• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.97-100
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• 2005

The recent Bistable Nematic ($BiNem{(R)}$) LCD technology presents long term bistability, high level passive matrix multiplexing and high optical quality. The BiNem device, based on anchoring breaking, needs specific low anchoring strength materials - alignment layers and liquid crystal mixtures. We present here our approach to develop nematic mixtures with wide enough temperature range and low zenithal anchoring energy.

• Journal of Information Display
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• v.6 no.3
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• pp.1-5
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• 2005

The recent Bistable Nematic ($BiNem^{(R)}$) LCD technology presents long term bistability, high level passive matrix multiplexing, gray levels capabilities and high optical quality. The $BiNem^{(R)}$ device, based on anchoring breaking, needs specific low anchoring strength materials - alignment layers and liquid crystal mixtures. We present here our approach to develop nematic mixtures with wide enough temperature range and low zenithal anchoring energy.

• Macromolecular Research
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• v.15 no.5
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• pp.396-402
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• 2007

The dielectric properties and various pattern-forming states of dual-frequency material in a nematic phase, as well as its mixture containing low concentrations of reactive monomers, are reported. The dielectric relaxation behaviors of nematic MLC 2048 are presented and compared to its mixture containing both mesogenic and nonmesogenic reactive monomers. The sign-inversion frequency of the dielectric anisotropy was significantly shifted on the addition of small amounts of the reactive monomers. However, all three mixtures used in this study essentially exhibited the same field-induced instabilities at different frequencies and voltage domains of the applied electric field. A broad band of modulated states were found to exist above a critical voltage and within a voltage dependent frequency band in the vicinity of the sign-inversion frequency, $f_I$, of the dielectric anisotropy. As the $f_I$ of the mixtures shifted, so did the bands of the modulated state of the different mixtures and the temperatures, which were well matched with the measured $f_I$ value.

• Journal of Information Display
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• v.2 no.3
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• pp.32-38
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• 2001

The most important parameter for TV application of LCD is a fast switching time for the display of moving image. To achieve faster switching time, the novel LC single materials with large dielectric anisotropies ($16{\sim}20$), high clearing temperatures ($195.5{\sim}237.4^{\circ}C$), broad nematic ranges (up to 169.9 $^{\circ}C$) and high birefringence ($0.254{\sim}0.2200$) were developed. KUR-series LC mixtures blended these single materials having significantly higher clearing temperatures and dielectric anisotropy values compared with conventional LC mixture. Especially, their clearing temperatures are $10{\sim}30^{\circ}C$ higher than their host mixture. These LC mixtures showing about lOms of high-speed switching time in Tv/Monitor of TFT LCD, is short enough to be addressed in a single time frame of 60Hz (16.7 ms). The threshold voltage $V_{th}$ was low enough to operate at a driving voltage of 5 V. The VHR values were found to be high enough for TFT-LCD in wide temperature range. Our novel LC mixtures are suitable materials for the inclusion in to LC mixtures for TV application of TN-LCD

• Polymer(Korea)
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• v.35 no.5
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• pp.493-498
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• 2011

Reactive mesogens were used to prepare photo-cured liquid crystal films in which orientations of liquid crystal molecules were preserved by crosslinked networks of cured reactive mesogens. The molecular orientations of liquid crystal mixtures of photo-reative mesogens and non-reactive nematic liquid crystals were studied and compared before and after curing reactions. The effects of temperature and the amount of the non-reactive nematic liquid crystal in the mixture on birefringence of the liquid crystal films were investigated. It was found that optical compensation films with different birefringence could be prepared by controlling the amount of the nematic liquid crystals in the reactive mesogen mixtures.

• Transactions on Electrical and Electronic Materials
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• v.13 no.1
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• pp.2-5
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• 2012

We have designed, synthesized, and evaluated the physical properties of some high birefringence (${\Delta}n$) isothiocyanato biphenyl-bistolane liquid crystals. These compounds exhibit ${\Delta}n^-$ 0.4-0.7 at room temperature and wavelength $\lambda$=633 nm. Laterally substituted short alkyl chains and fluorine atom eliminate smectic phase and lower the melting temperature. The moderate melting temperature and very high clearing temperature make those compounds attractive for eutectic mixture formulation. Several mixtures based on those compounds were formulated and its physical properties evaluated.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.498-499
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• 2002

In In order to develop liquid crystal mixtures of high response time and high nematic-isotropic transition temperature ($T_{NI}$) for LCD-TV application, novel liquid crystal molecules with a fluoro-isothiocyanate moiety were synthesized. They showed remarkably high $T_{NI}$ over 200 $^{\circ}C$, wide mesophase range of 170 $^{\circ}C$, high dielectric anisotropy of 14 and high optical anisotropy of 0.19. New LC Mixtures of the high $T_{NI}$ ($85{\sim}100 ^{\circ}C$) and fast response time ($8{\sim}10ms$) were blended with the novel fluoro-isothiocyanate containing LC molecules, phenylcyclohexanes, bicyclohexanes and ester compounds. It was also studied on optimum pitch of liquid crystal for high speed twisted nematic LCD-TV applicaton. The LC mixtures show a fast speed of the below one frame rate in real 17" TV panel.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.413-414
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• 2002

In In order to develop liquid crystal mixtures of high response time and high nematic-isotropic transition temperature ($T_{NI}$) for LCD-TV application, novel liquid crystal molecules with a fluoroisothiocyanate moiety were synthesized. They showed remarkably high $T_{NI}$ over 200 $^{\circ}C$, wide mesophase range of 170 $^{\circ}C$, high dielectric anisotropy of 14 and high optical anisotropy of 0.19. New LC Mixtures of the high $T_{NI}$ (85${\sim}$100 $^{\circ}C$) and fast response time (8${\sim}$10ms) were blended with the novel fluoroisothiocyanate containing LC molecules, phenylcyclohexanes, bicyclohexanes and ester compounds. It was also studied on optimum pitch of liquid crystal for high speed twisted nematic LCD-TV applicaton. The LC mixtures show a fast speed of the below one frame rate in real 17" TV panel.

• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.353-357
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• 1986

Mutual miscibility between thermotropic, nematic compounds with two terminal mesogenic units and a central spacer was studied by differential scanning calorimetry (DSC) and on a polarizing microscope. It was found that the isomorphous, nematic dimesogenic compounds with wide variety of structures are miscible in mesophases with each other over the whole range of composition and that Schroder-van Laar equation almost correctly predicts the melting temperature and composition of eutectic mixtures. There was a pair of compounds which were exceptional and did not form a eutectic mixture and, instead, revealed a monotonous change in melting (T$_{m}$) and isotropic transition temperatures (T$_{i}$) as the composition of the mixture was varied. The compounds were of almost same structure in shape and seemed to undergo formation of solid solution.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.260-262
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• 2003

We report several difluoro isothiocyanato tolane-based liquid crystal (LC) singles having a high optical birefringence. Several eutectic mixtures are formulatd using these LC singles exhibiting a wide nematic phase range and high birefringence. We will report the physical properties of and photochemical stability of these new eutectic mixtures.