In this study, two alignment methods were used to create a Fringe-Field Switching (FFS) mode liquid crystal device using an organic thin film (polyimide: PI) as an alignment layer. In addition, the electro-optical (EO) characteristics of the liquid crystal device manufactured in this way were investigated to evaluate the feasibility of mass production application of the technology. In general, the photo-alignment method using unpolarized ultraviolet rays can obtain a relatively low pretilt angle, so a liquid crystal device in FFS mode, which is a driving mode of the liquid crystal device that reflects the characteristics of liquid crystal alignment, was manufactured, and the liquid crystal has a high reactivity with the alignment film. Considering this, nematic liquid crystal (NLC) was used. In addition, in order to improve the misalignment, it was observed whether more stable orientation occurred by irradiating ultraviolet rays for an additional 1 to 3 hours in the aligned state. As a result of the experiment, it was found that NLC alignment occurs through a photodecomposition reaction caused by unpolarized UV irradiation oblique to the PI surface. In addition to the existing orientation method, UV irradiation was used to achieve a more stable orientation state and stable V-T curve and response characteristics. With liquid crystal alignment completed, more stable orientation characteristics and EO characteristics at the mass production level were obtained through additional UV irradiation for 3 hours. This method can further stabilize the orientation stability caused by existing UV irradiation through an additional process.

We investigated the cause of liquid crystal alignment when an ion beam is irradiated to the liquid crystal(LC) alignment film for liquid crystal alignment. We investigated liquid crystal alignment in response to changes in ion beam (IB) incident angle and electro-optical (EO) properties of twisted nematic (TN)-liquid crystal displays (LCDs) on polyimide (PI) surface. X-ray photoelectron spectroscopy(XPS) analysis showed that the C=O chemical bond strength decreased with changes in the IB incident angle, while the C-O chemical bond strength increased. Therefore, it was found that the dipole-dipole interaction between C-O chemical bonds and LC molecules has a chemical ordering effect. Good and uniform alignment of nematic LC was observed on the liquid crystal alignment layer surface by IB irradiation, and good EO properties of IB aligned TN-LCD were achieved on the liquid crystal alignment layer surface.

We used Brewster’sLaw to examine the mechanism of liquid crystal(LC) alignment on anorganic insulation layer when subjected to ion-beam irradiation. Brewster’s Law implies that the maximum rate polarized ray on a slanted insulation layers on the substrate and it illustrates the dependence of polarization and the mechanical structure on the ionbeam irradiation process. The pretilt angle of nematic LCs on the organic insulation surface was about 1.13° for an ionbeam exposure of 45° for 1minute at 1800eV. This shows the dependence of LC alignment on the polarization ratio in a slanted organic insulation layer.

Using UV nanoimprint lithography(UV-NIL), 1-dimensional(1-D) pattern structures were fabricated on a hybrid mixture thin film of lanthanum oxide and a UV-curable resin. 1-D pattern on a wafer fabricated by the laser interference lithography was transferred to polydimethylsiloxane and this is used as a mold of UV-NIL process. Conducting an X-ray photoelectron spectroscopy, C 1s and La 3d spectra were analyzed, and it was confirmed that hybrid thin film was successfully deposited on glass substrate. Also, transferred pattern structure was observed by using an atomic force microscopy. Through this, it was revealed that agglomerations between 1-D pattern were increased as UV irradiation time increased and this phenomenon disrupted the quality of NIL process. Additionally, liquid crystal(LC) cells with patterned hybrid thin films were fabricated and LC alignment performances were investigated. Using the polarizing optical microscopy and the crystal rotation method, LC alignment state and pretilt angles were observed. Consequently, the uniform homogeneous LC alignment was achieved at UV irradiation time of 1min and 3min where high resolution pattern transfer was observed.

Using lanthanum zinc oxide (LZO) film with the ion-beam irradiation, uniform and homogeneous liquid crystal (LC) alignment was achieved. To fabricate the LZO thin film on glass substrate, solution process was conducted as a deposition method. Cross-polarized optical microscopy (POM) and the crystal rotation method reveal the state of LC alignment on the ion-beam irradiated LZO film. Between orthogonally placed polarizers, POM image showed constant black color with regular transmittance. Furthermore, collected incidence angle versus transmittance curve from the crystal rotation method revealed that the LC molecules on the ion-beam irradiated LZO film were aligned homogeneously. Atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) were conducted to reveal the relationship between the ion-beam irradiation and the LC alignment. The ion-beam irradiation changed the LZO film surface to rougher than before by etching effect. Numerical roughness values from AFM analysis supported this phenomenon specifically. XPS analysis showed the chemical composition change due to the ion-beam irradiation by investigation of O 1s, La 3d and Zn 2p spectra. The ion-beam irradiation induced the breakage of chemical bonds in the LZO film surface and this occurred surface chemical anisotropic characteristics for uniform LC alignment.

