Dual interface card and manufacturing method thereof

Abstract

To provide a dual interface card configured to efficiently form an antenna at a low cost while securing electrical connection reliability between an IC module and the antenna and adhesiveness of the IC module to the card, and a manufacturing method of the dual interface card.SOLUTION: A dual interface card 1 includes: a card substrate 2; an antenna 8 having a plurality of first ends 81; and an IC module 7 having an IC chip and a plurality of terminals 73a. The IC module 7 is arranged in a recess 9 formed in the card substrate 2 so that the terminal 73a and the first end 81 facing each other may be electrically connected to each other. The first end 81 is configured by repeatedly folding an antenna wire 83 from an outer periphery of the recess 9 toward the center, and partially exposed to the recess 9. The first end 81 in a range from the outer periphery of the recess 9 toward the center is formed along contours of convex shapes that expand along a direction orthogonal to a direction from the outer periphery of the recess 9 toward the center.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dual interface card capable of contact and non-contact communication with an external device. [Background technology]

[0002] Conventional IC cards include contact IC cards, which input and output electrical signals through an external connection terminal on the card surface, and contactless IC cards, which input and output electrical signals via an antenna using electromagnetic induction or other methods. In addition to these, dual-interface cards, which combine the functions of both contact and contactless IC cards with a single IC chip, are also in use. Dual-interface cards can be used as contact IC cards, which are effective in preventing external leakage of input and output data during financial transactions, and as highly convenient contactless IC cards, which allow data to be exchanged in close proximity when entering and exiting a room or using a ticket gate at a station. For this reason, dual-interface cards are becoming increasingly popular in the market.

[0003] A dual interface card is manufactured as follows. First, as described in Patent Document 1, a card substrate including one or more core sheets is formed, and an area for embedding an IC module is cut from the surface of the card substrate. The IC module is then embedded in the area. Conductive wires are arranged on one of the one or more core sheets, and the conductive wires form a wound antenna for providing the contactless communication function and contact terminals that are in electrical contact with terminals of the IC module. The contact terminals are, for example, arranged in a meandering shape.

[0004] Furthermore, in Patent Document 2, in the manufacture of the above-mentioned dual interface card, electrode sections are provided in predetermined regions corresponding to the terminals of the IC module mounted in the recess, where both ends of the coated conductor wire are densely arranged while bending in a meandering shape from the outer periphery toward the center of the recess. Here, in the electrode section, the trajectory of the coated conductor wire between a first turning point and a subsequent second turning point protrudes toward the center of the recess at a central point relative to the first and second turning points, and for example, the trajectory is an arc or a broken line.

[0005] The antenna end portion for electrical connection with the terminal of the IC module typically has a meandering shape as shown in Fig. 9(a), as described in Patent Document 1. Here, the antenna wire 83 constituting the antenna 8 has approximately arc-shaped bends at its upper and lower ends, and the portion other than the bends is approximately linear along the vertical direction. Here, the IC module embedded in the card base typically has an approximately rectangular outer shape, and when the recess for embedding the IC module is formed by cutting with an end mill, the movement direction of the end mill for exposing the antenna end portion 81p is the vertical direction parallel to the linear portion of the antenna wire 83. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2019-219732 [Patent Document 2] Patent No. 6442003 Summary of the Invention [Problem to be solved by the invention]

[0007] At this time, as described in Patent Document 2, the blade of the end mill bites into a part of the antenna wire 83, causing a part of the antenna wire 83 to branch into a long, thin shape, as shown in Figure 9(b), which is an enlarged view of part C of the antenna end 81p in Figure 9(a). Such branched parts of the antenna wire 83 are sometimes called whiskers. If whiskers are formed, they may become pinched between the terminal of the IC module and the antenna end 81p, impairing the electrical connection between the IC module and the antenna 8. Furthermore, pinching the whiskers may cause the IC module to protrude from the surface of the card base, resulting in an IC card that does not comply with the specifications.

[0008] On the other hand, as exemplified in Patent Document 2, it is possible to tilt the linear portion of the antenna wire at the antenna end relative to the vertical direction, as shown in antenna end 81q in Figure 9(c). However, in this case, regions DS1 and DS2 where antenna wire 83 is not located are formed at the upper left and lower right of antenna end 81q. This effectively narrows the area available for electrical connection with the IC module. Furthermore, when adhering the IC module to the card base, regions DS1 and DS2 create gaps due to the absence of antenna wire 83, which may impair adhesion between the IC module and the card base. Furthermore, changing the linear portion of the antenna wire at the antenna end to an arc or bent line complicates the trajectory of the antenna wire, which increases the amount of antenna wire consumed and processing time. Therefore, it is preferable to increase the linear portion as much as possible.

[0009] Taking these factors into consideration, it is preferable to position the antenna end in as small an area as possible, while ensuring good electrical connection with the IC module and avoiding placement in areas that do not contribute to electrical connection with the IC module, in order to reduce material costs, improve the efficiency of the process of embedding the antenna wire into the card base, and reduce the aforementioned whiskers.

[0010] The present disclosure has been made in consideration of these circumstances, and aims to provide a dual interface card and a manufacturing method thereof that can form an antenna efficiently and at low cost while ensuring the reliability of the electrical connection between the IC module and the antenna and the adhesion of the IC module to the card. [Means for solving the problem]

[0011] According to this embodiment, a dual interface card capable of contact and contactless communication with an external device comprises a card base, an antenna having multiple ends arranged inside the card base, and an IC module having an IC chip and multiple terminals electrically connected to the IC chip, wherein the IC module is arranged in a recess provided in the card base so that the multiple terminals and multiple ends facing each other are electrically connected, and the multiple ends are formed by an antenna wire that constitutes the antenna, with a repeated folding structure from the outer periphery of the recess toward the center, and a portion of the folded structure is exposed in the recess, and the multiple ends in the range from the outer periphery toward the center of the recess are formed to follow the outline of a shape that expands convexly toward each other in a direction perpendicular to the direction from the outer periphery toward the center of the recess.

[0012] In addition, in a dual interface card according to another embodiment of the present invention, the recess may be composed of a first recess of approximately the same depth formed on the outer periphery, and a second recess formed closer to the center than the first recess and deeper than the first recess.

[0013] In a dual interface card according to another embodiment of the present invention, the IC module may have the plurality of terminals and the plurality of end portions that face each other electrically connected to each other via an anisotropic conductive film.

[0014] In addition, in a dual interface card according to another embodiment of the present invention, the outer periphery may be a substantially rectangular shape having sides that are substantially parallel to the short and long sides of the card base, and the multiple ends may be configured by a repeated folding structure extending from the outer periphery, which is a side of the recess that is substantially parallel to the short sides of the card base, toward the center by an antenna wire that constitutes the antenna.

[0015] In addition, in a dual interface card according to another embodiment of the present invention, among the multiple ends in the range from the outer periphery toward the center of the recess, the width of one region that overlaps with the multiple terminals in a direction perpendicular to the direction from the outer periphery toward the center of the recess may be larger than the width of another region in a direction perpendicular to the direction from the outer periphery toward the center of the recess.

[0016] In addition, in a dual interface card according to another embodiment of the present invention, the end portion is composed of a bent portion and a portion other than the bent portion, and the portion of the portion other than the bent portion that overlaps with the terminal is designated as a first portion, and the portion of the portion of the end portion other than the bent portion that does not overlap with the terminal is designated as a second portion, the arrangement pitch of the antenna wires in the first portion may be narrower than the arrangement pitch of the antenna wires in the second portion.

[0017] In a dual interface card according to another embodiment of the present invention, the portion of the end portion other than the bent portion may be inclined with respect to a straight line along the outer periphery.

[0018] In addition, in a dual interface card according to another embodiment of the present invention, the value of the angle of inclination of any of the terminals relative to a straight line along the outer periphery of a portion other than the bent portion may be 5 degrees or more and 20 degrees or less.

