Electronic article surveillance tag product and method of manufacturing same

• US 5,781,110 A
• Filed: 05/01/1996
• Issued: 07/14/1998
• Est. Priority Date: 05/01/1996
• Status: Expired due to Fees

• Current Assignee: Graphic Packaging International Incorporated
• Original Assignee: James River Paper Company, Inc.
• Inventors: Habeger, Charles C. Jr., Pollart, Kenneth A.
• Primary Examiner(s): Hofsass, Jeffery A.
• Assistant Examiner(s): Lee, Benjamin C.
• Application Number:
  US08/640,463
• Time in Patent Office: 804 Days
• Field of Search: 340/572, 340/825.54, 310/311, 343/895, 333/205, 29/832, 29/854
• US Class Current: 340/572.5
• CPC Class Codes: G08B 13/2414 using inductive tags
• CPC Class Codes: G08B 13/2437 Tag layered structure, processes for making layered tags
• CPC Class Codes: G08B 13/244 Tag manufacturing, e.g. continuous manufacturing processes
• CPC Class Codes: G08B 13/2442 Tag materials and material properties thereof, e.g. magnetic material details
• CPC Class Codes: H05K 1/162 incorporating printed capacitors
• CPC Class Codes: H05K 1/165 incorporating printed inductors
• CPC Class Codes: H05K 3/4644 by building the multilayer layer by layer, i.e. build-up multilayer circuits making via holes in the insulating layers H05K3/0011; special circuit boards as base or core whereon the multilayer is built H05K3/4602
• CPC Class Codes: Y10T 29/4913 Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49169 Assembling electrical component directly to terminal or elongated conductor

Abstract

An RF EAS tag includes a substrate with a conductive element positioned on a face surface thereof and having electrically inductive properties. A capacitive element is positioned on the face surface and has electrically capacitive properties wherein the inductive and capacitive elements are operably coupled together to form a resonant circuit which resonates when an electrical signal of a predetermined resonant frequency is applied to the tag. The capacitive element comprises a dielectric ink substance having a high dielectric constant for producing the desired resonant circuit on a single face surface of the substrate. An alternative tag comprises a substrate with a conductive layer positioned thereon and a gap formed in the conductive layer exposing a portion of the substrate. This forms a slotline waveguide shorted at both ends. A high dielectric constant ink substance is then deposited in the slot. This greatly reduces the wavelength in the waveguide allowing an RF frequency 1/2 wavelength resonant line to be made of a practical length.

Claims

1. An electronic article surveillance tag comprising:

a substrate having a face surface;

a first element positioned on the face surface and operable for having electrically inductive properties when an electrical signal is applied thereto, the first element having spaced portions;

a second element positioned on the face surface to contact said first element spaced portions and span therebetween, the contacting first element spaced portions and second element operable for having electrically capacitive properties when said electrical signal is applied thereto;

the first and second elements being operably coupled together to form a resonant circuit which resonates when an electrical signal of a predetermined resonant frequency is applied to the tag;

the second element comprising a dielectric ink substance on the substrate, the dielectric ink substance being characterized by a high dielectric constant for producing the desired resonant circuit on a single face surface of the substrate.

2. The electronic article surveillance tag of claim 1 further comprising a dielectric ink substance having a dielectric constant in the range of approximately 5,000 to 1,000,000.

3. The electronic article surveillance tag of claim 1 wherein the inductive and capacitive elements are operable for forming a resonant circuit that resonates at a predetermined resonant frequency in the range of approximately 7 to 10 MHz.

4. The electronic article surveillance tag of claim 1 wherein the substrate is one of plastic and paper.

5. The electronic article surveillance tag of claim 1 wherein said inductive element is generally planar, the inductive element being generally parallel to said substrate face surface.

6. The electronic article surveillance tag of claim 1 wherein the inductive element is spirally shaped and includes at least two adjacent intercoil turns, the dielectric ink substance of said capacitive element applied to the face surface between the adjacent intercoil turns for operably coupling the inductive and capacitive elements together.

7. The electronic article surveillance tag of claim 1 wherein the inductive element comprises a spiral conductor positioned on the face surface and having inductance properties.

8. The electronic article surveillance tag of claim 7 wherein the spiral conductor includes aluminum.

9. The electronic article surveillance tag of claim 7 wherein the spiral conductor has a circular shape.

10. The electronic article surveillance tag of claim 7 wherein the spiral conductor has a rectangular shape.

11. The electronic article surveillance tag of claim 1 wherein the dielectric ink substance includes flakes of a conductive material.

12. The electronic article surveillance tag of claim 11 wherein the conductive material is a metal.

13. The electronic article surveillance tag of claim 11 wherein the conductive material includes aluminum.

14. An electronic article surveillance tag comprising:

a substrate having a face surface;

a conductive layer positioned on the substrate face surface;

a gap formed in the conductive layer and exposing a portion of the substrate;

the gap and conductive layer operably forming a waveguide having an effective resonance condition such that the tag resonates when an electrical signal of a predetermined resonant frequency is applied thereto;

a dielectric ink substance positioned in at least a portion of the gap, the dielectric ink substance being characterized by a dielectric constant substantially higher than the dielectric constant of air for lowering the predetermined resonant frequency at which the tag resonates.

