| 摘要 |
There is described a combined printing press (10) for the production of security documents, in particular banknotes, comprising a screen printing group (3) and a numbering group (4) adapted to process printed substrates in the form of individual sheets or successive portions of a continuous web. The screen printing group(3)is located upstream of the numbering group (4) and comprises at least one screen printing unit (32-33) designed to print a pattern of optically-variable ink, which optically-variable ink contains flakes that can be oriented by means of a magnetic field. The screen printing group further comprises a magnetic unit (36) located downstream of the screen printing unit (32-33), which magnetic unit (36) is designed to magnetically induce an optically-variable effect in the pattern of optically-variable ink applied by the screen printing unit (32-33) prior to drying/curing of the optically-variable ink. The screen printing group (3) further comprises at least one drying/curing unit (37) designed to dry/cure the pattern of optically-variable ink in which the optically-variable effect has been induced by the magnetic unit(36), prior to transfer of the printed substrates to the numbering group (4). |
