Metal Card

Abstract

To provide a metal card for enabling non-contact communication and improving the stability of non-contact communication performance by using slit technology (a coupling frame) even in the metal card made of metal.SOLUTION: In a metal card with a core layer including metal, an opening is provided on the front surface of the metal card, an IC module is installed in the opening, and a slit extending from one end of the opening to a card end part is formed, and has a tapered shape such that the width of a slit end of the card end side is gradually spread.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a metal card with a contactless communication function, which is used for credit cards, debit cards, cash cards, access control cards, etc. In particular, it relates to a technology for improving the stability of contactless communication performance in electromagnetically coupled cards that use slit technology (coupling frame technology). [Background technology]

[0002] There is a known electromagnetic wave communication system that includes a contactless IC card and a reader / writer that has a transmitter / receiver unit including an antenna coil and a control unit and performs electromagnetic wave communication with the contactless IC card. Contactless IC cards use Faraday's law to generate magnetic flux by passing an electric current through the antenna coil of the reader / writer, and the antenna coil of the contactless IC card receives this magnetic flux and generates electricity through electromagnetic induction, and the IC chip communicates via the generated electric current (electromagnetic induction coupling).

[0003] In conventional contactless IC cards, the antenna coil and IC chip are physically connected on the card (see Patent Document 1). In order to increase the robustness of IC cards against mechanical stress, there is also technology that provides a small coil on the IC chip side and electromagnetically couples it to eliminate the physical connection between the antenna coil and IC chip of the IC card.

[0004] Furthermore, with the aim of increasing card ownership motivation among card users, there is growing demand for cards made entirely of luxurious metal. Metal cards also offer the advantages of improved mechanical protection and protection from ultraviolet rays. However, metal is a conductive material and has the property of blocking electromagnetic waves, which tends to attenuate the performance of contactless communication. Therefore, contactless communication is not possible, and cards are often used only in contact mode.

[0005] A card using coupling frame technology has been proposed as a card constructed entirely from metal and capable of contactless communication (see Patent Document 2). This card has an opening in the metal layer on the surface where an IC module is attached, and a slit extending from the opening to the edge of the metal layer. When the card is subjected to a magnetic field from a reader / writer, an induced current that opposes the magnetic flux is generated according to Faraday's law, as mentioned above. Furthermore, due to the skin effect, this induced current flows along the edge of the card. As a result, current flows through the slit and along the metal edge, electrically coupling the IC module and enabling contactless communication. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-28037 [Patent Document 2] U.S. Patent Application Publication No. 2014 / 361086 Summary of the Invention [Problem to be solved by the invention]

[0007] The slits in the coupling frame card also function as capacitors. The larger the volume formed in the slit section of the coupling frame card, the more the communication performance tends to improve, so the slit width is often designed to be the processing limit of 50 μm to 200 μm. However, if the slit width is designed narrow like this, the metal will deform when external stress is applied to the outer part of the card, and the slit will not fit in the outer part of the card. If the slit shorts out, there is a problem that almost no current flows into the IC module opening, resulting in a significant drop in performance.

[0008] The present invention solves the above-mentioned problems, and its purpose is to provide a metal card that uses slit technology (coupling frame) to enable contactless communication even in a metal card made of metal, and improves the stability of contactless communication performance. [Means for solving the problem]

[0009] In order to solve the above problems in the present invention, the first aspect of the present invention is A metal card having a core layer containing metal, The metal card is characterized by having an opening on the front of the metal card, an IC module installed in the opening, a slit extending from one end of the opening to the end of the card, and a tapered shape in which the width of the slit end on the card end side gradually widens.

[0010] In addition, a second aspect of the present invention is The slit may have a tapered shape so that the width of the slit end on the opening side gradually increases.

[0011] Moreover, a third aspect of the present invention is A metal card having a core layer containing metal, An opening is provided on the front surface of the metal card, an IC module is installed in the opening, and a slit is formed extending from one end of the opening to an end of the card; The slit has a tapered shape in which the width of the slit end on the card end side or the slit end on the opening side gradually increases, The metal card is characterized in that the gaps in the slits are impregnated with resin to fill the gaps.

[0012] Moreover, a fourth aspect of the present invention is The resin may be a high dielectric constant resin.