I investigated the homogeneous liquid crystal alignment using parallel patterning on nickel oxide thin film. Nickel oxide thin film was prepared by sol-gel process, which is and cost effective method to form oxide thin film. Since the sol-gel process is solution driven method, the patterning on nickel oxide can be achieved by imprinting lithography. Nickel oxide with parallel pattern was used for liquid crystal alignment layer, which can be a alternative to conventional rubbing process to aligning a liquid crystal molecules. As a result, a high transmittance of 83.9% was confirmed for the NiO film, and a stable horizontal orientation pretilt angle of 0.2° occurred in the imprinted NiO film. These results were judged to be a positive level that can be commercialized in the horizontal alignment type liquid crystal display that is currently used universally. Anisotropic characteristics of nickel oxide induced by a parallel pattern leads to the alignment of liquid crystals.

The ion-beam irradiated lanthanum zinc oxide (LZO) films were conducted as liquid crystal (LC) alignment layer to achieve uniform and homogeneous alignment of LC molecules. Polarized optical microscopy and the pre-tilt angle measurements revealed the alignment characteristics of LC molecules on the LZO film surface. Physical characteristics of the LZO film surface were analyzed by field emission scanning electron microscope and atomic force microscopy. The strong ion-beam irradiation on the LZO film changed surface rougher than before and induced physical anisotropic characteristics. Chemical composition of the LZO film was investigated by X-ray photoelectron spectroscopy and it was revealed that the ion-beam irradiation induced the breakage of the metal-oxide bonds. Due to this, anisotropic dipole moment which related with van der Waals force between LC molecules and alignment layer was induced. Because of this, LC molecules were anchored to the LZO film surface to achieve uniform LC alignment. Collecting the capacitance-voltage curve, residual DC of the LC cell with the LZO films was measured and it was verified that the LC cell with the LZO film had a nearly zero residual DC. Therefore, the ion-beam irradiated LZO film is an efficient method as an LC alignment layer

Abstract We demonstrate convenient alignment technologies using imprinting lithography with sol-gel process. The aligned nano pattern is fabricated on a silicon wafer by laser interference lithography. For conformal imprinting process, aligned nano pattern was transferred onto the polydimethylsiloxane (PDMS). Using a PDMS sheet with aligned nano pattern, aligned nano pattern was created onto the sol-gel driven hafnium zinc oxide by imprinting lithography. The process was conducted at annealing temperatures of 150 °C. The obtained pattern on the HfZnO film acted as a guide for aligning liquid crystal (LC) molecules. The geometric restriction induced by aligned pattern leads to LC alignment along to the aligned nano pattern. The combination of imprint lithography and solution-processed inorganic materials proved good alternative of LC alignment technique.

In this study, we studied the alignment characteristics of liquid crystal on polyimide substrate when irradiated with ion beam in oblique direction on uniformly coated polyimide substrate. The inclined irradiation angle of the ion beam was set to 30 degree, 45 degree and 60 degree and the characteristics were observed for 1 minute and 2 minutes at an ion beam irradiation intensity of 600 to 3,000 eV for each angle. The Alignment of the liquid crystals were observed using a polarized microscope after preparing antiparallel specimens. The pretilt angle of the liquid crystal using the crystal rotation method was measured, and the applicability to actual products was evaluated. Experimental results showed that uniformly aligned liquid crystals could be obtained in samples irradiated at 1 and 2 minutes with an ion beam intensity of 1200 eV or higher when irradiated with 30 degree and 45 degree tilted ion beams. And, at 60 tilted degree, It shows that uniformly aligned liquid crystals could be obtained in samples irradiated at 1 and 2 minutes with an ion beam intensity of 2400 eV or higher. The pretilt angle of the liquid crystal showed the best characteristics when irradiated with ion beam inclined at 45 degrees, and it was confirmed that the pretilt angle was 0.2 to 1.3 degrees, which is usable for horizontally oriented LCD.

Liquid crystals offer plenty of useful activities as improving the stability of emulsion, increasing moisturizing power, drug release, improving skin feeling and visual effect for cosmetics fields. In order to prepare stable semi-transparent gel emulsion, liquid crystal emulsification method was used. The emulsion stabilities of systems containing glycerin, fatty alcohols, surfactants, water and oil were investigated at various temperatures as time passed. The stabilities of all emulsions were evaluated by means of a polarizing microscope, SEM, rheometer, colorimeter and DSC. Even though the samples stored at 50℃ thermostatic chamber were occurred the reduction of hardness, turbidity and △H and the peak shift, the semi-transparent gel emulsion was very stable without separation between water and oils phase in emulsion

In this study, the ion beam irradiation method on organic (polyamic acid and epoxy resin compound) overcoat layer was investigated. The use of ion beam on overcoat organic layer has the potential to replace conventional rubbing process. The traditional alignment layer is made by coating process and 2 times heat treatment on polyamic acid liquid. It requires many times and process steps. However, it is very economic and convenient process substitute polyimide alignment layer for organic overcoat. In order to characterize the LC alignment the polarized microscope image and pretilt angle measurement were investigated. The good LC aligning capabilities treated on the organic overcoat thin film surfaces with ion beam exposure of 45° at above ion beam energy density of 1200 eV were achieved.

