Since fiscal 2003, Sharp has been working in collaboration with NEC Tokin Corporation, Union Seimitsu Co., Ltd. and Tokai University in Japan to develop mass production technology for parts that are easy to disassemble for recycling. The resulting fastener consists of a screw and a washer that is made of TiNi^*1 shape-memory alloy^*2. The washer remains securely fastened in use (Fig. 1) but expands when heated (Fig. 2), enabling the two combined pieces to come apart easily (Fig. 3).
In fiscal 2005, Sharp applied this easy-release fastener to chargers of cordless handsets for phones (CJ-N77CL/N773W). Sharp plans to develop its applications to include home appliances in the future.

*1 TiNi: Alloy made of titanium and nickel

*2 Shape-memory alloy: An alloy that deforms at a certain temperature, but recovers its original shape when heated.