High-pressure hot stage system for optical microscopy was developed for the in situ observation of texture of liquid crystals and polymers under hydrostatic pressures up to 300 MPa. The high pressure optical cell has two sapphire windows of 5mm in diameter at the top and bottom of the cell, and is heated from room temperature to about 250℃. The spherullitic growth of the crystal polymorph of a dimesogenic liquid crystal compound was observed clearly on cooling at 100 and 150 MPa.

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The nanosecond pulse pyroelectric technique has been applied to the measurements of the soft mode relaxation times on both side of the ferroelectric smectic A - C^* phase transition for chiral smectic liquid crystal. Inverse relaxation times seem to obey Curie-Weiss type behavior. "Tilt-viscosity" coefficient γ_θ has been calculated.

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Steady state current of nematic liquid crystal cells has been measured. The experimental results show that there is no thickness dependence for the sample cell using no aligning layer; and for the sample cell using poly-imide aligning layer, current depends on cell thickness: thicker rigion, current is proportional to inverse of thickness, and thinner rigion, proportional to quadratic of thickness.

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We have studied the dynamical coupling between the undulation fluctuation of the membrane and the Brownian motion of the latex particles in the latex doped lyotropic smectic liquid crystal. The order parameter decreases by increase in the latex concentration in the smectic liquid crystal, because the thermally excited isotropic Brownian motion of the latex particles does not prefer the ordered wall of layered structure. On the other hand, applying the electric field, due to the suppression of the undulation fluctuation stabilizes the lamellar structure by the anisotropic motion of the latex particles driving by the electric field. We also systematically investigated by DSC that this dynamical coupling affects to the thermodynamic L_α-L₃ phase transtion. By increase in the latex concentration, tne transition temperature increases, and width of the coexistence region become narrow range. This is because the latex particles can fluctuate more freely in the L_αα phase. This entropy difference leads the phase transition.

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We have investigated physical properties in multilayer film of CCH liquid crystal deposited on an interdigital electrode substrate with the Langmuir-Blodgett technique. As results of the dependences on film thickness, frequency and temperature of the permittivity, CCH-2 film has critical layer thickness(m〜30) and extremely different properties compared to the bulk film of the liquid crystal.

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A measurement method of the rotational viscosity (γ₁) with an analysis of the transient current of LC cell is very useful because of its simplicity comparing the rotating magnetic method. It has been already reported, but the elastic constants of LC are ignored in it. We propose new analysis expression which included them. It has been found that the γ₁ can be gotten easily and less error than the formermethod.

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Voltage dependence of AC conductivity was measured for LC cell. From the experimental results and theoretical consideration, it was found that the profile of AC conductivity in the suitable voltage region gives the information on the mobility of ions in LC cell and that AC conductivity for higher voltage than the threshold gives the information on ratio of the mobility for both directions , parallel and perpendicular to the long axis of LC molecule.

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The flicker minimizing method has been proposed in order to measure the residual DC voltage. However the flicker minimizing method has some problems; A)measurement results vary by test person, B)difficult to obtain good reproduction in measurement results even by single test person. We proposed the dielectric absorption method in order to measure the residual DC voltage in 1996. We found that the residual DC voltage depended on the thickness of alignment layers. The dielectric absorption method is a very simple measurement method. We have confirmed a strong correlation between the results of the flicker minimizing method and those of the dielectric absorption method.

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We investigated the internal voltage of the liquid crystal panel. Due to the dielectric absorption properties of the liquid crystal panel, the nematic to cholesteric phase transition is significantly suppressed, resulting in the wide and stable electro-optical hysteresis effect. The analysis of the dielectric absorption voltage in the liquid crystal panel is considered to suggest a certain key to clarify the surface anchoring effect in terms of the dynamic switching properties.

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Model LCD cell sealed with an epoxy resin were exposed to high temperature and high humidity test conditions. A remarkable voltage-holding-capacity (VHC) drops have been observed near the sealing edge of LCD cells by the exposure for a few hundred hours. The cause of VHC drops has been examined by microanalytical techniques like FT-IR-microspectroscopy and microsampling mass spectrometry. Carboxylic acid and amine have been detected from the interface between liquid crystal and polyimide alignment film near the sealing edge. The existence of these chemical species will be discussed from the viewpoint of VHC drops.

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Various kinds of display failure are known around the injection corner of Liquid Crystal Display (LCD) cell. Chromatogram phenomenon ( effect ) is a well known display failure observed after the injection process of liquid crystal. It is said that impurities contained in liquid crystal are absorbed on the alignment film around the injection corner in a form of chromatogram pattern. This kind of failure has been examined microanalytical technique like FT-IR-Microscopy and Microsampling MS.

