape of the second circular section 22 in a modified form. [Modes for carrying out the invention]

[0009] Preferred embodiments of this disclosure will be described in detail below with reference to the attached drawings.

[0010] Figure 1 is a schematic perspective view showing the external appearance of an IC card 2 equipped with a coil component according to one embodiment of the present disclosure.

[0011] The IC card 2 shown in Figure 1 is a plate-like body with the Y direction as the longitudinal direction, the X direction as the short 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, which will be described later, is built into the IC card 2, and the terminal electrodes E of the IC module are exposed on the upper surface 2a of the IC card 2.

[0012] Figures 2 and 3 are a substantially exploded perspective view and a substantially cross-sectional view, respectively, illustrating the structure of the IC card 2 equipped with the coil component 1 according to this embodiment.

[0013] The IC card 2 shown in Figures 2 and 3 has a structure in which a plastic plate 40, a coil component 1, and a metal plate 50 are stacked in this order from the back surface 2b to the top surface 2a. The metal plate 50 constitutes the first card base material, and the plastic plate 40 constitutes the second card base material. The coil component 1 is composed of a magnetic material 30 which is a sheet-like member, and a coil pattern CP and a resin layer 10 which are arranged on one (+Z direction) surface side of the magnetic material 30. The magnetic material 30 and the resin layer 10 overlap in the Z direction, and the coil pattern CP is arranged between them. The coil component 1 is arranged between the metal plate 50 and the plastic plate 40 such that the magnetic material 30 faces the metal plate 50 and the resin layer 10 faces the plastic plate 40. Part or all of the coil pattern CP may be embedded in the resin layer 10.

[0014] The magnetic material 30 and the metal plate 50 are provided with 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 together via an adhesive layer 71. The metal plate 50 and the coil component 1 are bonded together 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 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 using a metal plate for its main body.

[0016] Figure 4 is a schematic perspective view of the IC module 60 seen from the back side.

[0017] As shown in FIG. 4, the IC module 60 includes a module substrate 61, an IC chip 62 mounted or incorporated 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. The protective resin 64 is made of an insulating member. On the surface side of the module substrate 61, the terminal electrode E shown in FIG. 1 is provided. The IC module 60 having such a configuration is accommodated in the through hole 51 provided in the metal plate 50. When the IC module 60 is accommodated in the through hole 51, a part of the coupling coil 63 of the IC module 60 and a part of the coil pattern CP are electromagnetically coupled. And a part of the coil pattern CP that is electromagnetically coupled with the coupling coil 63 is connected to another part of the coil pattern CP that functions as an antenna coil. As a result, communication between the IC module 60 and the outside is enabled via the coil pattern CP.

[0018] Thereby, as shown in FIG. 5, 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. That is, 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.

[0019] Figure 6 is a schematic plan view illustrating the configuration of the coil pattern CP. Note that line AA in Figure 6 indicates the cross-sectional position shown in Figure 3.

[0020] The coil pattern CP shown in Figure 6 is composed of a conductor pattern consisting of multiple turns. Both the outer peripheral end CPa and the inner peripheral end CPb of the coil pattern CP are open and not connected to any other conductive members. Therefore, the coil pattern CP is electrically floating.

[0021] Each of the multiple turns constituting the coil pattern CP has a first circumferential portion 21 that circulates in a first direction along the outer edge of the magnetic material 30 so as to overlap with the magnetic material 30, which is a sheet-like member, and a second circumferential portion 22 that is located in a first opening region 210 surrounded by the first circumferential portion 21 and circulates in a second direction opposite to the first direction. The coil pattern CP may have one or more turns that do not include one or both of the first circumferential portion 21 and the second circumferential portion 22. Here, if position B shown in Figure 6 is defined as the start and end point of each turn, one end of the second circumferential portion 22 and one end of the first circumferential portion 21 in each turn are connected via a first connecting portion 23, and the other end of the second circumferential portion 22 in each turn and the other end of the first circumferential portion 21 of another turn adjacent to that turn are connected via a second connecting portion 24.

