Dual interface IC card, intermediate body, and method for manufacturing dual interface IC card

Abstract

To provide a dual interface IC card or the like capable of suppressing disconnection near the root of a welding part with a conductive plate at an antenna end part when the dual interface IC card is repeatedly bent.SOLUTION: According to an aspect of the present invention, there is provided an IC card including a card body 20 having a recessed portion 20A in a front surface 20C, an IC module 30 disposed in the recessed portion 20C, a conductive plate 40 disposed inside the card body 20 and partially exposed in the recessed portion 20C, and an antenna 50 disposed inside the card body 20, the antenna 50 being disposed between the IC module 30 and an exposed portion 41 of the conductive plate 40 exposed in the recessed portion 20C, and a conductive adhesive layer 60 for electrically connecting the IC module 30 and the conductive plate 40, and the end 51 of the antenna 50 has a welded part 20A welded to a face 40A on the opposite side of a face 40B on the front side 51A side of the card base body 20 in the conductive plate 40.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a dual interface IC card, an intermediate, and a method for manufacturing the dual interface IC card. [Background technology]

[0002] Conventionally, contact IC cards have been used, which communicate with external devices through contact terminals on the surface of the card, contactless IC cards which communicate with external devices through an antenna using electromagnetic induction or the like, and dual interface IC cards which can achieve both the functions of a contact IC card and a contactless IC card using a single IC chip on the card.

[0003] Of these, in a dual interface IC card, an IC module equipped with an IC chip is disposed in a recess provided on the surface of the card base and is electrically connected to an antenna disposed inside the card base.

[0004] However, when a recess for arranging an IC module is formed by cutting, if the end of the antenna is exposed in the recess, there is a risk that the end of the antenna may be broken by cutting.

[0005] For this reason, a part of the end of the antenna is welded to a conductive plate, and a part of the conductive plate is exposed in a recess, so that the conductive plate and the IC module are electrically connected (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-91637 Summary of the Invention [Problem to be solved by the invention]

[0007] However, if a portion of the antenna end is welded to a conductive plate, there is a risk that cracks will occur near the base of the weld between the antenna end and the conductive plate during repeated bending tests of a dual interface IC card, causing the antenna to break.

[0008] The present invention has been made to solve the above problems, and aims to provide a dual interface IC card that can prevent breakage near the base of the weld between the antenna end and the conductive plate when the dual interface IC card is repeatedly bent, an intermediate product used in the manufacture of such a dual interface IC card, and a method for manufacturing such a dual interface IC card. [Means for solving the problem]

[0009] [1] A dual interface IC card capable of contact communication and contactless communication with an external device, comprising: a card base having a recess on its surface; an IC module disposed within the recess; a conductive plate disposed inside the card base and having a portion exposed within the recess; an antenna disposed inside the card base; and a conductive adhesive layer disposed between the IC module and the portion of the conductive plate exposed within the recess, electrically connecting the IC module and the conductive plate, wherein an end of the antenna has a welded portion welded to the surface of the conductive plate opposite to the surface on the front side of the card base.

[0010] [2] A dual interface IC card as described in [1] above, wherein the ratio of the depth from the surface of the card base to the welded portion at the end of the antenna to the conductive plate to the depth from the surface of the card base to the center position of the card base in the thickness direction of the card base is 70% or more and 98% or less.

[0011] [3] A dual interface IC card capable of contact communication and contactless communication with an external device, comprising: a card base having a recess on its surface; an IC module disposed in the recess; a conductive plate disposed inside the card base with a portion exposed in the recess; an antenna disposed inside the card base; and a conductive adhesive layer disposed between the IC module and the portion of the conductive plate exposed in the recess and electrically connecting the IC module and the conductive plate, wherein an end of the antenna has a weld welded to one surface of the conductive plate, and the ratio of the depth from the surface of the card base to the weld in the thickness direction of the card base to the depth from the surface of the card base to the center position of the card base is 70% or more and 98% or less.

[0012] [4] The dual interface IC card according to any one of [1] to [3] above, wherein the conductive adhesive layer is an anisotropic conductive film.

[0013] [5] The dual interface IC card according to any one of [1] to [3] above, wherein the conductive adhesive layer is an anisotropic conductive paste layer.

[0014] [6] The dual interface IC card according to any one of [1] to [5] above, wherein the thickness of the conductive plate is 70 μm or more and 150 μm or less.

[0015] [7] An intermediate used in the manufacture of a dual interface IC card capable of contact and contactless communication with an external device, comprising: a card base having a recessed area on its surface where a recess for placing an IC module is to be formed; a conductive plate disposed inside the card base and electrically connected to the IC module; and an antenna disposed inside the card base, the end of which is welded to the surface of the conductive plate opposite to the surface on the front side of the card base.

