We investigated the effect of a chiral additive on the splay to bend transition rates for an optically compensated bend (OCB) mode. The splay to bend transition consists of the symmetric-splay to bend transition and the asymmetric-splay to bend transition. The symmetric-splay to bend growth rate is independent of concentration of the chiral additive. On the other hand, the chiral additive has pronounced effects on the acceleration of the asymmetric-splay to bend growth rate. This acceleration is attributed to a chirality-induced hybridization of top-splay alignment and bottom-splay alignment.

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A new single-cell-gap transflective LCD using the OCB-mode LCD compensated with hybrid-aligned discotic liquid crystal films and C-plates was designed to improve the response time and viewing-angle performance of transflective displays. We verified that a wide viewing-angle exceeding 80 [degree ] (CR over 10:1) and high contrast ratio over 1000:1 could be achieved in both reflective and transmissive parts by using optimum design parameters of compensation film.

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We have been investigated photo degradation of liquid crystal(LC) cell under the blue-violet laser diode(403nm). In this study, the laser diode is focused with an object lens, and exposed to LC cells with homogeneous, twisted nematic orientation. The degradation in the TN cell, started earlier than that in the homogeneous cell. We also exposed LC cell under the voltage application. Photostability hardly changed in LC cell with both orientation. Therefore, we thought that photo degradation happened in interface between LC and alignment film.

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Thick Liquid crystal (LC) cells with anodic porous alumina (APA) films as thickness of several 10 microns between two substrates was assembled. Optical characteristic and response speed of the cells were examined. Decay time responses of the cells were drastically improved. The reason of the improvement could be considered as following. The proportion which the LC material occupied in the vicinity of aligning surfaces relatively increased, and the cell thickness was equivalently due to thin as the result. This paper also describes the difference arising from several alignment methods.

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The rubbing treatment as a fabrication process of LCD is widely used now. Sometimes the rubbing treatment itself becomes a cause of the defect of the molecular alignment, because the rubbing cloth rubs the surface of the alignment film directly.
In this study, we investigate the defect of the vertical alignment film after the rubbing treatment. By means of the atomic force microscopy, surface profiler and micro-sampling mass spectrometry, assumed causes such as the contamination transferred by the rubbing cloth and the surface topology scratched by the rubbing cloth were studied.

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We have already reported that I-V (voltage versus current) characteristics of LC cells having a single-sided alignment layer become asymmetric waveform. We also have confirmed that asymmetric characteristics of I-V waveform changes by doping nanoparticles into LC or alignment layer. In this paper, we report that our proposed method could judge a polarity of mobile materials in LC layer from asymmetric characteristics of I-V curve by doping 4-Dimethylaminopyridine (4-DMAP) which is Lewis base into LC layer.

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We designed and synthesized new liquid crystalline compounds, 1,7,8-trifluoronaphthalene and 7,8-difluorochroman derivatives. For their preparation, we developed some important technologies such as a ring formation, a selective reduction, a selective fluorination and an aromatization. These compounds exhibited large absolute value of dielectric anisotropy. The 1,7,8-trifluoronaphthalene derivatives exhibited large birefringence, on the other hand, the 7,8-difluorochroman derivatives exhibited low birefringence. All of them are very useful for vertical alignment mode liquid crystal display (VA-LCD).

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Recently, we reported that the procedure to hold a nematic liquid crystal mixture at a temperature suitable for crystal growth after aging it at a temperature suitable for nucleation was an effective one to accelerate the crystallization. In this report, we deal with a nematic liquid crystal mixture where the temperature suitable for crystal growth is unknown. We also report that the aging time is an important factor for detecting the crystallization of nematic liquid crystal mixtures.

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It was reported that a 2,5-didecylphenyl derivative of imidazolium salt shows SmA phase. In this study, TOF technique was adopted to evaluate the carrier mobility. The resultant order of mobility is 10-3 cm2 V-1 s-1 in SmA phase and the temperature independent nature is found. Electronic hopping process in an ionic liquid crystal is discussed.

