Method for Making Advanced Smart Cards With Integrated Electronics Using Isotropic Thermoset Adhesive Materials With High Quality Exterior Surfaces

• US 20080096326A1
• Filed: 03/23/2005
• Published: 04/24/2008
• Est. Priority Date: 03/23/2005
• Status: Active Grant

• Current Assignee: Cardxx Incorporated
• Original Assignee: Cardxx Incorporated
• Inventors: Reed, Paul
• Granted Patent: US 8,012,809 B2
• Time in Patent Office: Days
• US Class Current: 438/126
• CPC Class Codes: B29C 2045/14532 injecting between two sheets
• CPC Class Codes: B29C 45/1418 the inserts being deformed or preformed, e.g. by the injection pressure
• CPC Class Codes: B29C 45/14467 Joining articles or parts of a single article B29C45/14377, B29C45/14385, B29C45/14581, B29C45/14614 and B29C45/006 take precedence
• CPC Class Codes: B29C 45/14647 Making flat card-like articles with an incorporated IC or chip module, e.g. IC or chip cards
• CPC Class Codes: B29C 45/34 having venting means
• CPC Class Codes: G06K 19/073 Special arrangements for circuits, e.g. for protecting identification code in memory protection against unauthorised use of computer memory G06F12/14
• CPC Class Codes: G06K 19/077 Constructional details, e.g. mounting of circuits in the carrier
• CPC Class Codes: G06K 19/07724 the record carrier being at least partially made by a molding process molding in general B29C45/14
• CPC Class Codes: Y10T 29/49121 Beam lead frame or beam lead device
• CPC Class Codes: Y10T 29/49146 with encapsulating, e.g., potting, etc.
• CPC Class Codes: Y10T 29/49172 by molding of insulating material

Abstract

Advanced Smart Cards and similar form factors (e.g. documents, tags) having high quality external surfaces of Polyvinylchloride (PVC), Polycarbonate (PC), synthetic paper or other suitable material can be made with highly sophisticated electronic components (e.g. Integrated Circuit chips, batteries, microprocessors, Light Emitting Diodes, Liquid Crystal Displays, polymer dome switches, and antennae), integrated in the bottom layer of the card structure, through use of injection molded thermosetting or thermoplastic material that becomes the core layer of said Advanced Smart Cards. A lamination finishing process can provide a high quality lower surface, and the encapsulation of the electronic components in the thermosetting or thermoplastic material provides protection from the lamination heat and pressure.

Claims

1. A method for making an advanced smart card or similar device comprising a top layer, a core layer of thermoset polymeric material, and a bottom layer comprising an integrated electronics assembly mounted on a substrate, said method comprising:

(1) positioning the integrated electronics assembly mounted on a substrate in a bottom mold such that holes in the substrate are secured by mold registers in the bottom mold;

(2) positioning a top layer of synthetic paper (e.g. Teslin™

) or other suitable material in a top mold;

(3) closing the top mold to the bottom mold in a manner that creates a void space between the top layer and the integrated electronics assembly;

(4) injecting a thermosetting polymeric material into the void space at a temperature and pressure which are such that;

(a) the integrated electronics assembly mounted on a substrate is held in place by the mold registers;

the top layer of material is at least partially cold, low pressure molded into a cavity in the top mold;

(b) gases and excess polymeric material are driven out of the void space;

(c) the exposed areas of the integrated electronics assembly are encapsulated in the thermosetting polymeric material; and

(d) the thermosetting polymeric material bonds with both the top layer and the bottom layer to produce a unified precursor advanced smart card body;

(5) removing the unified precursor advanced smart card body from the top and bottom molds; and

(6) trimming the precursor advanced smart card to a desired dimension to produce a finished advanced smart card.

2. The method of claim 1, wherein the integrated electronics assembly mounted on a substrate has maximum dimensions of 54 mm high, 85.6 mm long, and 0.50 mm thick.

3. The method of claim 1, wherein the substrate is a printed circuit board.

4. The method of claim 1 wherein the inside surface of the top layer and the inside surface of the bottom layer are treated to facilitate the creation of a strong bond between the top layer and the thermosetting material and the bottom layer and the thermosetting material.

5. The method of claim 1 wherein the inside surface of the top layer and the inside surface of the bottom layer are treated by coating each with a bond promoting agent.

6. The method of claim 1 wherein the inside surface of the top layer and the inside surface of the bottom layer are treated by a corona discharge process.

7. The method of claim 1 wherein the thermosetting polymeric material is injected into the void space at a pressure between about ambient pressure and about 500 psi.

8. The method of claim 1 wherein the thermosetting polymeric material is injected into the void space at a pressure between about 80 and about 120 psi.

9. The method of claim 1 wherein the thermosetting polymeric material is injected into the void space at a temperature between about 56°

F. and about 100°

F.

10. The method of claim 1 wherein the thermosetting polymeric material is injected into the void space at a temperature between about 65°

F. and about 70°

F.

11. The method of claim 1 wherein a film bearing alphanumeric/graphic information is applied to the inside surface of the top layer.

12. The method of claim 1 wherein a layer of opacity preventing material is applied to the inside surface of the top layer.

13. The method of claim 1 wherein the integrated electronics assembly includes electronic components selected from the following group:

microprocessors, antennae, Integrated Circuit (IC) chips, batteries, Light Emitting Diodes (LED), Liquid Crystal Displays (LCD), polymer dome switches, resistors, sensors (such as fingerprint sensors), and capacitors.

14. The method of claim 1 wherein the top layer is formed from a flat sheet of polymeric material.

15. The method of claim 1 wherein the top layer is preformed with at least one card-forming cavity.

16. The method of claim 1 wherein the top layer is molded into a advanced smart card forming cavity of a top mold and the bottom layer is molded against a substantially flat surface of a bottom mold.

17. The method of claim 1 wherein the thermosetting polymeric material is a polyurethane.

18. The method of claim 1 wherein the thermosetting polymeric material is an epoxy.

19. The method of claim 1 wherein the thermosetting polymeric material is an unsaturated polyester.

20. The method of claim 1 wherein the void space is filled by a gate whose width is at least 25 percent of the width of an edge of a precursor Advanced Smart Card being filled by said gate.

21. A method for making an advanced smart card or similar device comprising a top layer, a core layer of thermoset polymeric material, and a bottom layer comprising an integrated electronics assembly mounted on a substrate, said method comprising:

(1) using an integrated electronics assembly mounted on a substrate, with maximum dimensions of 54 mm wide, 85.6 mm long, and 0.50 mm thick, and positioning the integrated electronics assembly mounted on a substrate in a bottom mold such that holes in the substrate are secured by mold registers in the bottom mold;

(2) positioning a top layer of synthetic paper (e.g. Teslin™

) or other suitable material in a top mold;

(3) closing the top mold to the bottom mold in a manner that creates a void space between the top layer and the integrated electronics assembly;

(4) injecting a thermosetting polymeric material into the void space at a temperature between 65°

F. and 70°

F. and pressure between 80 PSI and 120 PSI which are such that;

(a) the integrated electronics assembly mounted on a substrate is held in place by the mold registers;

(b) the top layer of material is at least partially cold, low pressure molded into a cavity in the top mold;

(c) gases and excess polymeric material are driven out of the void space;

(d) the exposed areas of the integrated electronics assembly are encapsulated in the thermosetting polymeric material; and

(e) the thermosetting polymeric material bonds with both the top layer and the bottom layer to produce a unified precursor advanced smart card body;

(5) removing the unified precursor advanced smart card body from the top and bottom molds; and

(6) trimming the precursor advanced smart card to a desired dimension to produce a finished advanced smart card.