WASH DESTRUCTIBLE RESONANT TAG

• US 20090058757A1
• Filed: 08/19/2008
• Published: 03/05/2009
• Est. Priority Date: 08/29/2007
• Status: Active Grant

• Current Assignee: CHECKPOINT SYSTEMS, INC. (CCL Industries Incorporated)
• Original Assignee: CHECKPOINT SYSTEMS, INC. (CCL Industries Incorporated)
• Inventors: Strauser, Seth, Iacono, Charles
• Granted Patent: US 7,839,352 B2
• Time in Patent Office: Days
• US Class Current: 343/878
• CPC Class Codes: G08B 13/2414 using inductive tags
• CPC Class Codes: G08B 13/242 Tag deactivation
• CPC Class Codes: G08B 13/2437 Tag layered structure, processes for making layered tags
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

A resonant tag for use with a radio-wave detection system for the prevention of shoplifting or the like, which has a coil and capacitor circuit formed on opposite sides of an extremely thin substrate of a biaxially-oriented polypropylene, with one of the capacitor plates formed on one side of the substrate and the coil and other capacitor plate formed on the other side of the substrate, and paper layers on both sides of the tag, whereby the circuit is destroyed when the tag is washed in water or dry cleaned.

Claims

1. A resonant tag resonating with a radio wave at a predetermined frequency, comprising:

a polypropylene film having a thickness of approximately 8 μ

m or less;

a first circuit comprising a first metal foil including a coil portion and a plate portion, which comprises a first plate of a capacitor, formed on one side of said polypropylene film;

a second circuit made of a second metal foil including a plate section which comprises a second plate of said capacitor, formed on the other side of said polypropylene film;

a first paper layer adhered to said first circuit side;

a second paper layer adhered to said second circuit side; and

wherein said both circuits comprise an LC circuit by being electrically connected.

2. The resonant tag of claim 1 wherein said polypropylene film comprises a biaxially oriented polypropylene film.

3. The resonant tag according to claim 2, wherein said resonant tag has an area of 750 mm² or less.

4. The resonant tag of claims 2 wherein the predetermined resonant frequency is 5 to 15 MHz.

5. The resonant tag of claim 1 wherein said first and second metal foils comprise aluminum.

6. The resonant tag of claim 1 wherein said metal foils and said polypropylene film are laminated to each other by a styrene-based or olefin-based adhesive.

7. The resonant tag of claim 1 wherein said paper layers are adhered to said first and second circuit sides with a water-based adhesive.

8. A method for producing a resonant tag that resonates with a radio wave at a predetermined frequency, comprising:

providing a polypropylene film having a thickness of approximately 8 μ

m or less;

applying a first adhesive to one side of said polypropylene film;

applying a first metal foil to said first adhesive;

applying a second adhesive to the other side of said polypropylene film;

applying a second metal foil to said second adhesive to form a laminate having a first and second foil sides;

feeding said laminate to an etching process to remove portions of said first and second foils to form an LC circuit; and

adhering a paper sheet to each of said first and second foil sides

9. The method of claim 8 wherein said first and second adhesives comprises a styrene-based or olefin-based adhesive.

10. The method of claim 8 wherein said polypropylene film comprises a biaxially-oriented polypropylene film.

11. The method of claim 8 wherein said resonant tag has an area of 750 mm² or less.

12. The method of claim 8 wherein the predetermined resonant frequency is 5 to 15 MHz.

13. The method of claim 8 wherein said first and second metal foils comprise aluminum.

14. The method of claim 8 wherein said paper sheets are adhered to said first and second foil sides with a water-based adhesive.

15. A method for producing a resonant tag that resonates with a radio wave at a predetermined frequency, comprising:

providing a polypropylene film having a thickness of approximately 8 μ

m or less;

applying a first adhesive to one side of a first metal foil;

applying a second adhesive to one side of a second metal foil;

applying said first metal foil with said first adhesive and said second metal foil with said second adhesive to respective sides of a polypropylene film to form a laminate having first and second foil sides;

feeding said laminate to an etching process to remove portions of said first and second foils to form an LC circuit; and

adhering a paper sheet to each of said first and second foil sides.

16. The method of claim 15 wherein said first and second adhesives may comprise a styrene-based or olefin-based adhesive.

17. The method of claim 15 wherein said polypropylene film comprises a biaxially-oriented polypropylene film.

18. The method of claim 15 wherein said resonant tag has an area of 750 mm² or less.

19. The method of claim 15 wherein the predetermined resonant frequency is 5 to 15 MHz.

20. The method of claim 15 wherein said first and second metal foils comprise aluminum.