[0019] A method for manufacturing a dual interface card according to another embodiment of the present invention includes an antenna forming step of embedding an antenna wire in a first substrate while applying heat and pressure to form an antenna having a plurality of terminals on one surface of the first substrate; a laminating step of laminating a second substrate on the first substrate on which the antenna has been formed so as to sandwich the antenna; a punching step of punching the laminate of the first substrate and the second substrate into a card-sized card base; a recess forming step of forming a recess in the card base for embedding an IC module; and a step of preparing an IC module having an IC chip and a plurality of terminals electrically connected to the IC chip. and an IC module bonding process in which the IC module is bonded to the recess of the card base via a conductive adhesive so that the opposing terminals and the opposing ends are electrically connected, wherein the multiple ends are formed by an antenna wire that constitutes the antenna, with a repeated folding structure from the outer periphery of the recess toward the center, and a portion of the folding structure is exposed in the recess, and the multiple ends in the range from the outer periphery toward the center of the recess are formed to follow the outline of a shape that expands convexly toward each other in a direction perpendicular to the direction from the outer periphery toward the center of the recess. [Effects of the Invention]

[0020] According to this embodiment, it is possible to provide a dual interface card and a manufacturing method thereof that can form an antenna efficiently and at low cost while ensuring the reliability of the electrical connection between the IC module and the antenna and the adhesion of the IC module to the card. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 2 is a plan view illustrating the structure of the dual interface card according to the first embodiment. [Figure 2] 2 is a cross-sectional view illustrating the structure of a dual interface card corresponding to FIG. 1. FIG. [Figure 3] 4A and 4B are diagrams illustrating the details of the structure of the end portion of the antenna wire. [Figure 4] 1A and 1B are diagrams illustrating an IC module and a connection between the IC module and an antenna. [Figure 5] FIG. 5 is a plan view corresponding to FIG. 3 and illustrating the structure of a dual interface card according to a second embodiment. [Figure 6] FIG. 10 is a plan view corresponding to FIG. 3 and illustrating the structure of a dual interface card according to a third embodiment. [Figure 7] FIG. 10 is a plan view corresponding to FIG. 3 and illustrating the structure of a dual interface card according to a fourth embodiment. [Figure 8] FIG. 10 is a plan view corresponding to FIG. 3 and illustrating the structure of a dual interface card according to a fifth embodiment. [Figure 9] FIG. 1 is a diagram illustrating an antenna end according to a conventional technique. DETAILED DESCRIPTION OF THE INVENTION

[0022] An example of a dual interface card according to the present disclosure will be described below with reference to the drawings, etc. However, the dual interface card according to the present disclosure is not limited to the embodiments and examples described below.

[0023] The figures shown below are schematic illustrations. Therefore, the size and shape of each part are appropriately exaggerated to facilitate understanding. Furthermore, hatching indicating the cross section of a member is omitted as appropriate in each figure. The numerical values such as dimensions of each member and the names of materials described in this specification are examples of embodiments and are not limited to these, and may be selected and used as appropriate. In this specification, terms specifying shapes or geometric conditions, such as parallel, orthogonal, and perpendicular, are intended to include not only their strict meanings but also substantially the same state.

[0024] 1. First embodiment An example of a first embodiment of a dual interface card according to the present disclosure will now be described. For ease of explanation, an XYZ coordinate system will be established for the dual interface card 1. First, as shown in FIGS. 1(a) and 2(b), the Z axis is defined as the normal direction to the main surface of the dual interface card 1. The direction from the main surface on which the external connection terminals 71 of the IC module 7 are not arranged to the main surface on which the external connection terminals 71 are arranged is defined as the +Z direction or upward in the thickness direction, and the opposite direction is defined as the -Z direction or downward in the thickness direction.

[0025] When dual interface card 1 is viewed from the +Z direction, the line perpendicular to both short sides of dual interface card 1 and the Z axis is defined as the X axis, the direction from one short side closer to external connection terminal 71 toward the other short side is defined as the +X direction or rightward direction, and the opposite direction is defined as the -X direction or leftward direction. Furthermore, the axis perpendicular to the X and Z axes is defined as the Y axis, the direction from one long side farther from external connection terminal 71 toward the other long side is defined as the +Y direction or upward direction, and the opposite direction is defined as the -Y direction or downward direction.

[0026] FIG. 1(a) is a plan view of the dual interface card 1 as viewed from the +Z direction, and FIG. 1(b) is an enlarged view of the dual interface card 1 in FIG. 1(a) near the external connection terminal 71 to explain the arrangement of the antenna 8. To make the configuration of the antenna 8 easier to understand, the IC module 7 is omitted, and the antenna wire 83 embedded in the card base 2 is depicted with a solid line rather than a dashed line. In other words, the view is a perspective of the antenna 8. Normally, the antenna 8 is not exposed in the area outside the outer periphery 93 of the recess 9. Meanwhile, FIG. 2(a) is a cross-sectional view of the dual interface card 1 in FIG. 1(b) taken along line AA as viewed from the -Y direction. The IC module 7 is omitted from FIG. 2(a), and FIG. 2(b) is a view of the dual interface card 1 in FIG. 2(a) with the IC module 7 mounted.

[0027] As shown in FIG. 1(a), dual interface card 1 has the form of a generally rectangular thin plate with rounded corners when viewed from the +Z direction. Furthermore, on the surface of the dual interface card on the +Z direction side, an IC module 7 including external connection terminals 71 can be seen slightly to the upper left of the center, i.e., toward the -X direction and toward the +Y direction from the center. As shown in FIGS. 2(a) and 2(b), IC module 7 is embedded in a recess 9 formed in card base 2, and is positioned so that the surface of external connection terminals 71 on the +Z direction side is generally flush with the surface of card base 2 on the +Z direction side. This form of dual interface card 1 complies with ISO / IEC 7816, the international IC card standard.

[0028] As shown in Figure 2(a), the card base 2 that constitutes the card body of the dual interface card 1 is formed by laminating and integrating, in order from the -Z direction, an over-sheet layer 6, a core layer 5, a core layer 4, and an over-sheet layer 3. Typically, the over-sheet layers 6 and 3 are transparent substrates, and the core layers 5 and 4 are white substrates, but this is not limited thereto. In addition, an antenna wire 83 that constitutes the antenna 8 is disposed between the core layers 5 and 4 so as to be sandwiched between them.

[0029] The antenna wire 83 constituting the antenna 8 is partially exposed in a region of the bottom surface 91a of a first recess 91 that is formed relatively shallowly within the recess 9, and is completely buried inside the card base 2 in the rest of the region. In other words, the antenna wire 83 is buried inside the card base 2, but in the process of cutting the card base 2 to form the recess 9, a portion of the antenna wire 83 is cut along with the recess 9 to an extent that the portion does not break, and the cut surface of the antenna wire 83 is exposed on the bottom surface 91a of the first recess 91. In addition to the first recess 91 that is formed on the outer periphery 93 side and has approximately the same depth, the recess 9 further includes a second recess 92 that is formed closer to the center than the first recess 91 and is deeper than the first recess 91.

[0030] As shown in FIG. 2( b), the IC module 7 is embedded such that the external connection terminals 71 and the substrate 72 supporting the external connection terminals 71 are placed on the bottom surface 91 a of the first recess 91 of the recess 9, and the substrate 72 is mechanically joined to the bottom surface 91 a of the first recess 91 of the card base 2 via a conductive adhesive layer 11. Incidentally, the second recess 92 houses an IC chip body 74, which is a protruding portion of the IC module 7. Furthermore, a terminal 73 a electrically connected to an IC chip provided inside the IC module 7 is provided on the surface of the substrate 72 opposite the external connection terminals 71. At this time, due to the effect of heat and pressure when embedding the IC module 7 in the recess 9 of the card base 2, the antenna wire 83 exposed on the bottom surface 91 a and the terminal 73 a are electrically connected via the conductive adhesive layer 11.

[0031] Here, both ends of the antenna wire 83 of the antenna 8, which is mostly embedded inside the card base 2 and partially exposed from the first recess 91, have shapes as shown by the first end 81 and the second end 82 in FIG. 1(b). That is, the first end 81 and the second end 82, which are both ends of the antenna 8, are arranged side by side along the X-axis direction so that they partially overlap the first recess 91 in a plan view along the Z-axis. The first end 81 and the second end 82 each have a structure in which the antenna wire 83 is repeatedly folded from the outer periphery 93 of the first recess 91 toward the center of the recess 9. In other words, the first end 81 and the second end 82 are formed to have a structure known as a zigzag, meander, or bellows shape. In this way, by increasing the exposed area of the antenna wire 83 per unit area exposed in the recess 9, the reliability of the electrical connection between the terminal 73a of the IC module 7 and the antenna 8 can be improved.

[0032] Furthermore, at the first end 81 and the second end 82 of the antenna wire 83, portions other than the bent portions at the upper and lower ends of the folded structure are arranged along straight lines m1 and m2 parallel to sides 93a and 93b along the outer periphery 93 of the first recess 91, respectively, i.e., straight lines parallel to the Y axis. Furthermore, the first end 81 and the second end 82 are formed so as to follow the contours of shapes that expand convexly toward each other in a direction perpendicular to the direction from the outer periphery 93 toward the center of the recess 9. That is, the first end 81 and the second end 82 are formed so as to follow the contours of a figure surrounded by approximately arc-shaped curves that are convex toward the +Y direction and the -Y direction, respectively, and approximately straight line segments along the Y axis on the -X direction and the +X direction, respectively. This shape is sometimes referred to as a rice bag shape.

