Teijin develops first polycarbonate-resin pillar-less automotive front window; used in EV
19 June 2017
Teijin Limited has developed the first polycarbonate (PC)-resin pillar-less automotive front window for use in the Tommykaira ZZ, a sporty electric vehicle (EV) produced by GLM Co., Ltd., an EV manufacturer launched by Kyoto University.
Automotive front windows must satisfy a variety of regulations, including for light transmission, abrasion resistance and crash safety. While A-pillars provide protection in the event of a frontal collision, thicker A-pillars obstruct the driver’s view. Japan’s new automotive safety standards will require plastics-glazed windows in models released from July to offer enhanced resistance to abrasion and weather.
Teijin’s PC-resin window meets the new Japanese standards; GLM expects to acquire street-ready certification for the Tommykaira ZZ fitted with Teijin’s PC-resin window, and then will offer the window as an option by autumn 2017.
Teijin also will market its PC-resin window for automakers in the US and the EU, where demands for properties equivalent to new standards for safety and security are increasing.
Teijin is leveraging its lightweight, strong, high-performance materials and integrated composite technologies as one of the key focuses of the transformation strategies for the group’s medium-term management plan, under which the company aims to become a multi-material components supplier that works closely with automakers to develop various applications for lightweight automotive bodies.
Teijin, by thickening the perimeter of its PC-resin window, has managed to eliminate the need for the A-pillar, or vertical support that divides the windshield and front window. As a result, the transparent PC resin achieves unobstructed sight lines for safer driving and more enjoyable sightseeing. The integrated PC-resin pillar-less window also is 36% lighter in weight than a conventional front window with an A-pillar.
Teijin already provides PC-resin solutions for plastic glazing, including for train windows, automotive panoramic roofs and quarter windows, leveraging PC resin’s competitive advantages over glass, including 200 times greater resistance to impact and just half the weight.
In March, Teijin developed a new plasma enhanced chemical vapor deposition (plasma CVD) hard-coating technology to the wet hard-coat layer, which offers the same level of abrasion resistance and weather resistance as glass windows. The company collaborated with Tsukishima Kikai Co., Ltd.to develop a plasma CVD pilot plant to treat large PC-resin windows with uniform coatings of plasma CVD. Large surfaces including the size of actual vehicle’s resin windows and those with complex curves are now being glazed at the pilot plant.
|PC resin surface after abrasion test (1,000 rounds). Left: without hard-coat; Middle: wet-method coating; Right: plasma CVD. Source: Teijin. Click to enlarge.|
GLM began mass-producing the Tommykaira ZZ in October 2015. A Tommykaira ZZ model fitted with Teijin’s new PC-resin window will be unveiled at Automotive Engineering Exposition 2017 Nagoya, 28-30 June.