[0016] [8] An intermediate used in the manufacture of a dual interface IC card capable of contact and contactless communication with an external device, comprising: a card base having a planned recess area on its surface where a recess for placing an IC module is to be formed; a conductive plate disposed inside the card base and electrically connected to the IC module; and an antenna disposed inside the card base, wherein in the thickness direction of the card base, the ratio of the depth from the surface of the card base to the welded portion at the end of the antenna with the conductive plate to the depth from the surface of the card base to the center position of the card base is 70% or more and 98% or less.

[0017] [9] A method for manufacturing a dual interface IC card capable of contact communication and contactless communication with an external device, comprising the steps of: arranging a conductive plate on one surface of a first substrate; forming an antenna having an end on said surface of the first substrate; welding a part of the end of the antenna to a surface of the conductive plate opposite to the surface facing the first substrate to form a weld; laminating at least the first substrate and the second substrate by thermal fusion or with an adhesive so as to sandwich the antenna and the conductive plate therebetween to form a card base; cutting the card base from the front side of the card base to form a recess and expose a part of the conductive plate in the recess; arranging a conductive adhesive layer on the terminal of an IC module having an IC chip and a terminal electrically connected to the IC chip; and arranging the IC module in the recess so that the terminal and the conductive plate are electrically connected via the conductive adhesive layer, wherein the weld is located on the surface of the conductive plate opposite to the surface facing the front side of the card base.

[0018]

[10] A method for manufacturing a dual interface IC card as described in [9] above, wherein the ratio of the depth from the surface of the card base to the welded portion to the depth from the surface of the card base to the center position of the card base in the thickness direction of the card base is 70% or more and 98% or less. [Effects of the Invention]

[0019] According to one aspect of the present invention, it is possible to provide a dual interface IC card that can suppress breakage near the base of the weld between the antenna end and the conductive plate when the dual interface IC card is repeatedly bent, an intermediate product used in the production of such a dual interface IC card, and a method for producing such a dual interface IC card. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic plan view of a dual interface IC card according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view taken along the line AA in FIG. [Figure 3] FIG. 3 is a plan view of a recess for embedding an IC module. [Figure 4] FIG. 4 is an enlarged view of a part of FIG. [Figure 5] FIG. 5 is a schematic plan view of a multi-faceted intermediate body according to the embodiment. [Figure 6] FIG. 6 is a schematic plan view of each intermediate body according to the embodiment. [Figure 7] FIG. 7 is a cross-sectional view taken along line BB in FIG. [Figure 8] FIG. 8A is a schematic cross-sectional view showing a manufacturing process of a dual-interface IC card according to the embodiment, and FIG. 8B is a schematic plan view showing a manufacturing process of a dual-interface IC card according to the embodiment. [Figure 9] 9A and 9B are schematic diagrams showing the manufacturing process of the dual-interface IC card according to the embodiment. [Figure 10] 10A and 10B are schematic diagrams illustrating a manufacturing process of a dual-interface IC card according to an embodiment. [Figure 11] 11A and 11B are schematic diagrams illustrating the manufacturing of a dual-interface IC card according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] A dual interface IC card according to an embodiment of the present invention and a method for manufacturing the same will now be described with reference to the drawings. FIG. 1 is a schematic plan view of a dual interface IC card according to this embodiment, FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, FIG. 3 is a plan view of a recess for embedding an IC module, and FIG. 4 is an enlarged view of a portion of FIG. 2. FIG. 5 is a schematic plan view of a multi-faceted intermediate body according to this embodiment, FIG. 6 is a schematic plan view of each intermediate body according to this embodiment, and FIG. 7 is a cross-sectional view taken along line BB in FIG. 6. FIG. 8A is a schematic cross-sectional view showing a manufacturing process for a dual interface IC card according to this embodiment, and FIG. 8B is a schematic plan view showing a manufacturing process for a dual interface IC card according to this embodiment. FIGS. 9A to 11B are schematic views showing the manufacturing process for a dual interface IC card according to this embodiment.

[0022] <<<Dual interface IC card>>> The dual interface IC card 10 (hereinafter sometimes simply referred to as "IC card 10") shown in Figures 1 and 2 comprises a card base 20 having a recess 20C on its surface 20A, an IC module 30 arranged in the recess 20C, a pair of conductive plates 40 partially arranged inside the card base 20, and an antenna 50 arranged inside the card base 20, and also comprises a conductive adhesive layer 60 arranged between the IC module 30 and the conductive plate 40 and electrically connecting the IC module 30 and the conductive plate 40.

[0023] A part of the surface 10A of the IC card 10 is made up of the surface 20A of the card base 20. Specifically, the surface 10A is made up of the surface 20A and the surface of the IC module 30.

[0024] <<Card base>> For ease of explanation, an XYZ coordinate system is set for the card base 20. First, the normal direction to the front surface 20A of the card base 20 is defined as the Z axis. The direction from the back surface 20B, which is the opposite side of the card base 20 to the front surface 20A, toward the front surface 20A 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 card base 20 is viewed from the +Z direction, the X axis is a straight line perpendicular to both short sides of card base 20, which has long and short sides described below, and the Z axis, and the direction from one short side closer to recess 20C to the other short side is the +X direction or rightward, and the opposite direction is the -X direction or leftward. Furthermore, the Y axis is an axis perpendicular to the X and Z axes, and the direction from one long side farther from recess 20C to the other long side is the +Y direction or upward, and the opposite direction is the -Y direction or downward.