[0033] Furthermore, first exposed portion 84 and second exposed portion 85 of first end 81 and second end 82, which are portions of antenna wire 83 exposed from recess 9, are also formed to follow the outline of a figure surrounded by two curved lines and two line segments that form part of the above-mentioned figure. Therefore, first end 81 and second end 82 or first exposed portion 84 and second exposed portion 85 can be formed relatively compactly while reducing the amount of antenna wire 83 used, which makes it possible to efficiently embed antenna wire 83 in a base material while applying heat and pressure to it.

[0034] Furthermore, because the first end 81 and the second end 82 have such shapes, the length along the Y axis of the portion of the antenna wire 83 constituting them other than the bent portion of the folded structure is greatest at a predetermined point along the X axis of the first recess 91. Meanwhile, the terminals 73a and 73b of the IC module 7 embedded above the recess 9 are also arranged so as to be included in a predetermined range along the X axis of the first recess 91. Therefore, the antenna wires 83 of the first end 81 and the second end 82, which overlap the terminals 73a and 73b of the IC module 7 respectively along the Z axis, have a relatively long length along the Y axis other than the bent portion, thereby ensuring good electrical connection between the IC module 7 and the antenna 8.

[0035] On the other hand, the antenna wire 83 at the first end 81 and the second end 82 spaced along the X-axis from the terminals 73a and 73b of the IC module 7 has a relatively short length along the Y-axis other than the bent portions, which reduces the amount of antenna wire 83 used and improves the efficiency of the work of embedding the antenna wire 83 into the card base 2. Furthermore, since the cutting area of the antenna wire 83 is narrow, particularly when cutting the area along the outer periphery 93 of the first recess 91 and the vicinity of the boundary between the first recess 91 and the second recess 92 with an end mill, unintended branching of the antenna wire 83 can be suppressed.

[0036] The configuration of the dual interface card 1 of this embodiment and the manufacturing method thereof will be described in detail below.

[0037] (a) Card base The card base 2 refers to the card body excluding the IC module 7 that constitutes the dual interface card 1. As described above, the card base 2 typically has a configuration in which an over-sheet layer 6, a core layer 5, a core layer 4, and an over-sheet layer 3 are laminated in this order from one end of the card base 2 in the -Z direction in the thickness direction. Between the core layers 5 and 4, an antenna 8 wound in a loop shape and formed from a coated conductor wire or the like is disposed. The card base 2 may refer to both the card before the recess 9 is formed and the card after the recess 9 is formed, and may refer to both the card with and without the antenna 8. Furthermore, the first end 81 and the second end 82 of the antenna 8 are disposed with the antenna wire 83 processed into a predetermined shape, as described above.

[0038] However, the layer configuration of the card base 2 is not limited to this, and may be a three-layer configuration of an over-sheet layer, a core layer, and an over-sheet layer, a two-layer configuration of a core layer and a core layer, or a five-layer configuration of an over-sheet layer, a core layer, a core layer with an antenna formed thereon, a core layer, and an over-sheet layer, etc. Furthermore, printing or an embedded magnetic stripe may be applied to the surface of the over-sheet layer 3 or 6 of the card base 2 opposite to the core layer 4 or 5, or printing may be applied to the surface of the core layer 4 or 5 adjacent to the over-sheet layer 3 or 6.

[0039] From the standpoint of conforming to standards such as ISO / IEC 7816, the thickness of the card base 2 is preferably 0.76 mm or more and 0.84 mm or less, but may be outside this range.

[0040] (i) Core layer A wide variety of white or colored plastic sheets can be used for the core layers 4 and 5, including the following single films or composite films: polyethylene terephthalate (PET), PET-G (terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer), polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polycarbonate, polyamide, polyimide, cellulose diacetate, cellulose triacetate, polystyrene, ABS, polyacrylic ester, polypropylene, polyethylene, polyurethane, etc. The thickness of the core sheet can be selected appropriately taking into account the overall thickness of the card, but can be, for example, approximately 0.25 mm or more and 0.38 mm or less. As described below, antenna 8 must be positioned on the surface of either core layer 4 or 5 so that it is sandwiched between the two core layers.

[0041] (ii) Oversheet layer The over-sheet layers 3 and 6 are usually made of the same material as the core layer, but are often made of a transparent material with a thickness of about 0.05 mm to 0.10 mm. From the viewpoint of preventing curling when the laminate of the core layer and the over-sheet layer is integrated by heat pressing or the like, it is preferable that the over-sheet layers 3 and 6 have the same thickness, but they do not necessarily have to be the same.

[0042] The material for the over-sheet layer may be any material that is adhesive when heated, but even if the over-sheet layer itself is not adhesive when heated, the core layer and over-sheet layer can be integrated by additionally forming a layer of a known adhesive that generates adhesive force when heated between them. Furthermore, when dual interface card 1 is used as a magnetic card, magnetic tape may be embedded in advance by thermal transfer or the like into one or both of over-sheet layers 3 and 6 on the main surface opposite core layers 4 and 5.

[0043] (iii) Antenna sheet In this embodiment, as described below, the antenna 8 is formed on one surface of the core layer 5, and the first end 81 and the second end 82, which are the ends of the antenna wire 83 that constitute the antenna 8, are each processed into a predetermined shape and arranged. The formation of the antenna 8 on the core layer 5 is performed by applying a predetermined heat and pressure to the antenna wire 83, and embedding the antenna wire 83 in the core layer 5 while melting the core layer 5 and the coating of the antenna wire 83. The intermediate product in which the antenna 8 is embedded in the core layer 5 is sometimes referred to as an antenna sheet 12. The antenna sheet 12 can be distributed on the market by itself as a component for manufacturing the dual interface card 1, or a commercial model in which a sheet material such as the core layer 5 is supplied to a processor, who processes it into the antenna sheet 12 and delivers it to the supplier.

[0044] The method for forming the antenna sheet 12 will be described in detail later, but can be summarized as follows: First, a coated conductor coated with an insulating member is embedded into the surface of the core layer 5 using a winding former, starting from either one of the first ends 81 or 82 and ending at the other. That is, while applying a predetermined heat and pressure to the core layer 5, an antenna supply head is drawn into a loop shape as shown in FIG. 1(a), and antenna wires 83 supplied from the antenna supply head are sequentially embedded into the core layer 5.

[0045] Here, the first end 81 and the second end 82, which are either the start point or the end point of the antenna wire 83, are aligned in the left-right direction of the intended mounting position of the IC module 7 to form a predetermined shape described below, and are arranged so that portions of them overlap the terminals 73a and 73b of the IC module 7. Then, the winding forming machine cuts the antenna wire 83 after forming either the first end 81 or the second end 82, which are the end points of the antenna 8. In this way, the core layer 5 (antenna sheet 12) on which the antenna 8 is formed is obtained.

[0046] (iv) Antenna Terminals 73a and 73b of the IC module 7 are electrically connected to a first end 81 and a second end 82 of the antenna 8 formed on the core layer 5, respectively, so that the IC chip of the IC module 7 and the antenna 8 form a communication circuit for contactless communication. The communication circuit may be one that performs close-proximity communication using, for example, the 13.56 MHz HF frequency band specified in ISO / IEC 18092 or ISO / IEC 144443. Alternatively, the communication circuit may be one that performs communication using, for example, a 920 MHz UHF frequency band, a 125 kHz LF frequency band, or microwaves at 2.45 GHz.

[0047] When dual interface card 1 is held over an external device such as a reader / writer, a magnetic field generated by the reader / writer generates a current in the communication circuit, which supplies power to the IC chip. This enables the IC chip to be driven and allows it to send and receive information contactlessly with the reader / writer and to read and rewrite information from and to the memory.

[0048] The antenna wire 83 constituting the antenna 8 is typically formed of a coated conductor wire, which is a copper wire coated with an insulating material. Alternatively, copper alloy wires such as Cu-Ni, Cu-Cr, Cu-Zn, Cu-Sn, and Cu-Be, or various metal wires and metal alloy wires such as iron, stainless steel, and aluminum can also be selected. By using coated conductor wire, the dual interface card 1 can be manufactured more inexpensively than, for example, copper foil etching methods.

