Teijin Limited says it has developed the world’s first pillar-less automotive front window molded from polycarbonate (PC)-resin. The front window will be offered as an option in the Tommykaira ZZ, a sporty electric vehicle (EV) produced by GLM Co., Ltd., an EV manufacturer established by Kyoto University.
|PC resin surface after abrasion test (1000 rounds) Left without hard-coat, middle employing wet-method coating, and right utilizing plasma CVD method.|
PC resins are currently prohibited from use in the front windows of automobiles due to existing automotive safety standards. Thanks to its high resistance to abrasion and weather, however, Teijin’s PC-resin window meets new Japanese standards that will become effective in July, paving the way for its use in the Tommykaira ZZ.
By thickening the perimeter of its PC-resin window, Teijin 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.
GLM expects to acquire street-ready certification for the Tommykaira ZZ fitted with Teijin’s PC-resin window, and it then will offer the window as an option by autumn 2017.
Teijin will also market its PC-resin window to automakers in the U.S. and the EU, where demands for properties that satisfy 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 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. 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.
GLM has developed extensive relationships with Japanese enterprises, including Yaskawa Electric Corporation and Omron Corporation, to develop automotive parts based on advanced Japanese automotive technologies. Backed by such support, the company 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, a leading automotive exhibition in Japan, which will be held at the Portmesse Nagoya (Nagoya International Exhibition Hall) from June 28 to 30.
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. Simultaneously, a suitable PC resin will become available for the use in automotive front windows.