EAS tag with magnetically structured control element

• US 4,935,724 A
• Filed: 07/27/1989
• Issued: 06/19/1990
• Est. Priority Date: 07/27/1988
• Status: Expired due to Term

• Current Assignee: Central Research Fund Limited
• Original Assignee: Thorn EMI Plc (Universal Music Group NV)
• Inventors: Smith, Andrew L.
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US07/385,861
• Time in Patent Office: 327 Days
• Field of Search: 340/551, 340/572
• US Class Current: 340/551
• CPC Class Codes: G06K 19/02 characterised by the selection of materials, e.g. to avoid wear during transport through the machine
• CPC Class Codes: G06K 19/06187 with magnetically detectable marking
• CPC Class Codes: G08B 13/2411 Tag deactivation
• CPC Class Codes: G08B 13/2417 having a radio frequency identification chip
• CPC Class Codes: G08B 13/2437 Tag layered structure, processes for making layered tags
• CPC Class Codes: G08B 13/2442 Tag materials and material properties thereof, e.g. magnetic material details

Abstract

A tag 2 for use in an electronic article surveillance system comprises a magnetically structured component 4 in close proximity to a striplike element 6 of magnetically soft material. The component 4 includes magnetic particles 8 orientated into particular directions in regions 10, 12, preferably at ±45° relative to the longitudinal axis of the tag.

The tag 2 can be deactivated by longitudinal wiping with a deactivator providing a magnetic field corresponding to the angle of orientation of the particles 8. Deactivation is, therefore, straightforward for a check out operator but not for a potential thief.

The orientated particles 8 can be used to define an interpretable code enabling product inventory with deactivation.

Claims

1. A tag for use in an electromagnetic identification system comprising an element of magnetically soft material and, in sufficiently close magnetic communication therewith for permitting local magnetic polarisation of the element, a magnetically structured component comprising, in a first region thereof, magnetic particles having their magnetic axes orientated in a first direction, and in a further region thereof, magnetic particles having their magnetic axes not generally orientated in any direction or orientated in a further direction.

2. A tag according to claim 1 wherein the axes of the magnetic particles in the first region are orientated at an angle of substantially 90°

with respect to the axes of the magnetic particles in the further region.

3. A tag according to claim 1 wherein the magnetically structured component is of strip form and the magnetic axes of the magnetic particles in the first and or further regions are orientated in a direction other than longitudinally of the strip.

4. A tag according to claim 3 wherein the magnetic axes of the magnetic particles in the first and or further regions are orientated at an angle of substantially 45°

to the longitudinal axis of the strip.

5. A tag according to claim 1 wherein the magnetic particles in the first and or further regions are arranged to define an interpretable code.

6. A tag according to claim 1 wherein the magnetically structured component is arranged to overlie the element of magnetically soft material.

7. A tag according to claim 1 wherein the magnetic particles comprise acicular particles.