[0022] A portion of the second circular portion 22 of the coil pattern CP overlaps with the through-hole 31 of the magnetic material 30. As a result, a portion of the second circular portion 22 of the coil pattern CP 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 material 30. In the example shown in Figure 6, only a portion of the second circular portion 22 of the coil pattern CP overlaps with the through-hole 31 of the magnetic material 30, and the remaining portion of the second circular portion 22 overlaps with the magnetic material 30, but the entire second circular portion 22 of the coil pattern CP may overlap with the through-hole 31 of the magnetic material 30. Also, in the example shown in Figure 6, the entire second opening region 220 surrounded by the second circular portion 22 overlaps with the through-hole 31 of the magnetic material 30. Furthermore, in the example shown in Figure 6, the second circumferential portion 22 of the coil pattern CP is approximately circular, and the edges of the through-holes 31 in the magnetic material 30 are approximately square. Therefore, the second circumferential portion 22 does not follow the edges of the through-holes 31 in the magnetic material 30. As a result, the second circumferential portion 22 is less affected by the metal plate 50 through the through-holes 31 in the magnetic material 30, and losses due to the metal plate 50 are reduced.

[0023] In the example shown in Figure 6, the number of turns in the conductor pattern constituting the coil pattern CP is approximately 6 turns. The second circumferential portion 22 of the coil pattern CP is a portion that circulates so as to protrude toward the first opening region 210 surrounded by the first circumferential portion 21 of the coil pattern CP. In other words, each turn of the coil pattern CP is composed of a first circumferential portion 21 of less than 1 turn, a second circumferential portion 22 of less than 1 turn, and a first connecting portion 23 and a second connecting portion 24 that connect them.

[0024] The first loop portion 21 of the coil pattern CP functions as an antenna coil that connects to an external card reader during actual use. The second loop portion 22 of the coil pattern CP functions as a coupling coil that connects to the IC module 60. The second loop portion 22 of the coil pattern CP may also function as part of an antenna coil that connects to an external card reader. For example, if the resonant frequency of the coil pattern CP is set to 13.56 MHz or a frequency band near 13.56 MHz, near-field communication (NFC) becomes possible between an external card reader and the IC card 2. [0] Also, if the outer peripheral end CPa of the coil pattern CP is taken as the starting point and the inner peripheral end CPb of the coil pattern CP is taken as the ending point, when viewed from the direction shown in Figure 6, the first loop portion 21 of the coil pattern CP rotates counterclockwise, and the second loop portion 22 of the coil pattern CP rotates clockwise. In other words, the rotation directions of the first loop portion 21 and the second loop portion 22 are opposite to each other. As a result, for example, in turn 211 where the first circling section 21 is located on the outermost circumference of each turn, the second circling section 22 will be located on the innermost circumference of each turn.

[0025] Figure 7 is a schematic cross-sectional view along the CC line shown in Figure 6.

[0026] In the example shown in Figure 7, the first circular portion 21 of the coil pattern CP is composed of six turns 211 to 216. Of these, turn 211 is the outermost turn, and turn 216 is the innermost turn. The cross-section of each turn 211 to 216 has surfaces S1 to S3. Here, surface S1 is an XY plane oriented in the +Z direction, and surface S2 is an XY plane oriented in the -Z direction. Surfaces S1 and S2 do not need to be perfect XY planes; they may have some degree of inclination or curvature with respect to the XY plane. Surface S3 is the side surface connecting surfaces S1 and S2. In the schematic diagram shown in Figure 7, surface S3 extends parallel to the Z direction, but surface S3 may have some degree of inclination with respect to the Z direction, and as will be described later, surface S3 may be a curved surface. In the example shown in Figure 7, surfaces S1 and S3 are in contact with the resin layer 10, but a portion of surface S3 may be exposed without contacting the resin layer 10. Also, in the example shown in Figure 7, the resin layer 10 and the magnetic material 30 are in contact in the portion where the coil pattern CP does not exist.

[0027] In the example shown in Figure 7, the thickness T1 in the Z direction (axial direction) of turns 211 to 216 is not constant. Turn 211 has the thickest thickness T1, and the thickness T1 decreases as you move inward from turn 211, with turn 216 having the thinnest thickness T1. Here, thickness T1 is defined by the distance in the Z direction between surfaces S1 and S2. The surfaces S1 of turns 211 to 216 may be at the same position in the Z direction. In contrast, the surfaces S2 of turns 211 to 216 are at different positions in the Z direction. Specifically, the surface S2 of turn 211 is closest to the magnetic material 30, and the distance between the surface S2 and the magnetic material 30 increases as you move inward from turn 211, with the surface S2 of turn 216 being the furthest from the magnetic material 30. Furthermore, while the surface S2 of turn 211 is in contact with the magnetic material 30, the surfaces S2 of turns 212-216 face the magnetic material 30 but are not in contact with it, and are separated from it. As a result, a gap 80 consisting of an air layer is formed between the surfaces S2 of turns 212-216 and the magnetic material 30. A non-magnetic material other than air may be filled in part of the gap 80. In the example shown in Figure 7, the magnetic material 30 is exposed in the gap 80.

