Flexography is a relief printing process. The image sits raised on a flexible plate, ink is metered onto that raised area, and the plate presses it onto the substrate as the board passes underneath. It is the workhorse of corrugated packaging because it prints well onto an uneven, absorbent surface at speed, which most other processes do not.
How the ink gets onto the board
Three parts do the work:
- The plate. A flexible polymer plate with the image standing proud of the base. One plate per colour, per design.
- The anilox roller. An engraved roller covered in tiny cells that hold a controlled volume of ink. It is the part that decides how much ink reaches the plate, and it is why flexo ink films are consistent across a long run.
- The impression. The board passes between the plate cylinder and an impression roller. On corrugated the pressure has to be light, because pressing too hard crushes the flutes and leaves a washboard mark down the panel.
What flexo prints well, and what it does not
| Artwork | Flexo result |
|---|---|
| Solid brand colours and bold logos | Excellent, the process is built for it |
| Line art, text, barcodes, icons | Good, with sensible minimum line weights |
| Large flat solids | Good, though very heavy coverage needs care on kraft |
| Photographic images and subtle gradients | Limited. Litho lamination or digital is the better route |
| Fine reversed-out small type | Risky, because ink spreads slightly and can fill the counters |
Plates, and why the count matters
Because there is one plate per colour, the number of colours in your artwork is a direct cost and complexity driver in normal industry practice: more plates, more setup, more registration to control. Design with that in mind and a two or three colour flexo job can look far richer than the plate count suggests, particularly on a kraft liner where the board colour does some of the work. On iBox orders the plates themselves are included, along with the die, so the decision is about the look and the run length rather than about a setup charge. Our page on plate charges explains what that normally costs elsewhere and why.
Flexo against the alternatives
Digital printing skips plates entirely, which suits short runs, frequent artwork changes and multiple versions of one box. Litho lamination prints a sheet on an offset press and laminates it to the board, which gives photographic quality at the cost of an extra process step. Flexo sits in the middle and wins on longer runs of straightforward artwork printed straight onto corrugated. For the head-to-head, see digital against offset packaging printing.
What to send us
Vector artwork wherever possible, with fonts outlined, colours specified as spot references rather than described in words, and a clear note of which panel is which. We will return a digital proof before anything prints, which is included on every order, and that proof is the moment to check colour breaks and small type rather than after the run.
Ordering
Minimum order is 100 boxes, with pricing from about $0.48 per unit at bulk volumes confirmed on your written quote. Design support and US shipping are included. Three production lanes are available: rush with expedited production and air freight, standard on air, and cost saver by sea, from about 7 business days, plus 2 to 5 for delivery. We print at West Chicago and at Guangzhou.
Send your artwork and the box style through the quote form and we will tell you which process suits the job.
