What is flexo printing.
Flexo is a printing method that uses a flexible relief plate to print paper and film on the reel, fast and at low cost. It prints our SOS, food grade and compostable bags. This page explains how it works, what it does well, and where its limits are.
The short answerFlexographic printing, or flexo, prints from a flexible plate with the image raised on its surface. An anilox roll lays an even film of ink on the plate, and the plate prints onto paper or film. The ink dries fast, by evaporation.
How flexo works
The plate is rubber or photopolymer, with the image standing up in relief. It wraps around a cylinder and turns against the paper or film as it runs past.
The anilox roll is engraved with fine cells, so it hands the plate the same amount of ink on every turn. That keeps the colour even across a long run.
Flexo prints on paper, plastic film, foil and corrugated board.
Flexo on paper bags
On a counter bag, flexo prints the paper on the reel before the bag is formed. The printed reel is then made into bags by machine.
Plates cost less than gravure cylinders, and solid colours print cleanly at volume. Flexo is not the method for photographs. Each colour needs its own plate.
| Bag | Flexo colours | Minimum order |
|---|---|---|
| SOS paper bag | Up to 4 | 5,000 |
| Food grade bag | Up to 4 | 10,000 |
| Compostable carrier bag | Up to 2 | 10,000 |
Flexo and gravure
Both print from the reel. Flexo prints from a raised plate, gravure from cells engraved into a metal cylinder. Gravure costs more to set up and holds a wider range of tones, and our pouches are printed by it.
More in What is gravure printing, and every method we use in How custom bags are printed.
Questions
What is flexographic printing used for?
Packaging printed in long runs: paper bags, corrugated boxes, envelopes and plastic film.
What is the difference between flexo and offset?
Flexo prints from a flexible raised plate. Offset litho transfers ink from a plate to a rubber blanket and then to the paper, and it holds finer detail such as photographs.
How many colours can flexo print on a bag?
Up to four on our SOS and food grade bags, and up to two on compostable film. Each colour needs its own plate.
Can flexo print photographs?
Not well on a paper bag. For a photograph on a bag, laminated paper printed by offset litho is the better route.
Written by the Bag Bureau production team. Last updated October 2026.