Royal DSM, a global science-based company active in health, nutrition and materials, says producers of wearable electronics are turning to its Arnitel® thermoplastic elastomer for soft straps. A new high performance solution that it created specifically for the application has been adopted by several companies, including Samsung for its latest Galaxy Gear S2 smartwatch.
The wearables industry is currently booming. By 2020, annual sales are expected grow to 200 million devices, with smart watches and activity trackers taking the largest share of the market. Alongside functionality and the accessibility of the interface, wearability is obviously a key consumer requirement, as well as overall esthetics. Comfort, color, and how the device feels on the skin all play a very important role in product design. This argument applies just as much to the strap as to the device itself.
Samsung chose DSM’s Arnitel compound for the Galaxy Gear S2 strap for its good balance of physical and chemical properties: the strap has superior soft touch and feel, is very comfortable to wear in direct skin contact and is certified to USP and ISO standards covering biocompatibility of devices. Arnitel is resistant to perspiration and to the various oils and other liquids that the strap of the watch is likely to come into contact with during use.
Furthermore, the material is easy to process via injection molding, and can be used in overmolded structures with other thermoplastics such as polycarbonate, ABS and thermoplastic polyesters. The intrinsically bright Arnitel polymer, together with its high UV resistance, enables the production of compounds in a broad range of colors, including ultra-white.
During the development of the Galaxy Gear S2 strap, Samsung was provided with strong and rapid-response support in up-scaling from prototypes to high-volume molding from DSM’s local team in Korea, backed up by its research and product development operations in Europe and China.
Arnitel scores over rival materials such as thermoplastic polyurethanes and thermoset silicone elastomers also in terms of sustainability. Arnitel is free of any halogen, red phosphorous or fluoropolymers and is fully recyclable. “This is in particularly important for OEMs and manufacturer targeting consumers with a strong awareness of their environmental footprint,” says Fredric Petit, Global Business Director Arnitel.
As an indication of the strong importance of aesthetics in wearables, DSM has for the first time ever introduced fragrances into the world high performance plastics for such applications. Arnitel is available in different scents, such as lemon and rose, enabling OEMs to provide their customers with an additional sensorial experience. “Arnitel is much more than a standard high performance material providing a technical solution,” says Eric Choi, Account Manager with DSM in Korea. “At the important interface in direct contact with consumers it provides a complete package of high performance, good design, excellent touch and feel, and now a great smell too!”
Biocompatibility certified according to USP and ISO standards
DSM has put considerable effort into ensuring that wearable products made in Arnitel do not cause skin irritation or allergies. Tests carried out on several grades of Arnitel intended for wearables show that they comply with two important international standards, set by the United States Pharmacopoeia (USP) and the International Standards Organisation (ISO), relating to biocompatibility of medical devices. They comply with ISO 10993, and they achieve the highest classification, Class VI, according to the USP standard.
