• 한국의류산업학회지
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• 제17권6호
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• pp.1020-1029
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• 2015

This paper investigated the wearing performance of knitted fabrics made of air vortex yarns using PTT/tencel/cotton fibres in comparison with ring and compact yarns for emotional garment. Wicking property of knitted fabric made of MVS yarns was worse than those by ring and compact yarns, however, drying property of knitted fabric made of MVS yarns was better than those by ring and compact yarns, which was explained as more water vapor transport due to larger openness between fibres in the MVS yarns than those in the ring and compact yarns. Thermal conductivity of knitted fabric made of MVS was lower than those of ring and compact yarns and maximum heat flow(Q_max) at the transient state of MVS knitted fabric was lower than those of ring and compact yarns, which may be attributed to MVS yarn structure that has parallel fibres in the core part of the yarn and fasciated fibre bundles on the sheath part with roughness on the yarn surface. However, pilling of MVS knitted fabric was better than those by ring and compact yarns, which was caused by less and shorter hairy fibres protruded from MVS yarn surface than those of ring and compact yarns. It was observed that tactile hand of MVS yarn knitted fabrics was stiffer than those of ring and compact yarns knitted fabrics. It was explained by low extensibility and compressibility and high bending and shear rigidities of the MVS yarn knitted fabrics, which resulted in bad wearing performance of MVS knitted fabric.

• 폴리머
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• 제24권3호
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• pp.326-332
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• 2000

유리섬유/불포화 폴리에스터 복합재료에서 섬유에 처리된 사이징제가 복합재료의 최종 물성에 미치는 영향을 상온에서의 접촉각 측정을 통해 고찰하였다. 본 연구에서는 폴리비닐알코올, 폴리에스터, 그리고 에폭시계 사이징제를 사용하여 유리섬유의 표면을 처리하였으며 각각의 물성을 비교하였다. 유리섬유의 접촉각은 증류수와 diiodomethane을 젖음액으로 사용하여 Washburn식을 기본으로 한 wicking법으로 측정하였다. 결과적으로 접촉각 측정에 의해 구한 표면자유에너지는 에폭시계 사이징제로 치리된 유리섬유에서 최대값을 나타내었다. 복합재료의 층간 전단 강도 (ILSS)와 파괴 인성 ( $K_{IC}$ )의 측정 결과로부터 사이징제의 처리에 따라 계면 결합력이 증진되며 결과적으로 복합재료의 기계적 강도가 증가함을 알 수 있었다. 이것은 복합재료에서 유리섬유의 표면 자유에너지 증가에 기인한다고 사료된다.

• Composites Research
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• 제31권6호
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• pp.379-384
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• 2018

본 연구에서는 동일한 표면 형태를 가지는 탄소섬유에 다양한 사이징제를 처리함에 따라 발생하는 에폭 시 수지의 유동 특성 변화를 분석하였다. 동적 접촉각(DCA) 측정을 통해 단일 탄소섬유의 젖음성(Wettability)을 측정하였다. DCA 측정 결과와 함침 특성 간의 연관성을 살피기 위해 Wicking test와 VARTM test를 수행하였다. 추가적으로, 탄소섬유의 표면 에너지 등 다양한 표면 특성을 분석하였으며 Micro-droplet test를 통해 수지와 탄소섬유계면의 계면전단강도를 측정하였다. 이러한 실험 결과를 기반으로, 함침 속도의 증대를 위해서는 탄소섬유의 사이징제가 적정 수준의 표면 에너지를 가져야 하며, 사이징제의 화학적 조성을 조정하여 에폭시 수지의 유동 특성과 계면전단강도가 모두 개선 가능함을 확인하였다.

• 한국세라믹학회지
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• 제31권8호
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• pp.823-828
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• 1994

Dispersion condition of Si3N4 powder in molten wax was established by comparing relative viscosity of mixture with 20 vol% solids loading, while the evaluation of compression-molded sample was demonstrated as an effective method for developing a binder system for injection molding. The best dispersion of Si3N4 powder in molten wax was achieved when Si3N4 powder was treated with 5% stearic acid, and the critical powder volume fraction was determined to be about 0.51 from density measurement of compression-molded samples. Samples containing polar secondary binder showed markedly improved green strength, higher thermal expansion and increased wicking rate in the early stage.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.113-113
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• 2003

Four main factors, cling force, wicking force, water retention and water transport, affecting the clinginess of the sportswear fabric have been identified and measured by combining a new equipment and a statistical analysis. A classification model based on those factors has been developed in order to evaluate and standardize fabric wear comforts during heavy physical acting. Ten sportswear fabrics assumed different in their wear characteristics have been employed to investigate the relationship between the measurements and actual performance. It has been shown that the subjective evaluation ratings were well agreed with the measurement.