[0049] The diameter of the antenna wire 83 is not particularly limited as long as it can ensure the characteristics as a contactless communication circuit, but it can be, for example, 0.03 mm or more and 0.30 mm or less, and preferably 0.05 mm or more and 0.15 mm or less. By setting the diameter in the latter range, durability against heat pressure during embedding and external forces due to cutting can be improved, and good communication characteristics can be ensured.

[0050] Next, the configurations of the first end 81 and the second end 82 will be described in detail. Fig. 3 is an enlarged view illustrating the configuration of the first end 81 of the antenna 8 in Fig. 1(b). In Fig. 3, one end of the antenna 8 extending from the -X direction toward the +X direction subsequently forms a structure in which it is repeatedly folded back from the outer periphery 93 of the recess toward the center. That is, the antenna wire 83 extends from the -X direction toward the +X direction so that the folded back structure is repeated multiple times.

[0051] The folded structure has substantially arc-shaped bent portions at the ends on the +Y direction side and the -Y direction side, i.e., the upper and lower ends, and the portion other than the bent portion connecting the bent portion at the upper end and the bent portion at the lower end is substantially straight or curved. However, from the viewpoint of the efficiency of the process of embedding the antenna wire 83 in the core layer 5 and the saving of material for the antenna wire 83, it is preferable to form the portion other than the bent portion as substantially straight as possible.

[0052] Furthermore, the portions other than the bent portions of the folded structure are arranged along a straight line m1 that is substantially parallel to the Y-axis and that is aligned with the side 93a of the outer periphery 93 of the recess 9, and the zigzag arrangement pitch p1 between adjacent portions other than the bent portions is substantially constant. Furthermore, the entire first end 81 is formed to follow the outline of a figure enclosed by two predetermined curves and two line segments, with a maximum width H1 along the Y-axis and a width W1 along the X-axis. The figure has a substantially arc-shaped curve that is convex toward both the +Y and −Y directions, and has substantially straight line segments along the Y-axis on both the −X and +X directions. However, the convex shape is not limited to a substantially arc-shaped curve, and may be a combination of multiple substantially arc-shaped curves or a shape formed by stepped broken lines. It may also be formed by a combination of multiple line segments and multiple curves.

[0053] As a result, the length of the antenna wire 83 along the Y axis is shorter than H1 at the ends on the -X direction side and +X direction side of first end 81. Similarly, first exposed portion 84, which is part of first end 81 and where antenna wire 83 is actually exposed in first recess 91, is formed so as to follow the outline of a predetermined shape that is part of the above-mentioned shape. Furthermore, the length of the antenna wire 83 along the Y axis at the end on the -X direction side of first exposed portion 84, i.e., outer periphery 93, is shorter than H1.

[0054] When the curves that are convex toward the +Y and −Y directions in the outline of the above-mentioned figure along which the first end 81 follows are approximately arcs, the radius R1 of the arcs can be determined arbitrarily. R1 is, for example, preferably at least 1 / 2 and not more than 10 times W1, and more preferably at least 3 / 4 and not more than 5 times W1. When R1 is within the former range, good electrical connection between the IC module 7 and the antenna 8 is achieved, material consumption of the antenna wire 83 is reduced, and the embedding process into the card base 2 is made more efficient. When R1 is within the latter range, changes in electrical connection due to relative positional misalignment between the IC module 7 and the antenna 8 are minimized, and further material reduction and embedding speed of the antenna wire 83 are achieved.

[0055] The IC module 7 typically has a contour shape of a substantially rectangle with rounded corners in a plan view. In this case, the contour shape of the recess 9 is also substantially the same as the contour shape of the IC module 7, and more specifically, in consideration of the accuracy of the mounting position of the IC module 7 on the card body 2, the contour shape is often made larger than the contour shape of the IC module 7 by approximately 0.1 mm to 0.2 mm. In this case, the outer periphery 93 of the recess 9 is a substantially rectangle with sides substantially parallel to the short and long sides of the card body 2, and the first end 81 and the second end 82 are formed by a structure in which the antenna wire 83 is repeatedly folded back from the outer periphery 93, which is the side of the recess 9 substantially parallel to the short sides of the card body 2, toward the center.

[0056] On the other hand, if the contour shape of the IC module 7 and recess 9 is an ellipse or the like, the straight line along the side of the outer periphery 93 of the recess 9 indicates a tangent to the center of the side, since the side is a curve such as an arc. Usually, the contour of the IC module 7 is configured to be symmetrical in the vertical and horizontal directions, so if the first end 81 and the second end 82 are formed in the horizontal direction, the straight line along the side of the outer periphery 93 of the recess 9 will be a straight line parallel to the Y axis.

[0057] Furthermore, the zigzag arrangement pitch p1 of the antenna wires 83 at the first end 81 depends on factors such as the capacity of the winding machine and the quality of the antenna sheet 12 after the antenna wires 83 are embedded in the core layer 5, but is preferably 0.50 mm or less, and more preferably 0.25 mm or less. When the pitch p1 is in the former range, the exposed area of the antenna wires 83 per unit area at the first end 81 can be increased, and the area for electrical connection with the terminals 73a of the IC module 7 can be expanded. This improves the reliability of the electrical connection and reduces the electrical resistance at the contact points between the antenna wires 83 and the terminals 73a. When the pitch p1 is in the latter range, the above-mentioned effects can be further enhanced.

[0058] In this embodiment, of the region of first end 81 along the X direction, the end on the +X direction side is substantially coincident with the boundary between first recess 91 and second recess 92, and the end on the −X direction side is located closer to the −X direction than the end of first recess 91, which is the outer periphery 93 of recess 9. In this way, when the end on the +X direction side of first end 81 is substantially coincident with the boundary between first recess 91 and second recess 92 or is located closer to the −X direction than this, it is possible to not cut antenna wire 83 when cutting second recess 92, or to reduce the amount of cutting of antenna wire 83. This makes it possible to suppress branching of antenna wire 83, i.e., the occurrence of whiskers, which are more likely to occur as the cutting depth increases.

[0059] Furthermore, the end of the first end 81 along the X direction on the -X direction side is located closer to the -X direction than the end of the first recess 91, which is the outer periphery 93 of the recess 9. This ensures that the densely packed area of the antenna wires 83 remains uninterrupted even if the antenna 8 is misaligned with respect to the core layer 5 or the recess 9 is misaligned. This ensures a reliable electrical connection with the terminal 73a of the IC module 7. However, the end of the first end 81 along the X direction on the +X direction side may be located closer to the +X direction than the boundary between the first recess 91 and the second recess 92, or the end of the -X direction side may be located closer to the +X direction than the end of the first recess 91, which is the outer periphery 93 of the recess 9.

[0060] The above description is about the relationship between the first end 81 of the antenna 8 and the terminal 73a of the IC module 7 that is electrically connected thereto, but the same relationship also holds between the second end 82 and the terminal 73b that is electrically connected thereto. Also, in this embodiment, the description is based on the premise that the antenna 8 has two ends, the first end 81 and the second end 82, for electrically connecting with the IC module 7, but the antenna 8 may have three or more ends, and the IC module 7 may have the same number of corresponding terminals.

[0061] (b) IC module Next, each of the main components of the IC module 7 will be described mainly with reference to FIGS. 2(b) and 4. FIG. 4(a) is a view of the external connection terminal 71 side of the IC module 7 from the +Z direction, similar to FIG. 1(a). FIG. 4(b) is a view of the IC module 7 from the -Z direction, opposite to FIG. 4(a). Most of the molded portion 74b of the IC chip body 74 is omitted here to allow a see-through view of the interior. FIG. 4(c) is an enlarged cross-sectional view of portion B near the terminal 73a in FIG. 2(b).

[0062] The IC module 7 is embedded in a recess 9 formed in the card base 2, and terminals 73a and 73b of the IC module 7 are electrically connected to a first end 81 and a second end 82 of the antenna 8, respectively, thereby forming a communication circuit for contactless communication. At this time, contact communication with a contact-type reader / writer or the like can be performed through the external connection terminal 71 provided on the IC module 7.

[0063] Substrate 72 is formed by bonding copper foil to the front and back of a flexible resin film, such as glass epoxy resin or polyimide resin, with an adhesive, and leaving the copper foil on the front and back of the resin film so as to form a predetermined pattern. Specifically, a photosensitive material is applied, a film plate with a predetermined pattern is placed, exposed, and the non-photosensitive portion is etched away to form external connection terminal 71 on one copper foil surface of the resin film and terminals 73a and 73b on the other copper foil surface. This sequential process forms substrate 72, with copper foil remaining in the predetermined pattern on the front and back of the resin film. Substrate 72 also has a plurality of bonding holes 76, which are through-holes for wire bonding to external connection terminal 71, pre-formed in the substrate.

