SAFE THREAD, AND APPARATUS AND METHOD FOR JUDGING GENUINENESS

摘要

PROBLEM TO BE SOLVED: To provide a safe thread for preventing the mistake of reading of magnetic data caused by the relative displacement between the safe thread and a printed product. SOLUTION: This safe thread having a magnetic layer 4 and an electroconductive layer 5 on a substrate 3 is obtained by forming an electroconductive part having a relatively strong micro wave-detecting voltage in the electroconductive layer 5, and arranging the position of the electroconductive part having the relatively strong micro wave-detecting voltage, and the position of the magnetic data recorded on the magnetic layer 4 so as to form a prescribed position relation.