Homogeneous liquid crystal (LC) alignment on hafnium strontium oxide (HfSrO) films prepared by sol-gel process via ion-beam (IB) bombardment was investigated. Uniform LC alignment was achieved on the IB-irradiated HfSrO films at IB intensity of 1.8 keV. We confirmed the effect of surface morphology on LC alignment using field-emission scanning electron microscope (FE-SEM). In addition, we observed electro-optical characteristics of the twisted-nematic (TN)-LC cells based on HfSrO films to verify the possibility of LC display (LCD) application.

이 연구는 슈크로오스디스테아레이트(Sucro-DS)를 사용하여 친수형 O/W 에멀젼을 만들고, 이 에멀젼의 드로플렛(droplet)은 다중층의 구조를 가지는 액정생성에 관한 것이다. Sucro-DS 의 물리화 학적 특성을 알아보았고, 이를 이용한 유화성능에 대하여 연구하였다. 액정을 형성하기 위하여 3wt%의 Sucro-DS, 5wt%의 글리세린, 5wt%의 수쿠알란, 5wt%의 카프릭/카프릴릭트리글리세라이드, 3wt%의 세토스테아릴알코올, 1wt%의 글리세릴모노스테아레이트, 78wt%의 정제수의 혼합계에서 안정한 다중층 의 라멜라구조가 형성됨을 알 수 있었다. 이를 응용하여 불안정한 활성물질을 봉입한 크림을 만드는 방 법에 대하여 기술하였다. 또한, 이 기술을 이용한 크림의 보습효과에 대하여 연구하였다. 인체 임상시험 을 통한 피부개선효과에 대하여 연구한 결과를 보고한다. Sucro-DS 를 사용하여 안정한 액정상을 생성 하는 pH 범위는 5.2~7.5 에서 안정한 액정구조를 유지하고 있었다. 액정의 안정성이 우수한 농도는 3wt%의 베헤닐알코올을 함유할 경우의 경도는 13kg/mm,min 이었다. 동일 함량의 점도는 25,000 mPas/min 이었다. 유화제의 영향에 대하여 실험한 결과, Sucro-DS 의 농도는 5wt%가 적합하였고, 안정 한 액정의 입경분포는 4~6mm 이었다. 이를 현미경분석을 통하여 관찰하였고, 3 개월동안 액정변화의 안 정성은 4℃, 25℃, 45℃에서 안정함을 알 수 있었다. 임상시험으로, 바르기 전의 보습력은 13.4±7% 이 었다. 액정이 형성되지 않은 크림의 보습력은 14.5±5%로 바르기 전보다는 약 8.2% 보습력이 상승하였 다. 반면, 액정크림의 경우 19.2±7%로, 도포 전보다는 43.3%보습력이 상승하였다. 응용분야로 Sucro-DS 유화제를 사용한 액정크림, 로션, 아이크림 등 다양한 제형개발이 가능하고, 화장품산업은 물 론 의약품산업 및 제약산업에서 피부외용제의 유화기술로 폭넓게 응용이 가능할 것으로 기대한다.

This review presents current progress in the preparation methods of liquid crystalline nanocarbon materials and the liquid crystalline spinning method for producing nano-carbon fibers. In particular, we focus on the fabrication of liquid crystalline carbon nanotubes by spinning from superacids, and the continuous production of macroscopic fiber from liquid crystalline graphene oxide.