[0028] Alternatively, not only the surface S2 of the outermost turn 211, but also the turns 212 and 213 located on the outer side may be in contact with the magnetic material 30. Furthermore, in turns where the surface S2 separates from the magnetic material 30, the entire surface S2 may be separated, or a part of the surface S2 may be separated while another part of the surface S2 is in contact with the magnetic material 30.

[0029] In the example shown in Figure 7, the distance T2 in the Z direction of the gap 80 increases from turn 212 to turn 216. For some gaps 80, the distance T2 in the Z direction may be the same. For example, the distance T2 in the Z direction of the gap 80 corresponding to turn 215 and the distance T2 in the Z direction of the gap 80 corresponding to turn 216 may be approximately the same. Here, distance T2 is defined by the distance in the Z direction between the surface S2 and the magnetic material 30. If the distance in the Z direction between the surface S2 and the magnetic material 30 is not constant, distance T2 may be defined by the maximum distance in the Z direction between the surface S2 and the magnetic material 30. The magnitude of T1+T2 may be approximately constant in turns 211 to 216. The thickness T1 in turns 211 to 216 may be greater than the distance T2 in the Z direction of the gap 80. In other words, the thickness T1 of the coil pattern CP is minimized at turn 216, and the distance T2 of the gap 80 is maximized at turn 216, however, the thickness T1 of turn 216 may be greater than the distance T2 of the gap 80 formed by turn 216.

[0030] Furthermore, the distance T2 in each turn may vary depending on the position in the circumferential direction. For example, for the outermost turn 211, the surface S2 may be in contact with the magnetic material 30 in the 1 / 2 turn on the outer side, and the surface S2 may be separated from the magnetic material 30 in the remaining 1 / 2 turn on the inner side. In this case, the surface S2 separates from the magnetic material 30 at the position 1 / 2 turn after starting from the outer edge CPa of the coil pattern CP. The point where the surface S2 separates from the magnetic material 30 may be on the inner side of the position 1 / 2 turn after starting from the outer edge CPa of the coil pattern CP, or it may be on the outer side of the position 1 / 2 turn after starting from the outer edge CPa of the coil pattern CP. Alternatively, for turn 211, the surface S2 may be in contact with the magnetic material 30 over its entire circumference, and for turn 212, the surface S2 may be in contact with the magnetic material 30 in the half turn located on the outer circumference, while the surface S2 may be separated from the magnetic material 30 in the remaining half turn located on the inner circumference. In this case as well, the position where the surface S2 separates from the magnetic material 30 is not particularly limited.

[0031] As shown in Figure 7, in the example, there is an air gap 80 between the surface S2 of turns 212-216 and the magnetic material 30. This suppresses the decrease in the Q value due to the proximity of the coil pattern CP and the magnetic material 30. The Q value can be adjusted by the distance T2 of the air gap 80. Moreover, the air gap 80 also plays a role in increasing the insulation resistance between adjacent turns. Such an air gap 80 can be obtained by adjusting various parameters in the manufacturing process of the coil pattern CP, as well as by adjusting various parameters in the bonding process between the resin layer 10 in which the coil pattern CP is embedded and the magnetic material 30. Methods for forming the coil pattern CP include electrolytic plating and printing, and in these cases, the shape of turns 211-216 can be made into the shape shown in Figure 7 by adjusting the plating conditions or printing conditions.

[0032] Furthermore, in the example shown in Figure 7, the thickness T1 of the outermost turn 211 is sufficiently secured, which also reduces the DC resistance of the coil pattern CP. Moreover, the thinner the thickness T1 and the higher the current density of a turn (e.g., turn 216), the larger the distance T2 of the air gap 80, thus more effectively suppressing the decrease in the Q value. In addition, since most of the surface of the coil pattern CP, including surfaces S1 and S3, is covered with the resin layer 10, the insulation resistance between turns is also increased compared to the case where the entire coil pattern CP is embedded in a magnetic material.

[0033] Figure 8 is a schematic cross-sectional view of the coil component according to the first modification.

