| 摘要 |
<p>A security document (1), such as a banknote is formed from a sheet-like substrate (10) of clear plastics material with layers (13, 14, 15, 16) of opacifying ink applied to the surfaces (11, 12) of the substrate (10). The security document (1) includes a security device (20) which is at least partially obscured by the layers (13, 14) of opacifying ink on a first surface (11) of the substrate (10). The layers (15, 16) on the second surface (12) of the substrate (10) are applied in such a manner so as to leave a 'half-window' area uncovered by opacifying ink through which the security device (20) is visible from one side of the document (1). The security device (20) may extend transversely outside the half-window area and be visible in transmission, enabling a different contrasting effect to be observed from both sides of the document.</p> |
