Printing Technologies for Packaging

Technology	Uses	Printing Mechanism	How to ID
Lithography	Folding cartons (cardboard boxes)	Uses water-receptive aluminum plates with oil-receptive photopolymer images areas. Requires oil-based ink, not suitable for many packaging substrates.	Rule out flexo and gravure, look for mottled solids.
Flexography	Board Labels Polyethylene bags	Photopolymer relief plate where image areas are raised above non-image background. Uses aqueous or oil-based ink.	White lines inside type
Gravure	Board Labels	Copper cylinders are engraved with a diamond stylus and then coated in chrome for durability.	Screened type
Digital	Board Labels	Electrostatic toner, used for short run labels, thin board, and prototypes.	Microscopic 3D toner

Lithography

Used for commercial printing (brochures, pamphlets, booklets) and publication printing (magazines, catalogs) when less than a million copies are required.
Requires oil-based ink with high degree of stickiness (tack) and resistance to flow (viscosity), along with aqueous fountain solution that must be monitored for pH and electrical conductivity.
Uncommon in packaging because of the high-tack, oil-based ink.
Can use soy-based ink for food and cosmetics containers.

Common for packaging substrates when low-tack, low viscosity water-based ink is required to avoid toxicity.
Can print a wide variety of substrates including all types of board, paper, plastic, and metal.
Quality has increased to rival lithography due to technical advances in plates and imaging.

Used when over 1 million copies are required.
Very high preparation costs due to expensive imaging and cylinder processing equipment.
Very high quality.