[0064] As shown in Fig. 4(a), the external connection terminal 71 has sections defined for the external terminal as defined by the ISO / IEC 7816-2 standard. As shown in Fig. 4(b), these sections are connected to the IC chip 74a by wires 75 such as gold wires through the bonding holes 76 provided in the substrate 72. Similarly, the terminals 73a and 73b are connected to the IC chip 74a by wires 75. These bonding holes 76 and wires 75 are covered and protected by the molded portion 74b.

[0065] An IC chip body 74 is disposed on the surface of the substrate 72 opposite to the surface on which the external connection terminals 71 are formed. The IC chip body 74 is composed of an IC chip 74a adhered and fixed to the substrate 72 with an adhesive, bonding wires 75 for connection, and a molded portion 74b made of sealing resin for protecting these. The IC chip 74a includes a CPU for controlling both contact and contactless communication operations, storage devices such as RAM, ROM, EEPROM, and flash memory, and various circuits such as an interface circuit for decoding input signals and generating output signals for contact and contactless communication, and a power generation circuit. Note that these various circuits may be provided as elements separate from the IC chip 74a.

[0066] The molded portion 74b is provided as a protruding portion that covers the IC chip 74a and the wires 75 to protect them from external force loads and environmental loads. The molded portion 74b is made of an ultraviolet curable resin, a thermosetting resin, or the like.

[0067] (c) Conductive adhesive layer After forming a recess 9 for embedding the IC module 7 in the card base 2 by cutting using an end mill or the like, the conductive adhesive layer 11 is described below, which embeds and fixes the IC module 7 in the recess 9 and electrically and mechanically connects it to the recess 9. As shown in Fig. 4(c), the conductive adhesive layer 11 is a liquid or tape-like member that is disposed so as to be sandwiched between the core layer 5 in the portion where the antenna wire 83 is partially cut away and exposed on the bottom surface 91a, the substrate 72 of the IC module 7, and the terminal 73a formed on the substrate 72.

[0068] The conductive adhesive layer 11 may be applied or attached in advance to the surface of the substrate 72 of the IC module 7 opposite the external connection terminal 71, or may be applied or attached to the bottom surface 91a of the recess 9 of the card base 2 after cutting.

[0069] A typical conductive adhesive layer 11 also serves as a mechanical connection between the IC module 7 and the cut card base 2, and may be applied or attached to the entire back surface of the substrate 72 or to a portion of the recess 9 that corresponds to the first recess 91. In this way, the same type of conductive adhesive layer 11 can be used to electrically connect the IC chip 74a and the antenna 8 and to mechanically connect the IC module 7 and the card base 2, which contributes to simplification of the process.

[0070] However, the conductive adhesive layer 11 may be applied and stuck to the rear surface of the substrate 72 so as to cover only the areas of the terminals 73a and 73b, and another adhesive that is not conductive may be applied and stuck to the rest of the rear surface of the substrate 72. This is because the other adhesive does not need to be considered in terms of conductivity, making it easier to select an adhesive that is more advantageous for mechanical connection.

[0071] The conductive adhesive layer 11, which can be used for both electrical and mechanical connection, can be anisotropically conductive film (ACF) or anisotropically conductive paste (ACP). Other materials that can be used include conductive pastes, such as epoxy resin with silver particles dispersed as a filler. When using ACF, the ACF can be thermally laminated over the entire back surface of the substrate 72 of the IC module 7, and the IC module 7 can then be embedded in the recess 9 of the card base 2 after being cut. This allows for heat pressing at a predetermined temperature and load. This facilitates electrical connection between the IC chip 74a and the antenna 8. Furthermore, the mechanical connection of the IC module 7 to the card base 2 can be simultaneously achieved, simplifying the process of mounting the IC module 7 on the card base 2.

[0072] The electrical connection between the IC chip 74a and the antenna 8 and the mechanical connection between the IC module 7 and the card base 2 when an ACF is used as the conductive adhesive layer 11 can be explained as follows, based on Figure 4(c). The conductive adhesive layer 11 has a configuration in which conductive particles 11a, each consisting of spherical resin or metal spheres surrounded by a metal film, are dispersed in an adhesive 11b, which is a binder containing an adhesive component. Here, thermal pressure is applied to the substrate 72 from the +Z direction to the -Z direction so that the conductive adhesive layer 11, which is arranged so as to be sandwiched between the core layer 5 from which a portion of the antenna wire 83 is exposed, the substrate 72 of the IC module 7, and the terminals 73a formed on the substrate 72, is compressed.

[0073] As a result, strong thermal pressure is applied to the area of the conductive adhesive layer 11 that is particularly narrow and is sandwiched between the core layer 5 and the terminal 73a, and the conductive particles 11a of the conductive adhesive layer 11 in this area are pressed against the exposed antenna wire 83 of the core layer 5 and the terminal 73a along the thickness direction of the conductive adhesive layer 11. Furthermore, if the conductive particles 11a are small, the conductive particles 11a overlap in a daisy chain manner from the antenna wire 83 to the terminal 73a along the thickness direction of the conductive adhesive layer 11. In other words, the exposed antenna wire 83 and the terminal 73a are electrically connected via the conductive particles 11a.

[0074] On the other hand, between the core layer 5 and the substrate 72 in the region where the terminals 73a are not present, the conductive particles 11a are not compressed to the extent that they are pressed against the antenna wire 83 and the terminals 73a along the thickness direction of the conductive adhesive layer 11, or to the extent that they overlap in a daisy chain fashion. However, the adhesive force of the adhesive 11b generated by the thermal pressure mechanically connects the core layer 5 and the substrate 72.

[0075] (d) Manufacturing method of dual interface card 1 Next, an example of a method for manufacturing the dual interface card 1 using the card base 2, IC module 7, and conductive adhesive layer 11 described above will be described.

[0076] First, a coated conductor wire coated with an insulating member is embedded as an antenna wire 83 using a winding former, starting from either the first end 81 or the second end 82 and ending at the other, on the surface of either the core layer 5 or 4 on the side not adjacent to the over-sheet layer 6 or 3. Specifically, for example, while applying a predetermined heat and pressure to the core layer 5, an antenna supply head is drawn into a loop shape as shown in FIG. 1(a), and the antenna wire 83 supplied from the antenna supply head is successively embedded in the core layer 5.

[0077] Here, antenna wire 83 is arranged at predetermined positions on the left and right of the intended mounting position of IC module 7 so that first end 81 and second end 82 are aligned in the left-right direction, and antenna wire 83 is cut at its end point. The movement of the winding machine is changed to adjust the arrangement position of antenna wire 83 so that first end 81 and second end 82 are formed by the antenna wire 83 constituting antenna 8 having a repeated folded structure extending from the outer periphery 93 toward the center of recess 9. Here, antenna 8 is formed by being embedded in core layer 5 so that the portion of antenna wire 83 other than the bent portion of the folded structure is aligned along the Y-axis, which is a straight line along the outer periphery 93.

[0078] Furthermore, antenna 8 is embedded in core layer 5 so that first end 81 and second end 82 follow the contour of a shape that expands convexly toward each other in a direction perpendicular to the direction from the outer periphery 93 toward the center of recess 9. That is, antenna 8 is embedded in core layer 5 so that first end 81 and second end 82 follow the contour of a figure surrounded by approximately arc-shaped curves that are convex toward each of the +Y direction side and the −Y direction side, and approximately straight line segments along the Y axis on each of the −X direction side and the +X direction side.

[0079] Next, as shown in Figure 2, over-sheet layer 6, core layer 5, core layer 4, and over-sheet layer 3 are stacked in this order from the bottom in the thickness direction. After that, each large-sized sheet laminate with cards arranged vertically and horizontally in multiple faces is sandwiched between stainless steel plates from above and below in the thickness direction, and heat and pressure are applied to the laminate via the stainless steel plates. At this time, an antenna 8 has already been formed on core layer 5.

[0080] By undergoing such a heat pressing process, a card base consisting of large sheets in which the layers of the laminate are integrated can be obtained. If either the oversheet layer or the core layer has heat resistance such that they do not heat-seal at a predetermined temperature, an adhesive sheet that heat-seals at a predetermined temperature can be sandwiched between the layers, or an adhesive can be applied, and then the resulting mixture can be subjected to the heat pressing process to obtain a card base consisting of large sheets in which the layers are integrated.