[0034] The first modified example shown in Figure 8 differs from the structure shown in Figure 7 in that a non-magnetic protective layer 32 made of PET (polyethylene terephthalate) resin, PI (polyimide) resin, PETG (glycol-modified polyethylene terephthalate) resin, etc., is added. The magnetic material 30 and the protective layer 32 constitute a sheet-like member 33. In this case, the resin layer 10 and the protective layer 32 included in the sheet-like member 33 are in contact with each other in the areas where the coil pattern CP does not exist. Adding such a protective layer 32 enhances mechanical strength and reliability. In addition, the overall distance between the magnetic material 30 and the coil pattern CP is increased, further suppressing the decrease in the Q value. In the first modified example shown in Figure 8, the surface S2 of turn 211 is in contact with the protective layer 32 included in the sheet-like member 33, while the surfaces S2 of turns 212 to 216 are not in contact with the protective layer 32, and they are separated. In the first modified example shown in Figure 8, the protective layer 32 is exposed in the void 80.

[0035] Figure 9 is a schematic cross-sectional view of the coil component according to the second modification.

[0036] In the second modified example shown in Figure 9, contrary to the example shown in Figure 7, the thickness T1 of the outermost turn, turn 211, is the thinnest, and the thickness T1 increases as you move inward from turn 211, with the thickness T1 of the innermost turn, turn 216, being the thickest. Furthermore, while the surface S2 of turn 216 is in contact with the magnetic material 30, the surfaces S2 of turns 211 to 215 face the magnetic material 30 but are not in contact with it, and a gap 80 consisting of an air layer is formed between them. As illustrated by the second modified example shown in Figure 9, the relationship of the thicknesses of turns 211 to 216 may be the opposite of the example shown in Figure 7.

[0037] Figure 10 is a schematic cross-sectional view of the coil component according to a third modification.

[0038] In the third modified example shown in Figure 10, the thickness T1 of the outermost turn 211 and the innermost turn 216 is the thickest, and the thickness T1 decreases as you move towards the turns located in the center in the radial direction perpendicular to the coil axis. The surfaces S2 of turns 211 and 216 are in contact with the magnetic material 30, while the surfaces S2 of turns 212 to 215 face the magnetic material 30 but are not in contact with it, and a gap 80 consisting of an air layer is formed between them. As illustrated by the third modified example shown in Figure 10, the relationship of the thicknesses of turns 211 to 216 is not limited to the examples shown in Figures 7 and 9.

[0039] Figure 11 is a cross-sectional view showing a portion of the coil component 1 in more detail.

[0040] Figure 11 shows cross-sections of turns 211 and 212 of the coil pattern CP. In the example shown in Figure 11, the coil pattern CP is composed of a main body M, which is a metal layer, and a seed portion CR, which is a conductive resin layer. Surfaces S1 and S3 of the coil pattern CP are made of the main body M, and surface S2 of the coil pattern CP is made of the seed portion CR. In other words, the coil pattern CP has a laminated structure that includes a metal layer on the surface S1 side and a conductive resin layer on the surface S2 side. The seed portion CR, which is a conductive resin layer, has a higher electrical resistance than the main body M, which is a metal layer. Therefore, by making the surface S2 of the coil pattern CP a seed portion CR, the occurrence of short-circuit failures via the magnetic material 30 between adjacent turns is suppressed. Moreover, in the example shown in Figure 11, since a gap 80 is formed between the surface S2 of turn 212 and the magnetic material 30, even when the surface S2 of turn 211 is in contact with the magnetic material 30, the occurrence of short-circuit failures via the magnetic material 30 between turn 211 and turn 212 is more effectively suppressed.

[0041] The resin layer 10 may contain insulating inorganic fillers F1 to F3 and a binder resin R. The resin layer 10 containing the inorganic fillers F1 to F3 protects the coil pattern CP and adjusts the capacitance generated between adjacent turns of the coil pattern CP. The inorganic fillers F1 to F3 are all spherical, but have different particle sizes. Inorganic filler F1 is a small-diameter filler with a first particle size distribution where the average value is the first particle size. Inorganic filler F2 is a medium-diameter filler with a second particle size distribution where the average value is the second particle size which is larger than the first particle size. Inorganic filler F3 is a large-diameter filler with a third particle size distribution where the average value is the third particle size which is larger than the second particle size. By using three types of inorganic fillers F1 to F3 with different particle size distributions in this way, the filling rate of the inorganic fillers in the resin layer 10 can be increased. However, it is not mandatory to use multiple inorganic fillers with different particle size distributions; a single type of inorganic filler with the same particle size distribution may be used.