[0014] The present invention improves robustness against external loads such as distortion of the card, and even if the card is distorted and the slit width changes, the widened end becomes less likely to short-circuit than usual, preventing the occurrence of defects. [Effects of the Invention]

[0015] In the present invention, even for metal cards made of metal, it is possible to provide a metal card that enables contactless communication and improves the stability of contactless communication performance by using slit technology (coupling frame). [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a plan view of a conventional metal card with slits. [Figure 2] 1 is a plan view of a metal card with slits according to a first embodiment of the present invention. [Figure 3] FIG. 10 is a plan view of a metal card with slits according to another example of the first embodiment of the present invention. [Figure 4] 1 is a cross-sectional view showing the layer structure of a metal card according to an embodiment of the present invention. [Figure 5] 1A to 1C are diagrams illustrating a method for forming a slit shape according to the present invention. [Figure 6] 10(a) is a plan view of a metal card with slits according to embodiment 2 of the present invention, and (b) is a plan view of another example of a metal card with slits according to embodiment 2. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] In conventional dual IC cards, the antenna coil and IC module were physically connected on the card. However, to improve the robustness of IC cards against mechanical stress and improve productivity, the antenna was printed and incorporated on the back of the IC module substrate, and technology was developed to electrically connect the antenna and module through electromagnetic coupling. However, as mentioned above, when the entire card is made of metal, metal is a conductive material and has the property of blocking electromagnetic waves, which attenuates the performance of contactless communication and makes contactless communication impossible. This invention uses slit technology (coupling frame) to enable contactless communication even on metal cards, and further improves performance stability by making the slit less likely to short-circuit.

[0018] Figure 1 shows a metal card 1 with a conventional slit 11. The edges of the slit 11 may be subject to stress in the thickness direction of the card, and the large surface thickness compared to the small cross-sectional area of ​​the card may cause the metal to deform easily. Furthermore, when the slit 11 is formed and then punched into individual card pieces, the metal at the edge of the card may be crushed, potentially changing the shape of the slit. Thus, with the conventional slit shape, there is a risk of a short circuit when an external load is applied to the card 1. If the slit 11 shorts out, almost no current can flow into the IC module opening 10, significantly reducing performance.

[0019] [Embodiment 1] The slit shape of the metal card 2 according to the first embodiment of the present invention will be described with reference to Fig. 2. As described above, it is conceivable that the slit shape of the slit end 12 on the card end side will change due to an external load. However, in contrast, it is thought that the slit 11 in the center of the slit is less likely to deform because a protective layer (exterior substrate) is generally provided on the front and back surfaces of the card 2. Taking the above into consideration, by making the slit end 12 on the card end side have a tapered shape that gradually widens the slit width as shown in Fig. 2, it is possible to avoid short circuits even when an external load is applied to the card 2.

[0020] Furthermore, as shown in FIG. 3, the slit end 13 on the IC module opening 10 side may also be tapered to widen the slit width.

[0021] <Card layer composition> Next, the layer structure of the card will be described with reference to FIG. A metal plate is used as the core layer 5 that mainly constitutes the metal card 2. Materials that can be used for the metal plate include iron, stainless steel, copper, nickel, tin, zinc, tungsten, and alloys based on these. Furthermore, the metal plate is not limited to metal only; for example, it may be constructed by combining a metal layer with polyvinyl chloride (PVC). The IC module opening 10 and the slit 11 extending from the IC module opening 10 to the edge of the card are formed by any method, such as cutting, laser processing, or electrical discharge machining.

[0022] As shown in Fig. 4, a protective layer may be formed by sandwiching the front and back of the core layer 6 with exterior substrates 5. Materials commonly used for card substrates, such as polyvinyl chloride (PVC) and polyethylene terephthalate copolymer (PET-G), are used as the material for the exterior substrate 5. It is preferable to bond the core layer 6 to the metal layer by disposing an adhesive layer between them.

[0023] Furthermore, the printing layer 4, which comprises the image, letters, etc., can be formed by a known printing method such as offset printing or silk screen printing. A protective layer, etc., can also be provided on the printing layer 4. Finally, the metal card is formed by punching into individual card pieces by punching. Obtain the card body 2.

