• Korean Journal of Materials Research
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• v.4 no.2
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• pp.194-205
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• 1994

In this research, we attempt to fabricate an excellent CFRC(Carbon Fiber Reinforced Carbon), which has good thermal and mechanical properties, with 8H/satin woven fabric prepreg, high modulus and high strength type continuous carbon fiber and raw coal tar pitch(RCTP) matrix or THF soluble fraction(THFSP) matrix which has good graphitizability. Green bodies were fabricated with hot press molding technique and CFRC samples were made after carbonization, impregnation, recarbonization and graphitization steps. For the purpose of characterization of the physical properties, SEM, polarized light microscope, TGA were observed, and tested flexural strength, modulus and ILSS. After heat treating the THFSP matrix up to $2300^{\circ}C$, the value of $C_0$/2 was 3.380$\AA$, which is analogous to the structure of natural graphite and the value of 2$\theta$ is $26.276^{\circ}$ approached to the Bragg's angle of natural graphite. As a result of TGA to test the high temperature air oxidation, the THFSP matrix, graphitized up to $2300^{\circ}C$, exhibited the best air oxidation resistance. And mechanical properties were increased up to 65~70% as fiber volume fraction increased. Because of the good orientation graphitizability, the fracture surface of THFSP matrix CFRC is very good.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.4
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• pp.197-206
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• 2010

The purpose of this study is to dye hanji/cotton fabrics using persimmon juice and to investigate the change in the hand fabrics. Using the Kawabata Evaluation System, we have examined the changes in the physical properties, primary hand value and total hand value. The dynamic characteristics of hanji/cotton fabrics have been explored by tensile, shear, bending, compression, surface properties, thickness and weight. As a result, it can be seen that the linearity of load-extension and tensile resilience are increased with the increase of the concentration and dyeing times of persimmon juice and tensile energy is decreased in the same condition. These behaviors are shown in the compression properties. Although the mechanism of persimmon juice dyeing has been widely discussed, it means that the fabrics dyed with persimmon juice become stiffened and the elasticity is increased with the introduction of persimmon on the fabrics studied. Bending rigidity and hysteresis of the bending moment are increased with the increase of the concentration and dyeing times of persimmon juice. Also, Geometrical roughness, expressed in SMD is increased with increasing the concentration and dyeing times of persimmon juice, compared with as-received. It indicates that these results are due to the geometric structure of hanji yarn and the introduction of persimmon juice on the fabrics studied. The fullness and softness with the soft feeing are increased a little due to the tannin component of persimmon juice introduced on the fiber surface.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.3
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• pp.516-529
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• 2018

This study investigated the dyeing properties and bio-functions of cotton fabrics dyed with naturally fermented Ecklonia cava extract in order to compare it with a comparison of unfermented extract. Hot water-extracted Ecklonia cava was fermented naturally under the various conditions of a fermenting period (2-8 days) and amount of molasses (0.1-1.8% v/v); in addition, it was also tested for characterization by FT-IR, antioxidant activity, total polyphenol content, and anti-microbial activity. For dyed cotton fabrics, color strength (K/S), physical color properties, dyeing fastness, sun protective property, and anti-microbial activity were evaluated considering dyeing conditions. As a result, the fermented dye under fermentation condition of 0.1% v/v with molasses during 4 days was revealed as having a similar chemical structure to the unfermented one and showed a total polyphenol content with 32.88mg/g and better antioxidant activity than the unfermented one. As for dyed fabrics, the color strength value by K/S was the highest under the condition of 0.1% v/v of molasses during 4 days among all fermenting conditions. The dyed fabrics had a reasonably good fastness (except for light). Anti-microbial activity against K. pneumoniae was better for the fermented extract-dyed fabric especially with lower dye concentrations.

