Packaging Artwork File Prep: Bleed, Dielines and Specs

A print-ready design file and a finished, well-cut pack are not the same thing, and the gap between them is where most packaging reprints happen. A logo that looked sharp on screen turns soft once enlarged on a paper tag; a background colour that stopped exactly at the trim line leaves a thin white edge after cutting; a brand colour built in CMYK drifts slightly from the last print run. None of this is a design problem — it is a file-prep problem, and it is entirely avoidable once the basics of bleed, dielines and print specs are treated as part of the design process rather than an afterthought at the printer.

Start from the dieline, not the finished artwork

Every printed pack — a string-and-tag envelope, an outer carton, a dried-fruit pouch — is built from a dieline: a technical template marking the cut lines, fold lines and seal areas specific to that format and that press. Designing straight to a finished-size rectangle skips all of this, and the result is artwork that looks correct on screen but does not account for where the pack actually folds or seals. Requesting the real dieline from the co-packer or printer before opening a design file is the single step that prevents the most rework later.

Bleed exists because cutting is never perfectly precise

Bleed is the small margin of extra colour or image that extends past the trim line, and it exists because no cutting process, however well calibrated, lands in exactly the same place on every unit of a print run. Any background, pattern or photo that reaches the edge of the pack needs to extend into that bleed area; anything that stops precisely at the trim line risks a visible unprinted sliver the moment the cut shifts even slightly. The exact bleed measurement depends on the substrate and the printer's own equipment, which is another reason the dieline should come from the printer rather than an assumption carried over from a different job.

Safe margins matter more on small formats

A tea bag tag or an envelope has very little printable surface compared with an outer carton, so the same small cutting or folding variance that a carton easily absorbs can push text straight into a seal line or a trim edge on a smaller pack. Keeping product names, barcodes and any mandatory text inside a proper safe margin — pulled back from every cut and fold line, not just the outer edge — is what keeps a small pack legible after production rather than only on screen. This is also where grammage and format decisions feed back into the artwork: a bag sized for roughly 1.5 to 3 grams of blend, for example, has a genuinely tight printable area, and the safe margin has to be respected accordingly.

Choosing between CMYK and Pantone

Process colour, CMYK, reproduces photography and general multi-colour artwork well and is the default for most of a pack's design. A brand colour that has to stay identical across every reprint — a logo, a flavour-coding stripe used across a whole tea range — is safer specified as a named Pantone spot colour rather than a CMYK build, because a CMYK approximation can shift slightly between print runs and between different presses. Many packs mix both, using CMYK for imagery and a Pantone spot for the fixed brand elements; what matters is that the colour break is stated explicitly in the file rather than left for the printer to guess.

Resolution, fonts and the details that get missed

Every raster image and logo needs to be built or placed at 300 dpi at its actual print size, not scaled up from a smaller web asset, since anything pulled from a website is almost always too low resolution once enlarged onto a physical tag. Fonts should be embedded or outlined so text does not reflow or substitute on another machine, and the file should carry the colour profile the printer expects rather than leaving colour management to chance. These are small technical checks, but they are also the specific details that most often send a first proof back for correction.

Get a physical proof before the plates are cut

The final step is exporting a press-ready PDF with bleed and crop marks included, then requesting an actual proof — printed on the real bag, tag or carton stock — before signing off a full production run. A screen preview cannot show how ink sits on a paper tag or how a colour reads on a coated pouch versus an uncoated one, and that is exactly the gap a physical proof is meant to close. TeraVella reviews artwork fit against the dieline for private label tea bag, envelope and dried-fruit packaging formats at the quotation stage, ahead of any production commitment.