Innovating metal packaging inks sustainably

By Eduardo Alegria, director and global champion, metal deco inks at Sun Chemical

The metal packaging industry is evolving rapidly, in line with increasing sustainability and compliance demands. In this evolving landscape, ink technology plays a pivotal role, not just as a component of the final product, but as a strategic enabler of change across the whole value chain.

At Sun Chemical, we believe that future- ready ink solutions must go beyond performance. They must lead the way towards compliance, circularity and production agility, responding to the needs of printers, can makers, brand owners and ultimately consumers. Our mission is to help the industry transition confidently into this new era by redefining what inks for metal packaging can do.

The requirements of inks for metal packaging are designed and developed with four perspectives in mind. From a printer’s perspective, the ink must run smoothly and efficiently on press, improving uptime and reducing waste. For can makers, inks must survive the mechanical stresses of the can making and filling processes without compromising performance.

Brand owners require vibrant, consistent colours that accurately and distinctively reflect their brand. Consumers need assurance that the packaging materials are safe and compliant with food contact and regulatory standards.

This requires ink formulators to balance performance and visual appeal, while adapting to evolving industry standards and equipment technologies, without compromising compliance and safety.

Sun Chemical offers a comprehensive range of inks tailored to the specific requirements of different metal packaging formats.

For two-piece cans, the SunDuo range offers superior press performance, consistent quality and high-speed printability. The technology used minimises production waste, with high ink stability enabling quicker start-ups and reducing can rejections after line stoppages. We believe guaranteed colour accuracy on new label start-ups ensures outstanding quality from the very first run.

For three-piece can and closure applications, Sun Chemical’s SunTrio range delivers versatility. It includes both the Daimetal series, which offers a solid, conventional performance, and the Toba series, which provides enhanced flexibility and chemical resistance – which is unique in the market. SunTrio also includes a range of UV-curable inks, including the a low-migration UV ink unique to the metal packaging sector, as well as LED-curing options.

For aerosol cans and aluminium bottles, SunAltec inks are specially formulated to meet the high standards of the cosmetics and pharmaceutical industries. These products offer visual appeal and precision. A particularly innovative development is the ability to produce both matte and gloss finishes in the same monobloc aerosol container, helping brand owners differentiate their products on the shelf. The brilliance of Sun Chemical’s colours allows its customers to have an excellent colour gamut, and precisely manufactured inks that ensure quality and reliability.

To support colour accuracy across applications, several advanced tools were developed as part of the SunColorBox suite. Pantone colours can be digitally represented as they appear on aluminium, ensuring accuracy across the entire value chain and decreasing time to market.

One key tool from the SunColorBox suite is SunDigiProof, which provides customers with colour proofs that accurately depict how the final colour will appear on metal substrates. This allows for quick approvals without full production runs. SunDigiGuide complements this by offering a digitally printed book that is designed to help converters show their customers the full choice of the spot colours they already have at their disposal.

Together, these tools streamline the colour approval process and workflow from weeks to hours, all while ensuring visual consistency.

Sun Chemical remains committed to sustainability – and we take a top-to-bottom approach that can be seen in our annual sustainability report, where we work across the ‘5Rs’ that ensure our people, products, processes and partners are aligned with sustainability objectives: Reuse – reduce single-use packaging; Reduce – packaging doing more, with less; Renew – benefit with bio-renewable materials; Recycle – feed the circular economy; and Redesign – re-evaluate for greater efficiency.

In the metal packaging sector, this includes both product-level innovation and operational practices. For example, recycled PET is incorporated into some inks, achieving up to eight per cent recycled content without compromising performance. Sun Chemical is also reducing energy use by shortening production cycle times and helping customers transition from traditional curing systems to UV and LED technologies, which consume significantly less energy.

Sustainability roadmaps have been established at our key factories, which include targets based around waste reduction, energy efficiency and employee awareness, reinforcing that sustainability is not just an R&D concern but also an operational priority.

Regulations surrounding hazardous materials are becoming increasingly stringent, compelling manufacturers to innovate alternatives for metal decorating. One notable example is the red pigment RD.53:1, also known as red lake C, which is expected to be reclassified as carcinogenic, mutagenic and reprotoxic. In response to this development, Sun Chemical has introduced a barium-free alternative. This proactive action reflects the company’s ‘Beyond Compliance’ philosophy to regulatory and environmental responsibility.

Additionally, scrutiny over melamine formaldehyde resins, widely used in inks for beverage packaging, has driven Sun Chemical to develop melamine- and formaldehyde-free alternatives, which was possible due to the vertical integration of Sun Chemical’s supply chain.

Our strategy is guided by four main pillars: brand evolution, efficiency, risk mitigation and sustainability. These drivers influence every action taken, whether in commercial decisions, product development or operational investments.

Looking ahead, the most anticipated significant shift is the rise of digital printing in metal packaging. It’s difficult to predict how long this will take, but it will happen. Sun Chemical digital inks are already operating in all the markets, but scaling these technologies to true mass production requires close collaboration among the SunJet division, suppliers and customers to meet the specific demands of metal packaging and ensure the company has a leadership position.

Sun Chemical’s innovation commitment will help ensure customers can meet their present and future challenges in metal packaging.