• Carbon letters
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• v.5 no.1
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• pp.1-5
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• 2004

The effects of fiber surface-treatment and sizing on the dynamic mechanical properties of unidirectional and 2-directional carbon fiber/nylon 6 composites by means of dynamic mechanical analysis have been investigated in the present study. The interlaminar shear strengths of 2-directional carbon/nylon 6 composites sized with various thermosetting and thermoplastic resins are also measured using a short-beam shear test method. The result suggests that different surface-treatment levels onto carbon fibers may influence the storage modulus and tan ${\delta}$ behavior of carbon/nylon 6 composites, reflecting somewhat change of the stiffness and the interfacial adhesion of the composites. Dynamic mechanical analysis and short-beam shear test results indicate that appropriate use of a sizing material upon carbon fiber composite processing may contribute to enhancing the interfacial and/or interlaminar properties of woven carbon fabric/nylon 6 composites, depending on their resin characteristics and processing temperature.

• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.65-73
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• 1986

These studies are carried out to improve silk availability for anticrease by useing methacrylate monomer polymerization method with in silk fiber. For this purpose, degree of anticrease, stiffness and shrinkage of various silk fabrics, included finish or not, after repeat of washings and polyster fabric was compared as standard. The adopted samples are ; 1. Polyester, Georgette, Woven density…90cm-85g/m 2. Silk, Twill, Degumed, Light, Woven density…90cm-90g/m 3. Silk, Twill, Degumed, Heavy, Woven density…90cm-200g/m 4. Silk, Stain, Degumed, Light, Woven density…90cm-90g/m The reached results are as followings. 1. The results of improving on anticrease by the finished method were about ten per cent increase against their original samples. 2. The light density silks showed satisfactory improve for anticrease, but the heavy one remained as rather poor condition. 3. The results for degree of textile stiffness were investigated to make sure reserve their textile feeling and observed to be good condition upon the finish work. 4. Textile shrinkage after the repeat of soap wash was investigated on indivisual test sample and silk fabrics showed more shrinkage than polyester which it seemed to be tentering shrinkage druning their general finishing processes. 5. The investigation showed that anticrease, stiffness and shrinkage of the sample textile were more or less deteriorated regardless silk or polyester by the repeat of washings. These matters are considered that such results were obtained because of the fiber fatigue nature. 6. The report reached that silk textiles should be used by dry cleaning methed after finish of any resin finish to reserve their improved anticrease nature.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.1 s.26
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• pp.81-91
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• 1988

The purpose of this study is to investigate the physiolosical responses and subjective wear sensation to the clothes with different cellulose composition. The experimental garments were four types of cellulosic fabrics, respectively composed of $100\%$-cotton, $100\%$-Rayon, cotton/Flax 85/15, and rayon/Flax 85/15 (weft blended), were sewn in blouses with half-length sleeves. Four healthy women were chosen for this experiment. The condition of the experimental room were in two environments: Temp., $25{\pm}1^{\circ}C$, R.H. $60{\pm}3\%$ and Temp., $30{\pm}1^{\circ}C$, R.H. $70{\pm}3\%$, and air velocity was maintained at 0.25 m/sec. The results are as follows. 1) At $25^{\circ}C$, rayon blouse showed the pleasantest feeling because of its excellent humidity sensation and tactile sensation. At $30^{\circ}C$, rayon and flax blended blouse showed most comportable sensation. In both environments, blouse of $100\%$ cotton showed the least pleasant because of high vapor pressure inside the blouse and bad tactile sensation. 2) Vapor pressure inside the blouse and tactile sensation play the most impotant role in comfort. Consequantly the blouse made of $100\%$-cotton which bring low air permeability, moisture regain and water vapor permearbility showed more unpleastness than rayon blouse because it raises temperature, relative humidity and vapor pressure inside the blouse under the hot circumstances In the conditions with much sweat, rayon and flax blended blouse with high stiffness increases comfort better than $100\%$ rayon because the former prevents sticking to the skin.