• 한국염색가공학회지
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• 제17권1호
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• pp.14-19
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• 2005

Study on the use of enzymes for textile wet processing has been very active. The exploratory research conducted herein is related to the bioscouring process for cotton fabric. The optimum concentration of alkaline pectinase(BioPrep) was in the range of 0.05～0.2 g/l, the proper treatment time was 30～60 minutes, the appropriate treatment temperature was $60^{\circ}C$ for both the batch method and the padding method. The simultaneous desizing/bioscouring by padding method did not give water absorbency as good as the bioscouring after desizing. Color of fabrics which were bioscoured and dyed with direct dyes and a reactive dye was just a little darker than that of NaOH scoured one. K/S and Lab values of the bioscoured fabrics, regardless of the degree of water absorbency, were quite similar to each other.

• 한국염색가공학회지
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• 제18권5호
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• pp.61-71
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• 2006

This paper addresses the factors hindering the image quality of lines in inkjet printed on polyester fabric as printing media. Lines were printed onto different types of polyester fabrics in warp and filling directions. Line image quality including line width, edge blurriness, and edge raggedness was assessed. The effect of capillary wicking on line image quality of printed spun polyester fabric is discussed. The factors on the image quality include printing position(top of the yam or between the yarn), printing direction(warp or filling), yarn structures(filament or spun), thread size(yam or fiber), finishing, and ink properties(evaporation rate). More than 30% differences in image quality results were observed by changing the printing location on the spun polyester fabric. The best results of the image quality were obtained with the printed plain and spun polyester fabrics. The fiber sizes may affect capillary size; therefore, the image quality can be dissimilar. Types of finishing materials and inks greatly improve the line image quality on spun polyester fabrics.

• 한국의류학회지
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• 제25권1호
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• pp.61-70
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• 2001

As important factors determining human sensorial comfort, liquid moisture management and surface properties of heat resistant workwear materials were examined. To figure out liquid moisture management properties of the test materials, absorption capacity, rate of absorption, and evaporation properties were assessed. A modified GATS(Gravimetric Absorbency Testing System) was used to measure the liquid moisture accumulation associated with the wicking of liquid moisture from sweating skin. The GATS procedure measures demand wettability of materials to take up liquid in a direction perpendicular to the fabric surface and it was modified to incorporate a special test cell and cover to assess absorption behavior in the presence of evaporation. Fabric stiffness, smoothness, number and the length of surface fibers, and an estimate of the contact area between the skin and fabric surface were measured to characterize the mechanical and surface properties of the test materials. Also an estimate of the force with which a fabric clings to moist skin was made using as wet-cling index.

• 대한기계학회논문집B
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• 제31권11호
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• pp.949-956
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• 2007

Pool boiling critical heat flux (CHF) of nanofluids with oxide nanoparticles of $TiO_2$ or $Al_2O_3$ was experimentally investigated under atmospheric pressure. The results showed that a dispersion of oxide nanoparticles significantly enhances the CHF over that of pure water. Moreover it was found that nanoparticles were seriously deposited on the heater surface during pool boiling of nanofluids. CHF of pure water on a nanoparticle-deposited surface, which is produced during the boiling of nanofluids, was not less than that of nanofluids. The result reveals that the CHF enhancement of nanofluids is absolutely attributed to modification of the heater surface by the nanoparticle deposition. Then, the nanoparticle-deposited surface was characterized with parameters closely related to pool boiling CHF, such as surface roughness, contact angle, and capillary wicking. Finally, reason of the CHF enhancement of nanofluids is discussed based on the changes of the parameters.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.328-328
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• 2011

Wetting phenomena have been heavily studied for industrial and academic researches especially tuning the wettability between hydrophilicity and hydrophobicity. Wicking through the surface texture is shown on superhydrophilic surface while rolling (or dewetting) on the patterns of superhydrophobic surface. These wetting phenomena are known to be affected by surface wettability determined with physical surface patterns as well as chemical composition of surface layer. In this research, we introduce a method to control the wettability of a thin C-SiOx film from hydrophobic to hydrophilic using a mixture gas of HMDSO/$O_2$ by plasma polymerization with rf-CVD (radio frequency-Chemical Vapor Deposition). Wettability was finely controlled by changing the ratio of HMDSO/$O_2$. Hydrophilicity increased as the ratio decreased, while hydrophobicity was enhanced by the ratio. Moreover, fine control from superhydrophilicity to superhydrophobicity was achieved by C-SiOx coating on the Si wafer with prepatterns of submicron-sized pillar array formed by $CF_4$ plasma etching.