• Korean Journal of Optics and Photonics
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• v.26 no.4
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• pp.195-202
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• 2015

We developed a reflection ellipsometer so that one can measure the extremely small optical anisotropy of a rubbed polyimide alignment layer, without being disturbed by the residual anisotropy of the substrate. The optical anisotropy of the alignment layer was measured as rubbing strength was increased, and the measured anisotropy was compared to the retardation obtained by using a transmission-type ellipsometer, to confirm the reliability of our reflection ellipsometer. With this measured anisotropy we could verify the formation of an alignment layer by rubbing, and could quantitatively evaluate the formation of the alignment layer.

• Journal of Fashion Business
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• v.21 no.2
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• pp.105-112
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• 2017

A string wallcovering is a kind of textile wallcovering which is made of cellulose fiber yarn laminated on base paper. Compared with normal paper or PVC wallpaper, a string wallcovering is preferred continually in the interior design market, as it is not only environmentally friendly but it also has less cost on mass production without the weaving process and has a natural visual effect, excellent functionality such as thermo keeping, permeability, sound absorption. However, in the dyeing process, it is not appropriate to use plenty of energy such as water, electricity, steam or chemicals considering the environmental trend and the government policy plenty of energy such as water, electricity, steam or chemicals. Currently, a string wallcovering is made of raw white yarn and padding with direct dye or pigment which includes toxic elements, especially the use of direct dye is restricted in a part of the developed country due to inclusion of azo. In this study, we researched dyeing based on cold pad batch dyeing of a string wallcovering with reactive dyestuff. The peel strength and bending depth test confirmed that the optimum adhesive type and spread amount improved the water resistance of the string wallcovering. Also, pad batch dyeing with optimum reactive dyestuff enhanced the color fastness to light and rubbing in dry and wet conditions. Additionally, for improvement of color fastness to rubbing in a wet condition, the additional treatment finishing without soaping process which is used water. The results of this study can be used as basic data for environmentally friendly and energy saving of the textile wallcovering.

• The Research Journal of the Costume Culture
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• v.21 no.6
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• pp.967-973
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• 2013

During high speed sewing, the needle thread is exposed to dynamic loading, short strike loading, inertia forces, friction, rubbing, force of check spring, bending, pressure, friction, impact, shock and thermal influence. The dynamic thread loading/tension alters throughout the stitch formation cycle and along its passage through the machine. The greatest tensile force occurs at the moment of stitch stretching, when the take up lever pulls for required thread length through the tension regulator. These stresses act on the thread repeatedly and the thread passes 50-80 times through the fabric, the needle eye and the bobbin case mechanism, before getting incorporated into the seam, which result in upto 40% loss in tensile strength of the sewing thread. This damage in the sewing thread adversely affects its processing and functional performance. In this paper, the contribution of dynamic loading, passage through needle and fabric, and bobbin thread interaction in the loss in tensile properties has been studied. It is observed that the loss in tensile properties occurs mainly due to the bobbin thread interaction. Dynamic loading due to the action of take up lever also causes substantial loss in tenacity and breaking elongation of cotton threads.

• Fashion & Textile Research Journal
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• v.20 no.5
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• pp.608-615
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• 2018

The purpose of this study is to investigate the dyeability and functional properties of dyed fabric with the extract of Myrica rubra rind. For this purpose, the ultraviolet and visible spectra of the bark extracts were investigated. The dyeing temperature, dyeing time, mordant type, mordanting order, mordant concentration and dyeability were investigated. The color fastness based on washing, dry-cleaning, rubbing and light were evaluated by the types of Myrica rubra rind extract used. In addition, the deodorization and antibacterial activity were measured, and the functionality of the silk fabric dyed with the extract of the Myrica rubra rind was evaluated. The result shows that the color strength of the dye was excellent when the Myrica rubra rind was dyed at $80^{\circ}C$ for 80 minutes. The mordant dye color strength was high in the order of Fe mordant> Cu mordant> Al mordant. The dyeability of Al and Cu mordant was high during pre-mordanting compared to Fe mordant, and the dyeability of Fe mordant was high during post-mordanting than Cu and Al mordant. The deodorant property of the dyed fabric stained with the Myrica rubra rind extract was 92.4% and that of antibacterial property was 99.9% for Staphylococcus aureus and Klebsiella pneumoniae bacteria respectively.

