Ink safety is the most overlooked part of hang tag packaging: buyers audit the paper and the finishing, but rarely ask about the ink system. Pigment-bound heavy metals, azo colorants, plasticisers and residual solvents can nonetheless migrate onto garments by contact, stacking or odour — and become the weakest link in a compliance audit.
This guide covers six parts — ink types, migration routes, regulations and testing, low-migration options, odour and lamination details, and the information to send before sampling — so ink safety becomes a few tickable lines on your inquiry sheet.
1. Choosing Among Four Common Ink Systems
| Ink system | Main traits | Best fit | Watch out for |
|---|---|---|---|
| Vegetable-based offset ink | Low odour, renewable content, stable colour | Volume offset runs on standard paper tags | Slower drying, slightly lower saturation than solvent ink |
| UV ink | Instant cure, abrasion resistant, supports gloss and thick film | Dark solid areas and tags needing rub resistance | Under-cured film can leave photoinitiators and persistent odour |
| Water-based ink | Low VOC and odour, closer to eco-packaging requirements | Paper bags, eco tag ranges and inserts | Weaker water resistance — confirm the surface treatment |
| Solvent-based ink | Strong adhesion, vivid colour, works on non-absorbent substrates | Synthetic paper, PVC tags, coated substrates | Residual solvent odour and restricted substances — request test reports |
2. How Migration Happens: Four Routes
- Direct contact: tags resting against garments for weeks, especially in a warm warehouse, transfer ink components onto the fabric
- Set-off in stacks: bundled before full drying, the front ink transfers to the back of the next tag and later to garments
- Odour uptake: solvent vapour trapped in sealed poly bags is absorbed by the fabric, worst with dark solvent ink plus lamination
- Mouthing: children's wear tags may be mouthed, which shifts the focus from skin contact to migrated element limits
Of the four, set-off and sealed-odour are the two a factory can control most easily and the two that generate the most complaints; contact and mouthing need material choice and testing as backstops.
3. Regulations and Tests Worth Knowing
- EU REACH Annex XVII: restricts azo colorants releasing certain aromatic amines in textile and leather articles and sets limits on cadmium and lead; tags ship as accessories and buyers usually require them to comply as well
- EN 71-3: the migration of certain elements test from toy safety, frequently applied by children's wear brands to trims and packaging — it measures heavy metals released under simulated mouthing
- US CPSIA and California Prop 65: the first governs lead and phthalates in children's products, the second drives exposure warnings — dark inks and plastic parts are frequent triggers
- Buyer RSL: a brand's restricted substances list is often stricter than the law — ask for it at inquiry stage, which costs far less than reworking later
- System certifications: printing chemicals can follow a route such as OEKO-TEX ECO PASSPORT, while paper trims add FSC and recycled-content claims that pair with the ink declaration
4. Building a Low-Migration Setup
- Start with ink systems using heavy-metal-free pigments, and ask for the pigment list plus test reports rather than a bare claim of eco ink
- Reduce large dark solids: shift to light backgrounds, white space or spot colour and both migration and odour drop
- Avoid systems containing phthalate plasticisers, above all PVC tags and plastic parts — this is the group buyers screen hardest
- Weigh the finishing: lamination or varnish forms a barrier layer, yet the adhesive itself needs an odour and migration check
- Test at sample stage rather than after bulk production, then freeze the passing specification so every later run uses the same formulation
5. Odour and Lamination: Three Details Easily Missed
- Solvent odour is amplified inside sealed poly bags — leaving time to air out before shipping beats fixing it later
- Under-cured UV ink brings odour and set-off together; controlling curing energy works better than laying down more ink
- With recycled paper plus dark ink the perceived odour is stronger; if unboxing smell matters to the channel, move dark ink onto coated stock
6. Six Things to Tell Your Supplier Before Sampling
- Target market and sales channel, and whether the item is children's wear — this decides which limits apply
- Which standard governs testing — EN 71-3, CPSIA or your own RSL — and who submits the samples to the lab
- Any preference or restriction on paper and ink system, for example whether solvent ink is acceptable
- Printed area and colour distribution — whether large solids and dark tones are involved
- Finishing list: lamination, varnish, foiling, spot UV, and whether each one touches the garment
- Packing method and documents: whether bags are sealed, and which test reports or declarations you need
Related Articles
- Trims FAQ: all articles
- Hang Tag Printing Methods Explained
- Trims and California Prop 65
- Trims Certifications: OEKO-TEX, GRS and FSC
Need a hang tag that clears a compliance audit? Send your market, channel and test standard — we quote and sample on a low-migration ink system, arrange lab testing at sample stage and attach written ink and paper declarations.
Request an ink safety plan →