Sun Chemical announced that it has obtained RecyClass certification for its SunUno SoliCycle range of solvent-based inks intended for printing flexible packaging. The product is an alternative to nitrocellulose-based ink systems and was developed for flexographic and gravure applications. According to the company, when combined with certified laminating adhesives from the SunLam range, it forms a complete system compatible with recycling processes. The manufacturer states that it is the first supplier to offer both nitrocellulose-free inks and certified laminating adhesives, and also one of the first manufacturers whose solvent-based inks, positioned as an alternative to nitrocellulose-based systems, have received RecyClass certification. The certification is intended to confirm the solution's compliance with requirements for technologies used in the production of packaging with higher recyclability and to support converters and their customers in documenting such compliance.
According to Sun Chemical, the growing importance of designing packaging for recyclability and circularity is currently one of the key development directions of the European packaging market. Expectations placed on suppliers are shaped both by industry initiatives such as Ceflex and by the regulatory environment, including the Packaging and Packaging Waste Regulation, PPWR. In this context, RecyClass plays an important role as a European cross-industry non-profit initiative that develops science-based design-for-recycling guidelines, recovery assessment protocols and certification schemes supporting the circularity of plastic packaging.
Nitrocellulose-free inks for flexible packaging
Sun Chemical indicates that nitrocellulose-based inks are currently undergoing closer scrutiny because the presence of NC may negatively affect the recyclability of plastics and reduce the value of recyclate obtained in the recycling process. The company's response to these challenges is the polyurethane-based SunUno SoliCycle range. The solution was designed for printing flexible packaging and, according to the manufacturer, meets current legal requirements while maintaining the performance parameters necessary for the production of high-quality packaging.
According to the manufacturer, SunUno SoliCycle is a versatile solution and can be used both for printing the final surface and for films intended for subsequent lamination. The system is offered as ready-to-use inks and also in a modular form including concentrates and technical varnishes. This product structure is intended to allow printers to adapt formulations to the requirements of a specific production job.
The role of polyurethane and raw material supply
The company recommends polyurethane as a raw material replacing nitrocellulose in ink systems, pointing to its stability, high performance and compatibility with recycling processes. Sun Chemical uses a polyurethane supply chain operating within the group. It includes parent company DIC, which the company ranks among the world's ten largest producers of polyurethane resins, as well as Sapici, acquired in 2022. According to the manufacturer, this is intended to ensure high raw material availability.
Sun Chemical states that this allows it to combine its in-group polyurethane resins with its own pigments. In the company's assessment, this translates into a stable ink system with consistent viscosity and greater compatibility with recycling processes than traditional nitrocellulose-based inks.
A complete system with SunLam adhesives
The offer is complemented by laminating adhesives from the SunLam range, which also hold RecyClass certification. According to the manufacturer, they have been adapted to industrial recycling lines for flexible polyethylene packaging and are fully compatible with the recycling of coloured PE. The ULM adhesive range includes solutions providing medium or high performance, depending on the packaging structure used.
The company emphasizes that combining nitrocellulose-free inks with certified SunLam adhesives makes it possible to offer a complete system from a single supplier for the production of recyclable flexible packaging.
Romain Cleret, Product Director, Flexible Packaging, Sun Chemical EMEA, said: "We are proud to be among the first companies in Europe to obtain RecyClass certification for versatile solvent-based inks that are an alternative to nitrocellulose-based systems, and to be able to offer a range of certified solutions for the production of flexible packaging. This system allows our customers to adapt production with greater confidence to changes taking place in the industry and its transition towards packaging with higher recyclability. As the market continues to develop, we will consistently develop further solutions that respond to our customers' needs"