[0081] The large-sized card substrate obtained as described above, on which cards are arranged in a multi-faced array, is punched out by a punching machine into card substrates 2 that meet the ISO / IEC 7816 card size. In addition, recesses 9 for embedding IC modules 7 are formed in the card substrate 2 by cutting using an end mill. This results in the cut card substrate 2. As described above, the recesses 9 are made up of two stages: a first recess 91 for accommodating the flat substrate 72 of the IC module 7, and a second recess 92 for accommodating the convex IC chip body 74.

[0082] Here, the depth of the first recess 91 is associated with the embedding depths of the first end 81 and the second end 82 of the antenna 8. That is, when the first recess 91 is formed by cutting, a part of the antenna wire 83 of the first end 81 and the second end 82 is exposed on the bottom surface 91a of the first recess 91. In other words, the depth from the surface on the exposed side of the external connection terminal 71 of the card substrate 2 to the bottom surface 91a of the first recess 91 is d1, the distance from the surface to the upper end of the antenna wire 83 of either the first end 81 or the second end 82 is d2, and the distance from the surface to the lower end of the one antenna wire 83 is d3. At this time, for the values of d1, d2, and d3, d2 < d1 < d3 holds. This is because if this is not satisfied, the antenna wire 83 will be disconnected or will not be exposed from the bottom surface 91a due to the cutting process.

[0083] Also, the recess 9 is formed such that the surface of the external connection terminal 71 is substantially flush with the surface of the non-cut area of the card substrate 2. Here, the thickness of the substrate 72 of the IC module 7 is about 0.07 mm or more and 0.2 mm or less, the thickness of the IC chip body 74 is about 0.45 mm or more and 0.75 mm or less, and the thickness of the conductive adhesive layer 11 is usually about 0.03 mm or more and 0.2 mm or less. Considering these, the depth of the first recess 91 is usually about 0.1 mm or more and 0.4 mm or less, and the depth of the second recess 92 is usually about 0.48 mm or more and 0.78 mm or less. Note that the depth of the second recess 92 is deeper than the depth of the first recess 91.

[0084] On the other hand, separately from the manufacturing of the card substrate 2 and the cutting process for forming the recess 9, the conductive adhesive layer 11 is attached to the IC module 7. As the IC module 7, usually, a module tape in which the IC module 7 is continuously formed in a single row or two rows on a long tape is used. An ACF in tape form is pasted onto the surface of the module tape opposite to the surface on which the external connection terminals 71 are formed while applying a certain thermal pressure. Then, the module tape with the ACF pasted thereon is punched out with a punching machine as a substantially rectangular IC module 7 having rounded corners to obtain the IC module 7 with the conductive adhesive layer 11 attached.

[0085] Thereafter, the IC module 7 with the conductive adhesive layer 11 attached is embedded in the card base 2 with the recess 9 formed therein, and a predetermined heat block is pressed against the external connection terminal 71 to apply a predetermined heat pressure toward the card base 2 for a predetermined time. This melts the conductive adhesive layer 11 made of ACF, thereby establishing electrical connections between the terminals 73a and 73b of the IC module 7 and the first end 81 and second end 82 of the antenna 8, as well as mechanical connections between the IC module 7 and the card base 2. The application time and heat pressure conditions vary depending on the type and composition of the ACF, but an example is a time of 0.5 seconds to 10.0 seconds, a temperature of 150°C to 250°C, and a pressure of 20 MPa to 100 MPa.

[0086] (e) Dual Interface Card of the First Embodiment In summary, the dual interface card 1 of the first embodiment includes a card base 2 and an antenna 8 disposed inside the card base 2 and having at least a plurality of ends, namely, a first end 81 and a second end 82. The dual interface card 1 further includes an IC module 7 having an IC chip 74a and a plurality of terminals 73a and 73b electrically connected to the IC chip 74a. The IC module 7 is disposed in a recess 9 provided in the card base 2 so that the plurality of terminals 73a and 73b facing each other and the plurality of first ends 81 and second ends 82 are electrically connected to each other.

[0087] The first end 81 and the second end 82, which are the multiple end portions, are configured by an antenna wire 83 that constitutes the antenna 8, with a repeated folding structure that extends from the outer periphery 93 of the recess 9 toward the center, and a part of the structure is exposed to the recess 9. Furthermore, the portion of the folded structure of the antenna 8 other than the bent portion is along a straight line that follows the sides 93a and 93b of the outer periphery 93, and the multiple first end portions 81 and second end portions 82 are formed so as to follow the outline of a predetermined shape.

[0088] The predetermined shape is a graphic shape in which the first end 81 and the second end 82 in the range from the outer periphery 93 toward the center of the recess 9 expand convexly toward both the +Y direction and the −Y direction along a direction perpendicular to the direction from the outer periphery 93 toward the center of the recess 9. In addition, the first exposed portion 84 and the second exposed portion 85 of the first end 81 and the second end 82, which are portions of the antenna wire 83 exposed from the recess 9, also form part of the above-mentioned predetermined shape.

[0089] Therefore, in the dual interface card 1 of this embodiment, the first end 81 and the second end 82 can be formed relatively compactly while reducing the amount of antenna wire 83 used, which allows for efficient embedding of the antenna wire 83 in the substrate while applying heat and pressure. Furthermore, the length along the Y axis of the portion of the antenna wire 83 constituting the first end 81 and the second end 82 other than the bent portion of the folded structure can be arranged to be relatively long near the area where it overlaps with the terminals 73a and 73b of the IC module 7, and relatively short near the area where it does not overlap.

[0090] Furthermore, the amount of cutting of antenna wire 83 can be reduced during cutting using an end mill, thereby preventing unintended branching of antenna wire 83. As a result, in the dual interface card 1 of this embodiment, antenna 8 can be formed efficiently and at low cost while ensuring the reliability of the electrical connection between IC module 7 and antenna 8 and the adhesion of IC module 7 to card base 2.

[0091] 2. Second embodiment Next, a dual interface card according to a second embodiment of the present disclosure will be described.

[0092] 5 is a diagram illustrating the configuration of a first end 81a of an antenna 8 of a dual interface card according to a second embodiment, corresponding to FIG. 3. The first end 81a of the dual interface card according to this embodiment follows a different outline than the first end 81 of the first embodiment. The entire first end 81a has a maximum width H1 along the Y axis and a width W1 along the X axis. The antenna wire 83 is arranged so that the width along the Y axis of the first end 81a is maximum width H1 at the portion overlapping with the terminal 73a of the IC module 7, as indicated by the dashed dotted line in FIG. 5, and the width along the Y axis of the portion other than the overlapping portion is smaller than maximum width H1.

[0093] The portion of first end 81a on the -X direction side that overlaps with approximately half of terminal 73a on the -X direction side is referred to as first portion AR11, and the portion of first end 81a on the +X direction side of first portion AR11 that overlaps with approximately half of terminal 73a on the +X direction side is referred to as second portion AR12. In this case, first portion AR11 is formed so that the width of first end 81a along the Y axis gradually increases along a linear contour on both the +Y direction and the -Y direction as it progresses from the -X direction to the +X direction. Meanwhile, second portion AR12 is formed so that the width of first end 81a along the Y axis gradually decreases along a substantially arc-shaped contour on both the +Y direction and the -Y direction as it progresses from the -X direction to the +X direction.

[0094] Terminal 73a is positioned closer to the +X direction than approximately the center of first end 81a in the direction along the X axis. Therefore, first portion AR11 has a greater width along the X axis than second portion AR12, and the figure along which first end 81a extends is approximately line-symmetric when viewed along the Y axis direction but asymmetric when viewed along the X axis direction. As described above, the figure along which first end 81a extends is surrounded by a portion where approximately straight line segments and approximately arc-shaped curves that are convex toward each of the +Y direction and the -Y direction are joined, and approximately straight line segments along the Y axis on each of the -X direction and the +X direction.

[0095] However, the shape along which first end 81a follows is not limited to this, and first portion AR11 may be formed so that the width of first end 81a along the Y axis gradually increases along a substantially arc-shaped contour on each of the +Y direction side and the -Y direction side as it progresses from the -X direction side to the +X direction side. Furthermore, second portion AR12 may be formed so that the width of first end 81a along the Y axis gradually decreases along a substantially linear contour on each of the +Y direction side and the -Y direction side as it progresses from the -X direction side to the +X direction side.

[0096] Furthermore, a third portion AR13 may be provided between the first portion AR11 and the second portion AR12, overlapping with approximately the center portion of the terminal 73a, and in the third portion AR13, the width of the first end 81a in the direction along the Y axis may be formed to maintain approximately the same maximum width H1 as it progresses from the -X direction side to the +X direction side.