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2, 3, 6, 7, 10, 11-hexakis(4-alkyloxy-2, 3, 5, 6-tetrafluorobenzyloxy)triphenylenes (CnF4; n=6, 8, 10) were synthesized to study the mesomorphic phase transition behavior by polarized optical microscope, DSC and XRD techniques. It was found that CnF4s exhibit hexagonal columnar (Colh) phase with a wide range of temperature. In the Colh phase of C8F4, the positive carrier mobility was determined to be in the order of 10-2 cm2V-1s-1 by Time-Of- Flight (TOF) technique.

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An anthracene derivative exhibiting two different smectic A phases has been synthesized. We will discuss the change of the self-assembled structures and the photoluminescent color on this phase transition.

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A new series of liquid-crystalline materials based on pyridinium moieties was prepared. All the pyridinium salts exibited thermotropic liquid-crystalline columnar or cubic phases. The effects of the counterion species on the mesomorphic properties were examined. The electrochemical and photoluminescent properties of the pyridinium salts were also studied.

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Poly(a-fluoroacrylate)s bearing biphenyl groups with OC₈H₁₇, OCH₃, and CN end groups and 12 methylene spacers were synthesized by a radical polymerization. These phase transitions were studied by DSC and X-ray diffraction measurements, and POM observations. They were compared with those of polyacrylates and polymethacrylates with the same side groups, and the influence of a-fluorine atoms and end groups on the mesogenicity were examined.

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The Photoconductive Chiral Dopant for the Photorefractive FLC was developed and the effect was investigated.

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We prepared novel liquid crystal tetramers possessing cyanobiphenyl and phenylpyrimidine moieties, and investigated their phase transition behavior. The liquid crystal tetramers exhibited nematic (N) and smectic A (SmA) phases. X-ray diffraction measurements suggest that the SmA phase has an intercalated structure. We discuss the transition behavior of the novel designed tetramers in terms of their molecular shape.

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We prepared novel dumbbell-shaped liquid crystal oligomers in which two mesogens are connected via a flexible spacer, and investigated their physical properties using optical microscopy, differential scanning calorimetry and X-ray diffraction. Compound _I_ possessing an alkyl chain as the central group exhibited a nematic phase. On the other hand, compound _II_ possessing a perfluoroalkyl chain as the central group instead of the alkyl chain exhibited nematic, bilayer smectic A and intercalated smectic A' phases. We discuss their phase transition behavior in terms of the molecular shape.

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We have constructed the phase diagrams of a binary mixture system of an antiferroelctric and a ferroelectric liquid crystalline material for both thin and thick cells. These phase diagrams show a boundary almost parallel to the temperature axis between the smectic $C_{A}^*$ and smectic $C^*$ phases. The Sm$C^*$--Sm$C_{A}^*$ phase transition for a thin cell shows a large supercooling and a gradual transition near the boundary. Moreover, the thin cell shows a continuous evolution from antiferroelectric to ferroelectric state by increasing the electric field applied across the cell. This seemingly reflects the thresholdless antiferroelectricity. For explaining these phenomena on the basis of the frustration between ferroelectricity and antiferroelctricity, we measured the interlayer interaction energy by varying the concentration of the constituents in the binary mixture. The obtained interlayer interaction shows that the gradual phase transition and continuous evolution arise from the suppression of the solitary wave propagation by the surface effects.

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As continuation of the last announcement,this time , we analyzed three dimension model that introduces the liquid crystal intermolecular interaction in the layer as a mean field theory. In addition,It reports what influence the effect of the anchoring of the glass substrate exerts on a structural phase transition.

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Phase transition from SmCa* to SmC driven by an electric field is studied from a standpoint of discrete soliton concept. Under a condition of constant tilt angle, soliton density decreases to zero making a devil's staircase as the field is increased, and so an interaction between discrete solitons is repulsive but a range of the interaction is shorter than the one for the continuous solitons appearing at SmC*. Here, an effect of a variable tilt angle is studied. The interaction between discrete solitons is shown to be attractive due to a variation of the tilt angle and the transition changes to discontinuous.

