Contact-free security or identification tag

摘要

A contact-free security or identification tag, provided with an electrical circuit, has a pyrotechnic mixt. located near at least one connection of the circuit so that the connection is broken by combustion of the mixt. when ignited, the electrical properties of the circuit being altered by the connection breakage. Pref. the pyrotechnic material consists of one or more of a Pb3O4/Si/Te/Fe2O3 mixt., a PbCrO4/Zr mixt., a Pb3O4/Si/KNO3 mixt., a Pb3O4/Si mixt. and/or a mixt. with similar properties. Also claimed are (i) an inactivating and/or coding system provided with the above tag and with an electromagnetic field-emitting unit for igniting the pyrotechnic mixt.; and (ii) an electrical circuit for use in the above tag.