[0026] The recess 20C is composed of a first recess 20D and a second recess 20E that is connected to the first recess 20D. The second recess 20E is located deeper than the first recess 20D in the depth direction (from the +Z side to the -Z side) from the front surface 20A toward the back surface 20B. The hole diameter of the second recess 20E is smaller than the hole diameter of the first recess 20D. The first recess 20D is a portion that mainly stores the substrate 31 and the like of the IC module 30, and the second recess 20E is a portion that mainly stores the molded portion 35 and the like.

[0027] 2 has a configuration in which an over-sheet layer 21, a core layer 22, an inner layer 23, a core layer 24, a core layer 25, and an over-sheet layer 26 are laminated in this order in the depth direction (-Z direction) from the front surface 20A toward the back surface 20B. For example, a magnetic stripe may be embedded in the surface of the over-sheet layer 21 opposite to the core layer 22, and a printing layer may be provided on the surface of the core layer 22 facing the over-sheet layer 21 or on the surface of the core layer 25 facing the over-sheet layer 26. This enhances the design of the card, and it can be used as a credit card that reads information from a magnetic stripe.

[0028] <Oversheet layer> The over-sheet layers 21, 26 are usually made of the same material as the inner layer 23, and are often made of a transparent material with a thickness of about 0.03 mm to 0.18 mm. From the viewpoint of preventing curling when the laminate is integrated by heat pressing or the like, as described below, it is preferable that the over-sheet layers 21, 26 have the same thickness, but they do not necessarily have to be the same.

[0029] The material of the over-sheet layers 21 and 26 may be any material that is adhesive when heated, but even if the over-sheet layers themselves are not adhesive when heated, the two can be integrated by additionally forming a layer of a known adhesive that generates adhesive force when heated, etc., between the over-sheet layer 21 and the core layer 22 or between the over-sheet layer 26 and the core layer 25.

[0030] <Core layer> Examples of the core layers 22, 24, and 25 include, but are not limited to, plastic sheets. Examples of the plastic sheets that can be used include polyethylene terephthalate (PET), PET-G (terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer), polyvinyl chloride, copolymer polyester, vinyl chloride-vinyl acetate copolymer, polycarbonate, polyamide, polyimide, cellulose diacetate, cellulose triacetate, polystyrene, ABS, polyacrylic ester, polypropylene, polyethylene, polyurethane, and the like, as well as composite films thereof.

[0031] The thickness of the core layers 22, 24, and 25 can be appropriately selected taking into consideration the overall thickness of the IC card 10, and may be, for example, approximately 0.03 mm or more and 0.45 mm or less. In this case, the above thickness of the core layers 22, 24, and 25 refers to the thickness of each of the core layers 22, 24, and 25. The core layers 22, 24, and 25 may have a laminated structure of two or more layers.

[0032] <Inner layer> The inner layer 23 is not particularly limited, but examples thereof include the plastic sheets described in the section on the core layers 22, 24, and 25. The thickness of the inner layer 23 can be appropriately selected taking into consideration the overall thickness of the IC card 10, and may be, for example, approximately 0.03 mm or more and 0.45 mm or less.

[0033] <<ICモジュール> > 2, the IC module 30 includes a flat substrate 31, external connection terminals 32 arranged on a front surface 31A of the substrate 31, terminals 33 arranged on a rear surface 31B of the substrate 31, an IC chip 34 arranged on the rear surface 31B of the substrate 31, a molded portion 35 that covers the IC chip 34, and wires 36 such as gold wires that electrically connect the terminals 33 and the IC chip 34. Note that the wires that electrically connect the external connection terminals 32 and the IC chip 34 are not shown in the figure.

[0034] <Board, external connection terminals, and terminals> The substrate 31 can be made of a flexible resin film such as glass epoxy resin or polyimide resin. The external connection terminals 32 and terminals 33 are made of patterned copper foil. Specifically, copper foil is provided on the front surface 31A and back surface 31B of the substrate 31, and the copper foil is etched into a predetermined pattern to form the external connection terminals 32 and terminals 33. The substrate 31 is also provided with a plurality of through holes (not shown) in advance for wire bonding to the external connection terminals 32.

[0035] <ICチップ> The IC chip 34 is fixed via an adhesive (not shown) to the rear surface 31B of the substrate 31. Specifically, it is disposed in the center of the surface of the substrate 31 where the terminals 33 are formed. The IC chip 34 includes a CPU for controlling both contact and contactless communication operations, a storage device such as RAM, 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.

[0036] <Molded part> The molded portion 35 is intended to protect the IC chip 34 and the wires 36 from external force loads and environmental loads. The molded portion 35 is made of an ultraviolet curable resin, a thermosetting resin, or the like.