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SmCa* and SmC* are ferroelectric and have helical structures, and both phase changes to SmC by an electric field. The transition for SmC* is interpreted as a soliton condensation. In contrast with SmC*, the soliton becomes a discrete type at SmCa* because a pitch is quite short. Here, we study how the transition to SmC occurs in the discretized description and how properties of the soliton accompanied with the transition change. It is shown that the transition to SmC is continuous and interaction between solitons is repulsive though the interaction is very short range. A field-dependence of a wave number makes a devil's staircase, and a free energy curve for the wave number is non-differentiable at any rational wave number. These properties are in contrast with those at the continuous description where both curves are analytic. Experimental facts on the apparent optical axis and polarization current are compared with the present results.

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The mesomorphic thermal stability of perfluoroalkylated triphenylenes is increased in the hexagonal columnar (Col_h) phase in comparison to that the corresponding alkoxytriphenylenes. Nevertheless, the charged carrier mobilities are comparable to the hydrocarbon homologues ( ~10^-4 cm²/Vs), and also the charged carrier mobilities show Arrehenius behavior. However, the regimes with different activation energies are recognized in the temperature range of Col_h phase, despite the phase transition was not observed in this regime with DSC and X-Ray diffraction. In this work, the temperature dependence of FT-IR spectra were measured to discuss on the dynamic aspect of molecules in the Col_h phase.

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During our development of the synthetic method of the title triple-deckers, we found that the triple-deckers were only the product just after the reactions, but that they decomposed into the corresponding double-deckers and metal-free derivatives after the column chromatography using chloroform as an eluent. This decomposition was revealed from the electronic absorption spectra. When the eluent was changed from chloroform to n-hexane, the pure triple-deckers could be successfully separated in high yields for the first time. The columnar mesomorphism of these triple-deckers was established.

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Our purpose is to synthesize the compounds having both donor and acceptor moieties and showing mesophase. We previously reported a donor-acceptor dyad discotic liquid crystal incorporated fullerene and phthalocyanine. However, there were problems that one, two and three Pc moieties were substituted to fullerene at the same time. Therefore, we have developed novel synthetic method to obtain the pure target dyad in high yield. Furthermore, the novel material showed columnar liquid crystalline property, and homeotropic alignment.

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In our previous work, we successfully synthesized a dyad of phthalocyanine(Pc) and [60]fullerene as a liquid crystalline compound having the donor-accepter system, and confirmed that it showed columnar mesomorphism and homeotropic alignment. In this work, we succeeded in the synthesis of novel donor-accepter dyads based on phthalocyanine-C60 which could be obtained in less synthetic steps and more easily purified. We established that they also show columnar mesomorphism and homeotropic alignment.

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Organic EL is announced in addition to the market competition of LCD and PDP, and in this confused fighting, the consumption of big-screen TV is hitting the wall. (To respond to more salves in the cutting price war, each panel maker has to challenge the yield improvement, the technical innovation, and pursuit of high throughput day-to-day.) Our company develops, manufactures, and provides various Dispense devices for the cell production process of LCD. This time, we would like to describe the seal dispensing device and the liquid crystal dropping device corresponding to liquid crystal dropping (ODF) process.

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We have some products for cell process of LCD which has top market share in world wide. This review focuses on UV sealant for one drop fill (ODF) process. UV sealant for ODF process easily makes a MURA trouble because of the UV sealant often contacts with liquid crystal before curing. This review explains some requirements of UV sealant for ODF process and the feature of our UV sealant.

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We designed and synthesized new liquid crystalline trifluoro-naphthalenes and difluorochromans with negative dielectric anisotropy for VA-LCD. The relationships between the properties and chemical structures are discussed. Some liquid crystal mixtures for VA-LCD applied to TV, mobile and sutomotive are prepared.

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[in Japanese]

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[in Japanese]

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A liquid crystal display for large size TV application requires high contrast ratio over a wide viewing angle range. In order to satisfy this requirement, an optical compensation using a retardation films has to be employed to suppress light leakage from the crossed polarizing plate.

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We have studied the dependency on color chroma and hue for allowable and optimal levels to color difference. The deeper the chroma, the wider the areas of optimal and allowable limits. The plot of each limit for deep RGB on the chromaticity diagram shows that the width for chroma is wider than that of hue area.

