Printing technique whereby the image to be printed is etched or engraved in the surface of a printing plate. First, a thick and highly pigmented ink is applied to the printing plate, then the non-printing (non-recessed) areas of the surface are wiped clear of ink. Finally, the ink that remains in the engraved parts of the printing plate (the image to be printed) is transferred to the substrate under high pressure. The pressure forces the substrate into the recessed areas of the printing plate, thereby producing a raised tactile relief which can be recognized under oblique light. The characteristic of intaglio printing is also suitable for the effect of latent image.
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