“Liquid Crystal” is an attractive material because of both characteristics of fluidity as liquid and anisotropy as crystal. Liquid crystal is widely applied to the display devices, and further, is well known to strongly relate to the living body. Our research covers a wide range of the physical properties in liquid crystal over the academic basis to the practical application such as ferroelectric liquid crystal for the newly developed display device, polymer-complex liquid crystal, blue phase liquid crystal, and biomolecule-doped liquid crystal.
Polymer-Stabilized Ferroelectric Liquid Crystal Display
Ferroelectric liquid crystal displays (FLCDs) are attractive devices because of their unique characteristics such as fast response, bistability and wide viewing angle. However, it is hard to fabricate a defect-free FLC medium. Furthermore, the bistability of FLC is disadvantageous for LCDs which possess grayscale or full-color capability. In order to realize the FLC applications, we have tried to fabricate a defect-free and monostable FLC medium. We succeeded in fabricating a defect-free FLC by utilizing an alignment film having a smooth surface. Moreover, a monostable FLC can be obtained by polymer stabilization technique.
Liquid Crystal for Nano-Structured Materials
Since liquid crystals possess both features of fluidity as liquid and structure as crystal, a nano-scale structure may be easily self-assembled in liquid crystals as well as biological organisms. The liquid crystal blue phase is well known to form a 3-dimensional molecular alignment structure. On the other hand, it is not clear how the blue phase can stably appear in terms of mesogenic and chiral molecules. In this study, we try to formulate an idea of fabricating high functional materials by utilizing liquid crystals through the realization of blue phase appearance, the solidification of blue phase structure, and the investigation of the property such as mechanical strength.
DNA-Doped Liquid Crystal
All matters are formed by atoms and molecules without any distinction of their kinds. However, biological organisms are entirely different from other matters in terms of the self-assembling nano-structure of living tissue and the high responsiveness. On the other hand, distinctive features of liquid crystal system are also the easy self-assembly and the high responsiveness. Therefore, one can easily understand their close connection which inspires us with biological systems being not able to exist without liquid crystal systems. We expect bio-applications such as bio-sensors and medical supplies utilizing liquid crystals and liquid crystal devices with bio-materials which have super-high functionalities. In this research, we focus on deoxyribonucleic acid (DNA) as the biological molecule. It is well known that DNA also can show liquid crystalline states. We study on the DNA-doped liquid crystals and investigate the effect of DNA doping on the molecular alignment structure and the physical properties of liquid crystal for several kinds of DNA molecules formed by adenine, thymine, guanine and/or cytosine bases.