[0024] Next, an IC module opening 10 for attaching the IC module 7 is provided on the front surface of the metal card body 2. At this time, the metal layer is processed so as not to be exposed on the surface, so that the electromagnetic coupling antenna coil (not shown) provided on the back surface of the IC module 7 does not come into direct contact with the metal of the card core layer 6. Alternatively, an insulator may be sandwiched between the metal layer and the IC module substrate (not shown).

[0025] <Opening size> The opening size will be described using a six-terminal IC module as an example. The size of the six-terminal IC module 6 is 10.5 mm × 7.9 mm. The IC module opening 10 must be smaller than the module size to prevent the IC module 6 from falling off. A mold (not shown) is applied to the back of the module to protect the wire bonds that electrically connect the IC to the substrate. This mold size is approximately 5 mm in diameter. By making the IC module opening 10 larger than this, contact between the metal card body 2 and the IC module 6 can be prevented, damaging the IC module 6 or the wire bonds and resulting in malfunction. Therefore, the size of the opening 10 for a six-terminal IC module must be larger than 5 mm × 5 mm but smaller than 10.5 mm × 7.9 mm. Using a similar approach, the opening size 10 for an eight-terminal IC module can also be appropriately determined.

[0026] <Slit width> The slit 11 provided between the IC module opening 10 and the card edge functions as a capacitor. To obtain a capacitor that improves RF performance, the width of the slit 11 tends to be narrower. However, since the slit is mainly formed by drilling, it is often designed to be within the drilling limit of 50 μm to 200 μm.

[0027] <Tapered shape> There are various methods for forming a tapered shape where the slit width gradually widens at the slit edge 12 on the card edge side, but one method is to make a V-cut as shown in Figure 5. After making a slit 11 in the metal card 2 as usual, the slit edge 12 on the card edge side is processed with a V-cut blade 14 to form the desired shape. As an example of a tapered shape, a taper of 30 degrees can be formed on both the top and bottom sides toward the slit edge, starting from a position 1 mm away from the slit edge toward the center.

[0028] [Embodiment 2] Next, a metal card 3 according to a second embodiment of the present invention will be described with reference to FIG. Another method can be considered to make the width of slit 11 less likely to deform even if distortion occurs to card 3. Resin 8 is impregnated into the gaps of slit 11. As shown in Figure 6(a), by compressing thermosetting resin 8 by transfer molding or other methods into the areas of slit 11 where the metal is missing, resin 8 can prevent short circuits between the slits even if card 3 is distorted and a force is applied in the direction that shrinks the width of slit 11.

[0029] Furthermore, the slit portion 11 functions as a capacitor, and in order to obtain a higher capacitance, it is more desirable that the impregnated resin 8 has a high dielectric constant. For example, polycarbonate with a high dielectric constant can be used.

[0030] As shown in FIG. 6(b), this may be combined with a method in which the slit end 12 on the card end side and the slit end 13 on the opening side are tapered.

[0031] As described above, according to the present invention, even with a metal card made of metal, contactless communication is possible using slit technology (coupling frame), and the slits are designed to be less likely to short-circuit, thereby improving the stability of communication performance. [Explanation of symbols]

[0032] 1. Conventional metal cards with slits 2. Metal card according to the first embodiment of the present invention 3. Metal card according to the second embodiment of the present invention 4...printing layer 5...Exterior base material 6. Core layer (metal layer) 7. IC module 8...Thermosetting resin 10. IC module opening 11. Slit 12 Slit end on the card edge 13....Slit edge on the opening side 14···V-cut blade

Claims

1. A metal card having a core layer containing metal, The metal card is characterized in that an opening is provided on the front surface of the metal card, an IC module is installed in the opening, a slit is formed extending from one end of the opening to the end of the card, and the end of the slit on the card end side is tapered so as to gradually widen in width.

2. 2. The metal card according to claim 1, wherein the slit has a tapered shape such that the width of the slit end on the opening side gradually increases.

3. A metal card having a core layer containing metal, A metal card characterized in that an opening is provided on the front surface of the metal card, an IC module is installed in the opening, a slit is formed extending from one end of the opening to the end of the card, the slit has a tapered shape so that the width of the slit end on the card end side or the slit end on the opening side gradually increases, and the gap space of the slit is impregnated with resin to fill the gap.

4. 4. The metal card according to claim 3, wherein the resin is a resin with a high dielectric constant.

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