[0037] <<Conductive plate>> The conductive plate 40 is a plate-like member having electrical conductivity. A portion of the conductive plate 40 is exposed in the recess 20C, specifically in the first recess 20D. That is, as shown in FIG. 3 , the conductive plate 40 has an exposed portion 41 exposed in the first recess 20D and a non-exposed portion 42 located within the card base 20. The conductive plate 40 is electrically connected to the IC module 30 via a conductive adhesive layer 60.

[0038] The thickness of the conductive plate 40 is preferably 70 μm or more and 150 μm or less, and more preferably 80 μm or more and 120 μm or less, from the viewpoint of easily setting the ratio of D2 to D1 described below to 70% or more and 98% or less.

[0039] The shape of the conductive plate 40 is not particularly limited, but may be, for example, a rectangular shape (e.g., a rectangular shape). When the conductive plate 40 is rectangular, in order to reliably ensure electrical connection with the IC module 30, the length (length in the X direction on the XY plane) of the exposed portion 41 of the conductive plate 40 is preferably 2 mm or more and 8 mm or less, and the width (length in the Y direction on the XY plane) of the exposed portion 41 of the conductive plate 40 is preferably 4 mm or more and 8 mm or less. When the conductive plate 40 is rectangular, in order to reliably ensure connection with the end 51 of the antenna 50, the length (length in the X direction on the XY plane) of the unexposed portion 42 of the conductive plate 40 is preferably 1 mm or more and 6 mm or less, and the width (length in the Y direction on the XY plane) of the unexposed portion 42 of the conductive plate 40 is preferably 1 mm or more and 8 mm or less.

[0040] The material of the conductive plate 40 is not particularly limited as long as it is a conductive material. Metallic materials such as copper and aluminum are preferred as such materials. Among these, copper is preferred from the viewpoints of cost and durability. Furthermore, the conductive plate 40 may be formed by silver-plating a copper alloy, for example, to improve weldability.

[0041] <<Antenna>> The antenna 50 is coil-shaped and is made of an antenna wire. The antenna 50 has a pair of end portions 51. The end portions 51 of the antenna 50 are electrically connected to the conductive plate 40, and therefore electrically connected to the IC module 30. This forms a communication circuit for contactless communication. The communication circuit may be one that performs close-proximity communication using an HF frequency band of 13.56 MHz, for example, or one that performs communication using another frequency band, such as a UHF frequency band of 920 MHz.

[0042] When a dual interface IC card 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 send and receive information contactlessly with the reader / writer, and to read and rewrite information from and to the memory.

[0043] The antenna wire constituting the antenna 50 is typically formed of a coated conductor wire in which the periphery of a copper wire is coated with an insulating member. 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 a coated conductor wire as the antenna wire, it can be manufactured more inexpensively than, for example, a copper foil etching method.

[0044] The diameter of the antenna wire is not particularly limited as long as it can ensure the characteristics required for a contactless communication circuit, but it can be, for example, 0.03 mm to 0.30 mm, and preferably 0.05 mm to 0.15 mm. By setting the diameter in the latter range, durability against heat and pressure during embedding and external forces due to cutting can be improved, ensuring good communication characteristics.

[0045] The end 51 of the antenna 50 has a weld 51A welded to the surface 40B of the conductive plate 40 opposite the surface 40A on the front surface 20A side of the card base 20. By forming the weld 51A on the surface 40B of the conductive plate 40, the antenna 50 and the conductive plate 40 are electrically connected, and the weld 51A can be positioned deeper than when the weld 51A is formed on the surface 40A of the conductive plate 40. The end 51 of each antenna 50 is welded to the conductive plate 40 at one location as shown in FIG. 3 , but may be welded at multiple locations to prevent the end 51 from shifting position.

[0046] In the Z direction, which is the thickness direction of the card base 20, the ratio ((D2 / D1)×100) of the depth D2 from the surface 20A of the card base 20 to the weld 51A between the end 51 of the antenna 50 and the conductive plate 40 to the depth D1 from the surface 20A of the card base 20 to the center position C, which is halfway through the thickness of the card base 20, as shown in Fig. 4, is preferably 70% or more and 98% or less. This allows the weld 51A to be closer to the center position C. The lower limit of this ratio is more preferably 75% or more, and the upper limit is more preferably 85% or less.

[0047] It is preferable that the welded portion 51A at the end 51 of the antenna 50 with the conductive plate 40 is located outside the recess 20C in the X direction, specifically, in the non-exposed portion 42 of the conductive plate 40, so that no force is applied when forming the recess 20C.

[0048] 3, the welded portion 51A at the end 51 of the antenna 50 to the conductive plate 40 extends along the Y direction, but does not have to extend along the Y direction. As shown in FIG. 3, the welded portion 51A has a tip end face 51A1 on the tip side of the antenna 50 and a base end face 51A2 on the base side of the antenna 50.