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We studied ergonomics requirements of color reproduction range of electronic displays and its shape in the chromaticity diagram through subjective evaluation for chroma using several pictures of objects or landscapes consisting of some memory colors with high chroma and various color hues. The result shows that optimal and allowable limits of yellowish, greenish and cyanic colors are lower than those of reddish, purplish and bluish colors. In addition, the differences of the limit values between each color on the xy-chart are smaller than those on the u'v'-chart.

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OCB-mode, that uses bend alignment, has merits such as fast response and wide viewing angle. For the practical use of OCB-mode, there are two important points, one is how to make bend alignment, and another is how to stabilize bend alignment. We have investigated about stability of bend alignment on dynamic driving, and we have found the anisotropy with the rubbing direction of the dynamic bend alignment stability.

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Newly proposed twisted alignment model reproduce optical properties of IPS LCDs more accurately than the conventional uniaxial model. By using the twisted alignment model, the maximum transmittance probable in IPS LCDs is estimated. The obtained results mean that the high transmittance comparable to that of the LC mode using electrically controlled birefringence effect is attainable in IPS-LCDs.

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[in Japanese]

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We observed spontaneous shape change of a uniaxially deformed liquid-crystalline elastomer composed of smectic main-chain liquid-crystalline polyesters with varying temperature in a cyclic heating-cooling process. Although the elastomer contracted about 115 % ((L-Liso)/Liso x 100) on heating up to the isotropic phase, the sample length recovered only 55 % on cooling to room temperature in the first heating-cooling process, the elastomer exhibited almost complete reversible deformation in the second heating-cooling process. By comparison of the sample observation with the X-ray analysis in the cyclic heating-cooling process, we recognized that the stain (L/Liso) is linearly coupled with the orientational order parameter S. In addition, the X-ray analysis implied that the cybotactic nematic state, in which the smectic clusters are stabilized in the oriented nematic-like domain, emerged after exposure to the isotropic phase.

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We have investigated the molecular mechanism of the spontaneous and reversible deformation of smectic elastomers during the isotropic-to-smectic phase transformation, by observing the shape change as well as an X-ray image of the elastomers for two different types of crosslinker, namely, a rod-like crosslinker and a hydroquinone-type crosslinker. The elastomer crosslinked by the rod-like crosslinker exhibits elongation corresponding to the change in the order parameter S during the isotropic-to-smectic phase transformation. As for another elastomer crosslinked by the hydroquinone-type crosslinker, which is too flexible to work as mesogen, the shape change is weakly coupled with the orientational order of mesogens. We conclude that the crosslinking topology attributed to the chemical constitution of the crosslinker predominantly controls the chain anisotropy of polymer network as well as the deformation behavior of smectic elastomers during the isotropic-to-smectic phase transformation. In addition, piezoelectric properties of a SmC* elastomer were investigated, focusing on the mechanical response to electric excitation in the monodomain sample. Elongation and shrinkage along the layer normal occurs by applying electric field perpendicular to tilting plane. The magnitude of the deformation, namely elongation and shrinkage along the layer normal, becomes maximum just below the SmA-SmC* transition temperature, because the deformation observed is associated with the contribution of the soft mode which is described as the tilt fluctuation of mesogens.

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Side chain liquid crystalline polymers with the chain backbone of substituted methylenes were more advantageous in order to realize well-ordered liquid crystalline phases, such as smectic phases, and for widening of liquid crystalline temperature range. Poly(fumarate)s carrying cyanobiphenyl mesogenic side chains were prepared and the phase transition behaviors of a series of novel poly(fumarate)s with different mesogen density and alkyl spacer were studied. Liquid crystalline phase window was expanded with increasing the mesogen density. The smectic phase structures formed by those asymmetrical polymers were discussed.

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Ion-conductive liquid crystalline (LC) physical gels were developed by combining an amphiphilic smectic liquid crystal, lithium salts and a low-molecular-weight gelator having azobenzene moieties. Ion-conducting behavior of the LC physical gels could be tuned via reversible structural changes in the composite structures induced by photoisomerization of azobenzene moieties.