[0042] The inorganic fillers F1 to F3 may be made from non-magnetic inorganic materials such as alumina, aluminum hydroxide, talc, magnesium hydroxide, silica, calcium carbonate, barium titanate, zirconium titanate, or zinc zirconate titanate, or from magnetic materials such as ferrite or Fe-based alloy magnets. The inorganic fillers F1 to F3 may be the same as each other, or they may differ in some respects. The dielectric constant of the inorganic fillers F1 to F3 may be higher than that of the binder resin R.

[0043] Examples of binder resin materials include acrylic resins, polyester resins, polyethylene resins, polyvinyl chloride resins, polyvinyl butyral resins, polyurethane resins, polyester urethane resins, cellulose resins, ABS (acrylonitrile-butadiene-styrene) resins, nitrile-butadiene rubbers, styrene-butadiene rubbers, epoxy resins, phenolic resins, amide resins, polyester elastomers, and polyamide elastomers.

[0044] In the example shown in Figure 11, the void 80 extends even to the area where the coil pattern CP is not provided. Thus, the void 80 may exist not only between the coil pattern CP and the magnetic material 30, but also between the resin layer 10 and the magnetic material 30.

[0045] In the example shown in Figure 11, the entire surface S3 of the coil pattern CP does not extend parallel to the Z direction, but rather has a curved surface. As a result, the pattern width of the coil pattern CP in the radial direction perpendicular to the coil axis direction becomes narrower as it moves away from the magnetic material 30. By making the cross-sectional shape of the coil pattern CP such, the packing rate of inorganic fillers F1 to F3 between turns can be increased.

[0046] Figure 12 is a schematic plan view showing the shape of the second circular section 22 in a modified form.

[0047] In the example shown in Figure 12, the second circumferential portion 22 of the coil pattern CP is elliptical. Specifically, the diameter Dy in the Y direction of the second opening region 220 of the second circumferential portion 22 is larger than the diameter Dx in the X direction of the second opening region 220 of the second circumferential portion 22. This makes it possible to increase the coupling coefficient between the second circumferential portion 22 of the coil pattern CP and the coupling coil 63 of the IC module 60, while also reducing the influence of eddy currents generated near the through-hole 51 of the metal plate 50, even if a misalignment occurs in the Y direction between the coil pattern CP and the IC module 60.

[0048] While preferred embodiments of this disclosure have been described above, it goes without saying that this disclosure is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of this disclosure, and such modifications are also included within the scope of this disclosure.

[0049] The technology relating to this disclosure includes, but is not limited to, the following configuration examples.

[0050] A coil component according to one embodiment of the present disclosure comprises a sheet-like member containing a magnetic material, a resin layer arranged to overlap the sheet-like member, and a coil pattern located between the sheet-like member and the resin layer, which circulates over multiple turns including a first turn. Each turn of the coil pattern has a first surface covered by the resin layer and a second surface facing the sheet-like member, and the second surface of the first turn and the sheet-like member are spaced apart. As a result, the distance between the first turn and the magnetic material is increased, which suppresses a decrease in the Q value of the coil pattern.

[0051] In the above coil component, an air gap may exist between the second surface of the first turn and the sheet-like member. This more effectively suppresses the decrease in the Q value and increases the insulation resistance between adjacent turns.

[0052] In the above coil component, the magnetic material may be exposed in the void. This makes it possible to reduce the overall thickness. Alternatively, in the above coil component, the sheet-like member may include a magnetic material and a non-magnetic protective layer located between the magnetic material and the resin layer, and the protective layer may be exposed in the void. This improves the reliability of the coil component.

[0053] In the above-described coil component, the coil pattern further includes a second turn, and the second surface of the second turn and the sheet-like member may be in contact with each other. This makes it possible to reduce the overall thickness.

[0054] In the above coil component, the first turn may be either the outermost turn or the innermost turn, and the second turn may be the other of the outermost or innermost turn. Such a shape can be obtained by adjusting the parameters when manufacturing the coil pattern.