[0049] <<Conductive adhesive layer>> The conductive adhesive layer 60 is disposed between the IC module 30 and the exposed portion 41 of the conductive plate 40. By disposing the conductive adhesive layer 60, the IC module 30 and the conductive plate 40 can be electrically and mechanically connected, and therefore the IC module 30 and the antenna 50 can be electrically connected.

[0050] The conductive adhesive layer 60 can be an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP). Alternatively, a conductive paste or solder paste, in which silver particles are dispersed as a filler in an epoxy resin, can also be used. Among these, if an anisotropic conductive film is used, the anisotropic conductive film can be thermally laminated to the entire back surface of the substrate 31 of the IC module 30. The IC module 30 can then be embedded in the recess 20C of the card base 20 after cutting, and then heat-pressed at a predetermined temperature and load. This facilitates electrical connection between the IC module 30 and the conductive plate 40. Furthermore, the mechanical connection of the IC module 30 to the card base 20 can be simultaneously achieved, simplifying the process of mounting the IC module 30 on the card base 20.

[0051] The electrical connection between the IC module 30 and the conductive plate 40 and the mechanical connection between the IC module 30 and the card base 20 when an anisotropic conductive film is used as the conductive adhesive layer 60 can be explained as follows. The conductive adhesive layer 60 is composed of conductive particles, consisting of spherical resin or metal spheres surrounded by a metal film, dispersed in an adhesive binder containing adhesive components. The conductive particles may be resin coated with nickel or gold, or solder particles. Solder particles can be of various types, such as SnPb, SnAgCu, SnCu, SnZnBi, SnAgInBi, and SnZnAl, as well as alloys of these with other metals. These configurations are similar when an anisotropic conductive paste is used.

[0052] The inventors conducted extensive research into preventing wire breakage near the base of the weld where the antenna end is welded to the conductive plate when the dual interface IC card is repeatedly bent. They found that this breakage occurs due to metal fatigue caused by stress applied to the base of the weld due to repeated bending loads, and that the breakage can be prevented by positioning the weld closer to the center, which is halfway through the thickness of the dual interface IC card. Here, when comparing a case where the antenna end is welded to the surface of the conductive plate opposite the surface facing the card base with a case where the antenna end is welded to the surface of the conductive plate opposite the surface facing the card base, if the conductive plate is at the same depth in the dual interface IC card, the antenna end can be positioned closer to the center when the antenna end is welded to the surface of the conductive plate opposite the surface facing the card base, compared to a case where the antenna end is welded to the surface of the conductive plate facing the card base. Therefore, stress applied near the base of the weld where the antenna end is welded to the conductive plate when the dual interface IC card is repeatedly bent can be reduced. According to this embodiment, the end 51 of the antenna 50 has a welded portion 51A welded to the surface 40B of the conductive plate 40 opposite the surface 40A on the front surface 20A side of the card base 20, so that the antenna can be positioned closer to the center position C, which is half the thickness of the card base 20, compared to when the antenna end is welded to the surface of the conductive plate on the front surface side of the card base. This makes it possible to prevent breakage of the end 51 of the antenna 50 near the base of the welded portion 51A to the conductive plate 40 when the dual interface IC card 10 is repeatedly bent.

[0053] According to this embodiment, in the thickness direction (Z direction) of the card base 20, the ratio of the depth D2 from the surface 20A of the card base 20 to the weld 51A at the end 51 of the antenna 50 to the conductive plate 40 to the depth D1 from the surface 20A of the card base 20 to the center position C of the card base 20 is 70% or more and 98% or less, so that the depth D2 is close to the center position C. This makes it possible to prevent breakage near the base of the weld 51A at the end 51 of the antenna 50 to the conductive plate 40 when the dual interface IC card 10 is repeatedly bent.

[0054] <<Dual Interface IC Card Manufacturing Method>> When manufacturing the dual interface IC card 10, first, a multi-faceted intermediate body 70 shown in Fig. 5 is prepared. The multi-faceted intermediate body 70 is formed by attaching two or more intermediate bodies 70A together as shown in Fig. 5. In this embodiment, the IC card 10 is manufactured using the multi-faceted intermediate body 70, but the IC card 10 may also be manufactured using the intermediate body 70A alone instead of the multi-faceted intermediate body 70.

[0055] As shown in Fig. 6, each intermediate 70A is composed of a card base 20, a conductive plate 40, and an antenna 50, similar to the IC card 10, but the card base 20 does not have a recess 20C. Also, as shown in Figs. 6 and 7, the surface of the conductive plate 40 has a recess-planned region 20F where the recess 20C for arranging the IC module 30 will be formed. Note that, since a portion of the conductive plate 40 in the multi-faceted intermediate 70 and the intermediate 70A is exposed in the recess 20C when the recess 20C is formed, the conductive plate 40 is not exposed in the multi-faceted intermediate 70 and the intermediate 70A.

