Print Process Descriptions: Printing Industry Overview: Gravure

Sheet-fed Gravure

Applications:

Sheet-fed gravure is used when very high quality impressions are required. Uses include the production of pictorial impressions for art books and posters and short runs of high quality packaging material such as cosmetics cartons. Sheet-fed gravure presses are also used for overall coating of products printed by sheet-fed offset to provide high brilliancy to the printed sheet and for the application of metallic inks that cannot be applied by the offset method. Additionally, sheet-fed gravure presses are used to produce proof copies prior to large rotogravure runs (GAA 1991). More information...

Process Overview

The sheet-fed gravure press differs from the web-fed press primarily in that paper is delivered to the press as pre-cut sheets instead of a continuous web. The printing mechanism in a typical sheet-fed gravure press consists of a gravure cylinder and an impression cylinder of the same size. The plate itself is a flexible metal sheet wrapped around a carrier cylinder equipped with a gripper to hold the plate in place during printing.

The offset gravure press is a standard gravure unit to which a rubber-covered transfer roller has been added. The image to be printed is transferred from the gravure printing cylinder to the roller. The transfer roller then prints the image on the substrate. More Information...

The transfer of the image from the cylinder to the roller is similar to the transfer method used in offset lithography. Offset gravure presses are used to print substrates with irregular surfaces such as wood veneer or decorated metal (GAA 1991).

In some printing processes, both sides of the web can be printed simultaneously. However, in gravure, printing of one side of the web must be completed before the other side can be printed. In practice, the web is printed on one side, rewound, flipped over, then printed on the other side. Some rotogravure presses are designed with a turning station that rotates the web 180 degrees. The web is then run through a parallel paper path with different cylinders that prints the opposite side of the paper. These presses are called double-ended presses.