[0055] In the above-described coil component, the coil pattern further includes a third turn located between the first and second turns, and the second surface of the third turn and the sheet-like member are spaced apart. The distance between the second surface of the first turn and the sheet-like member may be greater than the distance between the second surface of the third turn and the sheet-like member. This makes it possible to adjust the Q value of the coil pattern.

[0056] In the above coil component, the thickness of the second turn may be greater than the thickness of the first turn. This makes it possible to reduce the DC resistance of the coil pattern.

[0057] In the above coil component, the thickness of the first turn may be greater than the distance between the second surface of the first turn and the sheet-like member. This makes it possible to reduce the DC resistance of the coil pattern.

[0058] In the above-described coil component, the pattern width of the coil pattern in the direction perpendicular to the coil axis direction may have a shape that becomes narrower as it moves away from the sheet-like member. This makes it easier to fill the spaces between turns of the resin layer.

[0059] In the above-described coil component, the coil pattern may have a laminated structure that includes a metal layer on the first surface side and a conductive resin layer on the second surface side. This more effectively suppresses the occurrence of short-circuit failures via magnetic material between adjacent turns.

[0060] In the above coil component, the resin layer may contain an inorganic filler. This makes it possible to adjust the capacitance between adjacent turns in the coil pattern.

[0061] An IC card according to one embodiment of the present disclosure comprises the above-described coil component. This makes it possible to provide an IC card having desired characteristics.

[0062] The above IC card further comprises a first card substrate made of metal and a second card substrate made of resin, and the coil component may be arranged between the first and second card substrates such that the sheet-like member faces the first card substrate and the resin layer faces the second card substrate. This makes it possible to provide a metal IC card that can communicate with an external card reader from the second card substrate side. [Explanation of Symbols]

[0063] 1. Coil component 2 IC cards 2a Top of IC card 2b Back of IC card 6 Card Readers 10 resin layer 21. First lap 22 Second lap 23. First connection section 24 Second Connection Section 30 Magnetic material 31 Through hole 32 Protective layer 33 Sheet-like member 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 80 void Turns 211-216 CP coil pattern Outer edge of CPa coil pattern CPb coil pattern inner edge CR Seed Section E terminal electrode F1~F3 Inorganic Filler M Main body R Binder Resin S1~S3 surface

Claims

1. A sheet-like member containing a magnetic material, A resin layer arranged to overlap with the aforementioned sheet-like member, A coil pattern located between the sheet-like member and the resin layer, which circulates over multiple turns including a first turn, Equipped with, Each turn of the coil pattern has a first surface covered with the resin layer and a second surface facing the sheet-like member. The second surface of the first turn and the sheet-like member are spaced apart. Coil components.

2. A gap consisting of an air layer exists between the second surface of the first turn and the sheet-like member. The coil component according to claim 1.

3. The magnetic material is exposed in the gap. The coil component according to claim 2.

4. The sheet-like member includes the magnetic material and a non-magnetic protective layer located between the magnetic material and the resin layer. The protective layer is exposed to the gap, The coil component according to claim 2.

5. The coil pattern further includes a second turn, The second surface of the second turn and the sheet-like member are in contact with each other. The coil component according to claim 1.

6. The first turn is either the outermost turn or the innermost turn. The second turn is the other of either the outermost turn or the innermost turn. The coil component according to claim 5.

7. The coil pattern further includes a third turn located between the first turn and the second turn, The second surface of the third turn and the sheet-like member are spaced apart. The distance between the second surface and the sheet-like member in the first turn is greater than the distance between the second surface and the sheet-like member in the third turn. The coil component according to claim 6.

8. The thickness of the second turn is greater than the thickness of the first turn. The coil component according to claim 5.

9. The thickness of the first turn is greater than the distance between the second surface of the first turn and the sheet-like member. The coil component according to claim 5.

10. The pattern width of the coil pattern in the direction perpendicular to the coil axis has a shape that becomes narrower as it moves away from the sheet-like member. The coil component according to claim 1.

11. The coil pattern has a laminated structure that includes a metal layer on the first surface side and a conductive resin layer on the second surface side. The coil component according to claim 1.

12. The resin layer contains an inorganic filler. The coil component according to claim 1.

13. An IC card comprising the coil component described in any one of claims 1 to 12.

14. A first card base material made of metal, A second card base material made of resin, Furthermore, The coil component is positioned between the first card substrate and the second card substrate such that the sheet-like member faces the first card substrate and the resin layer faces the second card substrate. The IC card according to claim 13.

Images