| 摘要 |
<p>Security paper is produced by incorporating a thermoplastic material in the paper mass, and heating the thermoplastic material to melting pt. Used for prodn. of bank paper, travel tickets, certificates, etc. The security paper is difficult to copy, and difficult to split into separate layers, as the fibres are bonded by the thermoplastic material. Pref. material melts below 160 degrees C and is metallised.</p> |