In this study, skin permeation enhancement was confirmed by designing it to have a structure and composition similarity to the intercellular lipids that improve miscibility with skin by cross-linked lipids poloxamer. The cross-linked lipids poloxamer was synthesized and analyzed by 1H NMR that structure dose had conjugated pluronic with ceramide3. Active component is released by modification of liquid crystal structure because PPO part, large-scale molecule block of pluronic, has hydrophobic nature at skin temperature of 35℃. Conjugated pluronic with ceramide3 was synthesized using Pluronic F127 and p-NPC (4-nitrophenyl chloroformate) at room temperature yielded 89%. Pluronic(Ceramide 3-conjugated Pluronic) was synthesized by reaction of p-NP-Pluronic with Ceramide3 and DMAP. The yield was 51%. This cross-linked lipids poloxamer was blended and dissolved at isotropic state with skin surface lipids, phospholipid, ceramide, cholesterol and anhydrous additive solvent. Next step was preceded by α-Transition at low temperature for making the structure of Meso-Phase Lamella, and non-hydrous skin analogue liquid crystal using thermo-sensitivity smart sensor, lamellar liquid crystal structure through aging time. For confirmation of conjugation thermo-sensitivity smart sensor and non-hydrous skin analogue liquid crystal, structural observation and stability test were performed using XRD(Xray Diffraction), DSC(Differential Scanning Calorimetry), PM (Polarized Microscope) And C-SEM (Cryo-Scanning Electron Microscope). Thermo-sensitivity observation by Franz cell revealed that synthesized smart sensor shown skin permeation effect over 75% than normal liquid crystal. Furthermore, normal non-hydrous skin analogue liquid crystal that not applied smart sensor shown similar results below 35℃ of skin temperature, but its effects has increased more than 30% above 35℃.

Transparent liquid crystal gels with high oil content by fatty acid soap were investigated. The solubilization efficiency of the mineral oil was dependent on the process. The process of dropping water part into the solution of oil and surfactant was more efficient than the process of dropping water part into the surfactant solution and after that dropping oil. The fatty acid soap could not solubilize the high oil content, but under the certain range, addition of CDE (Coconut Diethanolamide), Arlacel 165 (Glyceryl Stearate/PEG-100 Stearate) and cetostearyl alcohol helped solubilize the high content oil. Also, the glycerin and water content had influence on the solubilization. Especially, higher oil content gel showed elastic feature.

The stocker system is another name of automated storage and retrieval system (AS/RS) and being popularly used as main material handling tools in Liquid Crystal Display (LCD) and semiconductor fabrication facilities. Recently the use of the stocker system

We present the structural, optical, and electrical properties of amorphous silicon suboxide (a-SiOx) films grown on indium tin oxide glass substrates with a radio frequency magnetron technique from a polycrystalline silicon oxide target using ambient Ar. For different substrate-target distances (d = 8 cm and 10 cm), the deposition temperature effects were systematically studied. For d = 8cm, oxygen content in a-SiOx decreased with dissociation of oxygen onto the silicon oxide matrix; temperature increased due to enlargement of kinetic energy. For d = 10 cm, however, the oxygen content had a minimum between 150˚ and 200˚. Using simple optical measurements, we can predict a preferred orientation of liquid crystal molecules on a-SiOx thin film. At higher oxygen content (x > 1.6), liquid crystal molecules on an inorganic liquid crystal alignment layer of a-SiOx showed homogeneous alignment; however, in the lower case (x< 1.6), liquid crystals showed homeotropic alignment.

수평 배향 액정 모드는 양의 유전율 이방성과 음의 유전융 이방성 액정을 사용한 프린지 필드 스위칭과 양의 유전율 이방성 액정을 사용한 인플래인 스위칭 모드가 대표적이다 . 이 대표적인 세 구동 방식의 화질 특성을 비교하기 위하여 각각의 최척화된 위상지연 값 조건하에서 밝기, 명암대비율과 색 특성을 조사하였다. 그 결과 양액정과 음액정을 사용한 프린지 필드 스위칭 모드가 밝기와 명암대비율 면에 있어서 인플래인 스위칭 모드보다 우수한 특성을 보인다. 또한 양액정을 사용한 프린지 필드 스위 칭 모드는 시야각 방향에서 적은 색 변이 특성을 보인다.

Thiol-ene 중합이 가능한 새로운 반응성 액정 단량체로서 2,5-bis[4'-(5-hexenyloxy) benzoyloxy]toluene를 합성하였다. 반응성 액정 단량체는 ethyl 4-hydroxybenzoate와 6-bromo-1-hexene을 반응하여 얻은 중간체인 4'-(5-hexenyloxy)benzoic acid와 methyl hydroquinone를 축합하여 79%의 수율로 합성하였다. 얻어진 반응성 액정 단량체의 구조는 1H-NMR과 FT-IR을 이용하여 확인하였으며, DSC와 온도 조절기가 부착된 편광현미경을 이용하여 관찰한 결과 65℃와 157℃ 사이에서 네마틱 액정상을 보임을 확인하였다. 반응성 액정 단량체는 1,6-hexanethiol, 광개시제와 함께 혼합하여 thiol-ene 중합을 위한 광중합 조성물을 제조하였다. 러빙 처리된 폴리이미드 기판 상에서 이와 같은 조성물을 코팅한 후 광조사에 의해 중합한 결과 λ/4의 위상차를 갖는 광학보상 필름을 제조할 수 있었다.