• Composites Research
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• v.18 no.6
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• pp.19-25
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• 2005

This paper has performed an experimental study on the hybrid composite carbody of Korean tilting railway vehicle. The hybrid composite carbody has the length of 23m and is comprised of a 40mm-thick aluminium honeycomb core and 2mm-thick woven fabric carbon/epoxy face sheet. In order to evaluate the structural behavior and safety of the hybrid composite carbody, the static load tests such as vertical load, end compressive load, torsional load and 3-point support load tests have been conducted. The test was performed under Japanese Industrial Standard (JIS) 17105 standard. from the tests, the maximum deflection was 12.3mm and the equivalent bending stiffness of the carbody was $0.81\times10^{14}\;kgf{\cdot}mm^2$. The maximum strain of the composite body was below $20\%$ of failure strain of the carbon/epoxy face sheet.

• Fashion & Textile Research Journal
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• v.2 no.2
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• pp.150-158
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• 2000

This study investigated mechanical properties, drape coefficients and node indices of stretch fabrics. We applied mechanical properties to exhibited tailorability control in HESC and evaluated making-up. The mechanical properties such as tensile, bending, shearing, compression, surface characteristic values, thickness and weight were measured by the KES-F system and drape coefficient by drape tester. The summarized results of this study were as follows; First, stretch fabrics, almost, shown high stretch in weft inserted polyurethane yarn fabric and had a ${\pm}2{\sigma}$(sigma) range of shearing, compression, surface and thickness, except bending and weight, as compared with Japanese women's thin dress fabrics. Second, bending had a positive correlation in stiffness, anti-drape and flexibility & softness. Shearing had a negative correlation in crispness and scroop. Surface properties had a high contribution in fullness & softness. Third, The drape coefficient was found by measuring the mechanical properties according to the obtained regression equation. Forth, many problems are expected in overfeed and cutting operations in sewing process. In the decision of the good external appearance using TVA, only 26 of 55 samples are included in the range of the good external appearance. Fifth, in the regard of the result for sewing control, warp values are not necessary to control in the all kind of items. But weft value in the RT and EM are out of non-control zone. So we need a special management during sewing process.

• Korean Journal of Human Ecology
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• v.13 no.6
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• pp.997-1005
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• 2004

The purpose of this research is to measure the sensibility and preference of American consumers for domestically-manufactured cotton fabrics through 7-points scale questionnaires and the 4-dimensions and 8-axes system. The key words included such images as masculine-feminine, new-old, casual-classic, and ambiguous-orderly. The images of cotton fabrics were classified through a cluster analysis. This research also included an investigation of relationship between sensibilities for cotton fabrics and their physical characteristics. The sensibilities of cotton fabrics were classified into 4 groups: 'feminine sensibility,' 'masculine sensibility,' 'new sensibility,' and 'casual sensibility.' This result represents that American consumers' sensibility is simpler than Koreans'. The order of preference was 'feminine sensibility', 'masculine sensibility', 'new sensibility', and 'casual sensibility.' The sensibilities of cotton fabrics were explained significantly by stiffness, weight, weft density, value, and chroma. Specifically, those were more influenced by color characteristics such as value, chroma, and hue than by physical characteristics. We should be able to tell a difference in the reaction of a trading country's consumers and domestic consumers to domestically-manufactured cotton fabrics through comparing this research with the previous work(Shin & Lee, 2002). Additionally, we will be able to establish a basic strategy for successfully advancing Korean fabrics into the American domestic textile industry. In this way we can expect to increase the competitive power of our domestic clothes brands.

