Contactless Metal Transaction Cards, And A Compound Filled Recess For Embedding An Electronic Component

20220414406 · 2022-12-29

    Inventors

    Cpc classification

    International classification

    Abstract

    A transaction card having a front “continuous” (with no slit) metal layer (530, 630, 730) with an opening (506, 612, 712) for a dual-interface transponder chip module (510, 610, 710). A shielding layer (540, 640, 742) comprising ferrite material (shielding layer) disposed below the metal layer. An amplifying element (507, 650, 744) disposed under the shielding layer. A metal interlayer (750, FIG. 7B) with a slit to function as a coupling frame (CF). A coupling frame antenna (507) having a single turn or track mounted on a supporting substrate (502). A rear plastic layer (560, 660, 760) formed of non-RF impeding material may capture a magnetic stripe and security elements (signature panel and hologram). The coupling frame antenna (507) may be integrated into the rear plastic layer. A portion of the front metal layer may protrude downward into the shielding layer. A dielectric spacer (548, 648, 748) may be disposed between the shielding layer and the amplifying element. A compound-filled recess for embedding an electronic component is also disclosed.

    Claims

    1. Smartcard having a card body comprising: a front metal layer (730) having a first module opening (MO; 712); a shielding layer (742) disposed behind the front metal layer; a booster antenna circuit (BAC; 744) disposed behind the shielding layer; and a metal interlayer or layers (750) each having a second module opening (714) and a slit (720); wherein the front metal layer does not have a slit extending from a peripheral edge of the front metal layer to the first module opening.

    2. The smartcard of claim 1, further comprising: a dielectric spacer (738) disposed between the front metal layer and the shielding layer.

    3. The smartcard of claim 1, wherein: a portion of the front metal layer protrudes downward into an opening in the shielding layer.

    4. The smartcard of claim 1, wherein: the metal interlayer or layers is disposed behind the booster antenna circuit.

    5. The smartcard of claim 1, wherein: the metal interlayer or layers is disposed between the front metal layer and the booster antenna circuit.

    6. The smartcard of claim 1, further comprising: a protective hard coat layer (724) disposed on the front metal layer.

    7. The smartcard of claim 1, further comprising: a print layer (726) disposed between the hard coat layer and the front metal layer.

    8. The smartcard of claim 1, further comprising: a transparent, translucent or white synthetic layer (760) disposed behind the metal interlayer or layers.

    9. The smartcard of claim 8, further comprising: at least one of primer (762) and ink (764) disposed on the synthetic layer.

    10. The smartcard of claim 8, further comprising: a laser engravable overlay layer (770) disposed behind the synthetic layer.

    11. The smartcard of claim 1, further comprising: a dual-interface module (710) inserted into the module openings of the card body.

    12. Transaction card having at least contactless capability comprising: a dual interface transponder chip module (TCM; 500A,B) having a dual interface RFID chip and a module antenna; a metal layer (530) having a module opening (506) and no slit; a radio frequency shielding layer (540) comprising ferrite material disposed behind the metal layer; and a coupling frame antenna (CFA) on a support substrate (502) disposed behind the shielding layer and comprising a single turn or track having a slit or gap extending from an outer edge of the coupling frame antenna to an inner position thereof, wherein the slit or gap of the coupling frame antenna is disposed to overlap at least a portion of the module antenna.

    13. The transaction card of claim 12, further comprising: a dielectric spacer disposed between the front metal layer and the shielding layer.

    14. The transaction card of claim 12, wherein: a portion of the metal layer protrudes downward into an opening in the shielding layer.

    15. The transaction card of claim 12, further comprising: at least one plastic layer (560) disposed behind the support substrate.

    16. The transaction card of claim 15, further comprising: a magnetic stripe and security elements disposed on the plastic layer.

    17. The transaction card of claim 12, further comprising: a second coupling frame antenna having a slit or gap extending from an outer edge of the coupling frame antenna to an inner position thereof, and stacked with the coupling frame antenna; and a dielectric layer disposed between the coupling frame antenna and the second coupling frame antenna.

    18. The transaction card of claim 12, wherein: the slit is disposed to overlap at least a portion of the module antenna.

    19. The transaction card of claim 12, wherein: the coupling frame antenna is configured to inductively couple to the dual interface transponder chip module.

    20. The transaction card of claim 12, wherein: the coupling frame antenna is physically connected in series or parallel with the module antenna of the dual interface transponder chip module.

    21. The transaction card of claim 12, wherein: the coupling frame antenna is physically connected to pads linked to antenna connections La and Lb on the dual interface chip.

    22. An RFID-enabled metal transaction card comprising: a front face metal layer (ML; 530, 630, 730) with a module opening for a chip module, and without a slit extending from a peripheral edge of the front metal layer to the module opening; wherein the card is capable of operating in contactless mode from the rear side of the card body.

    23. The transaction card of claim 22, further comprising: a shielding layer disposed behind the front metal layer.

    24. The transaction card of claim 23, further comprising: a dielectric spacer disposed between the metal layer and the shielding layer.

    25. The transaction card of claim 23, wherein: a portion of the metal layer protrudes downward into an opening in the shielding layer.

    26. The transaction card of claim 22, further comprising: a rear synthetic layer (560, 660, 760).

    27. The transaction card of claim 22, wherein: the card has an activation distance of at least 4 cm.

    28. The transaction card of claim 22, wherein: the card has drop acoustics which sound like metal.

    29. The transaction card of claim 22, further comprising: a shielding layer (540, 640, 742) disposed behind the front face metal layer; and an amplifying element (CFA, CF, BAC) disposed behind the shielding layer.

    30. Smartcard having a card body comprising: a front metal layer (630) having a module opening (MO; 612); a shielding layer (640) disposed behind the front metal layer; and a coupling frame (CF; 650) disposed behind the shielding layer; wherein the front metal layer does not have a slit extending from a peripheral edge of the front metal layer to the module opening.

    31. The smartcard of claim 30, further comprising: a dielectric spacer (638) disposed between the front metal layer and the shielding layer.

    32. The smartcard of claim 30, wherein: a portion of the metal layer protrudes downward into an opening in the shielding layer.

    33. The smartcard of claim 30, further comprising: a protective hard coat layer 624) disposed on the front metal layer.

    34. The smartcard of claim 33, further comprising: a print layer (626) disposed between the hard coat layer and the front metal layer.

    35. The smartcard of claim 30, further comprising: a metal interlayer or layers (650) disposed behind the shielding layer.

    36. The smartcard of claim 35, further comprising: a transparent, translucent or white synthetic layer (660) disposed behind the metal interlayer or layers.

    37. The smartcard of claim 36, further comprising: at least one of primer (662) and ink (664) disposed on the synthetic layer; and a laser engravable overlay layer (670) disposed behind the synthetic layer.

    38. The smartcard of claim 30, further comprising: a dual-interface module (610) inserted into the module openings of the card body.

    39. A process for manufacturing an RFID-enabled metal transaction card comprising the steps of: CNC milling an opening in a card body of the transaction card; filling the opening partially or entirely with a compound; mechanically forming the compound as a structure having the shape and dimensions of an electronic component; and inserting the electronic component into the formed compound structure.

    40. The process of claim 39, wherein the step of forming the compound comprises: applying an ultrasonic tool or hot stamp to the compound under pressure and temperature to compress and shape the compound to accept the insertion of the electronic component.

    41. The process of claim 39, wherein the step of inserting the electronic component comprises: placing the electronic component with an adhesive backing layer into the formed compound using heat and pressure.

    42. The process of claim 41, wherein: the step of inserting the electronic component is performed after the step of forming the compound.

    43. The process of claim 39, further comprising the step of: creating one or more securing features in the card body for securing the formed compound material to the card body.

    44. The process of claim 43, wherein: the securing features comprise pockets in the card body.

    45. The process of claim 39, wherein: the CNC milled opening extends partially or entirely through the card body.

    46. The process of claim 39, wherein: the compound material is an epoxy resin having a forming temperature range which can withstand high paint bake temperatures of approximately 300-400° F.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0106] Reference will be made in detail to embodiments of the disclosure, non-limiting examples of which may be illustrated in the accompanying drawing figures (FIGs). The figures may generally be in the form of diagrams. Some elements in the figures may be stylized, simplified or exaggerated, others may be omitted, for illustrative clarity.

    [0107] Although the invention is generally described in the context of various exemplary embodiments, it should be understood that it is not intended to limit the invention to these particular embodiments, and individual features of various embodiments may be combined with one another. Any text (legends, notes, reference numerals and the like) appearing on the drawings are incorporated by reference herein.

    [0108] Some elements may be referred to with letters (“AS”, “CBR”, “CF”, “MA”, “MT”, “TCM”, etc.) rather than or in addition to numerals. Some similar (including substantially identical) elements in various embodiments may be similarly numbered, with a given numeral such as “310”, followed by different letters such as “A”, “B”, “C”, etc. (resulting in “310A”, “310B”, “310C”), and may collectively (all of them at once) referred to simply by the numeral (“310”).

    [0109] FIG. 1A (compare FIG. 1 of 62/932,506; FIG. 3A of U.S. Pat. No. 10,275,703) is a cross-sectional diagram of a smart metal card with ferrite shield formed between the card and chip antennas and the cards' metal layer, according to the prior art.

    [0110] FIG. 1B (compare FIG. 2 of 62/932,506; FIG. 6B of U.S. Pat. No. 10,275,703) is a simplified partial cross-sectional view of a dual interface smart card, according to the prior art.

    [0111] FIG. 1C (compare FIG. 4 of 62/932,506; FIG. 4 of U.S. Pat. No. 10,318,859) is a cross-sectional diagram of the layers of a metal-containing card body with booster antenna and shielding layer, according to the prior art.

    [0112] FIG. 2 (compare FIG. 3 of 62/932,506; FIG. 16B of U.S. Pat. No. 9,836,684) is a diagram (exploded perspective view) of a shielded metal laminated smartcard (RFID device), according to the prior art.

