Rotogravure (roto or gravure for short) is a type of intaglio printing process, which involves engraving the image onto an image carrier. In rotogravure printing, the image is engraved onto a cylinder because, like offset printing and flexography, it uses a rotary printing press.
In direct rotogravure printing, the ink is applied directly to the cylinder and from the cylinder it is transferred to the substrate. One printing unit consists of the following components:
Ameri-Seal presently prints up to
ten (10) colors on this computerized
Metal Etched Cylinders
are used to create designs
for meticulous print quality.
solvent based inks which
Printing registration is
and is continuously monitored
throughout print run.
The first step of Gravure is to create the cylinder with the engraved images that need to be printed: the engraving process will create on the cylinder surface the cells that will contain the ink in order to transfer it to the Shrink Film. Since the amount of ink contained in the cells corresponds to different colour intensities on Shrink Film, the dimensions of the cells must be carefully set: deeper or larger cells will produce more intense colours whereas smaller cells will produce less intense ones. There are three methods of photoengraving that have been used for engraving of rotogravure cylinders, where the cell open size or the depth of cells can be uniform or variable. Rotogravure cylinders are usually made of steel and plated with copper, though other materials, e.g. ceramics can also be used. The desired pattern is achieved by engraving with a laser or a diamond tool, or by chemical etching.
The rotogravure printing process is the most popular printing process used in flexible-packaging manufacturing, because of its ability to print on thin film such as PETg or PVC, which come in a wide range of thicknesses, commonly 10 to 76 micrometers. Other appreciated features include:
Shortcomings of the gravure printing process include: