Bendy resin makes a spectacle of itself

Flexible frames are up to 50% lighter than metal

Tokyo-based eyewear retailer Intermestic has chosen Ultem polyetherimide (PEI) resin from Sabic Innovative Plastics for the frames of its new line of Zoff Smart spectacles.

Intermestic’s use of aerospace-grade Ultem is intended to meet Japanese consumer demand for new eyewear styles with “exceptional” long-term performance and light weight, allowing the company to eliminate titanium and aluminum from the material selection process.

According to Sabic, Ultem provides excellent flexibility, flame retardance and resistance to chemicals, heat and ultraviolet (UV) light, as well as greatly expanding design freedom by virtue of its mechanical properties.

Takeshi Ueno, president of Zoff, says “We are delighted with the capabilities of Sabic’s Ultem resin, the exceptional elasticity of which allows you to bend the spectacle earpieces freely. The high quality and performance of this Sabic technology continue to help us achieve a competitive advantage in our market segment”.

According to Sabic, the Japanese eyewear sector is expected to grow from 450 billion Japanese yen (JPY) (£3.5 billion) in 2011 to 1 trillion JPY (£7.8 billion) in 2015.

Sabic clams that Ultem offers excellent elasticity coupled with resistance to deformation, allowing the spectacle frame to be bent easily, yet returned to its original shape. Zoff Smart frames made with Ultem resin meet the relevant Japan Standard Association JIS B 7285 standard, the testing for which includes 20,000 bending repetitions (opening and closing the frame). The resin’s dimensional stability ensures that the lenses are retained in the frame, while heat deflection resistance at high temperatures protects the frame even when left on a car dashboard in hot sun.

In addition to its low density (up to 50% lighter than metal), Ultem resin is suitable for precision thin-wall moulding, according to Sabic. The Zoff Smart weighs 9.4 g without the lens, as compared with equivalent metal frames typically weighing around 20 g. Ultem can be custom coloured to provide a wide range of aesthetic effects.

Other potential eyewear applications for Ultem resin include entertainment eyewear (such as 3D glasses) and safety glasses.

[ Back ]