• Advanced Composite Materials
• /
• v.16 no.4
• /
• pp.335-347
• /
• 2007

Green composites composed of long maize fibers and poly $\varepsilon$-caprolactone (PCL) biodegradable polyester matrix were manufactured by the thermo-mechanical processing termed as 'Sequential Molding and Forming Process' that was developed previously by the authors' research group. A variety of processing parameters such as fiber area fraction, molding temperature and forming pressure were systematically controlled and their influence on the tensile properties was investigated. It was revealed that both tensile strength and elastic modulus of the composites increase steadily depending on the increase in fiber area fraction, suggesting a general conformity to the rule of mixtures (ROM), particularly up to 55% fiber area fraction. The improvement in tensile properties was found to be closely related to the good interfacial adhesion between the fiber and polymer matrix, and was observed to be more pronounced under the optimum processing condition of $130^{\circ}C$ molding temperature and 10 MPa forming pressure. However, processing out of the optimum condition results in a deterioration in properties, mostly fiber and/or matrix degradation together with their interfacial defect as a consequence of the thermal or mechanical damages. On the basis of microstructural observation, the cause of strength degradation and its countermeasure to provide a feasible composite design are discussed in relation to the optimized process conditions.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.23 no.1
• /
• pp.140-146
• /
• 1999

Colorants in green tea were extracted freeze-dried and analyzed to investigate the possibility of using as a natural dye. Fractionation of the colorants was carried out by column chromatograpy. Colorants in green tea were eluted into five fractions. All the fractions except fraction F2 showed absorption peakat 280nm. Fraction f2 showed absorption peak at 270nm and broad peak at 350nm, From the IR analysis it is speculated that fractions F2-F5 having similar stucture but different molecular weight are catechis. Silk fabrics dyes with fractions F1-F4 showed yellowish red color while sample dyed with fraction F5 showed red color. The colorants from green tea infusion was applied to silk wool nylon cotton and rayon fabrices. It showed relatively good affinity to protein and polyamide fibers bur low affinity to cellulose and regenerated cellulose fibers.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2007.11a
• /
• pp.93-102
• /
• 2007

Biocomposite was organized with biodegradable polymer and natural fiber that has potential to be used as replacement for glass fiber reinforced polymer composite with the benefits of low cost, low density, acceptable specific strength, biodegradability, etc. Until now, non-wood fibers have been used as reinforcements of biocomposite which are all plant-based fibers. The present study focused on investigating the fabrication and characterization of biocomposite reinforced with red algae fiber. The bleached red algae fiber(BRAF) showed very similar crystallinity to the cellulose. It has high stability against thermal degradation (maximum thermal decomposition temperature of 359.3$^{\circ}C$) and thermal expansion. Biocomposites reinforced with BRAF have been fabricated by a compression molding method and their mechanical and thermal properties have been studied. The storage modulus and the thermomechanical stability of PBS matrix are markedly improved with reinforcing the BRAF. These results support that the red algae fiber can be used as an excellent reinforcement of biocomposites as "green-composite" or "eco-composite".

• Fashion & Textile Research Journal
• /
• v.11 no.2
• /
• pp.337-343
• /
• 2009

This study systematically investigated a method for extraction of safflower (Carthamus tinctorius Linnaeus) colorants by ultrasonic treatment. Compared to pigments productivity and cell wall structures of safflower after general and ultrasonic method, the ultrasonic method showed high extraction efficiency of safflower pigments due to destruction of safflower cell wall caused by high vibration energies. Microscopic analysis confirmed the hypothesis that the ultrasonic treatment of safflower caused its cell wall structure loosened and made efficient extraction of safflower pigments. And also, LC-MS/MS analysis revealed that productivities of the yellow and red safflower pigments by ultrasonic method were 21.9% and 14.6% higher, respectively, than those of pigments extracted by general method. The ultrasonic extracted yellow and red colorants could be used to dye not only natural fibers like cotton, silk and wool, but also synthetic fiber like nylon, and generally gave a better color tone than the general extracted colorants from safflower due to the affinities of red and yellow colorant on different fibers. As the yellow and red colorant were extracted by ultrasonic treatment in water, the K/S value on of 550/440nm of cotton and rayon was increased but in the case of silk and wool the change of this value was almost not detected. Finally, this technique might provide a solution to establish reproducibility and standardization for the extraction and dyeing methods on fabrics.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.47 no.6
• /
• pp.147-153
• /
• 2015