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A sealing resin of LCD cell must have property to protect liquid crystal from environment. We have investigated the effect of the hot water on the sealing resin and we have found a small quantity of the dissolvable substance from the sealing resin into the hot water. We have discussed further relationship between the amount of this substance and LCD characteristics.

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We have developed a software that can predict the inlet flow of a nematic liquid crystal into a liquid crystal cell, using the Leslie-Ericksen equations with the Hele-Shaw approximation. As an example, we have selected a liquid crystal cell with 75 mm in length, 100 mm in width and 10 μm in thickness, and presented transient free surface positions of MBBA with the anchoring angles of -90 and 0 deg.

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It is expected that the panels which consist of two adhering glass plates with rib have better anti-shock and anti-press characteristics than those comprised of two glass substrates in which silica beads dispersed as spacer. In this forum, we will present about anti-shock and anti-press characteristics of some of those panels which we developed. The ribs of these studied panels consist of positive photoresist which is commercially available, and the panels are filled in with (A)FLC, such as SCE9(Hoechst), CS1013, CS1014, CS1027 and CS4000(Chisso Corp.). All the panels are treated with temperaturegradient-cooling method that we had developed to be uniform phase(SmC^* or SmC_A^*) and orientation of (A)FLC in those. In order to compare the anti-press characteristic of the panels, the minimum antipressure (Pmin) causing zigzag or line-like defects and the maximum anti-pressure (Pmax) at which defects would disappear completely within 1 minute following termination of press are measured with push-pull scale. In result, it is found to maintain the uniformity of the phae and the orientation of (A)FLC such as CS1014, CS1027 and CS4000 in the panels, even if the pressure of 100 Ncm^-2 applied on those.

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Electro-optical properties of fluorinated liquid crystals with a 3-substituted benzene ring have been measured. The temperature dependence of dielectric aisotropy, splay elastic constant are dicussed. The fluorinated liquid crystals with a bend structure are useful to reduce threshold voltage(Vth) and to improve the temperature dependence of Vth for STN-LCD.

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A frequency dependence of dielectric anisotropy for liquid crystals with positive or negative dielectric anisotropy has been investigated. Even for a liquid crystal with negative dielectric anisotropy, strong frequency dependence was observed. From the results, we have improved frequency dependence of dielectric anisotropy for STN mixtures.

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Trans-4.4' -bis(alkyl) difluorostilbenes were reported to be superior LC compounds with low viscosity and high △n except for having low UV-stability. We have attempted to introduce of fluorine to the benzene ring or to substitute one of the two benzene rings for cyclohexane ring for obtaining LC compounds with higher UV-stability. It was found that the former compounds were characterized by lower viscosity and the latter compounds showed large K33/K11 values. The mixtures for STN-LCDs with fast response time were developed using these new materials.

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We observed the alignment of liquid crystals with polar linking and terminal groups on a glass substrate covered with an aminosilane coupling agent by using a polarizing microscope. The liquid crystals used were two types of cyanobiphenyl compounds, 5CB having a cyano group as a terminal substituent and ME7N having a terminal cyano group and an ester linking group between the two phenylene rings. For 5CB the director aligned perpendicular to the amino-covered substrate resulting in a monodomain, while ME7N exhibited a number of domains. In each domain the director aligned parallel to the substrate. These results suggest that the interaction between the polar groups in the liquid crystal and those on the substrate surface plays an important role in the liquid crystal alignment.

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It has been reported that homogeneously aligned LC layers could be obtained by shearing the LC materials onthe substrates with a glass rod. In this paper, we tried to get some pretilt angles in LC cells treated by such a shearing method. Aligning properties on the four kinds of polyimide (PI) materials which gave different pretilt biases of about 7 to 14 degrees if rubbed were investigated. We could obtain pretilts of 0.5 to 1.5 degrees on these PI layers by the shearing method. The LC director is parallel to the shearing direction and pretilts out of the substrate surface in the opposite azimuth direction to that the rubbing. By using a UV curable LC system, a decreasing tendency of the pretilt angle with time could be suppressed.

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Novel liquid crystal (LC) alignment layers using polyamide films have been investigated. We propose three type of polyamide alignment films. All of them show relatively low pretilt angle and very high thermal stability of LC orientation and its pretilt angle. It is considered that such property is related to the thermal stability of uniform orientation of polymer itself. In addtion, one of them has a characteristic that the retardation on polymer surface induced by rubbing is very large. Furthermore, it was found that, by use of polyamide alignment films, good orientation of suface stabilized ferroelectric LCs is obtained.