[0097] The above description applies to the first end 81a, but it also applies to the second end arranged next to it on the +X direction side. In this case, it is preferable that the second end is formed symmetrically with the first end 81a, that is, line-symmetrically with respect to a line along the Y axis. However, the second end may not be symmetrical with the first end 81a, but may be formed as a shape obtained by translating the first end 81a along the XY plane. This point is also common to the following embodiments.

[0098] In this way, the antenna wire 83 is arranged so that the width along the Y axis of the first end 81a is maximum width H1 at the portion where it overlaps with the terminal 73a of the IC module 7, and the width along the Y axis of the portion other than this overlapping portion is smaller than maximum width H1. This provides the following effect: Since the length of the antenna wire 83 along the Y axis at the portion where it overlaps with the terminal 73a is relatively long, good electrical connection between the IC module 7 and the antenna 8 can be achieved.

[0099] Furthermore, in the second portion AR12, the shape along which the antenna wire 83 extends can be made substantially trapezoidal and does not include a substantially circular arc, so that the length of the antenna wire 83 along the Y axis in the portion that does not overlap with the terminal 73a can be further shortened. This makes it possible to further reduce the amount of antenna wire 83 used and further improve the efficiency of the work of embedding the antenna wire 83. Furthermore, it is possible to prevent unintended branching of the antenna wire 83 during cutting.

[0100] 3. Third embodiment Next, a dual interface card according to a third embodiment of the present disclosure will be described.

[0101] FIG. 6 is a diagram illustrating the configuration of a first end 81b of an antenna 8 of a dual interface card according to a third embodiment, corresponding to FIG. 3. The first end 81b of the dual interface card according to this embodiment follows a different outline than the first end of each of the previously described embodiments. The entire first end 81b has a maximum width H21 along the Y axis and a width W1 along the X axis. The antenna wire 83 is arranged such that the width along the Y axis of the first end 81b is maximum width H21 at the portion overlapping with the terminal 73a of the IC module 7, as indicated by the dashed dotted line in FIG. 6, and the width along the Y axis of the portion other than the overlapping portion is smaller than maximum width H21.

[0102] The portion of first end 81b on the -X direction side that does not overlap with terminal 73a is designated as first portion AR21, and the portion of first end 81b on the +X direction side of first portion AR21 that overlaps with terminal 73a is designated as second portion AR22. The portion of first end 81b on the +X direction side of second portion AR22 that does not overlap with terminal 73a is designated as third portion AR23. In this case, in first portion AR21 and third portion AR23, first end 81b has a substantially constant width H22 in the direction along the Y axis, and the value of H22 is smaller than the value of H21. Meanwhile, in second portion AR22, first end 81b has a substantially constant maximum width H21 in the direction along the Y axis.

[0103] As a result, the shape along which the first end 81b extends is a shape obtained by combining the first approximately rectangular portion constituting the first portion AR21, the second approximately rectangular portion constituting the second portion AR22, and the third approximately rectangular portion constituting the third portion AR23. Here, the second approximately rectangular portion has a width along the Y axis greater than the first approximately rectangular portion and the third approximately rectangular portion, so the shape along which the first end 81b extends is a substantially cross shape. However, the widths along the Y axis of the first portion AR21 and the third portion AR23 do not need to be the same, and may be different widths that are shorter than H21.

[0104] Meanwhile, the figure along which the first end 81b extends may be such that the figure constituting the first portion AR21 is not a first substantially rectangular portion but is a substantially trapezoidal portion having a side facing the second portion AR22 as a lower base with a width H21 and a side facing the -X direction as an upper base narrower than H21. Similarly, the figure constituting the third portion AR23 is not a third substantially rectangular portion but is a substantially trapezoidal portion having a side facing the second portion AR22 as a lower base with a width H21 and a side facing the +X direction as an upper base narrower than H21.

[0105] That is, the shape along which the first end 81b extends may be a substantially octagon. By forming the first end 81b in this shape, even if the position of the terminal 73a in the direction along the X-axis deviates from the range of the second portion AR22, the area of the first end 81b overlapping with the terminal 73a can be smoothly prevented from decreasing. Therefore, good electrical connection between the IC module 7 and the antenna 8 can be achieved while suppressing the effects of misalignment of the IC module 7.

[0106] The width of the second portion AR22 along the X-axis is preferably set slightly wider than the width of the terminal 73a along the X-axis, taking into consideration misalignment of the IC module 7. If the width of the second portion AR22 along the X-axis is Dar22 and the width of the terminal 73a along the X-axis is D73a, then Dar22 is preferably set to 101% or more and 300% or less of D73a, and more preferably 110% or more and 200% or less. Setting Dar22 in the latter range in particular ensures a satisfactory electrical connection between the IC module 7 and the antenna 8, even when considering misalignment of the antenna wire 83, misalignment of the removal position of the card base 2, misalignment of the mounting position of the IC module 7, and the like, thereby reducing the amount of antenna wire 83 used and improving the efficiency of the embedding work.

[0107] In this way, the antenna wire 83 is arranged so that the width along the Y axis is a substantially constant width of maximum width H1 in the portion overlapping with the terminal 73a of the IC module 7, and the width along the Y axis is a substantially constant width smaller than maximum width H1 in the portion other than the overlapping portion. This provides the following advantages. Because the length of the antenna wire 83 along the Y axis in the portion overlapping with the terminal 73a is long and constant, good electrical connection between the IC module 7 and the antenna 8 can be achieved without being affected by misalignment of the IC module 7 mounting position, etc. Furthermore, because the length of the antenna wire 83 along the Y axis in the portion not overlapping with the terminal 73a is short and constant, the amount of antenna wire 83 used can be further reduced, and the embedding process of the antenna wire 83 can be more efficient. Furthermore, unintended branching of the antenna wire 83 during cutting can be suppressed.

[0108] 4. Fourth embodiment Next, a dual interface card according to a fourth embodiment of the present disclosure will be described.

[0109] 7 is a diagram showing the configuration of first end 81c of antenna 8 of a dual interface card of the fourth embodiment, corresponding to FIG. 3. First end 81c of the dual interface card of this embodiment follows the same outline as first end 81 of the first embodiment. That is, the outline has approximately arc-shaped curves that are convex toward both the +Y and −Y directions, and approximately straight line segments along the Y axis on both the −X and +X directions. However, first end 81c differs from first end 81 of the first embodiment in that the arrangement pitch of the antenna wire 83 of first end 81c, other than the bent portions of the adjacent folded structure, varies depending on the region of first end 81c.

[0110] 7, the portion of first end 81c on the -X direction side that does not overlap with terminal 73a is designated as first portion AR31, and the portion of first end 81c on the +X direction side of first portion AR31 that overlaps with terminal 73a is designated as second portion AR32. Furthermore, the portion of first end 81c on the +X direction side of second portion AR32 that does not overlap with terminal 73a is designated as third portion AR33. In this case, in first portion AR31, the arrangement pitch of portions of antenna wire 83 constituting first end 81c other than adjacent bent portions of the folded structure is approximately constant p31, in second portion AR32, the same arrangement pitch is approximately constant p32, and in third portion AR33, the same arrangement pitch is approximately constant p33.

[0111] Here, the value of p32 is smaller than the values of p31 and p33. Typically, the values of p31 and p33 are the same, but they may be different from each other. In other words, the arrangement pitch of the portion of first end 81c other than the bent portion of the folded structure of antenna wire 83 that overlaps with terminal 73a is narrower than the arrangement pitch of the other portion that does not overlap with terminal 73a.

[0112] In this way, in the portion where the first end 81c overlaps the terminal 73a of the IC module 7, the arrangement pitch of the portion other than the bent portion of the folded structure of the antenna wire 83 is narrower than in other portions, thereby increasing the contact area for the electrical connection between the IC module 7 and the antenna 8. This allows for even better electrical connection between the IC module 7 and the antenna 8. Furthermore, because the arrangement pitch is wider in the portion that does not overlap with the terminal 73a, the amount of antenna wire 83 used is further reduced, and the embedding work of the antenna wire 83 is made more efficient. Furthermore, unintended branching of the antenna wire 83 during cutting can be suppressed.

[0113] 5. Fifth embodiment Next, a dual interface card according to a fifth embodiment of the present disclosure will be described.