    [0113] FIGS. 3A, B (compare FIGS. 1A, B of 62/964,138; FIGS. 5A and 5B of U.S. Pat. No. 9,697,459) are two perspective views (front and back) of a metal card body MCB having a cavity (MO) for a transponder chip module (TCM, not shown), and a slit S extending from the cavity to an outer edge of the metal card body, according to the prior art.

    [0114] FIG. 3C (compare FIG. 2 of 62/964,138; FIG. 3 of U.S. Pat. No. 5,550,402) is part details of consecutive stages of manufacture of an electronic module, based on a system support, according to the prior art.

    [0115] FIG. 4A (compare FIG. 3A of 62/964,138; FIG. 3A of US 2019/0050706) is a schematic illustration of the front of a transaction card prior to insertion molding, according to the prior art.

    [0116] FIG. 4B (compare FIG. 3B of 62/964,138; FIG. 3B of US 2019/0050706) is a schematic illustration of the rear of a transaction card prior to insertion molding, according to the prior art.

    [0117] FIG. 4C (compare FIG. 3C of 62/964,138; FIG. 3C of US 2019/0050706) is a schematic illustration of the front of a transaction card after insertion molding, according to the prior art.

    [0118] FIG. 4D (compare FIG. 3D of 62/964,138; FIG. 3D of US 2019/0050706) is a schematic illustration of the rear of a transaction card after insertion molding, according to the prior art.

    [0119] FIG. 5A (compare FIG. 5 of 62/932,506) is a diagram (exploded perspective view) of a shielded metal laminated transaction card with a coupling frame antenna (CFA), according to an embodiment of the invention.

    [0120] FIG. 5B is a modified diagram of FIG. 5A with additional features showing the stack-up construction of a dual interface metal face smartcard with contactless tap to pay function on one side of the card body, according to an embodiment of the invention.

    [0121] FIG. 6A is a diagram (exploded perspective view) of the stack-up construction of a dual interface metal face smartcard with contactless tap to pay function on one side of the card body having a metal interlayer with slit to function as a coupling frame (CF), according to an embodiment of the invention.

    [0122] FIG. 6B is a modified diagram of FIG. 6A showing a stack-up construction of a dual interface metal face smartcard with contactless tap to pay function on one side of the card body, having a front face solid metal layer without a discontinuity with its rear surface having an off-center protruding metal section, according to an embodiment of the invention.

    [0123] FIG. 6C is a modified diagram of FIG. 6B showing the stack-up construction of a dual interface metal face smartcard with contactless tap to pay function on one side of the card body, having a front face solid metal layer without a discontinuity attached to an underlying frame of anti-shielding material, according to an embodiment of the invention.

    [0124] FIG. 7A is a diagram (exploded perspective view) of the stack-up construction of a dual interface metal face smartcard with contactless tap to pay function on one side of the card body having a booster antenna circuit (BAC) in combination with an underlying metal interlayer having a slit to function as a coupling frame or coupling frame antenna, according to an embodiment of the invention.

    [0125] FIG. 7B is a similar diagram to FIG. 7A showing the stack-up construction of a dual interface metal face smartcard with contactless tap to pay function on one side of the card body having a metal interlayer with a slit to function as a coupling frame or a coupling frame antenna, above an underlying ferrite layer having a booster antenna circuit, with the top coupling frame and bottom booster antenna circuit sandwiching a ferrite layer, according to an embodiment of the invention.

    [0126] FIG. 8A (compare FIG. 4 of 62/964,138) is a side view of a transaction card showing a metal card body with an opening to accept the implanting of an inductive coupling chip module and the corresponding dimensions thereof with a rear synthetic layer (laser engravable overlay) capturing the security elements (not shown), and ready for lamination to the metal layer, according to an embodiment of the invention.

    [0127] FIG. 8B (compare FIG. 5 of 62/964,138) is a side view of a transaction card showing a metal card body with the opening to accept the implanting of the inductive coupling chip module and the synthetic layer laminated to the metal layer, according to an embodiment of the invention.

    [0128] FIG. 8C (compare FIG. 6 of 62/964,138) is a side view of a transaction card showing a metal card body with the opening filled with a compound and cured to a solid state, according to an embodiment of the invention.

    [0129] FIG. 8D (compare FIG. 7 of 62/964,138) is a side view of a transaction card embodying the invention showing a metal card body with the compound structure machined to have a recess area matching the shape and dimensions of the inductive coupling chip module, according to an embodiment of the invention.

    [0130] FIG. 8E (compare FIG. 8 of 62/964,138) is a side view of a transaction card showing a metal card body with an inductive coupling chip module implanted in the machined recessed area having interior walls composed of the compound structure, according to an embodiment of the invention.

    [0131] FIG. 9A (compare FIG. 9 of 62/964,138) is a front elevation view of a transaction card embodying the invention showing a slit commencing at a perimeter edge of the metal card body and terminating at the inductive coupling chip module, with the slit exhibiting a semi-circle opening shape at both ends of the slit, according to an embodiment of the invention.

    [0132] FIG. 9B (compare FIG. 10 of 62/964,138) is a front elevation view of a transaction card embodying the invention showing a slit commencing at a perimeter edge of the metal card body and terminating at the inductive coupling chip module, with the slit exhibiting a delta (triangular) opening shape at both ends of the slit, according to an embodiment of the invention.

    DESCRIPTION

    [0133] Various embodiments (or examples) may be described to illustrate teachings of the invention(s), and should be construed as illustrative rather than limiting. It should be understood that it is not intended to limit the invention(s) to these particular embodiments. It should be understood that some individual features of various embodiments may be combined in different ways than shown, with one another. Reference herein to “one embodiment”, “an embodiment”, or similar formulations, may mean that a particular feature, structure, operation, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Some embodiments may not be explicitly designated as such (“an embodiment”).

    [0134] The embodiments and aspects thereof may be described and illustrated in conjunction with systems, devices and methods which are meant to be exemplary and illustrative, not limiting in scope. Specific configurations and details may be set forth in order to provide an understanding of the invention(s). However, it should be apparent to one skilled in the art that the invention(s) may be practiced without some of the specific details being presented herein.

    [0135] Furthermore, some well-known steps or components may be described only generally, or even omitted, for the sake of illustrative clarity. Elements referred to in the singular (e.g., “a widget”) may be interpreted to include the possibility of plural instances of the element (e.g., “at least one widget”), unless explicitly otherwise stated (e.g., “one and only one widget”).

    [0136] In the following descriptions, some specific details may be set forth in order to provide an understanding of the invention(s) disclosed herein. It should be apparent to those skilled in the art that these invention(s) may be practiced without these specific details. Any dimensions and materials or processes set forth herein should be considered to be approximate and exemplary, unless otherwise indicated. Headings (typically underlined) may be provided as an aid to the reader, and should not be construed as limiting.

    [0137] Reference may be made to disclosures of prior patents, publications and applications. Some text and drawings from those sources may be presented herein, but may be modified, edited or commented to blend more smoothly with the disclosure of the present application.

    [0138] Dual Interface Metal Cards with a Ferrite Layer

    [0139] FIG. 1A includes a sectional view of metal substrate 30 having an exterior (outer) surface 361 and an inner surface 351. After groove 32 is formed on the inner surface 351, ferrite material 33 and an adhesive such as epoxy, cyanoacrylate, silicone based system or thermoplastic adhesive are applied into the channel defined by the groove 32. The ferrite 33 may be applied as a die cut sheet or as a ferrite slurry acrylic oligomer intermediate which will harden under UV exposure or after the slurry solvent is driven off. It should be noted that the ferrite 33 is preferably applied so as to be below the inner surface of the substrate 30 and to rise up to the surface of the card at the edges of groove 32. Note the antenna wires cannot be completely encased or completely shielded by the ferrite layer. That is the ferrite shield cannot completely surround the antenna.

    [0140] The ferrite shield 33 overlies card (booster) antenna 24. A plastic layer 18 is formed below subassembly 36a. Layer 18 contains and includes a module 20, which contains a microprocessor chip 20a and a chip antenna 20b coupled to chip 20a.

    [0141] Note that contact pad 20c is on the opposite side of the metal substrate.

    [0142] In operation, ferrite material 33 deposited in groove 32 shields antenna 24 (and chip antenna 20b) from metal substrate 30, to make it possible for RF radiation to enter and be emitted from antenna 24.

    [0143] A metal surface interferes with RF radiation in that it absorbs incident RF signals with the metal acting as a virtual ground. The ferrite layer formed between the card antenna 24 (including chip antenna 20b) and the metal layer 30 reflects incident RF signals so they are not absorbed by the metal layer.

    [0144] Note that a reader (not shown) would be positioned to interrogate the smart card from the non-metallic side of the card for contactless operation.

    [0145] As set forth in some claims of U.S. Pat. No. 10,275,703: [0146] 1. A metal smart card comprising: a plastic layer having a top surface; a metal layer overlying the plastic layer, said metal layer having an inner surface; a groove formed within the inner surface of said metal layer; a card antenna comprising antenna windings disposed within said groove and wound along the top surface of or within said plastic layer; and a strip of RF shielding material lining said groove and disposed between the inner surface of the metal layer and the antenna windings, said strip of RF shielding material overlying the antenna windings and limited to a length and a width sufficient to track the underlying antenna windings to form an RF shield between the antenna windings and the metal layer. [0147] 2. The metal smart card of claim 1, wherein the antenna windings are wound adjacent to an outer periphery of the plastic layer.

    [0148] In FIG. 1A, the subassembly 36a includes a metal substrate 361 and a plastic chip carrier layer 18. The metal layer 361 is shown with a ferrite shield 33 attached to the groove 32 and with a booster card antenna 24 formed (wound) directly within the ferrite shielded groove.

