Materials developer Teijin Limited has engineered a formable gasoline-resistant film made of PLANEXT® SN4600, an improved grade of the company’s PLANEXT® bioplastic. The material, formulated to replace chrome plating, is being used by Honda Lock Mfg. Co., Ltd. for nonconductive door handles integrated with smart-entry systems.
The film was developed using a special metal-evaporation technology from a processing-manufacturer partner. Teijin is currently developing other automotive applications in addition to mass producing the film for door handles.
PLANEXT is an eco-friendly bio-polycarbonate made with bio-content based on isosorbide from corn-starch and other plants. In addition to excellent moldability and durability, it is superior to oil-derived polycarbonates in terms of surface hardness, weather and chemical resistance, and light transmittance. In addition, polymer reforming is used to give PLANEXT SN4600 important new properties, including gasoline resistance, formability and UV resistance.
The gasoline-resistant film is ideal for vehicle doors; optimized heat resistance and filming technology enable high formability for fashioning into complicated shapes. UV protection helps to shield the base material and prevent discoloration.
Vehicle door handles are increasingly being integrated with secure smart-entry systems that allow doors to be locked and unlocked by simply placing one’s hand on a handle sensor. The material surrounding the sensor, however, must be nonconductive to avoid sensor malfunctions, so conventional door handles made of electro-conductive chrome plating coated on a resin base are not suitable.
Plastic films made with a metal-evaporation process are nonconductive and already being used as metal substitutes for automotive exteriors, but they are not suitable for door handles because they are neither gasoline-resistant nor highly formable.