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Flexographic presses are capable of producing good quality impressions
on many different substrates and is the least expensive and simplest of
the printing processes used for decorating and packaging printing. The use
of flexographic printing presses is on the rise. There are two primary
reasons for this: 1) it is a relatively simple operation; and 2) it is
easily adapted to the use of water-based inks. The widespread use of
water-based inks in flexographic printing means a large reduction in VOC
emission compared to the heatset web or gravure printing processes.
Publication flexography is used mainly in the production of newspaper,
comics, directories, newspaper inserts, and catalogs. Packaging
flexography is used for the production of folding cartons, labels, and
packaging materials. Large quantities of inks are used during normal runs
on flexographic presses; however, some printers are able to recycle a
majority of their spent inks and wash waters. Major chemicals used in
flexography include platemaking solution, water and solvent based inks,
and blanket/roller cleaning solvents.
Flexography is a form of rotary web letterpress, combining features of
both letterpress and rotogravure printing, using relief plates comprised
of flexible rubber or photopolymer plates and fast drying, low viscosity
solvent, water-based or UV curable inks fed from an "anilox" or
two roller inking system. The flexible (rubber or photopolymer) plates are
mounted onto the printing cylinder with double-faced adhesive. Plates are
sometimes backed with thin metal sheets and attached to the cylinder with
fastening straps for close register or ink alignment. This adds additional
cost to the plate and requires more makeready time, but when quality
printing is critical this type of plate can make the difference.
For more information see:
ABC's of Flexo for Folding Cartons. The article this links to is written by Mike Pfaff
and Jerry Henson and is copyright Flexographic Technical Association.
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