• Textile Coloration and Finishing
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• v.27 no.4
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• pp.318-326
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• 2015

A pre-treatment process is essential for getting high quality of digital textile printing(DTP). In this study, we have studied three kinds of carrageenan polymer(k-, ${\lambda}$-, i-Carrageenan) as a pre-treatment thickening agent for the first time. Alginate polymer was also examined and its results were compared with that of the three kinds of carrageenan polymer. To confirm the performance of each thickening agent, we examined for a sharpness, color strength and fastness(washing, rub, light). The result showed that ${\lambda}$-Carrageenan has superior property in sharpness with low viscosity and i-Carrageenan was excellent in the color strength among the pre-treatment agents. Washing fastness to color change and staining for the all samples were 4 or 4-5 grade. Both dry and wet rubbing fastness of the samples were 4-5 grade. However, ${\lambda}$-Carrageenan coated sample has the lowest grade in light fastness. As a result, we found the possibility of carrageenan polymer as pre-treatment agent.

• Journal of the Korean Home Economics Association
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• v.50 no.2
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• pp.85-92
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• 2012

This was a study examining the fatliquoring of natural dyed cow skin with Coptis chinensis Franch. The K/S according to optimal dyeing condition, mordants and mordanting method was measured. And the surface, sections, tensile strength, elongation, stiffness and colorfastness according to post-dyeing fatliquoring were observed. The optimal conditions include 300%(o.w.f.), $50^{\circ}C$, 30 minites. Fe-simmordanting showed the highest dyeability. Coptis chinensis Franch showed a yellow color regardless of mordants and mordanting methods. Tensile strength and elongation increased in the case of simmordanting compared with untreated and the process of fatliquoring further increased. The softness significantly increased when fatliquored. Shrinkage was slightly reduced when dyed, but showed almost no change with fatliquoring. Lastly, color fastness increased overall with mordanting and partly increased with fatliquoring. The rubbing and light fastness were excellent Cu- mordanting, and drycleaning fastness also improved with Cr-mordanting.

• Textile Coloration and Finishing
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• v.30 no.4
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• pp.237-244
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• 2018

Three super hydrophobic red fluorescence dyes were selected to dye high molecular weight polyethylene fiber. Their absorbance and emission spectra were obtained and Stokes' shift was measured. Fluorescence emission strength of the dyes on the fiber was investigated and therefore Fluoro Red 3 was determined as the best one among those three dyes in this experiment. Dyeing properties and fluorescence intensities were investigated using the Fluoro Red 3 on high molecular weight polyethylene fiber at various dyeing conditions. The optimum concentration of a dispersing agent was appeared at 10wt% in aqueous solution. The best dyeing was obtained at $125^{\circ}C$ for 1 hour. The color fastnesses to the washing and rubbing were as high as ratings 4~5, however, the fastness to light was exhibited ratings 2~3.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.34-36
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• 2008

The several monoazo red dyes having different alkyl substituents were synthesized to dye unmodified polypropylene fiber. The affinity of the dyes onto unmodified polypropylene was increased with the increase of the length of alkyl substituents. Therefore, the hexyl-substituted dye having the longest alkyl group in this experiment showed very high color strength of dyeings with K/S value of over 28 at maximum adsorption wavelength. The color fastnesses of washing, light, rubbing and sublimation were also improved significantly for the longer alkyl substituted dyes.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1442-1446
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• 2006

In this paper, the response surface modeling of the pretilt angle control in the nematic liquid crystal (NLC) on the homogeneous polyimide surface with different surface treatment is investigated The rubbing strength and the hard baking temperature are considered as input factors. After the design of experiments is performed, the process model is then explored using the response surface methodology. The analysis of variance is used to analyze the statistical significance and the effect plots are also investigated to examine the relationship between the process parameters and the response.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.133-135
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• 2003

The washing effects on pretilt angle generation in a nematic liquid crystal (NLC), 4-n-pentyl-4’-cyanobiphenyl (5CB) on a rubbed polyimide (PI) surface with trifluoromethyl moiety have been successfully studied. The pretilt angle of 5CB is increased by the washing process on the rubbed PI surface. The surface tension on the rubbed PI surface increases with the rubbing strength RS and then saturated above RS=150 mm. The pretilt angle of 5CB for all washing processes on the rubbed PI surface decreases with the surface tension. We have found that the pretilt angle of 5CB on the rubbed PI surface may be attributed van der walls (VDW) dispersion interaction between the LC molecules and the polymer surfaces having trifluoromethyl moieties.