• Fashion & Textile Research Journal
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• v.10 no.4
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• pp.566-571
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• 2008

Frictional sounds of 8 vapor permeable water repellent fabrics by sound generator were recorded and analyzed through FFT fast Fourier transform analysis. The frictional Sounds were quantified by calculating level pressure of total sound(LPT), the level range(${\Delta}L$) and the frequency difference(${\Delta}f$). Mechanical properties were measured by KES-FB. LPT values of specimens finished wet coating were higher than those of other kinds of finishing. ${\Delta}L$ values of specimens laminated were highest. Absolute values of ${\Delta}f$ were high in the cire finished and laminated specimens. Values for bending rigidity, shear stiffness and energy required for the compression of coated specimens increased compared with the cire finished and laminated specimens. Laminated specimens had high values of frictional coefficient and low values of surface roughness. Relationship between frictional sounds and mechanical properties analysed by use of correlation coefficients and stepwise regression. LPT showed significant correlation with elongation, tensile energy, geometrical roughness, weight and thickness. ${\Delta}L$ was highly correlated with tensile linearity, frictional coefficient, and ${\Delta}f$ with tensile linearity, weight and thickness. LPT were revealed to be explained by elongation and weight. ${\Delta}L$were predicted by tensile linearity, and ${\Delta}f$ by tensile linearity and thickness.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.196-201
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• 2003

When the structures are used in cold regions, the mechanical properties and dimension stability of the blade will be changed. The proposal of this study is to test the durability of the structures in cold regions. It is necessary to select the most comfortable materials and fabrication processes for more stable structures in cold regions. To select the most comfortable materials and processes, the static strength has to know through the tensile static tests at the severe condition as cold regions. First, the tensile static specimens made by RIM (Resin injection molding) process & vacuum bagging process with reinforcement materials and resin. Tensile static tests were carried out on three laminate lay-ups (carbon prepreg, carbon fiber dry fabric) at different test temperature($24^{\circ}C$, $-30^{\circ}C$), determining properties such as the mechanical strength, stiffness and strain to failure. At different test temperature, in order to test the tensile strengths of these specimens used the low temperature chamber. Next, the results of this test were compared with each other. Finally, the most comfortable materials and fabrication processes can select based on these results. The results show the changes in the static behavior of three laminate lay-ups at different test temperatures. At low temperatures, the static strengths are higher than the ones at room temperature.

• Composites Research
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• v.23 no.1
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• pp.44-50
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• 2010

In this paper, two different experiments, namely, salt water spray and salt water immersion, were performed to reproduce the contact of composites with the seawater for three kinds of woven fabric composite material systems which would be used for the WIG(wing in ground effect)craft. After aging 140 days in the salt water environment, material properties of carbon/epoxy and glass/epoxy composite such as tensile, compressive and shear stiffness and strength, and inter-laminar shear strength (ILSS) were measured. By comparing baseline material properties with degraded ones, the effects of the salt water environment on the composite mechanical properties were evaluated. From the experiments, it was confirmed that the difference in aging conditions had very small influence on composite properties. And it was found that tensile strength of carbon/epoxy composites showed little degradation, but much more degradation was observed in glass/epoxy composites. And large degradations on matrix dominant properties were observed. The salt water could damage the fiber-matrix interface, matrix properties and the glass fiber.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.5
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• pp.754-764
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• 2010

Most silk fabrics are produced only after the degumming process to make the best use of the properties and have restricted silk processing that do not hinder their performance. However, considering the highly increased preference for natural fibers and the shortage of raw silk, high-quality upgraded silk product functions are required by the development of a processing technology and a good design. This study analyzes the changes with the samples by the functional finish such as softening finishing, wash and wear, tannin weighting by measuring the objective hand of scoured silk and three finished ones using KES-FB. As a result, the change of objective hand of finished silk fabrics that improves functionality was analyzed and compared. The increase of KOSHI after the finish became stiffer show that the silk fabric samples are appropriate for summertime clothes with the retention of a certain clothing climate for the body. The stiffness of finished fabrics for the normal had a closer relationship with the density of fabrics than the type of finishing. The samples (after the softening finishes) maintain better elasticity according to the properties of the softener and the finishing agent. Although the specimens of this study were thin fabrics, their elasticity against compression increased after the softening finishes and became softer than degummed silk. The surface properties of georgette were changed by all types of finishing.