Chirality in a mixture system consisting of bent-core 1,3-phenylene bis[4-(4-8-alkoxyphenyliminomethyl)benzoates] (P8-O-PIMB) and rod-like n-pentyl-cyanobiphenyl (5CB) molecules has been studied. Precise circular dichroism (CD) spectra using thin sample cells indicate mainly two characteristics: (1) the origin of CD signals is due to chiral-segregated bent-core molecules in the B(4) phase, where 5CB is in the isotropic phase; (2) the enhanced CD signal is detected in the B(X) phase, where 5CB is in the nematic phase. These results suggest that 5CB molecules are embedded in the network of helical nanofilaments formed by P8-O-PIMB and form helical superstructure with the same handedness as the helical nanofilaments in the B(X) phase, resulting in the giant CD signals.

We successfully developed a new achromatic quarter wave film for anti-reflection of OLEDs, consisting of multiple layers of liquid crystal materials. Applying an original optical design, a new liquid crystal compound, and multi-layer coating technology, we realized OLEDs with very low reflection in all viewing angles. This new film can be produced in a rolled single-sheet state, which enables the manufacture of a circular polarizer with high productivity by a conventional roll-to-roll process. Author Keywordsliquid crystals; quarter wave film; wide viewing angle; OLED; optical compensation film; discotic material. Objectives and BackgroundThe rapid spread of mobile devices, led by smartphones and tablet PCs, is progressing. OLEDs are growing in popularity as the display technology for these applications. OLEDs are well suited for mobile devices due to the high color saturation in their light emission, large field of view, and thin profile. However, a circular polarizing film is indispensable for OLEDs to obtain good black mode performance.Conventionally, achromatic quarter wave films (QWFs) have been used for the circular polarizing film. A superposition of a /4 and a /2 film or a polycarbonate-derivative QWF has been used because of their achromatic optical performance. However, these films' drawbacks include a narrow anti-reflection viewing angle and a complicated production process.To solve these problems, we developed a new achromatic QWF consisting of multiple layers of liquid crystal (LC) materials. We extended the alignment technologies of discotic and calamitic (rod-shaped) LC materials which we have been developing for many years [1,2], and succeeded in controlling the multi-layer alignment. Further, we applied a new optical design that allows adjustment of the total out-of-plane retardation of the multiple layers so that a wide anti-reflection viewing angle is obtained. This achromatic QWF can be produced by a roll-to-roll process because the alignment direction of each of the two LC layers is independently controllable. Results and DiscussionOptical Design: A circular polarizer in combination with a reflector prevents reflection by suppressing the exit of incident light. The black mode of OLEDs, which is derived from the light shielding characteristics of the circular polarizer, has a great influence on display performance properties such as contrast and color. The QWF is characterized by the wavelength dispersion of its birefringence. It is not easy to provide the same characteristics over the entire range of visible light.There are two ways to control the wavelength dispersion. One is to use reverse wavelength dispersion materials [3], and the other is to stack retardation films with an axial design (a superposition of a /4 and a /2 film) [4]. It is reported that some materials exhibit this reverse wavelength dispersion. However, the dispersion obtained by a single sheet of retardation film is not enough to achieve achromaticity. Therefore, we attempted the second approach, stacking retardati...

A set of precise measurements of UV-Vis absorption spectrum for the classical bent-shaped molecule, P-12-OPIMB, revealed that molecular exciton interactions exist even in the mesophases of this system, as manifested as an obvious and abrupt change in the positional and spectral shape at phase-transition points. Based on Kasha's molecular exciton model, we successfully conducted a quantitative analysis of the spectral shift and could determine the local structure of the B4 phase. To the best of our knowledge, such a spectroscopic analysis for the liquid crystals has not been connected with the local structure.

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A simple rate-based method for recovering sucrose from sugarcane molasses is proposed, focusing on the feasibility of continuous processing. When ethanol is gently poured onto diluted molasses, sucrose is transferred to ethanol along with water, resulting in the formation of a distinct third layer composing sucrose positioned between the ethanol and diluted molasses. Although the third liquid layer is metastable and dissipates when vigorously stirred, its sucrose concentration reaches a level suitable for sucrose crystal formation. Consequently, by continuously withdrawing the third layer while supplying ethanol to the diluted molasses, a semi-continuous operation for sucrose recovery from diluted molasses is achieved. To predict the concentration changes of sucrose over time within the third liquid layer, simple mass-transfer models based on diffusion and axial dispersion are employed. While the prediction yields limited success, it underscores the significance of mass-transfer from the liquid jet in the third layer and the role of mild mixing within the layer in facilitating its growth and interior mass-transfer. This study presents the first description of the effective utilization of the third liquid layer in solvent extraction and a method to control its formation and mass-transfer for sugar recovery from molasses.