Printing Methods – Gravure
Rotogravure is an intaglio process meaning engraved or carved. The impressions are achieved by the transfer of ink from cells or depressions of varying depths, etched into the print cylinder to a web of paper at high speeds.
The process of printing involves coating the etched cylinder into an enclosed fountain or trough of ink and the etched cells are filled with ink. While the cells fi ll with ink, the sur-face of the cylinder (non-image area) also becomes coated with ink. This non-wanted ink is removed by a doctor blade or knife which wipes all of the surface ink from the cylinder. The printing cylinder comes in contact with the paper and the ink which remains in the cells is transferred to the paper.
High cylinder cost generally limits gravure to run lengths of over 1 million impressions, thus, gravure is a long run process. Gravure presses are also much wider than other printing type presses. Unlike Letterpress or Offset, the ink used is very fluid and is usu-ally solvent based which in today’s environment is undesirable.
Typical printed products would include packaging, catalogs, Sunday newspaper inserts (K-Mart, Parade Magazine, National Geographic, etc.)