Outside of the printing industry, most people are only familiar with the inkjet or laser printers they use at home or in the office. These work for everyday purposes, but obviously aren’t a fit for large-scale printing or printing on other materials. What gets used, then? One major process still used today is called rotogravure printing, or simply gravure. Best suited for fast, long-run printing, gravure creates high-quality grayscale or color prints for numerous products from magazines and packaging to stamps and wallpaper.
How Gravure Printing Works
Gravure painting uses a cylinder engraved—via lasers, diamond tools or acid-etching—with an image to transfer ink to a printing medium. The engraving comprises a grid of tiny cells that vary in depth, and when the cylinder is immersed in an ink tray, these cells carry different amounts of ink. Printing substrate is fed into the press, where the cylinder transfers the image to it as it rolls, also refilling ink at the same time. To make sure that the image prints properly, a doctor blade scrapes the surface to remove ink from between cells; abrasion-resistant metal blades are usually employed here. For color prints, multiple cylinders each apply a separate ink color.
Applications of Gravure Printing
While creating engraved cylinders presents a significant upfront cost, a gravure press can not only rapidly produce prints of a desired image through continuous operation, it also allows for high quality continuous-tone prints. The gravure cells vary in depth and ink capacity to enable a wide range of color, and the right ink and substrate combination lets the cells flow together so the viewer sees a solid image instead of an array of dots.
Rotogravure printing is most valued for very high-volume runs, and the color quality makes it well-suited for magazines, catalogues, newspaper supplements and other media containing photos or art. Because the cylinders remain viable for millions of prints, gravure printing also has low per-print costs, so it’s useful for mass-producing labels and packaging.