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We have investigated a series of polyimides on alignment properties of ferroelectric liquid crystals. One of the properties of these polyimide alignment films is low-pretilt angle with nematic liquid crystals. These polyimide alignment films showed a high uniaxial orientation with the rubbing treatment. In this study, we discuss the relationship between the high uniaxial orientation of polyimide alignment film and the alignment of ferroelectric liquid crystals.

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Surface anchoring effect on the electro-optical performance of a lateral field driving Liquid Crystal Display has been studied both theroretically and experimrntally. With different alignment treatment, including polymer buffing and photoalignment, the boundary coupling condition of surface liquid crystals has been changed. The results of the electrooptic switching characteristics examination of the device cells, demostrated that the voltages giving maximum transmittance decrease with decreasing the azimuthal surface anchoring energy.

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This paper describes the mechanism of pretilt angle generation. The pretilt angle is generally supposed to depend on the cubic molecular structure and the polarity of the alignment layer surface. However, we often fail to get the original pretilt angle in the case of practical panel fabrication. This shows there is some cause reducing pretilt angle. We find the uneven surface condition of the alignment layer influences the pretilt angle, and examine the relationship of the roughness of alignment layer surface and the pretilt angle. We conclude the pretilt angle depends on two elements. The first element is the cubic molecular structure and the polarity of the alignment layer surface, and the other element is flatness of alignment layer surface.

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Surface hydrogenation reaction was perfomed to distinguish the mechanism of the photoalignment using poly(vinyl cinnamate)(PVCi). The reaction makes it possible to remove any plausible surface ordering of cinnamate side groups which may happen during the photoalignment process while the generated photoproducts are still intact. After considering the alignment and the azimuthal anchoring energy of the hydrogenated PVCi/E7 cells, it was identified that the alignment of LC molecules is mainly induced by the photoproducts.

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We have investigated the alignment phenomena of some liquid crystals, which have different Δ ε values, on the newly synthesized polycinnamate according to the linearly polarized UV exposure method. The liquid crystals having positive Δ ε value aligned homogeneously to the direction perpendicular to the transmission axis of sheet polarizer used in our experiment, but those having negative Δ ε value aligned homeotropically to the direction parallel to the transmission axis of polarizer.

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In the cell without rubbing, singular points of schlieren textures grow at the boundary of the pattern. Under applied voltage, reverse tilt disclination grow from the singular points. In the cell with rubbing on the finely patterned substrate, mono domain alignment is obtained. Generation of the reverse tilt disclination is the same as that of the cell without rubbing and is depends on the pattern shape and rubbing direction.

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The photocontrol of LC alignment was achieved using the surface-modificated LC cell with photoreactive molecules, called as command surface. In the photocontrol mechanism, a reorientation process with continuous isomerization of the photoactive molecule was proposed to be essential. To investigate effects of geometrical photoisomerization for LC alignment, we used diphenylacetylene (DPA) as a photoactive molecule with no photoisomerization. Our previous study shows that the re-orientation of chromophores at the LC-substrate interface play a crucial role in the photocontrol of LC alignment. In this study, 11-(4-(2-phenylethynyl)phenoxy) undecanoic acid (11DPA) was used as DPA moities and formed selfassembled complexes with poly-allylamine (PAA) on a substrate. The uni-directional LC alignment was observed on the LC cell using a substrate with DPA desity of 1nm²/molecule. However. no photoalignment was obsered in the case of a substrate with high DPA density (0.4nm²/molecule). Polarized absorption spectra of dichroic dye in the LC cell revealed that the direction of LC alignment was perpendicular to the LPL electricvector. In DPA substituted polymethacrylate films exhibited the parallel LC alignment to it. The reason for these differences of LC alignment direction was considered as a difference in photochemical reactions of DPA moieties.

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The alignnaent behavior of liquid crystal (LC) on the surface of four types of polyimide (PI) films exposed to linearly polarized ultraviolet (LPUV) light was investigated with polarizing microscopy.We found that the homogeneous alignment of the LC was induced. The alignment ability of the PIs was strongly depen dent on the chemical structure of PIs and increased with increasing of the absorbed energy of the PIs. The change in the PI structure after UV exposure was evaluated by UV-VIS spectroscopy. The spectra showed that the absorbance change of the aromatic PIs is much smaller than that of the PI with an alicyclic dian hydride when uniform homogeneous alignment of the LC was caused. In particular, the change in the absorbance of the aromatic PI with ether group was only 0.05%. The results mean that the aromatic PIs are more favorable as a photosensitive alignment layer than the PI with an alicyclic moiety and the homogeneous alignment of the LCs can be induced without significant destruction of the chemical structure of PIs.