15. The electronic article surveillance tag of claim 14 wherein the gap comprises long, generally parallel conductive sides.

16. The electronic article surveillance tag of claim 14 wherein the gap is generally in the shape of a semi-circle.

17. The electronic article surveillance tag of claim 14 further comprising a non-conductive substrate area proximate at least one end of the gap.

18. The electronic article surveillance tag of claim 14 wherein the conductive layer is aluminum.

19. The electronic article surveillance tag of claim 14 wherein the substrate is one of plastic and paper.

20. The electronic article surveillance tag of claim 14 further comprising a dielectric ink substance having a dielectric constant in the range of approximately 5,000 to 1,000,000.

21. The electronic article surveillance tag of claim 14 wherein the dielectric ink substance produces resonance at a predetermined resonant frequency in the range of 7 to 10 MHz.

22. The electronic article surveillance tag of claim 14 wherein the dielectric ink substance includes flakes of a conductive material.

23. The electronic article surveillance tag of claim 22 wherein the conductive material is a metal.

24. The electronic article surveillance tag of claim 22 wherein the conductive material includes aluminum.

25. The electronic article surveillance tag of claim 14 wherein the gap has a generally spiral shape.

26. The electronic article surveillance tag of claim 25 wherein the spirally-shaped gap includes intercoil turns portions which are generally circular.

27. The electronic article surveillance tag of claim 26 wherein the spirally shaped gap includes intercoil turns portions which are generally rectangular.

28. An electronic article surveillance tag comprising:

a substrate having a face surface;

a dielectric pattern positioned on the substrate face surface;

the substrate and dielectric pattern operably forming a waveguide having an effective resonance condition such that the tag resonates when an electrical signal of a predetermined resonant frequency is applied thereto;

the dielectric pattern including a dielectric ink substance positioned on the substrate, the dielectric ink substance being characterized by a dielectric constant substantially higher than the dielectric constant of air for lowering the predetermined resonant frequency at which the tag resonates.

29. The electronic article surveillance tag of claim 28 wherein the dielectric pattern is generally in the shape of a semi-circle.

30. The electronic article surveillance tag of claim 28 wherein the substrate is one of plastic and paper.

31. The electronic article surveillance tag of claim 28 further comprising a dielectric ink substance having a dielectric constant in the range of approximately 5,000 to 1,000,000.

32. The electronic article surveillance tag of claim 28 wherein the dielectric ink substance includes flakes of a conductive material.

33. The electronic article surveillance tag of claim 32 wherein the conductive material is a metal.

34. The electronic article surveillance tag of claim 32 wherein the conductive material includes aluminum.

35. The electronic article surveillance tag of claim 28 wherein the dielectric pattern has a generally spiral shape.

36. The electronic article surveillance tag of claim 35 wherein spirally-shaped dielectric pattern includes intercoil turns portions which are generally circular.

37. The electronic article surveillance tag of claim 36 wherein the spirally-shaped dielectric pattern includes intercoil turns portions which are generally rectangular.

38. A method of manufacturing an article surveillance tag comprising:

providing a substrate having a face surface;

positioning an element having electrically inductive properties on the face surface, the element having spaced portions;

applying a dielectric ink substance, characterized by a high dielectric constant, onto the substrate to contact said element spaced portions and span therebetween and to form a capacitive element;

operably coupling the inductive and capacitive elements together for forming a resonant circuit which resonates when an electrical signal of a predetermined resonant frequency is applied to the tag.

39. The method of claim 38 further comprising forming the inductive element in the shape of a spiral conductor.

40. The method of claim 38 further comprising applying a dielectric ink substance having a dielectric constant in the range of approximately 5,000 to 1,000,000.

41. The method of claim 38 further comprising applying the dielectric ink substance to the face surface to contact a portion of the inductive element for coupling the elements together to form a resonant circuit.

42. The method of claim 38 further comprising forming the inductive element in the shape of a spiral conductor and applying the dielectric ink substance to the face surface between the adjacent intercoil turns for operably coupling the inductive and capacitive elements together.

43. A method of manufacturing an article surveillance tag comprising:

providing a substrate having a face surface;

positioning a conductive layer on the substrate face surface;

forming a gap in the conductive layer and exposing a portion of the substrate;

depositing a dielectric ink substance, characterized by a high dielectric constant, in a portion of the gap and forming a waveguide having an effective resonance condition such that the tag resonates when an electrical signal of a predetermined resonant frequency is applied thereto.

44. The method of claim 43 comprising forming the gap generally in the shape of a semi-circle.

45. The method of claim 43 further comprising applying a dielectric ink substance having a dielectric constant in the range of approximately 5,000 to 1,000,000.