    [0149] Alternatively, the coils of a booster antenna may be formed on, or within, a plastic layer. Ferrite material is formed or placed substantially only over the coil layout area to provide an RF shield and a metal layer can then be attached over the shielded coils to form a smart metal card with a limited amount of ferrite material.

    [0150] FIG. 1B is a simplified partial cross-sectional view of a dual interface smart card 30. The contact pad 20c is on the same side/surface as the exterior (outer) surface of the metal layer 30. The card antenna 124 is shielded with a ferrite layer.

    [0151] The ferrite may be applied as a die cut sheet or as a ferrite slurry which will harden under UV exposure or after the solvent is driven off. Substrate 30 is formed with a through bore 30a, which is shaped to receive an RFID module 20, which contains a microprocessor chip 20a, an antenna 20b and a contact pad 20c. Pad 20c is a conventional contact pad used in contact-type smart cards and is positioned to engage contacts in a card reader when the smart card is inserted therein. Antenna 20b is shown to project below metal substrate 30, for example, by about 0.01 inch.

    [0152] Formed below substrate 30 is a plastic layer 134 having an antenna 124 formed by winding the coils (windings) 24a within a plastic layer 134. Layer 134 is formed with a recess shaped to receive the portion of antenna 20b that extends below substrate 30. This permits antenna 20b to extend in close proximity to antenna 124.

    [0153] Preferably, the ferrite shield 33 extends laterally beyond winding 124 by at least 0.005 inches, in order to ensure that substrate 30 will not interfere with transmission or reception by antenna 124.

    [0154] As shown in FIG. 1C, a metal-containing card body may include the following structure:

    [0155] A metal layer 30 is intended to serve as the top layer of a card. The metal layer 30 has a top (front) surface 301 and a bottom (back) surface 302 and a thickness (D) which may range from less than 0.01 inches to more than 0.02 inches.

    [0156] A plug 434 of any material which does not interfere with RF transmission is formed or shaped to conform to the dimensions of the hole/opening to fill the cut out region. Plug 434 is processed and functions to secure the IC module. The interior walls of the hole and/or the exterior walls of the plug 434 is/are coated with a suitable adhesive so the plug 434 adheres firmly to the walls of the hole/opening throughout the processing of the metal layer in the formation of the card. The plug 434 may be made of any thermoplastic material such as PET, PVC or other polymer or any material such as epoxy resins and a ceramic.

    [0157] An adhesive layer 42 is used to attach a ferrite layer 44 to the back surface 302 of layer 30. An adhesive layer 46 is used to attach a plastic (e.g., PVC) layer 48 which contains and/or on which is mounted a booster antenna 47 to the ferrite layer. Layers 42, 44, 46, and 48 and the booster antenna 47 are formed in a similar manner as the corresponding number components shown in FIG. 2 and serve the same or similar functions. The assembly comprising layers 30, 42, 44, 46 and 48 is laminated to form a card assembly.

    [0158] A layer 52, which includes a signature panel and a magnetic stripe, may be attached to layer 48 before or after lamination.

    [0159] IC module 7 which includes a chip 7a and a chip antenna 7b and a set of contacts 7c is positioned within hole/opening and is glued in place. Physical connections extend between the booster antenna 47 and the chip antenna 7b.

    [0160] Unlike other designs known in the art, a deliberately large gap between the chip and the sides of the opening is not required to provide suitable RF functionality.

    [0161] As outlined in U.S. Pat. No. 10,289,944, the plug provides support for the IC module and a degree of electrical insulation and isolation from the metal layer.

    [0162] Shielded Laminated Smartcard

    [0163] FIG. 2 shows a shielded, laminated metal laminated shielded card (SC) 1600B having two coupling frame metal layers and a front face (ML1) which is a continuous metal layer (no slit). Some of the metal layers are the same (or similar) to those shown in the construction of FIG. 16A of U.S. Pat. No. 10,193,211.

    [0164] Notably different, however, is that the top metal layer (ML1) does not have a slit (there is no “S1” in this embodiment). The second metal layer (ML2) has a slit (S2), and the third metal layer (ML3) has a slit (S3), as in the construction of FIG. 16A of U.S. Pat. No. 10,193,211, and the various layers may be held together (laminated) with layers of adhesive, as shown. The dimensions of the various layers may be similar to those in the construction of FIG. 16A of U.S. Pat. No. 10,193,211.

    [0165] The front face (ML1) 1620A, as shown, does not have a slit, and may interact with the reader electromagnetic field and produce induced eddy currents within its body. These eddy currents will normally produce a counter-field resulting in reduction or blocking of the communication between the transponder chip module and reader. To offset this, a shielding layer (SL) 1640 of suitably chosen magnetic material may be placed between the front continuous metal layer and the coupling frame layers (ML2, ML3) of the card. A layer of adhesive 1622 having a thickness of 20 μm may be disposed between the front metal layer ML1 and the shielding layer SL. A layer of adhesive 1623 having a thickness of 20 μm may be disposed between the shielding layer SL and the second metal layer ML2.

    [0166] The front metal layer (ML1) may have a thickness of 200 μm, rather than 300 μm (or 320 μm) as in the construction of FIG. 16A of U.S. Pat. No. 10,193,211. The shielding layer (SL) may have a thickness of approximately 50-200 μm, such as 100 μm (which was gained by making the front layer thinner than in the construction of FIG. 16A). In this manner the coupling frames will be shielded from the attenuating front metal layer and continue to function in conjunction with the transponder chip module (TCM).

    [0167] Other elements of the FIG. 2 embodiment, such as the second metal layer ML2 and third metal layer ML3 may be substantially similar or identical to corresponding (similarly numbered) elements in the embodiment of FIG. 16A of U.S. Pat. No. 10,193,211. Generally, the top metal layer ML1 of FIG. 16A of U.S. Pat. No. 10,193,211 is replaced by a metal layer ML1 without a slit and a shielding layer SL.

    [0168] The module antenna (MA) of the transponder chip module (TCM) may reside in a plane that lies below the continuous front metal layer (ML1). The module antenna (MA) may be surrounded on all edges (sides) by magnetic shielding material (not shown) to reduce the attenuation from eddy currents in the front metal layer (ML1). In this manner the performance of the magnetic shielding material may be maximized and the coupling of the transponder chip module (TCM) with the coupling frame layers (ML2, ML3) may be improved.

    [0169] The prior art is silent on the retention of the metal sound with the card body comprising of material (several adhesive layers and a magnetic shielding layer) which dampens the drop acoustics of the metal card.

    [0170] FIGS. 3A, 3B are two views (front and back) of a metal card body (MCB) 502 having a cavity (MO) 508 which is an opening for the transponder chip module (not shown) and a slit (S) 530 extending from the cavity to an outer edge of the metal card body. A reinforcing insert 540 is shown inserted into the card body at the position of the slit S.

    [0171] Reference may be made to FIG. 8 of US 2015/0021403 (22 Jan. 2015; Finn et al.; U.S. Pat. No. 9,798,968) which shows a metal smart card (SC) 800 comprising a full metal card body (CB) 802 with an opening (MO) 808 for a transponder chip module (TCM, not shown) and a slit (S) 830 extending from the opening (MO) to a periphery of the card body (CB) to allow the flux lines to propagate around the area of the transponder chip module (TCM). The full metal card body (CB) may be formed of an electrically conductive material, such as titanium, may have a thickness of 760 μm and may act as a coupling frame (CF) for inductive coupling with a contactless reader or point of sale terminal. The card body (CB) may comprise conductive nanoparticles.

    [0172] To reinforce the card body (CB) (or metal layer (ML)) having a slit (S), a reinforcing insert (or structure or plate), of a non-conductive material such as plastic or reinforced plastic, may be disposed at (including around and covering) the location (area) of the slit (S) in a recess (R, not shown) on the underside of the card body (CB), and may extend beyond the slit. For example, the slit (S) may be 50 μm wide, the reinforcing structure may be up to or more than 8000 μm wide (approximately the size of a side of the TCM). The reinforcing structure (RS) may have a logo or design. The thickness of the reinforcing structure (and corresponding depth of the recess R on the underside of the card body CB) may be 350 μm. The opening (MO) may extend completely through the card body (CB) and the transponder chip module (TCM) may extend through the opening (MO) to the underside of the card body (CB) to allow the propagation of the electromagnetic flux lines.

    [0173] FIG. 3C shows the finished shape of an intermediate product and its casing 10. Injection molding has filled with plastic material all the slits 23 and 24 as far as the webs 28, including all perforations 31. The plastic material finishes everywhere flush with the outer face of the system support 20 which was supported on the bottom half 40 of the mold. The plastic material for the casing 10 should preferably be a duroplastic synthetic resin having a low coefficient of thermal expansion, such as is generally known and used for embedding silicon chips, i.e. so-called low-stress material which contains a large proportion of quartz. By contrast, the metal used for the system support 20 has a high coefficient of thermal expansion, and therefore expands in the mold because of the temperature of the injected plastic. Later, as the metal cools, it shrinks again and encloses the plastic that fills the perforations 31 as it hardens, and thus produces a very strong compression fit of high density. This results in a mechanically stable bond between the metal parts and the resin of the casing, yet does not require the plastic resin to spread beyond the metal parts during injection molding, nor the metal to be deformed or machined in its thickness. Once the plastic casing 10 is formed, as shown in FIG. 3 of U.S. Pat. No. 5,550,402, the intermediate product taken from the mold is then further processed.

    [0174] FIGS. 4A-4D show selected steps of an insert molding process for manufacturing a transaction card are depicted. In the figures, areas 305 and 308 in FIGS. 4A-4D represent holes through the cards. Area 307a,b in FIG. 4A and area 307c in FIGS. 4B and 4D represent partially covered holes (pockets) in the card body for the molding material to bind and find purchase. FIG. 4B depicts the completed molded card in which the insert molded material of molded component 310 is visible.

