Reducing the weight of mobile device housings demands a combination of thin-wall molding and high rigidity, and materials that currently meet these requirements include carbon fiber-reinforced plastics and magnesium alloys. However, these materials require additional steps for pattern printing, coating or other post-processing after the housing has been molded. These added production costs have limited use to some high-end models, Teijin said.
Conventional PC or nylon resin composites are commonly used for the housings of mass-market models, but these materials are prone to wrinkles, cracks or other degradation in surfaces during in-mold decoration. Also, it has been a challenge to achieve desired levels of dimensional stability, coating and flame retardancy in this-wall molded components made of these materials.
By incorporating special glass fibers and additive agents, the new PC resin achieves excellent rigidity and dimensional stability for thin-wall molded casings, as well as optimized surface flatness for in-mold decoration and 40% higher fluidity than conventional glass fiber-reinforced PC resins, said Tejin's information. Additionally, Teijin's proprietary flame-retardant technology enables the new PC resin to achieve increased flame retardancy, equivalent to UL94V-0 at 0.6mm.
Teijin's primary businesses include high-performance fibers such as aramid, carbon fibers and composites, films, resin and plastic processing, and polyester fibers. The group has 150 companies and approximately 17,000 employees across 20 countries worldwide.