| 摘要 |
<p>PURPOSE:To obtain a card difficult to forge and provided with a forgery preventing means capable of simply confirming genuineness by forming a light pervious coating layer containing a powder showing electrooptical Pockels effect or electrooptical Kerr effect and constituting the powder of oxide represented by a specific compositional formula. CONSTITUTION:A light pervious coating layer 3 containing a powder showing electrooptical Pockels effect or electrooptical Kerr effect and a color sample layer 4 are embedded in a part of a card substrate 1 in the state held between transparent protective layers 5a, 5b. Further, a magnetic stripe 2 is provided on the card substrate. The electrooptical layer is formed by patterning ink prepared by kneading the powder of oxide having a composition represented by (Pb1-xLax) (Zr1-yTiy)1-x/4O3 (0<=x<=0.3, 0.3<=y<=1.0). Further, the genuineness of a card can be easily confirmed by comparing the color sample layer 4 provided around the electrooptical layer 3 with color density. By this method, an extremely safe forgery preventing means can be provided.</p> |
