Design for Recycling

Executive summary

The EU Packaging and Packaging Waste Regulation (PPWR) makes recyclability a legal design requirement: all packaging placed on the EU market must be recyclable by 2030 and recycled at scale by 2035, with graded performance classes and rising recycled-content obligations. Inks and coatings are a small fraction of a pack’s mass and a large fraction of its recyclability problems. This paper sets out how inks affect paper and plastic recycling streams, the tests that quantify it, and the formulation choices — de-inkable water-based and UV systems, mono-material-compatible inks, repulpable barrier coatings — through which Uniform Industries designs for recycling.

Figure 1 – Regulatory timeline: PPWR recyclability dates alongside the EuPIA Charter, EUDR and TPO exclusion.

1. Paper: de-inkability

Recycled fibre is only useful if it is bright, and brightness depends on removing ink in flotation de-inking. In the pulper, alkaline conditions at 40 – 50 °C release ink from fibre; in flotation, surfactant-coated air bubbles carry hydrophobic ink particles of 10 – 100 µm to the froth. Inks fail de-inking in two ways: they fragment into particles too small to float (below ~ 5 µm), which grey the pulp, or they remain as large, flexible flakes that pass screens and appear as dirt specks. The INGEDE Method 11 test and the EPRC De-inkability Scorecard measure luminosity, colour shade, dirt specks, filtrate darkening and ink elimination, and assign a score.

Ink chemistry determines the outcome. Oxidatively drying offset inks with mineral-oil vehicles de-ink well. Water-based acrylic inks de-ink well when the binder redissolves in the pulper and releases pigment at a floatable size — which is the case for the UniLux and UniCraft ranges on standard papers. UV-cured inks and coatings are the difficult case: a cross-linked film does not redissolve; it must break into flakes of the right size and float. Formulation for de-inkability in UV means controlling cross-link density and film flexibility so that the film fragments into floatable particles rather than staying as sheets or grinding into fines; UniCure grades developed for paper packaging are tested to this protocol.

Figure 2 – De-inkability scores by ink technology on the EPRC scorecard (illustrative).

2. Barrier and functional coatings: repulpability

A coating that prevents the pack from breaking down in the pulper, or that forms tacky residues (“stickies”) on paper-machine surfaces, excludes it from the paper stream regardless of ink. Dispersion barrier coatings are tested by pulping under mill conditions and measuring fibre yield, residual coating particle size and stickies potential, using the Cepi recyclability test method or equivalent. Repulpable barrier coatings at typical coat weights pass; extruded PE and most wax-laminated structures do not. Uniform Industries’ barrier-coating development is qualified against these protocols from the outset.

3. Plastics: mono-material and the mechanical recycling stream

Flexible packaging is moving from multi-material laminates (PET / aluminium / PE) to mono-material polyolefin structures that can be mechanically recycled. Inks affect this in three ways. Compatibility: ink that stays in the recyclate colours and can contaminate it; the industry’s approach (RecyClass, CEFLEX design guidelines) prefers low ink coverage and inks that either wash off in the hot caustic wash of the recycling line or are compatible with polyolefin melts. NIAS: ink components can become non-intentionally added substances in the recyclate; low-migration chemistry helps here too. Detection: carbon-black inks and dark full-coverage prints defeat near-infra-red sorting; NIR-detectable blacks and reduced coverage keep the pack sortable. Uniform Industries’ surface-print and lamination inks for polyolefin films are formulated with these guidelines in mind, and washable-ink grades for de-inkable plastic recycling are under development.

4. What design for recycling means in practice

Choose the stream first. Decide whether the pack is paper, mono-PE, mono-PP or PET, and select ink and coating systems tested for that stream.

Minimise coverage and film weight. Less ink is less to remove; strong pigments and fine aniloxes serve both quality and recyclability.

Avoid cross-stream contaminants. No metallised layers or foil on paper packs intended for repulping; no PVC or PVDC on plastic packs; no carbon-black on NIR-sorted plastics.

Test the finished pack. De-inkability, repulpability and recyclability are properties of the whole structure; test it as it will be sold.

Document. PPWR’s performance classes and the growing number of national EPR fee modulations reward documented recyclability.

5. The wider frame

PPWR sits alongside the EU Deforestation Regulation (fibre sourcing; application expected from late 2026 for larger companies), the EuPIA Charter for ink raw materials, and the food-contact framework. Together they define an ink that is safe to make, safe to print, safe to eat from and safe to recycle. Uniform Industries formulates to all four for every market it serves.

Key takeaways

Recyclability is now a legal design requirement with dates.

De-inkability and repulpability are measurable; water-based and correctly formulated UV systems pass.

On plastics, low coverage, washable or compatible inks and NIR-detectable blacks keep packs in the mono-material stream.

Test the finished structure, and document it.

References: Regulation (EU) 2025/40 (PPWR); INGEDE Method 11; EPRC De-inkability Scorecard; Cepi recyclability test method; CEFLEX Designing for a Circular Economy guidelines; RecyClass design-for-recycling guidelines.