• Fashion & Textile Research Journal
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• v.7 no.4
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• pp.439-444
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• 2005

This article describes the change in the hand value of chitosan-crosslinked cotton fabrics. The chitosan-crosslinked cotton fabrics were manufactured by mercerizing process using epichlorohydrin(ECH), 2% aqueous acetic acid and 20% aqueous sodium hydroxide. It proposed that the crosslinking and mercerizing were performed with the mixture of four different molecular weight chitosan and ECH in a single step. Cotton fabrics were dipped in the mixed solution of chitosan and ECH, picked up by mangle roller, pre-dried at $130^{\circ}C$, mercerized and crosslinked in NaOH solution and finally washed and dried. Mechanical and physical properties of the chitosan crosslinked fabric were measured on concentration and molecular weight by Kawabata Evaluation System(KES) and other instruments. As the concentration of chitosan solution increased, LT, WT, B, 2HB were increased. WT, B, 2HB, MIU, SMD, $T_0$, $T_m$ were decreased when chitosan was depolymerized. On the other hand, RT was increased when chitosan was depolymerized.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.9
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• pp.1593-1602
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• 2001

본 연구는 스포츠 아우터웨어용 나일론 직물의 소리에 대한 주관적 감각과 이에 관련된 객관적 측정치를 규명하기 위하여, 서로 다른 8종의 나일론 직물의 소리의 스펙트럼 파형을 고찰하였으며, 소리 파라미터로 총음압(level pressure of total sound, LPT),세 가지 AR (autoregressive)계수, Zwicker의 심리음향학적 모델에 따른 크기(Z)와 날카로움(Z)를 계산하였고, Kawabata Evaluation System(KES)으로 직물의 물리적 성질을 측정하였다. 주관적 감각 평가를 위하여 피험자에게 녹음된 각 직물소리를 들려주어 7개 소리 감각 (부드러움, 시끄러움, 날카로움, 맑음, 거 침, 높음, 유쾌함)을 의미분별척도로 답하게 한 후, 단계적 선형 회귀식을 이용하여 직물 소리의 주관적 감각에 대한 예측 모델을 제시하였다. 울트라스웨이드를 제외한 태피터 나일론 직물들은 스펙트럼 파형 에서 다른 조성 섬유의 직물들보다 음압 값이 높고, 총음압이 60dB 안팎의 값을 보여, 착용자에게 불쾌감을 줄 것으로 예상되었으며, 주관적 감각 평가에서도 소리의 부드러움과 맑음, 유쾌함에서 음의 점수를, 시끄러움과 날카로움, 거침, 높음에서 양의 점수를 얻었다. 주관적 감각의 예측모델에서 총음압은 시끄러움과 거침에 정적 영향을, 유쾌함에 부적 영향을 미쳐서 나일론 직물 소리의 총음압이 50dB 이하일 때 주관적으로 유쾌하게 느껴지는 것으로 나타났다.

• Textile Coloration and Finishing
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• v.27 no.1
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• pp.35-49
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• 2015

This paper investigated optimum process conditions of coating yarn for awning fabric. For this purpose, the simulation for processability and yarn quality using SPSS statistics package was carried out, and PP/TPO and PET/PVC coating yarns specimens were made with variation of extruder temperature and feed speed of core yarn on the yarn coating machine for examining simulation result. It was revealed that optimum coating conditions of PP/TPO 1000d coating yarn were extruder temperature $150^{\circ}C$, and core yarn feed speed 400~500m/min. Mechanical property and thermal shrinkage of PP/TPO coating yarn made at this conditions were best and core evenness rates of these coating yarns by yarn compression tester were also superior, which was certified by SEM photograph. In addition, these experimental results were coincided with simulation results. It was found that, in PET/PVC coating yarn, yarn physical properties between 1500d and 1200d coated yarns were not shown any difference, and core evenness rates of these coating yarns were superior. It revealed and concluded that these simulated coating conditions are applicable to production field.