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We synthesized novel photoresponsive dithienylethene derivatives with chiral moieties, and added them as chiral dopants into liquid crystalline (LC) conjugated polymers. The LC polymers showed a reversible change in chirality upon irradiations of UV and visible lights with an aid of thermal heating.

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We synthesized various poly(meta-phenylene) derivatives with alkyl side chains. They showed lyotropic liquid crystallinity based on self-assembled helical structure of the conjugated main chain in n-dodecane. Assignments of liquid crystalline phases and their concentration dependence were investigated by X-ray diffraction (XRD) and polarized optical microscope (POM)

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We synthesized photoresponsive chiral compounds, where both terminal sites of the photoresponsive dithienylethene moiety are linked with axially chiral binaphthyl moieties. The dihedral angle of the binaphthyl rings reversibly changed upon the photoisomerization between open and closed forms of the dithienylethene moiety. The chiral compound was added as a chiral dopant into nematic liquid crystal (N-LC) consisting of phenylcyclohexyl or cyanobiphenyl mesogen, giving a chiral nematic LC (N*-LC). Observation of polarizing optical microscope (POM) indicated that the N*-LC exhibited a helical inversion. The photoinduced switching behavior between N*-LC and N-LC was also observed.

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We synthesized aromatic conjugated polymer through introduction of ammonium groups into the terminal sites of the side chains. The polymer synthesized was soluble in water, and also in polar organic solvents such as methanol and dimethyl sulfoxide. The polymer solutions showed lyotropic liquid crystallinity in the certain concentration range. The liquid crystalline phases were characterized using polarized optical microscopy and X-ray diffraction.

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Structure and dynamics of an ionic liquid crystalline system, [C18min][CF3SO3], have been examined by molecular dynamics simulations with using an atomistic molecular model. Simulated smectic layer structure was rather diffuse than that was expected by the amphiphilic character of the system. A diffusion constant in the simulation was order of 10⁷cm²/s.

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Ionic liquid crystalline materials were synthesized and their phase transitions and orientational behavior were examined. The liquid crystalline properties of the ionic liquid crystals depended on a terminal group and a spacer chain length. The introduction of the ionic groups led to the liquid crystal formation and the enhancement of the thermal stability.

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Novel ionic liquid crystals based on hydrophilic polymers were synthesized. Their thermal and orientational properties were examined. The ionic liquid crystals exhibited fluid smectic (SmA and SmB), columnar, and cubic mesophases.

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Artificial phospholipids have been attracted a great deal of attentions, especially in the field of biochemistry, pharmacy, and material science, because design and synthesis of the ampiphilic phospholipids to form lipid bilayers would enable us to develop novel artificial ion channels, biological sensors, and so on. In the present research, we focused our attention on the design and synthesis of novel phospholipids having electro- or light-responsive calamitic mesogenic cores for the development of liquid-crystalline phospholipids. Induction of such properties into artificial phospholipids would be expected to develop electro- and light-responsive solid films, controlling ion and/or material transportation-insulation. In the present report, lyotropic liquid-crystalline phase behavior and structures of phospholipids with calamitic cores in aqueous medium were examined by using POM, DSC, and SAXS.

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Tilted monolayers composed of chiral liquid crystals (LCs) are known to exhibit the molecular collective precession under the transmembrane mass flow. This phenomenon has been successfully explained from the macroscopic point of view as a 2D-type "Lehmann Effect," while the microscopic mechanism has not been cleared yet. In order to reveal the individual molecular motion during Lehmann rotation, we calculated the torque on single isolated chiral LC molecule given by the flow, with the use of molecular dynamics (MD) simulation. The calculation result suggests that the collision of the flow molecules with the chiral LC molecule should cause the "molecular level" discriminative torque on each LC molecule.

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The rotational motions of fictitious axial-chiral LC molecules along their molecular long-axis were probed under trans-monolayer molecular flow of methane molecules by molecular dynamics simulations. We found that the coupling between the trans-monolayer molecular flow and the rotational motion of the monolayer molecules was more evident in this axial-chiral molecule than the MHPOBC molecule which we have previously studied.

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