Offset is an indirect printing process in which text or image are transferred on to a cylinder covered with a rubber blanket and from there printed to the substrate. Offset printing relies on the principle of mutual repulsion of water and fat; characterized by even inking and precise edge limits. The printing and non-printing areas lie in the same plane of the printing plate. In security printing, another indirect printing process, indirect letterpress (sometimes also called dry offset) printing is widely used. Here the text or image is transferred from a letterpress printing plate to the rubber blanket. The result is very similar to “wet offset” (the characteristic features of letterpress printing are not always to be seen).
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