    [0175] Although the insert molded material is shown contrasting with the background card materials for purposes of illustration, the molded component is not limited to any particular degree of contrast in coloration or shading relative to the background card, and may comprise the same materials as the front of the card or may comprise materials selected to have a coloration or shading selected to match the coloration or shading of the front, side of the card so as to minimize its visibility in a completed card. For example, in a card body comprising materials different than the molding materials (e.g. a metal or ceramic body and thermoplastic resin molding materials), the coloration of the molding materials may be selected have a color and tone that matches as closely as possible the material of the body, including using constituents in the molding materials that are the same or similar to the card body materials (e.g. inclusion of a powdered metal in the molding materials that is the same as the metal of the body). Molding materials that contrast with the body of the card may be used. FIG. 4A depicts the front side of a transaction card 300 including an opening 305 which extends entirely through a card body 302. A plurality of securing features 307a, b provide areas to which the molding material can adhere or otherwise bind. In the depicted illustration, securing features 307a,b are blind holes (e.g., pockets). A similar set of securing features 307c are found on the opposing rear side of transaction card 300 in FIG. 4B. The geometries of opening 305 and securing features 307a, b, c were selected to improve the RF performance of the metal transaction card 300. Securing features 307a, b, c may comprise a material that is the same or otherwise compatible with the molding material, and different than the card body material, such that the molding material and the materials of the securing features melt or otherwise join together with a bond that is relatively stronger than any bond created between the molding material and the card body.

    [0176] FIG. 4C depicts the front side of the transaction card 300 after an insert molded electronic component 310 has been placed into opening 305. In the depicted illustration, molded electronic component 310 would be visible on transaction card 300. The geometry of molded electronic component 310 permits molded electronic component 310 to become secured to transaction card 300 through a biasing action created by securing features 307a,b,c. Alternatively, or additionally, molded electronic component 310 may be adhered to opening 305 of transaction card 300 using an epoxy resin such as Bisphenol, Novolac, Aliphatic, and Glycidylamine.

    [0177] Excess molding material may be removed from molded electronic component 310 (by, e.g., milling or machining) to incorporate additional electronic components or other desired components.

    [0178] Shielded Metal Laminated Transaction Card with Coupling Frame Antenna

    [0179] FIG. 5A shows the following exemplary stack-up of layers for a card 500A, from a front surface (side) of the card to a rear surface (side) of the card: [0180] a front metal layer (ML) 530 having a module opening 506, and no slit (“continuous”) compare “530” in FIG. 5B [0181] an adhesive layer 522 (also having a module opening) [0182] a shielding layer (SL) 540 (also having a module opening) [0183] an adhesive layer 523 (also having a module opening) [0184] a support layer 502 having a module opening 508 [0185] a coupling frame antenna (“CFA”) 507 formed on the support layer 502, the coupling frame antenna having a slit portion 503 and a portion surrounding the module opening 508 [0186] an adhesive layer 524 (optionally having a module opening) [0187] a rear plastic layer (PL) 560 (no module opening)

    [0188] A dual-interface transponder chip module (TCM) 510 may be inserted into the module openings in the various layers of the card 500A.

    [0189] FIG. 5A is a diagrammatic view of a shielded metal laminated transaction card 500A, generally comprising (from top-to-bottom, as viewed): a 6 or 8 pin (contact pad) dual interface transponder chip module (TCM) 510, a top (front) metal layer (ML) 530 which may have a thickness of approximately 300 or 400 μm. Notably different to the prior art, however, is that the top metal layer (ML) does not have a slit. The continuous front metal layer may comprise titanium, aluminum, brass or stainless steel.

    [0190] The front face metal layer 530, as shown, does not have a slit, and may interact with an electromagnetic field produced by an external reader (such as a POS terminal) to produce induced eddy currents within its metal body. These eddy currents will normally produce a counter-field resulting in reduction or blocking of the communication between the dual interface transponder chip module and the reader.

    [0191] To offset the counter-field, a shielding layer (SL) 540 of magnetic material, such as ferrite, on an insulating layer may be disposed between the front metal layer 530 and a coupling frame antenna (CFA) which is disposed on a supporting substrate 502.

    [0192] A layer of adhesive 522 having a thickness of 20 μm may be disposed between the front metal layer (ML) and the shielding layer (SL). A layer of adhesive 523 having a thickness of 20 μm may be disposed between the shielding layer (SL) and the bottom coupling frame antenna (CFA) on the supporting substrate 502. A slit (S) 503 is shown extending from the left edge of the coupling frame antenna (CFA) to an opening (MO) 508 for the dual interface transponder chip module (TCM) 510. Optionally, a capacitor may be connected across the slit portion of the coupling frame antenna (CFA).

    [0193] The coupling frame antenna (CFA) on the supporting substrate may not have an opening MO, but rather may simply have a portion encircling a position defined for the dual interface transponder chip module. The coupling frame antenna (CFA) is shown having a portion defining a slit (S) extending from a periphery of the card to the position of the transponder chip module to overlap and couple with the module antenna (aka a micro-antenna) of the transponder chip module. See, for example, U.S. Pat. No. 10,552,722, incorporated by reference herein, which discloses: [0194] FIG. 2 of U.S. Pat. No. 10,552,722 is a diagram of an exemplary coupling frame antenna (CFA) with a track width of approximately 3 mm. The design shown illustrates a continuous closed loop single track coupling frame antenna (CFA) 202 placed within the perimeter defined by the card body (CB) 201. It is noted that the figure is illustrative of the shape and overall form of the coupling frame antenna (CFA) 202 and that the antenna may reside upon or between any of the layers that may make up a typical smartcard. The outer edges of the coupling frame antenna (CFA) 402 may extend to the periphery of the card body (CB) 201 or be offset from the edge of the smartcard by some distance to aid lamination or other assembly of the smartcard's additional layers. The path defined by the coupling frame antenna (CFA) 201 extends inwards towards and around the module opening (MO) 204. The length, width and track thickness of the coupling frame antenna (CFA) 202 in the vicinity of the module opening (MO) 204 may be set as to provide an optimum overlap with the module antenna (MA) of the transponder chip module (TCM). [0195] The shape of the coupling frame antenna, as it extends inwardly from the left (as viewed) side of the card body to the module opening area, results in two side-by-side portions of the coupling frame antenna (CFA) being closely adjacent each other, with a gap therebetween. This gap may be comparable to the slit (S) in a conventional coupling frame (CF).

    [0196] With the construction shown in FIG. 5A, the coupling frame antenna will be shielded from the RF-attenuating front metal layer (ML) and continue to function in conjunction with the dual interface transponder chip module (TCM).

    [0197] The module antenna (MA) of the transponder chip module may be substantially surrounded (on all sides) by magnetic shielding material (not shown) to reduce attenuation from eddy currents in the front metal layer (ML).

    [0198] In this manner, the performance of the magnetic shielding material (540) may be maximized and the coupling of the dual interface transponder chip module (TCM) 510 with the coupling frame antenna (CFA) 502 may be improved.

    [0199] The rear plastic layer (PL) 560 capturing (supporting) a magnetic stripe and security elements (not shown) of the transaction card may be attached to the supporting substrate 502 for the CFA by means of the adhesive layer 524.

    [0200] The coupling frame antenna (CFA) may alternatively reside in (be disposed upon) the rear plastic layer (PL). The module antenna (MA) of the dual interface transponder chip module (TCM) may reside in a plane that lies below the front metal layer (ML).

    [0201] The module antenna (MA) may be physically connected to the coupling frame antenna (forming a series or parallel RLC circuit). The coupling frame antenna may be connected via connection tracks or wire bonds to the antenna pads L.sub.a and L.sub.b of the dual interface transponder chip.

    [0202] A second coupling frame antenna (not shown) having a slit or gap extending from an outer edge of the coupling frame antenna (CFA) to an inner position thereof may be provided wherein the slit or gap is disposed to overlap at least a portion of the module antenna, and a dielectric layer may be disposed between the two coupling frame antennas. The two coupling frame antennas can be stacked, one atop the other, with a dielectric therebetween, in the manner of the metal interlayers (650) discussed below.

    [0203] FIG. 5B is a diagram of the stack-up construction of a dual interface metal face smartcard 500B with contactless tap to pay function on one side of the card body, generally comprising (from top-to-bottom, as viewed):

    [0204] The stack-up construction of the card body 500B (smartcard (SC) or transaction card (TC)) with a front face continuous metal layer without a discontinuity may comprise the following layers:

    [0205] CFA: Coupling frame antenna (CFA) 507 formed on a support layer 550, the coupling frame antenna having a slit portion 503 and a portion surrounding the module opening 508

    [0206] 510: Transponder chip module (TCM) or inductive coupling chip module (ICM);

    [0207] 524: Protective hard coat layer (5-10 μm)—a lamination hard top-coat film or a printed coating (ink, varnish or a polymer) which can be laser marked or laser engraved;

    [0208] 526: A print layer which may compose of: (i) a digital, silk screen, lithographic or thermo-graphic layer of clear or colored ink, (ii) a baked-on-ink layer, (iii) a PVD or DLC coating, or (iv) a combination thereof, including an adhesion promoter or primer applied between the metal layer 530 and subsequent coatings;

    [0209] 530: Front face metal layer with a module opening (MO) 606 and without a slit (“continuous”, no slit) which may have a print layer 526, typically having a thickness of 150 μm;

    [0210] 538: Adhesive layer (25 μm)—thermosetting epoxy—to attach the ferrite layer 540 to the rear side of the front face metal layer 530;

    [0211] 540: High permeability magnetic sheet shielding layer with a thickness of 50 μm or 100 μm which may compose of the following: calcium carbonate (CaCO.sub.3), silicon dioxide (SiO.sub.2), magnesium fluoride (MgF.sub.2), SiO2, chromium (Cr) and iron (Fe), to offset the effects of electromagnetic shielding caused by the front face metal layer 530; the shielding layer may comprise ferrite particles in a binder or on a support layer

    [0212] 548: Adhesive layer (25 μm)—thermosetting epoxy—spanning the entire width and length of the card body, being assembled to the rear side of the front face metal layer 530 and to the ferrite layer 540;

    [0213] 550: Support layer for the coupling frame antenna 503;

    [0214] 558: Adhesive layer (25 μm)—thermosetting epoxy—spanning the entire width and length of the card body;

    [0215] 560: Transparent, translucent or white synthetic layer (e.g. PVC, PC, PETG), typically 150 μm;

    [0216] 562 primer;

    [0217] 564 ink (printed information (PI)); The position of 562 and 564 may be interchangeable depending on the printing process.

