OFFSET PRINTING VS. DIGITAL PRINTING
The offset lithography printing process follows the simple principle that ink and water do not mix. In this process, image information (text and art) is placed on thin metal plates dampened by ink and water on rollers. The water goes toward the non-image area, and the oil-based ink adheres to the image area. The inked area is then transferred to a blanket (rubber cylinder) and then onto the substrate while it passes around the cylinder.
The technique is “offset” because, unlike digital printing, the image does not transfer directly from the printing plates to the substrate but instead is transferred first to an intermediary surface.