[0114] FIG. 8 is a diagram illustrating the configuration of a first end 81d of an antenna 8 of a dual interface card according to a fifth embodiment, corresponding to FIG. 3. The first end 81d of the dual interface card according to this embodiment follows the same contour as the first end 81 of the first embodiment. That is, the contour has a substantially arc-shaped curve that is convex toward both the +Y and −Y directions, and has substantially straight line segments along the Y axis on both the −X and +X directions. However, unlike the first end 81 of the first embodiment, the portion of the antenna wire 83 other than the bent portion of the folded structure is tilted clockwise by a predetermined angle θ with respect to a line along the side 93a of the outer periphery 93 of the recess 9 in FIG. 1(b), i.e., a line m1 that is parallel to the Y axis.

[0115] Here, the entire first end 81c is arranged along the outline of a rectangle having a width H1 along the Y axis and a width W1 along the X axis. That is, the length of the portion other than the bent portion of the folded structure is approximately the same near the approximate center of first end 81d in the X direction. However, near the end on the -X direction side and the end on the +X direction side, the length of the portion other than the bent portion of the folded structure gradually decreases toward the -X direction and the +X direction, respectively.

[0116] The inclination angle θ is preferably 2 degrees or more and 20 degrees or less, and more preferably 5 degrees or more and 15 degrees or less. The inclination angle θ does not need to be strictly the same in all portions of the folded structure other than the bent portions, and may vary within the above-mentioned range. When the inclination angle θ is in the former range, the antenna wire 83 is inclined relative to the direction along the Y-axis, which is the movement direction of the end mill when cutting the recess 9, thereby further suppressing unintended branching of the antenna wire 83.

[0117] Furthermore, if the end of first end 81c on the +X direction side is located closer to the +X direction than the boundary between first recess 91 and second recess 92, antenna wire 83 will be cut when second recess 92 is cut, and will break midway. However, if inclination angle θ is within the former range, the region where antenna wire 83 will break can be reduced, and a reliable electrical connection can be achieved between antenna 8 and terminal 73a of IC module 7.

[0118] On the other hand, by setting the inclination angle θ in the latter range, it is possible to effectively suppress the occurrence of whiskers, which are branches of the antenna wire 83. Furthermore, even if the end on the +X direction side of the first end portion 81 is located on the +X direction side of the boundary between the first recess 91 and the second recess 92, it is possible to further reduce the region of disconnection of the antenna wire 83 due to cutting of the antenna wire 83 when cutting the second recess 92. As a result, it is possible to further improve the reliability of the electrical connection between the antenna 8 and the terminal 73a of the IC module 7.

[0119] In particular, when the end on the +X direction side is located on the +X direction side of the boundary between the first recess 91 and the second recess 92, it is preferable to arrange the antenna wire 83 in this region so that it includes the bent portion of the folded structure but does not include any portion other than the bent portion. By doing so, when cutting the second recess 92, it is less likely that the antenna wire 83 will branch from the bent portion that is at a large angle from the direction along the Y axis, which is the movement direction of the end mill, and this ultimately contributes to improved quality.

[0120] In this embodiment, the inclination angle θ is the angle at which the portion other than the bent portion is inclined clockwise with respect to the straight line m1. However, there is no problem in replacing the above-mentioned θ with the angle at which the portion other than the bent portion is inclined counterclockwise with respect to the straight line m1. This is because even if the portion other than the bent portion is inclined counterclockwise, the same effect as when it is inclined clockwise can be obtained.

[0121] As described above, the embodiments and modifications described in this disclosure can be combined in part or in whole to the extent that no contradictions arise, and such combinations are naturally included in this disclosure. For example, in the first end 81b of the third embodiment, the contour shapes of the first portion AR21, the second portion AR22, and the third portion AR23 may be parallelograms, and the portion of the antenna wire 83 other than the bent portion of the folded structure may be inclined by an angle θ with respect to the straight line m1, as in the first end 81d of the fifth embodiment.

[0122] Furthermore, in the first end 81a of the second embodiment, the first end 81b of the third embodiment, or the first end 81d of the fifth embodiment, the antenna wire 83 overlapping with the terminal 73a of the IC module 7 may be configured as follows. That is, the antenna wire 83 may be arranged with a narrower arrangement pitch in the portion other than the bent portion of the folded structure than in the other portions, as in the first end 81c of the fourth embodiment. This is because, even when the embodiments and modified examples are combined in this way, the same effects of the respective embodiments and modified examples can be obtained. [Explanation of symbols]

[0123] 1 Dual Interface Card 2 Card Base 3, 6 oversheet layers 4, 5 Core layer 7 IC modules 8 Antennas 9 Recess 11 Conductive adhesive layer 11a Conductive particles 11b Adhesive 71 External connection terminal 72 PCB 73a, 73b terminal 74 IC chip body 74a IC chip 74b molded part 74p Pad 75 wire 76 Bonding Hole 81, 81b, 81c, 81d First end 81p, 81q antenna end 82, 82b 2nd end 83 Antenna Wire 84 1st exposed part 85 2nd exposed part 91 First recess 91a bottom 92 Second recess 93 Outer circumference Areas 93a and 93b

Claims

1. A dual interface card capable of contact communication and contactless communication with an external device, A card base; an antenna having a plurality of ends disposed within the card base; an IC module having an IC chip and a plurality of terminals electrically connected to the IC chip; the IC module is disposed in a recess provided in the card base so that the plurality of terminals and the plurality of end portions facing each other are electrically connected, the plurality of ends are formed by a structure in which an antenna wire constituting the antenna is repeatedly folded back from the outer periphery toward the center of the recess, and a part of the ends is exposed in the recess; A dual interface card, wherein the multiple ends in the range from the outer periphery toward the center of the recess are formed to follow the contours of shapes that expand convexly toward each other in a direction perpendicular to the direction from the outer periphery toward the center of the recess.

2. 2. The dual interface card of claim 1, wherein the recesses are composed of a first recess formed on the outer periphery and having approximately the same depth, and a second recess formed closer to the center than the first recess and deeper than the first recess.

3. 3. The dual interface card according to claim 1, wherein the plurality of terminals and the plurality of end portions of the IC module that face each other are electrically connected to each other via an anisotropic conductive film.

4. 4. A dual interface card as described in any one of claims 1 to 3, wherein the outer periphery is a substantially rectangular shape having sides substantially parallel to the short and long sides of the card body, and the multiple ends are formed by a repeated folding structure from the outer periphery, which is a side of the recess substantially parallel to the short sides of the card body, toward the center by an antenna wire constituting the antenna.

5. 5. A dual interface card as described in any one of claims 1 to 4, wherein, among the multiple ends in the range from the outer periphery toward the center of the recess, the width of one region that overlaps with the multiple terminals in a direction perpendicular to the direction from the outer periphery toward the center of the recess is larger than the width of another region in a direction perpendicular to the direction from the outer periphery toward the center of the recess.

6. the end portion is composed of a bent portion and a portion other than the bent portion, When a portion of the end portion other than the bent portion that overlaps with the terminal is defined as a first portion, and a portion of the end portion other than the bent portion that does not overlap with the terminal is defined as a second portion, 6. The dual interface card according to claim 1, wherein an arrangement pitch of the antenna wires in the first portion is narrower than an arrangement pitch of the antenna wires in the second portion.

7. The dual interface card according to claim 6 , wherein the portion of the end portion other than the bent portion is inclined relative to a straight line along the outer periphery.

8. 8. The dual interface card according to claim 7, wherein the angle of inclination of any of the terminals relative to a straight line along the outer periphery of a portion other than the bent portion is equal to or greater than 5 degrees and equal to or less than 20 degrees.

9. A method for manufacturing a dual interface card capable of contact communication and contactless communication with an external device, comprising: an antenna forming step of embedding an antenna wire into a first base material while applying heat and pressure to form an antenna having a plurality of ends on one surface of the first base material; a lamination step of laminating a second base material on the first base material on which the antenna is formed so as to sandwich the antenna; a punching step of punching a laminate obtained by stacking the first base material and the second base material into a card-sized card base; a recess forming step of forming a recess in the card base for embedding an IC module; an IC module preparation step of preparing an IC module having an IC chip and a plurality of terminals electrically connected to the IC chip; an IC module bonding step of bonding the IC module to the recess of the card base via a conductive adhesive so that the plurality of terminals and the plurality of end portions facing each other are electrically connected, the plurality of ends are formed by a structure in which an antenna wire constituting the antenna is repeatedly folded back from the outer periphery toward the center of the recess, and a part of the ends is exposed in the recess; A method for manufacturing a dual interface card, wherein the multiple ends in the range from the outer periphery toward the center of the recess are formed to follow the contours of shapes that expand convexly toward each other in a direction perpendicular to the direction from the outer periphery toward the center of the recess.

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