    [0218] 570: Laser engravable overlay layer (PVC), typically 64 μm;

    [0219] 574: Magnetic stripe;

    [0220] 576: Operation of laser marking the rear overlay layer with personalization data;

    [0221] Security elements (signature panel and hologram are not shown.

    [0222] FIG. 6A is a diagram of the stack-up construction of a dual interface metal face smartcard 600A with contactless tap to pay function on one side of the card body, having a front face solid metal layer 630 without a discontinuity attached to underlying layers by means of an adhesive system which does not dampen the inherent metal sound of the card body. The metal interlayer 650 has a slit (S), a module opening (MO) 614 to accept the insertion of a transponder chip module 610 for inductive coupling.

    [0223] The stack-up construction of the card body (CB) 600A (smartcard (SC) or transaction card (TC)) with a front face continuous metal layer without a discontinuity may comprise the following layers:

    [0224] 610: dual-interface Transponder Chip Module (TCM) or inductive coupling module (ICM);

    [0225] 612: P1 Module opening (MO);

    [0226] 614: P2 Module opening (MO);

    [0227] 620: Slit (S) in the metal interlayer acting as a coupling frame for contactless communication;

    [0228] 676: Operation of laser marking the rear overlay layer with personalization data;

    [0229] 624: Protective hard top-coat layer (5-10 μm)—a hard top-coat lamination film or a deposited coating (ink, varnish or a polymer) which can be laser marked or laser engraved;

    [0230] 626: A print layer (25 μm) which may compose of: (i) a digital, silk screen, lithographic or thermo-graphic layer of clear or colored ink (ii) a baked-on-ink layer, (iii) a PVD or DLC coating, or (iv) a combination thereof, including an adhesion promoter or primer applied between the metal layer 630 and subsequent coatings;

    [0231] 630: Front face metal layer with a module opening 612 and without a slit (“continuous”) which may have a print layer 626, typically the metal layer having a thickness of 150 μm;

    [0232] 638: Adhesive layer (25 μm)—thermosetting epoxy—to attach the ferrite layer 640 to the rear side of the front face metal layer 630;

    [0233] 640: High permeability magnetic sheet shielding layer with a thickness of 50 μm or 100 μm which may compose of the following: calcium carbonate (CaCO.sub.3), silicon dioxide (SiO.sub.2), magnesium fluoride (MgF.sub.2), SiO2, chromium (Cr) and iron (Fe), to offset the effects of electromagnetic shielding caused by the front face metal layer 630;

    [0234] 648: Adhesive layer (25 μm)—thermosetting epoxy—to attach the ferrite layer 640 to the front side of the metal interlayer 650 with slit 620;

    [0235] 650: Metal interlayer or layers with a slit 620 (300-350 μm);

    [0236] This is comparable to the CFA's shown in FIGS. 5A,B

    [0237] If there are two metal layers with slits, they may be separated by a dielectric or insulating layer, such as adhesive.

    [0238] 658: Adhesive layer (25 μm)—thermosetting epoxy—to attach the metal interlayer 650 to the front side of the synthetic layer 660;

    [0239] 660: Transparent, translucent or white synthetic layer (e.g. PVC, PC, PETG), typically having a thickness of 150 μm;

    [0240] 662 primer;

    [0241] 664 ink (printed information (PI));

    [0242] The positions of 662 and 664 may be interchangeable depending on the printing process.

    [0243] 670: Laser engravable overlay layer (PVC), typically having a thickness of 64 μm;

    [0244] 674: Magnetic stripe;

    [0245] Security elements (signature panel and hologram are not shown.

    [0246] FIG. 6B is a modified diagram of FIG. 6A showing a stack-up construction of a dual interface metal face smartcard 600B with contactless tap to pay function on one side of the card body, having a front face solid metal layer 630 without a discontinuity with its rear surface having a protruding metal section (a boss) 632, which may be off-center. The metal interlayer 650 has a slit (S), a module opening (MO) 614 to accept the insertion of a transponder chip module 610 for inductive coupling.

    [0247] The boss 632 is a portion of the metal layer 630 that is deformed to protrude downward from the metal layer 630, and fit snugly into a corresponding hole 641 in the underlying ferrite layer 640. This helps protect the card body against delamination. Contrast this with FIGS. 1A,B having ferrite 32 protruding up into the metal 30 above. This feature (the metal layer protruding down into the underlying shielding layer) may be applied to other embodiments shown herein, whether or not explicitly shown and described.

    [0248] The stack-up construction of the card body (CB) 600B (smartcard (SC) or transaction card (TC)) with a front face continuous metal layer without a discontinuity may comprise the following layers:

    [0249] 610: Transponder chip module (TCM) or inductive coupling chip module (ICM);

    [0250] 612: P1 Module opening (MO);

    [0251] 614: P2 Module opening (MO);

    [0252] 620: Slit (S) in the metal interlayer acting as a coupling frame for contactless communication;

    [0253] 676: Operation of laser marking the rear overlay layer with personalization data;

    [0254] 624: Protective hard top-coat layer (5-10 μm)—a hard top-coat lamination film or a deposited coating (ink, varnish or a polymer) which can be laser marked or laser engraved;

    [0255] 626: A print layer (25 μm) which may compose of: (i) a digital, silk screen, lithographic or thermo-graphic layer of clear or colored ink, (ii) a baked-on-ink layer, (iii) a PVD or DLC coating, or (iv) a combination thereof, including an adhesion promoter or primer applied between the metal layer 630 and subsequent coatings;

    [0256] 630: Front face metal layer without a slit which may have a print layer 626, typically the metal layer having a thickness of 150 μm—with its rear surface having an off-center protruding metal section (a boss) 632 (e.g. 25 mm×30 mm) having a stepped ledge 636 having a height equal to the thickness of the underlying adhesive layer 638 and the ferrite layer 640, approximately 75 μm or 125 μm;

    [0257] 638: Adhesive layer (25 μm)—thermosetting epoxy—to attach the ferrite layer 640 to the rear side of the front face metal layer 630 having an opening for the protruding metal section 632;

    [0258] 640: High permeability magnetic sheet layer with a thickness of 50 μm or 100 μm which may compose of the following: calcium carbonate (CaCO.sub.3), silicon dioxide (SiO.sub.2), magnesium fluoride (MgF.sub.2), SiO2, chromium (Cr) and iron (Fe), to offset the effects of electromagnetic shielding caused by the front face metal layer 630;

    [0259] 648: Adhesive layer (25 μm)—thermosetting epoxy—spanning the entire width and length of the card body, being assembled to the protruding metal section (a boss) 632 on the rear side of the front face metal layer 630 and to the ferrite layer 640 which is flush with the outer surface of the protruding metal section (a boss) 632;

    [0260] 650: Metal interlayer or layers with a slit 620 (300-350 μm); a metal layer with a module opening (MO) and a slit (S) may be referred to as a coupling frame (CF)

    [0261] 658: Adhesive layer (25 μm)—thermosetting epoxy—to attach the metal interlayer 650 to the front side of the synthetic layer 660;

    [0262] 660: Transparent, translucent or white synthetic layer (e.g. PVC, PC, PETG), typically having a thickness of 150 μm;

    [0263] 662 primer;

    [0264] 664 ink (printed information (PI));

    [0265] The position of 662 and 664 may be interchangeable depending on the printing process.

    [0266] 670: Laser engravable overlay layer (PVC), typically having a thickness of 64 μm;

    [0267] 674: Magnetic stripe;

    [0268] Security elements (signature panel and hologram are not shown.

    [0269] So, in FIG. 6B, there is a continuous metal layer 630 with an opening 612 and without a slit, under which is a ferrite shielding layer 640, under which is a discontinuous metal layer (or frame) 650 with slit and opening.

    [0270] FIG. 6C is a modified diagram of FIG. 6B showing a stack-up construction of a dual interface metal face smartcard 600C with contactless tap to pay function on one side of the card body, having a front face solid metal layer 630 without a discontinuity with its rear surface having a protruding metal layer 633 which fits into a frame comprising of anti-shielding material. The metal interlayer 650 has a slit (S), a module opening (MO) 614 to accept the insertion of a transponder chip module 610 for inductive coupling.