[0056] The multi-sided intermediate 70 can be obtained, for example, by the following manufacturing method. First, as shown in FIGS. 8A and 8B, a conductive plate 40 is placed on one surface 22A of a core layer 22 serving as a first substrate. Although the core layer 22 is used as the first substrate, the first substrate may have a layer other than the core layer 22 or a laminate structure of the core layer 22 and a layer other than the core layer 22. The conductive plate 40 may also be placed by being adhered to the surface 22A of the core layer 22.

[0057] After placing the conductive plate 40 on the surface 22A of the core layer 22, an antenna 50 having an end portion 51 is formed on the surface 22A of the core layer 22. Then, a part of the end portion 51 of the antenna 50 is welded to the surface 40B of the conductive plate 40 opposite the surface 40A in contact with the core layer 22 to form a welded portion 51A. This results in an antenna sheet 80. The conductive plate 40 and the portions of the antenna 50 other than the end portion 51 may be embedded in the surface 22A of the core layer 22.

[0058] 9A , the over-sheet layer 21, the antenna sheet 80, the inner layer 23 as the second substrate, the core layers 24 and 25, and the over-sheet layer 26 are stacked in this order to obtain a multi-faceted intermediate precursor 90. The antenna sheet 80 is positioned so that the antenna 50 faces the inner layer 23. This sandwiches the antenna 50 and the conductive plate 40 between the core layer 22 and the inner layer 23. While the inner layer 23 is used as the second substrate, the second substrate may have a layer other than the inner layer 23 or a laminate structure of the inner layer 23 and a layer other than the inner layer 23.

[0059] 9B, the multi-sided intermediate precursor 90 is sandwiched between heat-press plates 100 such as stainless steel plates from above and below in the thickness direction, and the multi-sided intermediate precursor 90 is heated and pressurized via the heat-press plates 100. By undergoing this heat-pressing process, an integrated multi-sided intermediate 70 can be obtained. Furthermore, if any of the layers constituting the multi-sided intermediate 70 are heat-resistant and 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 heat-pressing process can be performed to obtain the integrated multi-sided intermediate 70.

[0060] After forming the multi-faceted intermediate body 70, the intermediate body 70A is punched out from the multi-faceted intermediate body 70 and separated into individual pieces. Then, as shown in FIG. 10A, a first recess 20D is formed along the outer periphery of the recess-planned region 20F of the card base 20 in the intermediate body 70A. Specifically, the card base 20 is cut from the surface 20A of the card base 20 in the depth direction of the card base 20 (-Z direction) along the outer periphery of the recess-planned region 20F. This cutting of the card base 20 is continued until a portion of the conductive plate 40 is exposed.

[0061] 10B, a portion of the bottom surface 20D1 of the first recess 20D is further cut to form the second recess 20E. This cutting is performed so that the hole diameter of the second recess 20E is smaller than the hole diameter of the first recess 20D. This results in a card base 20 having a recess 20C consisting of the first recess 20D and the second recess 20E, and having a step between the bottom surfaces 20D1 and 20E1.

[0062] Meanwhile, as shown in FIG. 11A, a conductive adhesive layer 60 is formed on the terminals 33 of the IC module 30.

[0063] 11B, the terminals 33 and the conductive plate 40 are electrically connected via the conductive adhesive layer 60, and the IC module 30 is placed in the recess 20C so that the molded portion 35 is positioned in the second recess 20E. As a result, the IC module 30 and the antenna 50 are electrically connected via the conductive adhesive layer 60, and the dual interface IC card 10 is obtained. [Example]

[0064] In order to explain the present invention in detail, examples are given below, but the present invention is not limited to these descriptions.

[0065] Example 1 Two conductive copper plates, each 6 mm long, 6 mm wide, and 0.1 mm thick, were attached to a predetermined area on one side of an upper core layer (Diafix PG-WHI, manufactured by Mitsubishi Chemical Corporation) made of a 0.19 mm thick glycol-modified PET resin (PET-G resin). An antenna made of copper wire with a diameter of 0.11 mm was then embedded in the above-mentioned surface of the core layer. A portion of the end of the antenna was then welded to the exposed surface of the conductive plate opposite the surface in contact with the upper core layer, forming a 2 mm long weld. This resulted in an antenna sheet.

[0066] Then, a transparent upper over-sheet made of 0.05 mm thick PET-G resin ("Diafix PG-MCT" manufactured by Mitsubishi Chemical Corporation), an antenna sheet, an upper inner layer made of 0.16 mm thick PET-G resin ("Diafix PG-WHI" manufactured by Mitsubishi Chemical Corporation), a lower inner layer made of 0.16 mm thick PET-G resin ("Diafix PG-WHI" manufactured by Mitsubishi Chemical Corporation), a lower core layer made of 0.19 mm thick PET-G resin ("Diafix PG-WHI" manufactured by Mitsubishi Chemical Corporation), and a transparent lower over-sheet made of 0.05 mm thick PET-G resin ("Diafix PG-MCT" manufactured by Mitsubishi Chemical Corporation) were laminated in this order to form an intermediate precursor. In the intermediate precursor, the antenna sheet was positioned so that the antenna was on the upper inner layer side. The intermediate precursor was then sandwiched between heat press plates, heated to 140°C, and pressed at 2 MPa to integrate the precursor, resulting in an intermediate comprising a card base having an upper over-sheet layer, an upper core layer, an upper inner layer, a lower inner layer, a lower core layer, and a lower over-sheet layer, a conductive plate, and an antenna.