• Textile Coloration and Finishing
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• v.19 no.1 s.92
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• pp.24-30
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• 2007

Heat storage/release system in textile is a useful tool to increase energy efficiency and enhance comfortable microclimate of clothing. Phase change materials(PCM) are used in regulating storage and release properties of thermal energy. To investigate the temperature regulating ability of fabrics with PCM microcapsule(PCMMc), Nylon fabrics were coated with PCMMc via wet processing and they were characterized by SEM, DSC and infrared thermal analyzer. Also, water moisture transpiration, water penetration resistance, peel strength and washing durability of the fabrics were assessed. The water vapor permeation and water penetration resistance decreased with increasing PCMMc content. In DSC analysis, it can be seen that the microencapsulated fabric showed both exothermic md endothermic phenomena at specific temperature. Peel strength was decreased with increasing PCMMc content.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.4
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• pp.609-619
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• 1996

Polyethylene Terephthalate (PET) has been used as a mainstream fiber to make silklike fiber. The silky characteristics such as softness, dry touch feeling and flexibility can be obtained by weight reduction treatment. In aqueous alkali solution, the surface of PET is dissolved away and reduced in weight. The PET fiber, yarn and fabric become thinner and the gaps between fibers are wider. Its mobility is greatly improved without change of basic structures of the treated PET fibrics. The alkali treatment was conducted under the various experimental conditions such as alkali (NaOH) concentration, treatment time and temperature. As the weight loss increased, drapability improved and tensile strength remarkably reduced. When the PET fabrics lost 30% in their weight, drape coefficient lowered as much as 30oA and tensile stregth lowered as much as 50%. The weight loss over 30% brings great improvement in drapability and dyeability and significant decline in durability. By the alkali treatment, absorbency in spectrophotometer of dyed PET can be increased as much as 82% due to the increase of the surface area and formation of microvoids on the surface.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.2 s.150
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• pp.338-347
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• 2006

Due to the complex environment in the ground, most of excavated costumes undergo deterioration and color change. To reduce the extent and intensity of the staining and to recover the original color or gray fabrics of excavated costumes, bleaching would be required. Excavated historical costumes are very delicate in nature, therefore, special care is needed in bleaching process. Several bleaching agents were selected and applied to the control cotton fabric and pre-deteriorated cotton fabrics to examine the change of color and physical properties after bleaching. A dual bleaching using hydrogen peroxide and sodiumborohydride showed the superior bleaching effect to the other bleaching agents. The strength of pre-deteriorated fabrics slightly increased after dual bleaching. The six historical costumes which belonged to General Duk-Ryung Kim's nephew's wife were dual bleached. They became remarkably cleaned and brightened. The treatments improved the appearance of costumes. By microscopic investigation, it is found that costumes did not show the damage after treatment. In conclusion, it is possible to bleach historical textiles without damage using appropriate bleaching agents like hydrogen peroxide and sodiumborohydride.

• Fashion & Textile Research Journal
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• v.6 no.5
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• pp.660-666
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• 2004

This article describes the change of hand value of chitosan crosslinked cotton fabrics. The chitosan crosslinked cotton fabrics were manufactured by mercerizing process using epichlorohydrin(ECH) as crosslinkins agent, 2% aqueous acetic acid as a solvent of chitosan and ECH, and 20% aqueous sodium hydroxide as a mercerizing agent and crosslinking catalyst. Cotton fabrics were dipped in the mixed solution of chitosan and ECH, picked up by mangle, mercerized and crosslinked in NaOH solution, and finally wash and dry. Mechanical and physical properties of the chitosan crosslinked fabric were investigated using Kawabata Evaluation System(KES) and other instruments. Tensile energy and tensile strain were decreased with the increase of the concentration of chitosan. Tensile resilience, compression resilience bending rigidity, bending hysteresis, shear stiffness, shear hysteresis, coefficient of friction, geometrical roughness, compression linearity, compressional energy, and thickness were increased with the increase of the concentration of chitosan. On the other hand, bending rigidity, bending hysteresis, coefficient of friction, geometrical roughness, compressional resilience, and thickness were increased with the increase of the concentration of crosslinking agent(epichlorohydrin).