Innovating sustainably

Sherwin-Williams beverage can pack types

Joseph Campagna, vice president for marketing, packaging coatings at Sherwin-Williams, explains the development of the company’s valPure V70 epoxy coating technology


In practice, being at the forefront of innovative packaging technologies means identifying current and future industry challenges and creating high-performing, safe, and sustainable coatings that set the pace for the packaging coatings market.

In recent years, this has meant staying ahead of emerging regulations. Over the past decade, the packaging coatings industry has been moving away from products containing Bisphenol-A (BPA), PFAS, and other Chemicals of Concern (CoCs), defined here as chemicals that are the focus of heightened regulatory scrutiny or limitations. Coating manufacturers have been challenged to develop new technologies that meet the superior performance standards of traditional BPA-epoxy coatings – while innovating with an ever-shrinking selection of raw materials.

As the regulatory environment becomes more restrictive, simply ensuring compliance with current food contact regulation does not go far enough in creating enduring solutions for the industry. Rigorous R&D methodologies, state-of-the-art chemical screening and toxicological testing are essential to bring solutions to the market that are safe, sustainable and offer superior technical performance.

Sherwin-Williams valPure V70 technology is the packaging industry’s only epoxy coating that does not contain BPA and has been formulated without other common CoCs, like styrene. The development of valPure V70 demonstrates that both regulatory and performance challenges can be overcome through rigorous R&D and a unique approach to product development.

Why epoxy technologies are here to stay

Historically, epoxy technologies containing BPA have  offered  superior  performance,  enabling universal application across different packaging types. They have been ubiquitous across the beverage can market because they are the best performing technologies. However, with the European Food Safety Authority (EFSA) releasing its final opinion to significantly lower the tolerable daily intake (TDI) for BPA, substituting legacy epoxy coatings without compromising safety, performance or high- speed application is a key challenge for the industry. When the industry began exploring different coating technologies to transition away from BPA, most suppliers started with acrylic and polyester solutions. At Sherwin-Williams, we quickly recognised  that  for  many  applications,  these chemistry platforms simply could not match the performance of traditional epoxy coatings with respect to flavour performance, pack performance or ease-of-application.

To solve this problem and create non-BPA coatings that matched epoxy performance, Sherwin-Williams committed to not only formulate, but exhaustively test and identify an epoxy alternative, offering the same superior performance without the use of BPA. Recognising the performance challenges of acrylic beverage coatings early on led us to explore more innovative solutions.

To achieve this, we pioneered our state-of-the-art Safety by Design methodology to ensure that any chemicals screened and identified were safe for intended use, not endocrine active, and would stand the test of time in an ever-changing regulatory environment. Safety by Design is modelled on preclinical pharmaceutical safety evaluations, with a data-led and science driven approach at its core.

Through extensive screening, we identified Tetramethyl Bisphenol F (TMBPF), a chemical that is structurally different to other bisphenols and that is not estrogen active. Once identified, Sherwin-Williams established an entirely new body of evidence to demonstrate the non-estrogenic nature of TMBPF. This consisted of commissioning tests conducted by contract laboratories, validating the data through our Safety by Design process, and engaging third parties for independent estrogen activity testing and evaluation.

For instance, Dr Ana Soto, a pioneering researcher who has conducted over 25 years of research on endocrine-disrupting chemicals, concluded that TMBPF has a toxicological profile that is distinctly and fundamentally different from other bisphenols due its inability to alter estrogenic functional pathways. The unique nature of the chemical structure of TMBPF enables a high performing epoxy coating without the estrogenic activity associated with other bisphenols.

In addition to extensive toxicological testing, we engaged proactively with regulators to conduct additional testing, validating that TMBPF is not a chemical of concern or endocrine-active.

After more than a decade in development, valPure V70 is approved for use in food, beverage, cosmetics and personal care products within Europe, the US, Canada, China and Japan. Compliance in the European Union has been confirmed with the Dutch G4 Commission’s action to update the Dutch Commodities Act, the Warenwet, with the approval of epoxidised TMBPF for use as a food contact material. Furthermore, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) has published two opinions on TMBPF which both confirm that there is no concern about endocrine activity.

As a result of our continued engagement with regulators to demonstrate the safety of valPure V70, TMBPF and TMBPF-DGE were excluded from the restriction of BPA and other Bisphenols of Similar Concern (BoSC) proposed by the German authorities. This reinforces that TMBPF is not viewed as a substance of similar concern to BPA and that there is no intention by the regulator to restrict the use of TMBPF in epoxy resins. TMBPF has been endorsed by NGOs such as the Environmental Defense Fund (EDF) which identified the substance as a known and verified safe alternative to BPA. ValPure V70 is also listed by ChemSec as an evaluated alternative for industry-standard epoxy.

Through a state-of-the-art product development process spanning more than a decade, we have developed the world’s first non-BPA epoxy for the light metal packaging industry. As a result of extensive testing and a science-led approach, TMBPF is now a widely researched and accepted substance for food contact.

Creating a technology like valPure V70 demonstrates that our industry can innovate to develop a lasting, sustainable, and safe solution for the packaging industry.

Sherwin-Williams Safety by Design methodology

Changing consumer demand

So how do innovative technologies play a role in the future of the packaging industry? There is a growing demand for metal packaging, and with that, high performance coating technologies that can support new and challenging brand offerings. Consumers are increasingly making purchasing decisions with sustainable packaging in mind, leading them to reach more often for canned beverages.

As a result, we are seeing disruption in product categories traditionally dominated by plastic or glass, resulting in significant growth in the market for aluminium beverage cans, in the water and wine market, for example. However, both canned wine and canned water are technically challenging to pack and require highly specialised coatings to protect the can and the product inside.

With the emergence of these new products, at Sherwin-Williams we believe the continuation of non-BPA epoxy technologies can offer a high- performance technology that can be universally applied to different can types and support the transition to metal packaging, even in the face of regulatory challenges.

Encouraging innovation

The ability to adapt to a fast-changing regulatory environment is now critical for coatings suppliers. Compliance with existing food contact regulations is no longer enough to ensure lasting solutions that support our customers’ businesses and sustainability objectives.

In the current packaging environment, removing a singular CoC is not enough. New CoCs will be identified in the months and years ahead, and to ensure the health and safety of end users, we must think beyond traditional technologies. If it fails to do so, the industry risks falling into a pattern of regrettable substitution, offering customers inferior technologies that will not meet the increasingly challenging performance requirements of the future. Good isn’t good enough anymore; we must innovate and strive for the best solution possible.

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