[0067] After obtaining the intermediate, the intermediate was removed from the heat press plate and then punched out to obtain an intermediate having a length of 85.60 mm and a width of 53.98 mm. The intermediate was then cut from the upper over-sheet layer side until the conductive plate was exposed, forming a first recess having a length of 13.0 mm, a width of 11.8 mm, and a depth of 0.24 mm.

[0068] Next, in the intermediate body with the first recess formed, the bottom surface of the first recess was further machined to form a second recess measuring 9 mm in length, 9 mm in width, and 0.70 mm in depth, thereby forming a recess consisting of the first recess and the second recess.

[0069] On the other hand, an anisotropic conductive film was attached to the IC module, and then the IC module with the anisotropic conductive film was embedded in the recess by applying heat and pressure so that the anisotropic conductive film was in contact with the exposed part of the conductive plate, and the terminals of the IC module and the conductive plate were electrically connected via the anisotropic conductive film.

[0070] This resulted in a dual interface IC card having an overall thickness of 0.80 mm, a depth D2 from the surface of the card base to the weld of 0.290 mm, and a ratio of the depth D2 of the weld to the depth D1 from the surface of the card base to the center position C, which is half the thickness of the card base, of 72.5%.

[0071] <Example 2> In Example 2, a dual interface IC card was obtained in the same manner as Example 1, except that the thickness of the upper oversheet and the lower oversheet was changed from 0.05 mm to 0.10 mm, the upper inner layer and the lower inner layer were changed to a single inner layer of 0.21 mm, making the overall thickness 0.79 mm, the depth of the first recess 0.29 mm, the depth D2 of the welded portion 0.340 mm, and the ratio of the depth D2 of the welded portion to the depth D1 of the central position 86.0%.

[0072] Example 3 In Example 3, a dual interface IC card was obtained in the same manner as Example 1, except that the thickness of the upper oversheet and the lower oversheet was changed from 0.05 mm to 0.15 mm, the upper inner layer and the lower inner layer were changed to a single inner layer with a thickness of 0.12 mm, making the overall thickness 0.8 mm, the depth of the first recess 0.34 mm, the depth D2 of the weld 0.390 mm, and the ratio of the depth D2 of the weld to the depth D1 of the central position 97.5%.

[0073] <Comparative Example 1> In Comparative Example 1, the antenna sheet was positioned so that the welded portion between the end of the antenna and the conductive plate was on the surface side of the dual interface IC card, the thicknesses of the upper and lower over-sheets were changed from 0.05 mm to 0.15 mm, the upper and lower inner layers were changed to single inner layers with a thickness of 0.12 mm, making the overall thickness 0.8 mm, the depth D2 of the welded portion and the depth of the first recess 0.150 mm, and the ratio of the depth D2 of the welded portion to the depth D1 of the central position 37.5%. A dual interface IC card was obtained in the same manner as in Example 1, except for this.

[0074] <Comparative Example 2> In Comparative Example 2, a dual interface IC card was obtained in the same manner as Comparative Example 1, except that the thickness of the upper oversheet and the lower oversheet was changed from 0.05 mm to 0.20 mm, the upper inner layer, the lower inner layer and the lower core layer were changed to a single lower core layer with a thickness of 0.21 mm, making the overall thickness 0.8 mm, the depth D2 of the weld and the depth of the first recess 0.200 mm, and the ratio of the depth D2 of the weld to the depth D1 of the central position 50.0%.

[0075] <Comparative Example 3> In Comparative Example 3, the conductive plate and antenna were formed on the upper inner layer instead of the upper core layer, and the welded portion at the end of the antenna to the conductive plate was positioned on the front side of the dual interface IC card. The thickness of the upper inner layer was changed from 0.16 mm to 0.19 mm, the thickness of the lower core layer was changed from 0.19 mm to 0.16 mm, making the overall thickness 0.8 mm, the depth D2 of the welded portion and the depth of the first recess 0.240 mm, and the ratio of the depth D2 of the welded portion to the depth D1 of the central position 60.0%. Except for this, a dual interface IC card was obtained in the same manner as in Example 1.

[0076] <Repeated bending test> The dual interface IC cards according to Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to a repeated bending test to evaluate whether or not breakage occurred at the welded portion between the antenna end and the conductive plate. Specifically, a wrapping test was conducted in accordance with the Mastercard (registered trademark) CQM requirement TM-422 test method, in which the dual interface IC cards were repeatedly bent 500 times, 1000 times, 1500 times, and 2000 times. Five dual interface IC cards were prepared and each was subjected to the bending test. The evaluation criteria were as follows. Note that if even one card received a result of "B," the repeated bending test was not conducted any further. A: No breaks occurred in the welds of any of the five dual interface IC cards. B: Disconnections occurred in the welds of 1 to 4 dual interface IC cards.