    [0271] The stack-up construction of the card body (CB) 600C (smartcard (SC) or transaction card (TC)) with a front face continuous metal layer without a discontinuity may comprise the following layers:

    [0272] 610: Transponder chip module (TCM) or inductive coupling chip module (ICM);

    [0273] 612: P1 Module opening (MO);

    [0274] 614: P2 Module opening (MO);

    [0275] 620: Slit (S) in the metal interlayer acting as a coupling frame for contactless communication;

    [0276] 676: Operation of laser marking the rear overlay layer with personalization data;

    [0277] 624: Protective hard top-coat layer (5-10 μm)—a hard top-coat lamination film or a deposited coating (ink, varnish or a polymer) which can be laser marked or laser engraved;

    [0278] 626: A print layer (25 μm) which may compose of: (i) a digital, silk screen, lithographic or thermo-graphic layer of clear or colored ink, (ii) a baked-on-ink layer, (iii) a PVD or DLC coating, or (iv) a combination thereof, including an adhesion promoter or primer applied between the metal layer 630 and subsequent coatings;

    [0279] 630: Front face metal layer without a slit which may have a print layer 626, typically the metal layer having a thickness of 150 μm—with its rear surface having a protruding metal layer 633 having a stepped ledge 637 having a height equal to the thickness of the underlying adhesive frame layer 638 and the ferrite frame layer 640, approximately 75 μm or 125 μm;

    [0280] 638: Adhesive frame layer (25 μm)—thermosetting epoxy—to attach the ferrite frame layer 640 to the rear side of the front face metal layer 630 having an opening for the protruding metal layer 633;

    [0281] 640: High permeability magnetic sheet layer with a thickness of 50 μm or 100 μm made of polymer magnetic sheet technology to offset the electromagnetic attenuation caused by the front face metal layer 630; This ferrite layer 640 has an oversize hole 643 (compare 641, FIG. 6B) for receiving the protrusion from the overlying metal layer 630. The hole is very large, such as 35 mm by 65 mm or smaller, resulting in a band (or ring) of ferrite material, approximately 10 mm wide, being disposed around the periphery of the underlying supporting layer. (The ID-1 spec for the size of the card is approximately 86 mm×54 mm)

    [0282] 648: Adhesive layer (25 μm)—thermosetting epoxy—spanning the entire width and length of the card body, being assembled to the protruding metal layer 633 on the rear side of the front face metal layer 630 and to the ferrite frame layer 640 which is flush with the outer surface of the protruding metal layer 633;

    [0283] 650: Metal interlayer or layers with a slit 620 (300-350 μm); a metal layer with a module opening (MO) and a slit (S) may be referred to as a coupling frame (CF)

    [0284] 658: Adhesive layer (25 μm)—thermosetting epoxy—to attach the metal interlayer 650 to the front side of the synthetic layer 660;

    [0285] 660: Transparent, translucent or white synthetic layer (e.g. PVC, PC, PETG), typically having a thickness of 150 μm;

    [0286] 662 primer;

    [0287] 664 ink (printed information (PI));

    [0288] The position of 662 and 664 may be interchangeable depending on the printing process.

    [0289] 670: Laser engravable overlay layer (PVC), typically having a thickness of 64 μm;

    [0290] 674: Magnetic stripe;

    [0291] Security elements (signature panel and hologram are not shown.

    [0292] FIG. 7A is a diagram (exploded perspective view) of the stack-up construction of a dual interface metal face smartcard 700A with contactless tap to pay function on one side of the card body having a booster antenna circuit 744 mounted on a magnetic shielding layer 742 in combination with a metal interlayer 750 having a slit to function as a coupling frame. The front face solid metal layer 730 is continuous metal layer with no discontinuity. The metal interlayer 750 has a slit (S) 720, a module opening (MO) 714 to accept the insertion of a transponder chip module 710 with its module antenna inductively coupling with the coupler coil of the booster antenna 744 and the slit 720 in the metal interlayer 750. The metal interlayer 750 with slit may be replaced by a coupling frame antenna (CFA).

    [0293] The stack-up construction of the card body (CB) 700A (smartcard (SC) or transaction card (TC)) with a front face continuous metal layer without a discontinuity may comprise the following layers (all dimensions are exemplary and approximate):

    [0294] 710: dual-interface Transponder Chip Module (TCM) or inductive coupling module (ICM);

    [0295] 712: P1 Module opening (MO), in front face metal layer (ML1) 730 without a slit

    [0296] 714: P2 Module opening (MO), in metal interlayer or layers 750 with a slit 720

    [0297] 720: Slit (S) in the metal interlayer 750 acting as a coupling frame for contactless communication;

    [0298] 776: Operation of laser marking the rear overlay layer 770 with personalization data;

    [0299] compare 576 in FIG. 5B, and 676 in FIGS. 6A,B,C

    [0300] 724: Protective hard coat layer (5-10 μm)—a hard top-coat lamination film or a deposited coating (ink, varnish or a polymer) which can be laser marked or laser engraved;

    [0301] 726: A print layer (25 μm) which may comprise: (i) a digital, silk screen, lithographic or thermo-graphically layer of clear or colored ink, (ii) a baked-on-ink layer, (iii) a PVD or DLC coating, or (iv) a combination thereof, including an adhesion promoter or primer applied between the metal layer 730 and subsequent coatings;

    [0302] 730: Front face metal layer without a slit (“continuous”), which may have the print layer 726 disposed on it. A typical thickness for this metal layer may be 150 μm;

    [0303] 738: Adhesive layer (25 μm)—thermosetting epoxy—to attach the ferrite layer 742 with booster antenna circuit 744 to the rear side of the front face metal layer 730;

    [0304] 742: High permeability magnetic sheet shielding layer with a thickness of 50 μm or 100 μm which may compose of the following: calcium carbonate (CaCO.sub.3), silicon dioxide (SiO.sub.2), magnesium fluoride (MgF.sub.2), SiO2, chromium (Cr) and iron (Fe), to offset the effects of electromagnetic shielding caused by the front face metal layer 730 and having a booster antenna circuit 744 assembled to its face downside;

    [0305] 744: Booster antenna circuit assembled on a high permeability, low magnetic loss ferrite layer 742 comprising of a perimeter coil, a coupler coil and a set of trimming capacitors (not shown, are very small);

    [0306] The booster antenna circuit 744 is comparable to the CFA in FIGS. 5A,B, but has multiple turns (windings) and is a booster antenna (such as wire embedded, or etched). The CFA is a single turn (or winding). The booster antenna “circuit” is similar to a booster antenna as disclosed in U.S. Pat. No. 9,033,250, but has capacitors integrated into it.

    [0307] 748: Adhesive layer (25 μm)—thermosetting epoxy—spanning the entire width and length of the card body, being assembled to the rear side of the booster antenna circuit 744 and the metal interlayer 750 with a slit 720;

    [0308] 750: Metal interlayer or layers with a slit 720; The metal interlayer may be two metal layers with slits, separated by a dielectric (insulating) layer, which may be adhesive. The thickness of the metal interlayer may be 300-350 μm.

    [0309] A metal layer with slit and module opening may be referred to as a “coupling frame” (CF). See, e.g., U.S. Pat. Nos. 9,475,086; 9,798,968. And, two or more coupling frames may be stacked up, for example as in U.S. Pat. No. 9,836,684, which also discussed the need for reinforcing the metal layer at the position of the slit, which may be regarded as a mechanical defect.

    [0310] 758: Adhesive layer (25 μm)—thermosetting epoxy—to attach the metal interlayer 750 to the front side of the synthetic layer 760;

    [0311] 760: Transparent, translucent or white synthetic layer (e.g. PVC, PC, PETG), typically having a thickness of 150 μm;

    [0312] 762 primer;

    [0313] 764 ink (printed information (PI));

    [0314] The position of 762 and 764 may be interchangeable depending on the printing process.

    [0315] 770: Laser engravable overlay layer (PVC), typically having a thickness of 64 μm;

    [0316] 774: Magnetic stripe;

    [0317] Security elements (signature panel and hologram) are not shown.

    [0318] In this, and other embodiments disclosed herein, the card body may have a metal layer (or layers) which are substantially the full size of the card body, and the metal layer(s) have a module opening and may have a slit extending from a peripheral edge of the metal layer(s) to the module opening to facilitate the metal layer(s) to function as coupling frame(s) to permit contactless capability. In some embodiments, a metal layer may have a module opening and no slit.

    [0319] In this, and other embodiments disclosed herein, the construction of a card body may be shown, in an “exploded” perspective view, showing the various layers of the card body from the front (top) of the card body to the rear (bottom) of the card body. The constructions may be described from front-to-back, with some layers being described as being behind other layers.

    [0320] In FIG. 7A, the continuous metal layer 730 attenuates the electromagnetic field and so in order to passively power a transponder chip module by inductive coupling, shielding material 742 is required in the stack-up construction. An important aspect of the adhesive layer 738 between the metal layer 730 and the shielding layer 742 is the function as a dielectric spacer (738). The thicker the shielding layer, the greater the RF performance. The greater the distance between the metal layer 730 and the shielding layer 742, the greater is the frequency uplift of the system resonance frequency and the RF performance in terms of activation distance. The activation distance may be further enhanced by a coupling frame or discontinuous metal layer 750 positioned underneath the booster antenna circuit 744, separated by an adhesive layer 748. The coupling frame or discontinuous metal layer 750 also uplifts (raises) the system resonance frequency of the metal transaction card 700A. This (the function of the dielectric spacer) may be applicable to some of the other embodiments disclosed herein, whether or not explicitly disclosed.

    [0321] Also, the slit in the discontinuous metal layer 750 can be disguised with a primer, printed ink and a protective coating (ink, varnish or a polymer). This (disguising the slit in a discontinuous metal layer) may be applicable to some of the other embodiments disclosed herein, whether or not explicitly disclosed.

    [0322] Regulating the Card Body Weight while Increasing the Thickness of the Dielectric Spacer

    [0323] By way of an example in FIG. 7A, the weight of a metal transaction card is primarily determined by the combined weight of the continuous metal layer 730 and the discontinuous metal layer 750. By increasing the thickness of the dielectric spacer 738 between the continuous metal layer 730 and the shielding layer 742, and or increasing the thickness of the shielding layer 742 to enhance the RF performance, it is necessary to reduce the thickness of the metal layers which reduces the card body weight or to remove the synthetic layers from the rear side of the card body while maintaining the thickness of the metal layers. By removing the synthetic layers 758 (adhesive layer 25 μm) and 760 (transparent, translucent or white plastic layer 150 μm) and replacing them with a hard top coat lamination film ˜10 μm (laser reactive) with an outer adhesive layer which can accept printed information (PI) 764 ink, with the option to attach a laser engravable overlay layer 770 (PVC) typically having a thickness of 64 μm.

