| 摘要 |
<p>PURPOSE:To enable a user to easily recognize that a card almost comes into a use limit by a method wherein in the card provided with a first recording layer in which pixel information is recorded and erased by heating, a second recording layer which changes in color from a first color to a second color by heating is provided. CONSTITUTION:In a card 21, a metallized thin film 23 and a magnetic recording layer 8 are laminated on one surface of a substrate 22 of a transparent polyethylene terephthalate; and a first thermally color-changing layer 24 coming into a transparent state or an opaque state by heat, a red colored layer 25, a second thermally color- changing layer 26 coming into a transparent state or an opaque state by heat, and a protective layer 27 are provided on the other surface of the substrate 22. In the card 21, a balance operated in a second heat roller heating means 36 is compared with a predetermined balance value in a last stage. If it is less than the predetermined value, a heat roller preset to the transparent temp. of the thermally color-changing layer as the second indication layer is brought into contact with the second indication layer. This operation makes the thermally color-changing layer transparent. The color of the colored layer can be seen through the thermally color-changing layer. The second indication layer is indicated with a change in color as shown by an area 50.</p> |