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We developed a convenient method to prepare command layers for the photocontrol of liquid crystal alignment by surface-selective adsorption of 4-(10-aminodecyloxy)-4'-butylazobenzene (4AzA) on poly(acrylic acid) films. The surface morphology of polymer films was critically affected by the concentration of the azobenzene adsorbate in hexane, and a 2.5×10^-5 mol dm^-3 solution gave an azobenzene monolayer of a surface density of 2 molecules nm^-2 without any modification of the surface morphology of polymer films. The surface density of the azobenzene was controlled by binary systems consisting of 4AzA and n-octadecylamine. Irradiation with an LC cell using a plate of the azobenzene monolayer generated homogeneous alignment with an excellent optical quality and a high resolution power. It was found that a minimum exposure energy of the actinic polarzed ultraviolet light required for the liquid erystal alignment photocontrol was dependent on the surface density of the azobenzene chromophore. No photoresponse was observed for average densities of 4AzA smaller than ca. 0.7 molecules nm^-2. The smaller the density of the chromophore on polymer film was, the faster the photoreorientation of the liquid crystal effectively took place.

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We synthesized new liquid crystal compound, 4-n-alkylcyclohexylbenzyl 2'-perfluoropropoxy-2',3',3',3'-tetrafluoropropyl ether(ACPTE) and 4-n-alkylbicyclohexylbenzyl 2'-perfluoropropoxy-2',3',3',3'-tetrafluoropropyl ether(ABPTE), and investigated their liquid crystalline phase transition and electro-optical properties. ACPTE and ABPTE showed smectic A, B and E phases and both are found to act as one component lowering the refractive anisotropy in ZLI-1132 solvent.

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We have investigated a phase separation process induced by a photo-polymerization in the homogeneous solution which is composed of the UV-curable monomer-mixture and 5CB as liquid crystal. The phase diagram is obtained by the microscopic observation with using crossed polarizer and phase difference, It is turned out that the phase separation temperature can be distinguished from the Nematic-Isotropic transition temperature. We have confirmed the experimental results that critical points on the phase separation curve are shifted upward at right-hand side during UV-light exposure. In the phase separation process, the periodicity in the structure of the polymer/LC composite films is depended on the phase diagram. The periodicity occurred by spinodal decomposition is observed less than 75mol% due to the existence of single peak in the light scattering profiles.

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Combinations of liquid crystals and polymer materials are investigated to enhance the transparencyin the memory-state of polymer dispersed liquid crystal (PDLC) cells. Refractive indices of each material influence on the transmittance in the memory-state, as well as that in the off-state. The cell thickness and concentration of the liquid crystal in the PDLC cell are also discussed.

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Mesomorphic characteristics and bistable electro-optical switching characteristics driven by a.c. electric fields with different frequencies were investigated for the (liquid crystalline copolymer with terminal trifluoromethoxy groups: LCcoP-F/low molecular weight nematic liquid crystals : nematic LCs) composite systems in a smectic state. The novel LCcoP-Fs were synthesized through poly(hydrosilation) reaction in order to improve the switching speed due to a reduction of viscosity of the binary composite systems. The LCcoP-F with short spacer length m = 3 showed a smectic phase. On the other hand, the LCcoP-F with long spacer length m = 6 showed crystalline and smectic phases. The binary composite systems composed of the LCcoP-F with the higher fraction of than 30 wt% and the nematic LCs with terminal fluoro groups showed compatible smectic phases at room temperature. The binary composite systems showed the higher speed electro-optical switching as well as the stable memory effect at room temperature.

