Marker for use in a magnetic anti-theft security system and method for making same

US6166636A · kind A · utility

Assignee

• Vacuumschmelze GmbH & Co. KG · DE

Inventors

• Matthias Herget · Bruchköbel, DE
• Ottmar Roth · Ortenburg, DE

Key dates

• Filing date: May 17, 1999
• Grant date: Dec 26, 2000
• Expiry date: May 17, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G08B13/2442
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A marker for employment in a magnetic anti-theft security system is composed of an oblong alarm strip of an amorphous ferromagnetic alloy and at least one activation strip applied onto the alarm strip and composed of a semi-hard magnetic alloy. One or more spatially separated regions that are composed of a non-magnetic phase are introduced into the activation strip with a thermal treatment. The semi-hard magnetic alloy has a coercive force H.sub.c of 15 through 100 A/cm and a remanence B.sub.r of at least 0.8 T.