[0077] The results are shown in Table 1. In Table 1, "-" means that the repeated bending test was not performed. [Table 1]

[0078] In the dual interface IC cards according to Comparative Examples 1 to 3, the welded portion at the end of the antenna to the conductive plate was on the front side of the dual interface IC card, so breakage occurred at the welded portion when subjected to a repeated bending test of 500 to 2000 times. In contrast, in the dual interface IC cards according to Examples 1 to 3, the welded portion at the end of the antenna to the conductive plate was on the back side of the dual interface IC card, so breakage did not occur at the welded portion even when subjected to a repeated bending test of 500 to 2000 times. [Explanation of symbols]

[0079] 10...Dual interface IC card 20...Card base 20A…Surface 20C...recess 30...IC module 34...IC chip 40...Conductive plate 40A, 40B...plane 50...antenna 51...End 60…Conductive adhesive layer

Claims

1. A dual interface IC card capable of contact communication and contactless communication with an external device, a card base having a recess on its surface; an IC module disposed in the recess; a conductive plate disposed inside the card base and partially exposed within the recess; an antenna disposed inside the card base; a conductive adhesive layer disposed between the IC module and a portion of the conductive plate exposed in the recess, electrically connecting the IC module and the conductive plate; A dual interface IC card, wherein an end of the antenna has a welded portion welded to a surface of the conductive plate opposite to the surface on the front side of the card base.

2. 2. The dual interface IC card according to claim 1, wherein the ratio of the depth from the surface of the card base to the welded portion to the depth from the surface of the card base to the center position of the card base in the thickness direction of the card base is 70% or more and 98% or less.

3. A dual interface IC card capable of contact communication and contactless communication with an external device, a card base having a recess on its surface; an IC module disposed in the recess; a conductive plate disposed inside the card base and partially exposed within the recess; an antenna disposed inside the card base; a conductive adhesive layer disposed between the IC module and a portion of the conductive plate exposed in the recess, electrically connecting the IC module and the conductive plate; an end of the antenna having a weld welded to one surface of the conductive plate; A dual interface IC card, in which the ratio of the depth from the surface of the card base to the welded portion to the depth from the surface of the card base to the center position of the card base in the thickness direction of the card base is 70% or more and 98% or less.

4. 4. The dual interface IC card according to claim 1, wherein the conductive adhesive layer is an anisotropic conductive film.

5. 4. The dual interface IC card according to claim 1, wherein the conductive adhesive layer is an anisotropic conductive paste layer.

6. 4. The dual interface IC card according to claim 1, wherein the thickness of said conductive plate is 70 [mu]m or more and 150 [mu]m or less.

7. An intermediate used in manufacturing a dual interface IC card capable of contact communication and contactless communication with an external device, a card base having a recessed portion on its surface in a predetermined area for forming a recessed portion for arranging an IC module; a conductive plate disposed inside the card base and electrically connected to the IC module; an antenna disposed inside the card base, an intermediate body, the end of the antenna being welded to a surface of the conductive plate opposite to the surface of the card base facing the front side;

8. An intermediate used in manufacturing a dual interface IC card capable of contact communication and contactless communication with an external device, a card base having a recessed portion on its surface in a predetermined area for forming a recessed portion for arranging an IC module; a conductive plate disposed inside the card base and electrically connected to the IC module; an antenna disposed inside the card base, An intermediate body in which, in the thickness direction of the card body, the ratio of the depth from the surface of the card body to the welded portion with the conductive plate at the end of the antenna to the depth from the surface of the card body to the center position of the card body is 70% or more and 98% or less.

9. A method for manufacturing a dual interface IC card capable of contact communication and contactless communication with an external device, comprising: disposing a conductive plate on one surface of a first substrate; forming an antenna having an end on the surface of the first substrate; a step of welding a portion of the end of the antenna to a surface of the conductive plate opposite to a surface in contact with the first base material to form a weld; forming a card body by laminating at least the first substrate and the second substrate by thermal fusion or via an adhesive so as to sandwich the antenna and the conductive plate; a step of cutting the card base from the front surface side of the card base to form a recess and expose a part of the conductive plate in the recess; a step of disposing a conductive adhesive layer on a terminal of an IC module having an IC chip and a terminal electrically connected to the IC chip; and placing the IC module in the recess so that the terminals and the conductive plate are electrically connected via the conductive adhesive layer, The method for manufacturing a dual interface IC card, wherein the welded portion is located on the surface of the conductive plate opposite to the surface on the front side of the card base.

10. 10. The method for manufacturing a dual interface IC card according to claim 9, wherein the ratio of the depth from the surface of the card base to the welded portion to the depth from the surface of the card base to the center position of the card base in the thickness direction of the card base is 70% or more and 98% or less.

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