Smart cards with metal layer(s) and methods of manufacture
Smartcards with metal layers manufactured according to various techniques disclosed herein. One or more metal layers of a smartcard stackup may be provided with slits overlapping at least a portion of a module antenna in an associated transponder chip module disposed in the smartcard so that the metal layer functions as a coupling frame. One or more metal layers may be pre-laminated with plastic layers to form a metal core or clad subassembly for a smartcard, and outer printed and/or overlay plastic layers may be laminated to the front and/or back of the metal core. Front and back overlays may be provided. Various constructions of and manufacturing techniques (including temperature, time, and pressure regimes for laminating) for smartcards are disclosed herein.
1. A radio-frequency identification (RFID) smartcard comprising:
a transponder chip module having an integrated circuit and an antenna to enable RFID communications;
a first metal layer having a module opening that receives the transponder chip module;
a second metal layer having a module opening that receives the transponder chip module; and
an electromagnetic shielding material disposed between the first metal layer and the second metal layer.
2. The RFID smartcard of claim 1 , further comprising a recess around a periphery of the second metal layer that receives the electromagnetic shielding material.
3. The RFID smartcard of claim 1 , wherein:
the first metal layer does not have a slit extending from the module opening to an outer edge of the first metal layer; and
the second metal layer has a slit extending from the module opening to an outer edge of the second metal layer.
4. The RFID smartcard of claim 1 , further comprising:
a capacitor positioned across a slit extending from the module opening of the second metal layer to an outer edge of the second metal layer; and
at least one of (i) a void in the electromagnetic shielding material to accommodate the capacitor, or (ii) a recess in the first metal layer to accommodate the capacitor.
5. The RFID smartcard of claim 1 , wherein the second metal layer surrounded by a frame.
6. The RFID smartcard of claim 5 , wherein at least a portion of the frame is thinner than the second metal layer to allow a protrusion of the electromagnetic shielding material around an outer edge of the second metal layer.
7. The RFID smartcard of claim 1 , further comprising an annulus around the module opening of the second metal layer, wherein at least a portion of the annulus is not covered by electromagnetic shielding material.
8. The RFID smartcard of claim 1 , wherein the second metal layer comprises a single turn closed loop antenna, and wherein the antenna of the transponder chip module overlaps an edge of the second metal layer.
9. The RFID smartcard of claim 1 , wherein the antenna of the transponder chip module overlaps the second metal layer.
10. A metal veneer smartcard comprising:
a dual interface transponder chip module having an antenna;
a first coupling frame comprising a first metal layer having a first slit;
a second coupling frame comprising a second metal layer having a second slit;
a module opening in the first metal layer, which, prior to lamination, is cut or sized to correspond to dimensions of the outer antenna portion of the transponder chip module;
a module opening in the second metal layer that receives the transponder chip module,
wherein there is an overlap between the second metal layer with the antenna of the transponder chip module.
11. The metal veneer smartcard of claim 10 , further comprising a PVC edge frame disposed on a reverse side of the second metal layer.
12. The metal veneer smartcard of claim 10 , further comprising an inner plastic layer laminated to a reverse side of the second metal layer.
13. The metal veneer smartcard of claim 10 , further comprising:
a PVC edge frame disposed on a reverse side of the second metal layer; and
an inner plastic layer laminated to a reverse side of the second metal layer,
wherein the two metal layers, PVC edge frame, and inner plastic layer are laminated together in one step to produce a subassembly.
14. The metal veneer smartcard of claim 10 , wherein the two metal layers are connected to each other, either directly or via at least one capacitor.
15. The metal veneer smartcard of claim 10 , wherein the second metal layer comprises a metal slug, at least some edges of which do not overlap the transponder chip module.