    [0324] In the following diagram (FIG. 7B), the metal interlayer 750 shown in FIG. 7A is relocated to be between the front face metal layer and the ferrite (shielding) layer with underlying booster antenna circuit.

    [0325] FIG. 7B is a diagram (exploded perspective view) of the stack-up construction of a dual interface metal face smartcard 700B with contactless tap to pay function on one side of the card body having a top metal interlayer 750 having a slit 720 to function as a coupling frame assembled underneath the front face metal layer 730 without a slit, and further comprising of a booster antenna circuit 744 mounted on a magnetic shielding layer 742 to operate in combination with the metal interlayer 750. The front face solid metal layer 730 is continuous metal layer with no discontinuity. The front face metal layer has an opening 712, the metal interlayer 750 has a slit (S) 720 and a module opening (MO) 714 to accept the insertion of a transponder chip module 710 with its module antenna inductively coupling with the slit 720 in the coupling frame 750 as well as with the coupler coil of the booster antenna 744. The metal interlayer 750 with slit may be replaced by a coupling frame antenna. The metal interlayer 750 may also not need to inductively couple with the module antenna, but rather take on the function as a discontinuous metal frame (DMF).

    [0326] The stack-up construction of the card body (CB) 700B (smartcard (SC) or transaction card (TC)) with a front face continuous metal layer without a discontinuity may comprise the following layers:

    [0327] 710: Transponder chip module (TCM) or inductive coupling chip module (ICM);

    [0328] 712: P1 Module opening (MO);

    [0329] 714: P2 Module opening (MO);

    [0330] 720: Slit (S) in the top metal interlayer 750 acting as a coupling frame for contactless communication;

    [0331] 776: Operation of laser marking the rear overlay layer with personalization data;

    [0332] compare 676 in FIGS. 6A,B,C

    [0333] 724: Protective hard coat layer (5-10 μm)—a hard top-coat lamination film or a deposited coating (ink, varnish or a polymer) which can be laser marked or laser engraved;

    [0334] 726: A print layer (25 μm) which may comprise of: (i) a digital, silk screen, lithographic or thermo-graphic layer of clear or colored ink, (ii) a baked-on-ink layer, (iii) a PVD or DLC coating, or (iv) a combination thereof, including an adhesion promoter or primer applied between the metal layer 730 and subsequent coatings;

    [0335] 730: Front face metal layer without a slit (continuous) which may have a print layer 726, typically the metal layer having a thickness of 150 μm;

    [0336] 738: Adhesive layer (25 μm)—thermosetting epoxy—to attach the metal interlayer 750 with slit 720 to the rear side of the front face metal layer 730;

    [0337] 750: Metal interlayer or layers with a slit 720 (300-350 μm); Note that in FIG. 7B, the discontinuous (with slit) metal layer (coupling frame) 750 is on top of the booster antenna circuit 744, rather than below it, as in FIG. 7A.

    [0338] 748: Adhesive layer (25 μm)—thermosetting epoxy—spanning the entire width and length of the card body, being assembled to the rear side of the metal interlayer 750 with a slit 720 and the top side of the ferrite layer 742;

    [0339] 742: High permeability magnetic sheet layer with a thickness of 50 μm or 100 μm which may compose of the following: calcium carbonate (CaCO.sub.3), silicon dioxide (SiO.sub.2), magnesium fluoride (MgF.sub.2), SiO2, chromium (Cr) and iron (Fe), to offset the effects of electromagnetic shielding caused by the front face metal layer 730, and having a booster antenna circuit 744 assembled to its bottom side;

    [0340] 744: Booster antenna circuit assembled on a high permeability, low magnetic loss ferrite layer 742 comprising of a perimeter coil, a coupler coil and a set of trimming capacitors;

    [0341] 758: Adhesive layer (25 μm)—thermosetting epoxy—to attach the booster antenna circuit 744 on the ferrite layer 742 to the front side of the synthetic layer 760;

    [0342] 760: Transparent, translucent or white synthetic layer (e.g. PVC, PC, PETG), typically having a thickness of 150 μm;

    [0343] 762 primer;

    [0344] 764 ink (printed information (PI));

    [0345] The position of 762 and 764 may be interchangeable depending on the printing process.

    [0346] 770: Laser engravable overlay layer (PVC), typically having a thickness of 64 μm;

    [0347] 774: Magnetic stripe;

    [0348] Security elements (signature panel and hologram) are not shown.

    [0349] So, in FIG. 7B, there is a continuous metal layer 730 with an opening and without a slit, under which is a discontinuous metal layer (or frame) 750 with slit and opening, under which is a ferrite shielding layer 742, below which is the booster antenna circuit 744.

    [0350] Although not shown, the discontinuous metal layer 750 (with slit) could have a portion protruding downward in the manner of the portion 632 of the layer 632 shown in FIG. 6B (and the protruding portion fits into the hole/opening 641 in the ferrite shielding layer 640 (in 7B, 742)

    [0351] An Overview of the Embodiments Shown in FIGS. 5A/B, 6A/B/C, 7A/B

    [0352] These figures show some examples of smartcards (or transaction cards) having ID-1 format, which are dual interface (contact and contactless).

    [0353] Some of the card body constructions may have a front metal layer (e.g., 530, 630, 730) having a module opening for accepting insertion of a transponder (or inductive) chip module having contact pads on its front surface for the contact interface, and an internal module antenna for inductive coupling to facilitate the contactless interface. This front metal layer does not have a slit, and may therefore be referred to as “continuous”. Because there is no slit in the front metal layer, the front metal layer impairs contactless functionality from the front of the card, and the card may be referred to as “one-sided”, meaning that its contactless functionality works only from the back side of the card.

    [0354] Some of the card body constructions may have a shielding layer (e.g., 540, 640, 742) disposed below the front metal layer. Most of the shielding layers are the same size (ID-1) as the card body.

    [0355] The FIG. 5A construction has a coupling frame antenna (CFA) disposed on a support layer (502) behind the shielding layer.

    [0356] The FIG. 5B construction has a coupling frame antenna (CFA) disposed on a support layer (550) behind the shielding layer.

    [0357] The FIG. 6A construction has a coupling frame (metal layer 650 with a slit 620) disposed behind the shielding layer.

    [0358] The FIG. 6B construction has a coupling frame (metal layer 650 with a slit 620) disposed behind the shielding layer.

    [0359] The FIG. 6C construction has a coupling frame (metal layer 650 with a slit 620) disposed behind the shielding layer, which is disposed around the periphery of the card.

    [0360] The shielding layer may have a hole 641 (FIG. 6B) or an oversize hole 643 (FIG. 6C) for accepting a protrusion from the overlying continuous metal layer.

    [0361] The FIG. 7A construction has a booster antenna circuit (744) disposed behind the shielding layer, and also has a coupling frame (metal layer 750 with a slit) disposed behind the booster antenna circuit.

    [0362] The FIG. 7B construction has a coupling frame (metal layer 750 with a slit) disposed behind the shielding layer, and also has a booster antenna circuit (744) disposed behind the coupling frame.

    [0363] FIGS. 5A/B, 6A/B/C and 7A/B include what may be called an “Amplifying Element” located in the stackup (construction) of the card body, to offset the attenuating effects of the front (continuous) metal layer (ML; 530, 630, 730). In FIGS. 5A/B, the amplifying element is realized as a coupling frame antenna (CFA) 507. In FIGS. 6A/B/C, the amplifying element is realized as a coupling frame (CF) 650. In FIGS. 7A/B, the amplifying element is realized as a booster antenna circuit (BAC) 744.

    [0364] FIG. 8A shows a metal card body with an opening to accept the implanting of an inductive coupling chip module and the corresponding dimensions thereof with a rear synthetic layer (laser engravable overlay) capturing the security elements (not shown), and ready for lamination to the metal layer.

    [0365] FIG. 8B shows a metal card body with the opening to accept the implanting of the inductive coupling chip module and the synthetic layer laminated to the metal layer. The opening may be oversized to allow a compound to be dispensed into the void. The compound may be a non-conductive medium or a ferromagnetic medium to concentrate magnetic flux lines around the inductive coupling chip module.

    [0366] FIG. 8C shows a metal card body with the opening filled with a compound and cured to a solid state. The compound may be partially or fully dispensed into the area.

    [0367] FIG. 8D shows a metal card body with the solid compound structure machined to have a recess area matching the shape and dimensions of the inductive coupling chip module. As an alternative method to mechanically milling the compound structure, the compound may be formed using an ultrasonic tool or hot stamp tool.

    [0368] The compound may be a UV curing resin such as Colorit®. Reference is made to https://www.heimerle-meule.com/products/coloritr/working-with-colorit/FIG. 8E is a side view of a transaction card embodying the invention showing a metal card body with an inductive coupling chip module implanted in the machined recessed area having interior walls composed of the compound structure. Pre-implanting, the compound structure has been milled or formed into shape.

    [0369] The Module Cavity

    [0370] A mechanically milled oversized module cavity in a metal transaction card (metal core or metal face) may be filled with a compound, allowed to cure to a harden state, and thereafter a pocket is milled in the solid compound to accept the outline and form of the module tape and the mold mass of a transponder chip module (aka an inductive coupling chip module (ICM)). The compound may be an epoxy resin such as Bisphenol, Novolac, Aliphatic, and Glycidylamine.

    [0371] The fill process may be a dispensing, encapsulation, injection molding, transfer molding or potting process.

    [0372] In creating the module cavity in a metal transaction card having a nominal thickness of 760 μm, there are two process steps in the CNC milling to form a stepped cavity. The first process step is to mill the P1 cavity which has a depth of 250 μm (to match the thickness of the glass epoxy tape 190 μm (module tape (MT)) and the hot-melt tape 60 μm (adhesive layer)) and has lateral dimensions which are slightly larger (typically 80 to 100 μm on all four sides) than the module tape having 6 or 8 contact pads. The second process step is to mill the P2 cavity to a depth of at least 580 μm which represents the overall thickness of the transponder chip module from the front contact pads to the rear edge of the mold mass. The shape of the cavity to accept the mold mass of the transponder chip module may be square having dimensions of 7 mm in the x and y axis.

