| 摘要 |
<p>There is provided with an indicator 1 for confirming data erasure to be placed in a magnetic field with a recording medium in placing the recording medium in the magnetic field so as to erase data recorded in the medium, including a displaying part 2 whose displaying status changes upon being placed in a magnetic field of a predetermined strength or more. The indicator 1 mainly consists of a transparent film layer 5, a core layer 6, and a magnetic body layer 7, which are adhesively bonded. The core layer 6 has a cavity 11 encapsulating magnetic particles 12. The magnetic particles 12 freely move within the cavity 11.</p> |
