As Amcor's awareness and understanding of "substances of concern" grow, we continue to modify the materials utilized in food packaging to ensure the safety of the packaged product while minimizing the system's overall environmental impact. Some current food packages use coatings that contain poly(vinyl chloride) as sealants, i.e., package closure surfaces, in especially demanding situations like immersion in boiling water. Although food contact packaging materials like polymers produced from vinyl chloride and styrene continue to be positively sanctioned by global agencies like the US FDA and EU's EFSA, increased health and/or environmental concerns have led Amcor to seek alternatives, especially regarding their use as heat seal coating components used to close packages. Amcor has examined a variety of alternative coating chemistries, including polyesters and polyacrylates, but has not yet satisfactorily met the fitness-for-use requirements, especially those related to adhesion, for all applications.
Amcor is looking for a food law compliant (direct contact) heat seal coating that may be applied onto one surface of aluminum foil 
The coating's primary performance criteria require maintenance of adhesion to aluminum and seal integrity while immersed in boiling water. An ideal coating will be solvent borne with a viscosity suitable for application via a continuous roll-to-roll process like coil coating.
- Solutions must not contain vinyl chloride, styrene or polymers containing vinyl chloride or styrene.
- Coating-to-aluminum (e.g., alloys AA1200, AA8011A, AA3104) adhesive strength ≥ 12 N/15 mm sample width following immersion in 100 °C water for 5 min (modified ASTM F904)
- Coating-to-coating seal strength ≥ 12 N/15 mm sample width at 180 °C; 1 s seal dwell time; 600 N seal force following immersion in 100 °C water for 5 min (modified ASTM F2029)
- Compliance with global food contact regulations - Amcor can assist applicants with understanding specific compliance requirements
- Coating must not block, i.e., when applied to a substrate and wound into a reel, it must unwind without sticking to the opposite surface.
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Solvent borne solutions (e.g., MEK, acetone, ethyl acetate) are strongly preferred, but waterborne and 100% solids options (including radiation curable solutions) will be considered.
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Solutions that do not interfere with silicone curing are strongly preferred. Known curing inhibitors include amines, amides, urethanes, organic acids, sulfur compounds and organotin compounds.
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Solutions that utilize one or two coating layers (e.g., heat seal coating only or primer + heat seal coating) are preferred.
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Solutions with solids contents ≥ 20 wt-% are preferred.
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Solutions that show no evidence of coating-to-aluminum delamination following elongation of 15% are preferred.
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Solutions known to be toxic in usage or in handling
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Solutions that contain materials whose usages are restricted (or are likely to be restricted) by legislation, e.g., BPA, PFAS, ortho-phthalates, heavy metals, and epoxy silanes
We solve packaging challenges, around the world every day. We develop differentiated products, services and processes to protect your products and the people who rely on them, all around the globe. Drawing on unrivaled heritage in design, science and manufacturing, more than 1000 R&D experts are innovating new materials, formats and technologies to better protect your products.
In 2018 we pledged to develop all our packaging to be recyclable or reusable by 2025. On our journey to our 2025 pledge we are innovating across various sustainability options, delivering you more sustainable packaging solutions under the new EcoGuard™ brand.
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