• Transactions on Electrical and Electronic Materials
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• 제3권4호
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• pp.36-40
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• 2002

The polar anchoring strength and surface ordering in a NLC,4-n-pentyl-4'-cyanobiphenyl (5CB), on a rubbed polyimide (PI) surface containing trifluoromethyl moiety were studied. The large extrapolation length de of 5CB for washing process of water was measured at RS=114 mm. The polar anchoring energy of 5CB on the rubbed PI surface is decreased by the washing process. Also, the polar anchoring energy of 5CB increases with the rubbing strength on the PI surface. The surface ordering of 5CB for all washing processes is smaller than the non-washing process; it is attributed to the washing process.

• 한국정밀공학회지
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• 제25권12호
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• pp.27-32
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• 2008

• 한국염색가공학회지
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• 제29권4호
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• pp.276-283
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• 2017

The aim of this study is to develop an effective dyeing process for black color on the silk fabrics, using natural Indigo, Madder, Amur cork tree, Alder, Logwood, and Gallnut. All natural dye materials were water-extracted, concentrated, and freeze-dried. Seven different processes were carried out and the color differences(${\Delta}E$) of black color with each process from the chemical black dyed fabric were compared. The light, washing, and rubbing fastness were evaluated. The black dyeing of the silk fabrics was well carried and excellent black color was obtained in every methods. The profound black color could be obtained by the subtractive mixture of the three primary colors of red, yellow, and blue in the order of indigo(blue) - amur cork tree(yellow) - madder or lac(red). Black color was efficiently obtained by iron mordant when logwood or alder fruit was used. The color difference(${\Delta}E$) from the black color with chemical dyestuff was the lowest in the indigo - amur cork tree - lac - iron method. Light fastness and washing fastness were excellent in all dyeing processes, showing grade 5. The fastness to rubbing was excellent as shown grade 5 in the dry samples of logwood - iron process and alder fruit - iron process.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 및 기술 세미나 논문집 디스플레이 광소자
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• pp.41-41
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• 2008

In general, polyimides (PIs) are used in alignment layers in liquid crystal displays (LCDs). The rubbing alignment technique has been widely used to align the LC molecules on the PI layer. Although this method is suitable for mass production of LCDs because of its simple process and high productivity, it has certain limitations. A rubbed PI surface includes debris left by the cloth, and the generation of electrostatic charges during the rubbing induces local defects, streaks, and a grating-like wavy surface due to nonuniform microgrooves that degrade the display resolution of computer displays and digital television. Additional washing and drying to remove the debris, and overwriting for multi-domain formation to improve the electro-optical characteristics such as the wide viewing angle, reduce the cost-effectiveness of the process. Therefore, an alternative to non-rubbing techniques without changing the LC alignment layer (i.e, PI) is proposed. The surface of LC alignment layers as a function of the ion beam (IE) energy was modified. Various pretilt angles were created on the IB-irradiated PI surfaces. After IB irradiation, the Ar ions did not change the morphology of the PI surface, indicating that the pretilt angle was not due to microgrooves. To verify the compositional behavior for the LC alignment, the chemical bonding states of the ill-irradiated PI surfaces were analyzed in detail by XPS. The chemical structure analysis showed that ability of LCs to align was due to the preferential orientation of the carbon network, which was caused by the breaking of C=O double bonds in the imide ring, parallel to the incident 18 direction. The potential of non-rubbing technology for fabricating display devices was further conformed by achieving the superior electro-optical characteristics, compared to rubbed PI.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.399-399
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• 2007

Recently, it is widely studied to liquid crystal (LC) alignment using ion-beam exposure. Because conventional rubbing method has some problems such as defects from dust and electrostatic charges during rubbing process. Therefore rubbing-free techniques like ion-beam method are strongly required. We studied LC alignment by controlling ion-beam energy density and electro-optical (EO) characteristics of twisted nematic LC on the polyimide surface. In this experiment, a good uniform alignment of the nematic liquid crystal (NLC) with the ion-beam exposure on the polyimide (PI) surface was observed. In addition, it can be achieved the good EO properties of the ion-beam-aligned twisted nematic liquid crystal display (TN-LCD) on PI surface.