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We have reported the thermal properties of the side-chain type liquid-crystalline polyacrylates introduced a siloxane bond to the spacer part. In this paper, the dynamic behaviors of P-1 〜 P-7, as shown in table, were investigated by dielectric relaxation spectroscopy over the frequency range 10 〜 10⁶ Hz at different temperatures (above room temperature). For all samples, the dielectric loss peak arising from δ-relaxation process was detected. As a result of the fitting by Fuoss-Kirkwood function, distribution parameter, β, of the siloxane-spacer type, SS, was larger than that of the alkylene-spacer type, AS, at the same reduced temperature,T_red (=T/T_g). By using the critical frequencies, f_m, of each polymer at various temperatures, 1n f_m-1/T and 1n f_m-1/T_red were plotted. The dielectric relaxation time, τ_δ(=1/2πf_m), of SS was longer than that of AS at the same T_red. Since the introduction of siloxane linkage into a spacer chain decreases the T_g of a polymer, the viscosity would relatively increase at the same T_red. On the contrary,τ_δ of SS was very shorter than that of AS at the same absolute temperature. The values of the apparent activation energy of SS and AS were estimated as about 80 kJ-mol^-1 and about 100 kJ-mol^-1, respectively. Therefore, it is suggested that a siloxane-spacer unambiguously enhances the mobility of side-chain by decreasing T_g.

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A polymer-dispersedliquid crystals (PDLC) provides novel display devices which take advantages of the scattering mode. It has been known that the photocontrol of in-plane liquid crystal alignment is achieved by linearly polarized light (LPL)irradiation of azobenzene polymer thin films. In the present study, we investigated the photocontrol of liquid crystal alignment in PDLC containing azobenzene chromophores.PDLC cells were fabricated by' heating of mixtures of an azobenzene monoacrylate monomer, a diacrylate and a nematic liquidcrystal which was sandwiched between two silicaplates.Dichroic absorption of azobenzene chromophores and birefringence were observed when 436 nm-LPL was irradiated because of the anisotropic orientation of both azobenzene chromophores and liquid crystals. Properties of this type of photosensitive PDLC was also discussed.

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We prepared polymer-dispersed liquid crystals containing azobenzene derivatives as a photoresponsive molecule and evaluated their optical response induced by photoirradiation. The optical property of the films was found to be affected by the compositional ratio of each component. The composite film with optimal compositional ratio showed a strong light scattering in an initial state. The reversible change between a light-scattering state and a transparent state was achieved by alternating irradiation with UV light and visible light. This phenomenon is ascribed to nematic ⟷ isotropic photochemical phase transition induced by trans ⟷ cis photoisomerization of the azobenzene molecules.

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A class of liquid crystals that has recently generated considerable interest is that of the liquid crystal dimers. Whereas the more familiar monomer systems generally comprise of a single rigid unit connected to a flexible chain, the dimers have two mesogenic groups conneeted with a flexible spacer. This simple extension allows the creation of a whole group of liquid crystal materials that possess properties fundamentally different to their monomer constituents, properties that resemble to a greater extent those of semi-flexible main chain liquid polymers. The majority of dimer systems synthesised and studied so far can be classed as symmetric dimers; i.e. the two mesogenic groups are identical. However, a second group exists where the dimers have different mesogenic groups, the so-called non-symmetric dimers. This presentation is concerned with the non-symmetric α-(4-cyanobiphenyl-4'-yloxy)-ω-(4-n-alkylanilinebenzylidine-4'-oxy) alkanes, CBOnO.ms[1].

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We studied the layer structures of the polymer-stabilized ferroelectric liquid crystal (PSFLC) with grayscale memory using an X-ray diffraction meter and a polarizing microscope. In the PSFLC fabricated under ultraviolet light irradiation, the inclination angle of smectic layer in the chevron structure decreased with aligned low-concentration polymer when the irradiation intensity increased. A unique microscopic striped texture, in which smectic layers were slightly deviated from normal of the rubbing direction, could also be controlled by dispersing the polymer. This polymer anchoring is concerned with the forming of small liquid crystal domains with different threshold voltages for bistable switching.

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We synthesized methacrylate copolymers comprizing 2-cinnamoylethozy-4-biphenyloxyhexyl group and 4-cyanobiphenyloxyhexyl group. All synthesized copolymers showed a liquid crystallinity and can be photo-crosslink by UV irradiation. Linearly polarized (LP) UV irradaition on the eopolymer films resulted in an optical anisotropy of the film, especially at the LC temperature of the copolymers. The optical anisotropy were investigated by polarized UV and FT-IR measurements. The direction of the orientation of the mesogenic group was found to be parallel to the electrical direction of the incident LP-UV light. The reorientation of the non-reacted mesogenic group is occur during the LP-UV photoreaction. The induced birefringence Δn is in the range of 0.02-0.07. Because of the high photo-crosslinking, the LP-UV photoreacted film shows the orientational stability.

