Synthesis of highly birefringence liquid crysalline polymers for optical materials

2018 Fiscal Year Final Research Report

• Project/Area Number: 26288058
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Polymer chemistry
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Gen-ichi Konishi 東京工業大学, 物質理工学院, 准教授 (20324246)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 高複屈折性液晶 / 液晶 / パイ電子系

Outline of Final Research Achievements

We designed new bistolane nematic liquidc crystals with alkylsulfanyl groups for extraordinary birefringence materials. A symmetric derivative contains short terminal methylsulfanyl groups (SCH3) on both ends, while two asymmetric derivatives contain a methylsulfanyl group on one end, as well as a highly polarizable cyano (CN) or isothiocyanate (NCS) group on the other end. These materials exhibited a well-defined enantiotropic nematic phase, as well as an extremely high birefringence (Δn > 0.6). Most notably, the NCS derivative achieves an extremely high value of 0.77 at 550 nm.

Free Research Field

有機材料化学

Academic Significance and Societal Importance of the Research Achievements

高複屈折性液晶材料はLCDフィルム、レーザー発振用フィルム、光記憶デバイス等への応用されており、さらなる高複屈折化が求められている。高複屈折性液晶は、偏光板やLCDフィルムを単一成分で作製することができ、ディスプレイの性能向上、大画面化、製造コストの削減など、そのインパクトは計り知れない。今回、実用化にはいくつかの壁があるが、上記の条件を満たす、複屈折0.8に迫る液晶材料の開発に成功した。