In relief printing, the reverse reading image is raised above the non-printing area on the plate. In flexo, ink is transferred to the image areas of the plate by using an anilox roll. An anilox roll is a gravure cylinder which has tiny cells engraved all over its surface. These cells pick up the liquid ink from the ink well, and the excess ink is wiped away by a doctor blade. This way, a very controlled amount of ink is transferred onto the raised surface of the flexible plate. Then, the plate prints directly onto the substrate.
Each color is printed and cured before the next color station, so this process works very well for printing four-color process artwork. Flexo printing is very fast once the job is set up on press, and printing is consistent throughout the run. Print quality is very high because of the amount of detail the plates can hold and because the substrate is printed in a flat state roll to roll.
Berry Plastics uses flexo printing for laminate tubes and some pressure sensitive labels. The printing press has 10 stations. A protective varnish is recommended for all jobs, so artwork needs to be nine colors or less. Berry can create new art, coordinate existing art and print in-house using this process.