• 한방안이비인후피부과학회지
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• 제24권2호
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• pp.28-34
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• 2011

Background & Objectives : Allergic rhinitis is an inflammation or irritation of the mucous membranes that line the nose. Common symptoms include sneezing, a stuffy or runny nose, itchy eyes, nose and throat, and watery eyes. We aimed to determine therapeutic effects of Tribulus terrestris by observing changes of total IgE level and the scratching or rubbing around the nose behavior. Materials and Methods : Fifteen BALB/c mice were divided into three groups : AR group(allergic rhinitis elicitated), TT group(which ate herbal medicine) and AH group(which ate antihistamine). Allergic rhinitis was induced in the three groups by intraperitoneal and intranasal sensitization with 0.1% ovalbumin solution. Then Tribulus terrestris was orally administered only to the TT group of 28days, while the AH group was given antihistamine. We observed changes of total IgE level and the scratching or rubbing around the nose behavior. We used Kruskal-Wallis test statistically(p<0.05). Results : 1. Tribulus terrestris showed significantly decreased IgE level on the serum of the rat model. 2. Tribulus terrestris showed significantly decreased scratching or rubbing around the nose behaviors of the rat model. Conclusion : According to the above results, it is considered that Tribulus terrestris has an inhibitory effect on the process of allergic rhinitis and it can be used in relieving symptoms of allergic rhinitis.

• 한국의류학회지
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• 제30권8호
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• pp.1169-1177
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• 2006

The aim of this study was to investigate the change of the weight loss, tensile strength, flex stiffness, and color-values of the pigment-dyed cotton, polyester/cotton, polyester and nylon fabrics after washing process. Pigment-dyed cotton and polyester/cotton fabrics were treated with the cellulase, of which concentrations were 0, 1, 3 and 5g/l. The time of washing process ranges from 30 to 120 minutes. Pigment-dyed polyester and nylon fabrics were treated without enzyme, of which the washing temperature were 13, 30, $55^{\circ}C$ and the washing time ranges from 30 to 120 minutes. Also, they were tested in terms of the influences of agitation speed(rpm) and additives such as softeners, enzymes, detergents. The weight loss and tensile strength of the pigment-dyed cotton and polyester/cotton fabrics were positively correlated with the concentration of cellulase and washing time. Neither polyester nor nylon fabrics exhibited any change of the weight. All fabrics showed the decline of flex stiffness and decoloration after washing process. Decoloration of cotton and polyester/cotton fabrics was due to both the influence of cellulase and the mechanical rubbing. On the other hand, that of polyester and nylon fabrics was caused by the mechanical rubbing only.

• 한국염색가공학회지
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• 제22권2호
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• pp.101-109
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• 2010

The objective of this study is to investigate the characteristics of natural indigo dyeing of cotton fabric. Reduction and dyeing were carried out by one-step process using an infrared dyeing machine at the liquor ratio of 1:100, and subsequently oxidation and washing in water were followed. Dye uptake was increased with the increase of indigo concentration. Over the full range of dyeing tests, the dyeing condition was optimized to $40^{\circ}C$ for 40min. For most of dye concentrations, the cotton fabrics showed mainly PB color. Maximum K/S value was shown at 4g/L of sodium hydrosulfite concentration and the color strength increased with the increase of dye concentration. Value(lightness) decreased with the increase of dye uptake irrespective of mercerization or reduction method, while the mercerized cotton showed two times higher dye uptake than the untreated cotton. Whereas hue of the untreated cotton showed large decrease of P character(5.6~3.5 PB) with the increase of dye uptake, that of the mercerized cotton increased P character(4.7~5.5 PB). Irrespective of mercerization, value and chroma decreased with the increased of dye uptake. In addition, the untreated showed lower chroma than the mercerized cotton. In the case of traditional reduction, hue of the untreated cotton was changed very little with the increase of dye uptake. For hydrosulfite reduction, P character decreased with the increase of dye uptake. The difference of hue value was small with the change of reduction method(hydrosulfite reduction or traditional fermentation). Color character was not influenced by the changed maximum absorption wavelength. Washing fastness showed 4~4/5 shade change rating without any staining. And dry rubbing fastness was good at low color strength. The bacterial reduction ratios of dyed cotton fabric were also increased.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.103-104
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• 2010

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.914-917
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• 2002

We have obtained high performance and low voltage driving OCB panel by reducing the critical voltage and retardation matching between liquid crystal layer and compensation films. The critical voltage in the panel has been minimized by flattening color filter layer and optimizing a rubbing process. In addition, an appropriate retardation of the film and LC layer has scanned to achieve low driving voltage and high transmission. The proto-type 17" WXGA OCB panel has demonstrated with less than 5V drive and over 80 degree for all viewing direction except for rubbing direction with over 90% of TN light efficiency.