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Polymer Cell-Wall Type Liquid Crystal (PCW-LC) light shutter has been developed for liquid crystal-polymer complexes (LCPCs), utilizing the light scattering of cholesteric focal conic texture. This type of liquid crystal light shutter is a energy saving type because of non-polarizer usage. When this type of light shutter is utilized for reflection type liquid crystal display, the saving of energy will become great. At first, an apparatus which can measure reflected light intensity against angle has been constructed.

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Polarization switching behaviors in the polymer-ferroelectric liquid crystal complex are investigated in terms of a polymer stabilized ferroelectric liquid crystal system. While spontaneous polarization decreases monotonously with increase in the UV curable origomer, both permittivity and optical response time exhibit maxima. Also the dynamic results from a polarization modulated spectroellipsometer suggest that the polymer stabilized effect in this particular system is concerned with not the layer structure stabilization but the stabilization of the polarization structure itself

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Polymer-stabilized SSFLC (PS-SSFLC) cells using a ferroelectoric liquid crystal doped with photo-curable liquid crystalline monomers have been successfully fabricated. The phase transition temperature of a ferroelectoric liquid crystal doped with photo-curable liquid crystalline monomers is studied by dielectric constant measurements. Indicating successive reduction of the phase transition temperature of the FLC doped with increasing the doped monomer concentration. PS-SSFLC cells fabricated by UV exposure to photo-curable monomer-doped FLC in a SmA phase show the capability of analogue grayscale operation with high switch speed characteristics.

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Transient scattering mode (TSM) at the instant of polarity reversal of applied voltage in the chiral smectic C phase of ferroelectric luquid crystals (FLCs) using uniformly aligned cell has been studied. The scattered light in the TSM using uniformly aligned cell has an azimuthal dependence. Polarizing microscope observation of FLC at the instant of polarity reversal of applied voltage has been performed. Parallel stripes have been observed in the microscope figures. The direction of the stripes is tilted to the smectic layer and the tilt direction of the stripes depends on the polarity of applied voltage.

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Several homologues of perfluorinated phenyl pyrimidine liquid crystals have been synthesized and their properties evaluated. The fluorination extent of the achiral terminal chain was found to affect both the phase diagram and the physical properties greatly. The mesomorphic properties of this novel liquid crystals are reported and the effect of the fluorination extent are discussed. Also, a novel liquid crystal with a perfluorinated linkage are synthesized and its properties are reported.

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Relation between polar component of surface tension and director distribution in surface-stabilized ferroelectric liquid crystal cell has been investigated. Hybrid type cells, each side of inner surface has same pretilt angle and different polar component of sturface tension, show excellent uniform alignment.

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In order to to clarify the molecular reorientation behavior induced by polarization inversion for ferroelectric liquid crystal, an electric current along the direction perpendicular to both the electric field and the smectic layer normal was measured for the cell with a thickness of 50 μm. The electric current curve against time upon the application of an a.c. electric field with a form of triangular wave showed a peak originate from polarization inversion and the sign of the peak value of the current changed from + to - or from - to + corresponding to the polarity inversion of the electric field. This indicates that the liquid crystal molecules homogeneously rotate in the same direction upon the polarity inversion. The rotational direction was also clarified under polarized optical microscope observation as the director change during the polarization inversion in the case of the free standing film.

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We have investigated the molecular dynamics in the chiral smectic phases of an antiferroelectric liquid crystal, (S)-MHPOBC, by means of solid-state¹³C NMR spectroscopy with CP/MAS and MASGHD techniques. In the CP/MAS spectra on heating, the half-width of an aromatic peak increases with increasing temperature in crystalline phase until it attains a maximum at about 75℃, and decrease in smectic phases. Assuming that the observed line broadening of MHPOBC occurs under the condition of ω₁・τ〜1, where ω₁ is a contact time and τ is a correlation time, the crrelation time (τ) of the molecular motion for the core part is estimated to be about 10^-6s.

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The heat capacity has been measured near the Sm-A-Sm-C_α^*-Sm-C^* phase transition in antiferroelectric liquid crystal MHPOBC for samples of different optical purities. A high presicion ac calorimeter has been used for the measurement. When the optical purity is high, the Sm-A-Sm-C_α^* transition remained second-order. On the other hand, the Sm-A-Sm-C^* transition remained almost tricritical for mixtures slightly off the racemic point.

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Complete assignment of the ¹³C-NMR lines has been established for the antiferroelectric liquid crystal MHPOBC. INADEQUATE in the isotropic phase, analysis of the alignment-induced shifts and their temperature-dependences, cross-polarization efficiencies, chemical substitution, i.e., trifluorination of the 1-methyl group, were employed.

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