    [0373] Whether the transaction card is a laminated metal core (plastic-metal-plastic) or a metal face (metal-plastic) smartcard with dual interface capability, there is always a plastic layer on the rear of the metal card body to house the magnetic stripe and the security elements (signature panel and hologram) which are hot stamped to the plastic surface. The plastic layer is usually an overlay layer having a thickness of 50 μm.

    [0374] In mechanically milling the stepped cavity from the front face to the rear face of the transaction card, the milling tool during CNC milling of the stepped cavity invariably reaches the rear overlay layer which is extremely thin and can be easily distorted or wrinkled if pressure is applied to the area of the module opening in the metal card body for which the rear overlay material covers and protects.

    [0375] Another process problem associated with the implanting of a transponder chip module is the adhesion of the glass epoxy tape with gold plated copper tracks on its face down side which form the module antenna, to the metal layer which acts as the coupling frame to facilitate contactless communication, using an adhesive tape applied to the module tape. The adhesion is hampered by the interface of the glass epoxy with another adhesive layer used to attach the plastic (printed layer) with the metal. The interface with poor adhesion results in a chip module that can easily pop out from the module pocket of the card body.

    [0376] After CNC milling the P1 and P2 cavities, a compound may used to fill the stepped cavity area, which can be regarded as a potting or encapsulation process. In a further step, a module pocket is milled out from the potting compound.

    [0377] The advantage of this process is two-fold. Firstly, the glass epoxy tape can be easily attached with the adhesive tape to the metal layer or a synthetic layer in the card body. Secondly the rear area of the module cavity is protected with the potting compound, thus preventing distortion of the overlay material.

    [0378] The milling of an oversized pocket, filling the pocket with a non-conductive compound, and then mechanically forming the compound to have well-defined dimensions to accept the form and shape of an electronic component can simplify the manufacturing of metal transaction cards with a biometric sensor or display. The mechanical forming may be milling, stamping, or any forming process using heat, cooling, pressure or vacuum. The compound may be formed in a solid, liquid or molten state. For example, the compound may be dispensed into the pocket and with a forming tool pressed into shape to accept the contours of an electronic component. The compound may also be formed using an ultrasonic tool.

    [0379] To further assist in the adhesion of the inductive coupling chip module with a backing adhesive layer or tape to a metal surface or a formed compound surface, the underlying card body substrate can be pre-heated using hot blowers, heating elements or infra light.

    [0380] The same potting procedure can be implemented to reinforce a slit (discontinuity) in a metal card body. The prior art suggests using a metal backing insert with a slit or a plastic backing insert, to stabilize a discontinuity in a metal card body.

    [0381] Recess/Filling

    [0382] A recess around the rear area of a discontinuity (slit) in a metal card body may be chemically etched at each card body site in a metal inlay format, such as 2×8 or 5×5 array of sites. At each recess area in the array of card body sites, a compound may be used to fill each recess, preferably with a compound which can withstand high temperatures such as those used in a paint bake process (400° F.).

    [0383] The chemical etching can create the recess. Additionally, trenches or gratings may be produced in the metal to support the adhesion of the compound. The compound may contain nanofibers to produce a composite structure.

    [0384] During singulation of a card body from a metal inlay, there is a risk of smearing of the metal around the area of the slit at the perimeter edge of the card body. This smearing is caused by ageing or dulling of the CNC milling tool over time. This smearing of the slit also occurs during milling of the module pocket where the slit terminates in the module opening. The prior art suggests creating slit termination holes (STH) at each card body site in the metal inlay where the slit reaches the module opening, but it is silent on the effects of smearing of the slit at the perimeter edge of the card body. This smearing of the metal results in electrical shorting of the slit, impairing the contactless functionality of the transaction card.

    [0385] Therefore, the slits in the metal layer or metal layers of the transaction card may terminate at the module opening with a shape in the form of a semi-circle “(” or delta “<”. In addition, the slit commencing at the perimeter edge of the card body may also be in the form of a semi-circle “(” or delta “<”, to avoid metal smearing of the slit when the milling tool ages with time.

    [0386] Disguising the presence of a discontinuity in a metal layer or a metal card body have been discussed above, in which an epoxy resin (one or two component) is used to fill the slit or slits, and thereafter in a paint bake process, the entire metal area is covered with a color and protected by a clear lacquer which gives the metal a gloss or satin finish. In another embodiment of the invention to protect the surface finish of the paint bake layer on the metal surface from scratches during the lamination of the rear plastic layers with security elements and graphic features to the metal layer, a hard coat layer is laminated to the exposed metal surface. This hard coat layer may be matt or gloss depending on the surface finish of the lamination plates. To engrave a deboss logo, a picosecond laser may be used to ablate the hard coat, lacquer, paint and metal layers.

    [0387] In producing a metal transaction card with a metal foil hologram, it is an embodiment of the invention to first laminate a hard coat layer to the metal surface, and thereafter to hot stamp the metal foil hologram to the hard coat layer. The prior art suggests hot stamping the metal foil hologram to a synthetic layer (overlay) and not to a hard coat layer laminated to the metal layer.

    [0388] FIG. 9A shows a slit 920 commencing at a perimeter edge of the metal card body 900A and terminating at the inductive coupling chip module 910, with the slit exhibiting a semi-circle opening shape at each end of the slit.

    [0389] FIG. 9B shows a slit 920 commencing at a perimeter edge of the metal card body 900B and terminating at the inductive coupling chip module 910, with the slit exhibiting a delta (triangular) opening shape at each end of the slit.

    [0390] The slit termination hole (STH) at the module opening may be disclosed in some prior art patents, but the technique disclosed herein goes one step further and creates an STH at the perimeter of the card body, which helps a lot.

    [0391] CNC Milling

    [0392] Typically, cards may be manufactured (laid up and laminated) in sheet form, each sheet having a plurality of cards, such as in a 5×5 array, and CNC (computer numerical control) machining may be used to singulate (separate) the finished cards from the sheet. Resulting burrs, particularly in the metal layers, may cause defects, such as electrical shorting of the slit. Hence, CNC machining of metal core, metal face or solid metal smartcards may be performed using cryogenic milling, such as in an environment of frozen carbon dioxide or liquid nitrogen.

    [0393] Some Additional Comments

    [0394] Some of the card embodiments disclosed herein may have two metal layers, separated by a dielectric coating or an insulating layer, rather than a single metal layer. The two metal layers may comprise different materials and may have different thicknesses than one another. For example, one of the metal layer may be stainless steel while the other metal layer may be titanium. In this manner, the “drop acoustics” of the metal card body may be improved, in that the card, when dropped or tapped (edgewise) on a hard surface, sounds like a solid metal card (making a ringing or tinkling sound), rather than like a plastic card (making a “thud”).

    [0395] Generally, in order for the smartcard to be “RFID-enabled” (able to interact “contactlessly”), each of the one or more metal layers should have a slit, or micro-slit. When there are two (or more) metal layers with slits in the stack-up, the slits in the metal layers should be offset from one another.

    [0396] Some Generic Characteristics

    [0397] The smartcards described herein may have the following generic characteristics: [0398] The card body may have dimensions similar to those of a credit card. ID-1 of the ISO/IEC 7810 standard defines cards as generally rectangular, measuring nominally 85.60 by 53.98 millimeters (3.37 in×2.13 in). [0399] A chip module (RFID, contact type, or dual interface) may be implanted in a recess (cavity, opening) in the card body. The recess may be a stepped recess having a first (upper, P1 portion) having a cavity depth of 250 μm, and a second (lower, P2 portion) having a cavity depth of (maximum) 600 μm. [0400] A contact-only or dual interface chip module will have contact pads exposed at a front surface of the card body. [0401] ISO 7816 specifies minimum and maximum thickness dimensions of a card body: [0402] Min 0.68 mm (680 μm) to Max 0.84 mm (840 μm) or Min 0.027 inch to Max 0.033 inch

    [0403] Generally, any dimensions set forth herein are approximate, and materials set forth herein are intended to be exemplary. Conventional abbreviations such as “cm” for centimeter”, “mm” for millimeter, “μm” for micron, and “nm” for nanometer may be used.

    [0404] The concept of modifying a metal element of an RFID-enabled device such as a smartcard to have a slit (S) to function as a coupling frame (CF) may be applied to other products which may have an antenna module (AM) or transponder chip module (TCM) integrated therewith, such as watches, wearable devices, and the like.

    [0405] Some of the features of some of the embodiments of RFID-enabled smartcards may be applicable to other RFID-enabled devices, such as smartcards having a different form factor (e.g., size), ID-000 (“mini-SIM” format of subscriber identity modules), keyfobs, payment objects, and non-secure NFC/RFID devices in any form factor

    [0406] The RFID-enabled cards (and other devices) disclosed herein may be passive devices, not having a battery and harvesting power from an external contactless reader (ISO 14443). However, some of the teachings presented herein may find applicability with cards having self-contained power sources, such as small batteries (lithium-ion batteries with high areal capacity electrodes) or supercapacitors.

    [0407] The transponder chip modules (TCM) disclosed herein may be contactless only, or dual-interface (contact and contactless) modules.

    [0408] In their various embodiments, the invention(s) described herein may relate to payment smartcards (metal, plastic or a combination thereof), electronic credentials, identity cards, loyalty cards, access control cards, and the like.

    [0409] While the invention(s) may have been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention(s), but rather as examples of some of the embodiments of the invention(s). Those skilled in the art may envision other possible variations, modifications, and implementations that are also within the scope of the invention(s), and claims, based on the disclosure(s) set forth herein.