In this study, a one-side zero-azimuth anchoring in-plane switching (OZ-IPS) liquid crystal display (LCD) employing poly(n-hexyl methacrylate) (PHMA) bottlebrush polymers as an application-type zero-azimuth anchoring material was successfully developed. The twist anchoring coefficient A 2 measured for the nematic liquid crystal (NLC) on the PHMA bottlebrush at 25 °C was comparable to that of the same NLC on high-density PHMA brushes. Optimizing the optical design increased the transmission efficiency (TE) of the OZ-IPS cell with the negative NLC to 95%, which was significantly higher than that of conventional IPS cells. Using optical simulation, the OZ-IPS LCDs with a negative NLC clearly exhibited the highest TE (;107% of TN LCDs) for LCDs developed thus far. Moreover, the higher transmittance of the OZ-IPS LCDs was also confirmed for the practical TFT LCD, which exhibited a maximum luminance that was 30% higher than conventional IPS TFT LCDs.

In this article, we describe the conformational characteristics of a cellulosic bottlebrush, i.e., a cellulose derivative of densely substituted side chains, in a dilute solution in order to clarify the effect of cellulosic main-chain stiffness and side-chain crowdedness. Novel cellulosic bottlebrushes 1 with polystyrene (PSt) side chains and methyl groups at the O-6 and O-2,3 positions, respectively, were highly regioselectively synthesized via a protecting group strategy in combination with a copper-catalyzed azide−alkyne coupling click reaction, yielding densely graft polymers where PS chains were introduced in every anhydroglucose repeating unit, i.e., at a "constant" distance of 0.5 nm along the cellulose backbone. Small-angle X-ray scattering measurements of 1 in dimethylformamide revealed that the cross-sectional radius of gyration depended on the degree of polymerization (DP) of the PSt side chains in accordance with the power law with an exponent of 0.50, indicating that the PSt side chains adopted extended conformation because of the inter-side-chain interaction, i.e., the excluded volume effect among the neighboring side chains. Size exclusion chromatography−multiangle light scattering experiments were conducted to determine the main-chain stiffness. Despite the use of a poor solvent for PSt, the stiffness parameter λ −1 was almost independent of the DP of the PSt side chains up to 60, even in the brush regime of side-chains with interchain interaction and hence somewhat stretched conformation. This behavior differs from those of previously reported bottlebrushes of flexible main chains and successfully demonstrated the cellulosic main chain intrinsically so stiff to form bottlebrushes of sufficiently long side chains with little effect on the main-chain conformation. This would expand the diversity in design of bottlebrushes along with the chirality of the cellulosic chain.

In this article, we revealed the mechanism of weak anchoring properties of liquid crystals (LCs) on cross-linked films of bottlebrushes consisting of poly(hexyl methacrylate) (PHMA) and poly(ethyl methacrylate) (PEMA). First, azimuthal anchoring coefficients, A 2 , of a LC were estimated using these two systems from the voltage−transmittance curves at different temperatures. The PHMA and PEMA systems showcased a temperaturedependent weak anchoring property, with A 2 decreasing as the temperature was increased. Second, the degree of swelling of these two systems (with cross-linked films) by the LCs was determined and compared with the phase diagrams of the corresponding mixtures without cross-linking, suggesting that the relaxation dynamics of side chains of bottlebrushes was retained even after the cross-linking. Finally, rheological measurements were conducted for the LC/bottlebrush mixtures to discuss the dynamics of the LCswollen cross-linked bottlebrush films, which clearly demonstrated the relaxation behavior of the side chains. Assuming the time scale for the determination of A 2 , the characteristic temperature corresponding to the side-chain motion was reasonably correlated with the decreasing temperature behavior of A 2 . As a consequence, weak anchoring could be explained by the polymer chain dynamics, which was revealed to be accelerated by the bottlebrush architecture as well as the swelling with LCs, depending on the affinity of the bottlebrush component with the target LC.

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