DTP prepress – preparing files for flexographic printing

DTP prepress means preparing your design so the printer can run it without corrections, delays or surprises. At Poligraf PRO we check and prepare files for flexographic printing of labels and packaging – from colours and bleed, through die lines, to barcodes – and then pass them on to a verified printing house.

What does DTP for flexo involve?

Flexographic printing has its own specifics: higher dot gain than offset or digital printing, limits on minimum line thickness and text size, and strict die-line requirements. A file that looks right on screen is not always ready for print. That is why we analyse every design individually and, where needed, propose technical optimisations for your approval.

What we check and prepare

• File format and quality – ideally a closed PDF or an editable AI file; fonts embedded or converted to outlines, bitmap images at 300 dpi.
• Colours – CMYK colour space, Pantone spot colours clearly labelled; RGB and Lab elements are converted to CMYK. We print up to 8–10 colours (depending on the press).
• Bleed and safe area – 1 mm bleed on each side, safe print area at least 1.5 mm from the die-cut edge.
• Fine elements – minimum line thickness 0.15 mm, minimum font size 4 pt (5 pt when reversed out); small text and codes ideally in one colour.
• Die line – marked with a separate spot colour, sharp corners rounded.
• EAN barcodes – minimum width 37.29 mm, high contrast (ideally one colour on a white background).
• Finishing – white underprint, spot varnish, cold foil and lamination as separate layers; UV varnish mask in 100% K.
• Flexo specifics – tonal gradients starting at a minimum of 2–3% coverage; where the printer offers it, we recommend flat top dot technology.

How it works

1. You send your files – up to 10 MB by e-mail, larger via WeTransfer, Dropbox or Google Drive; ideally with a JPG/PDF preview.
2. We check them free of charge – a basic technical check is included.
3. You receive a digital proof (PDF) – you have 48 hours to approve it or send comments (unless agreed otherwise).
4. After your “Approved for print”, the files go into production.

Full requirements are in our Guidelines for preparing files for print (PDF).

Why use a print broker for DTP

File errors are the most common cause of delays and extra costs in label production. Because we work with many printing houses, we know the requirements of specific presses and prepare the file for the one that best suits your job. DTP is easy to combine with CTP plate imaging and print management – then one contact person handles the whole process.

Frequently asked questions

Which file formats do you accept?

We recommend a closed PDF or an editable AI (Adobe Illustrator) file. PSD with layers preserved is acceptable when further editing is needed. We do not accept files from word processors, spreadsheets or presentation software.

Is the file check free?

Yes, the basic technical file check is free of charge. Additional DTP work is quoted individually.

How long do I have to approve the proof?

48 hours from receiving the digital proof, unless agreed otherwise. No response within that time counts as tacit approval.

What bleed and safety margin should a label have?

1 mm bleed on each side and a safe print area at least 1.5 mm from the die-cut edge.