New internal coating for metal packaging from Toyo Ink Group
Toyochem Co, the polymers and coatings subsidiary of Japan’s Toyo Ink Group, has launched a new line of Bisphenol A non-intent (BPA-NI) internal coatings for metal beverage bottles and cans.
Based on acrylic emulsion and polyester resins, the new BPA-NI internal sprays and coil coatings for stay-on tab (SOT) ends are specially formulated to achieve the required performance results, while addressing BPA-related health and food safety concerns from regulators and consumers alike. Moreover, Toyochem will be marketing its BPA-NI solutions under the new brand name Lionova, as the company seeks to expand its position in markets overseas.
Traditionally, epoxy resins have been used to line the interiors of metal food and beverage cans. Since epoxy resins are made from Bisphenol A, a potentially endocrine-disrupting substance, epoxy coatings contain small traces of BPA, which is under suspicion of causing health issues. As a result, demand for BPA-NI coatings is gathering momentum as government agencies across the globe start to more strictly regulate BPA and even ban its use in food packaging altogether. This trend has resulted in a shift toward BPA-free packaging in end-use industries.
To meet with this rise in demand, Toyochem researchers in Japan applied its unique polymer design technology to formulate can coatings that do not contain BPA and have very low free monomer content. Designed with human and environmental health in mind, Lionova coating compositions are based on FDA (21 CFR175.300). In evaluation testing, styrene concentrations were below the detection limit of 0.001 µg/L. Lionova systems offer excellent bendability, durability, suitability with a wide range of container types, and retort resistance levels needed to meet the performance requirements of today’s canmakers.
The Lionova Lineup
The acrylic-based LIONOVA-500 for can end coating is a soap-free emulsion suitable for applications that require high hygiene or high-temperature sterilization. They demonstrate exceptional feathering resistance during the shaping process relative to BPA-epoxy coatings, achieving values around 80µm at a dry film weight of 110 mg/dm2.
The high performance polyester-based LIONOVA-600 formulation is composed of optimal functional groups that help to form an optimum cross-linking structure, resulting in exceptional formability and barrier properties based on the polyester’s molecular weight and glass transition point. These coatings are highly flexible and durable with 3T-Bend ERV of 0.1 mA at 110 mg/dm2.
Rounding out the Lionova BPA-NI lineup is the LIONOVA-100 acrylic spray lacquer for DI cans, which demonstrates excellent spray coverage at high speeds and good flavor properties. For bottle can interiors, Toyochem offers the LIONOVA-300 acrylic internal spray features superior bendability and spray coverage reliability for screw processing applications.
“We’re pleased to introduce to the world the new Lionova lineup of BPA-NI internal food-contact coatings for metal packaging,” said Yoshimoto Nakajima, Division Director, Packaging & Industrial Division, Toyochem Co. “The Lionova name derives from the Latin “nova” meaning “new” combined with “lion,” the historical mascot of the Toyo Ink Group. With the rebranded Lionova lineup, we aim to expand our presence in markets in Europe and North America, where BPA non-intent solutions are in high demand, in particular with all major brands. Lionova solutions are able to offer brand owners a novel alternative to epoxy-based liners, while meeting critical mechanical and local regulatory requirements.”