Wet-tissue has been used for baby wipe, cleansing pads, industrial wipes, pain relief, personal hygiene, pet care, and healthcare at home, care facilities, restaurant, and hospital. Raw materials of wet-tissue are mainly natural fibers and synthetic fibers such as cotton, rayon, PET (polyethylene terephthalate) and so on. In this study, electrolytic water of NaCl solution was used as fluid in wet-tissue, and the effect of raw materials on antibacterial rate of wet-tissue was investigated. Rayon (100%) showed an excellent antibacterial rate compared with cotton (100%) and rayon:PET (50:50). Antibacterial rate increased as Cl concentration of electrolytic water increased. Absorption of rayon:PET (50:50) was uneven and antibacterial rate of wet-tissue slightly increased by increase of Cl concentration. Antibacterial rate of wet-tissue was 100% under the conditions of more than 1.5 mL of electrolytic water dosage, and dropped under 50% after storage period of 48 hours.

• Journal of Fashion Business
• /
• v.7 no.3
• /
• pp.60-70
• /
• 2003

Textile scientists have regarded the material appearance of natural fibers, especially that of silk or wool fibers, as the benchmark for reinventing the look and feel of the long term, friendly companion of mankind. The appearances or textures of the materials surrounding us in everyday life have long been interesting topics to many people.from scholars to painters. Even the simplest questions may require careful pondering. Why is the silk fabric so lustrous with subtlety? Recently, appearance models have become increasingly important in textile products. They are needed to model and simulate different models. In this study, the optical characteristics of filament yarns and knitted fabrics were investigated using images taken at various angles and illumination conditions. Then the images were analyzed using some image analysis techniques, such as thresholding and measuring luster blobs. The anisotropic nature of the filamentous specimens was studied based on the images acquired at different incident illumination and observing angles with several alignment positions of the fabric specimens. A few cylindrical models were generated using commercially available software, Rhinoceros, and then on the models, a ray-tracing algorithm based on a software, POV-Ray, was applied to simulate the appearance or lustrous images of the monofilament models.

• Journal of Sericultural and Entomological Science
• /
• v.41 no.2
• /
• pp.116-121
• /
• 1999

This study was aimed to explain the essence of Hydroxylammonium hydrochloride(H.A.) effect on degummed silk fiber increasing the colour sites due to oxime generating reaction. H.A. in aqueous solution caues to increase the amount of [H+] and reduce pH values as the concentration of H.A. increases. The rate of [H+] absorption of silk fiker in acidic solution differs on the basic of solution pH and shows a specific uptake in each pH, the lower the pH of solution, the higher the amount [H+] absorption. The pH of solution after treating of silk fiber in H.A. and HCl, showed more remaining [H+] in H.A. solution due to [H+] releasing under the procedure of oxime production. Also it was revealed that in higher concentration of H.A. the reaction for oxime fixation in silk fiber carried out stonger and as a result the bigger gap with acid uptake curve appeared. FT-IR analysis of silk fiber treated with H.A. revealed the creating of intermolecular H-bond at the 2,981-2.930 cm-1, which was not appeared for nontraeted silk fibers and shows H-bond between N-OH group in oue chain and C=) group in another chain of silk protein. Colourimetry of dyed silk fiber after H.A. tratment showed that the silk fiber treated with the high concentration of H.A. compare to low concentration, absorbed more dyeing molecules and so Showed less percontage of Whiteness.

• Advances in aircraft and spacecraft science
• /
• v.6 no.2
• /
• pp.157-168
• /
• 2019

The production of nonwoven fabrics from natural fibers is already expanding at an industrial level for simple curvature semi-structural part in the automotive industry. To develop their use for technical applications, this paper provides an experimental study of the mechanical behavior of flax-fiber nonwoven preforms. A comparison between different sets of carded needle-punched nonwoven has been used to study the influence of manufacturing parameters such as fibers' directions, the area and the needle punching densities. We have found that the anisotropy observed between both directions can be reduced depending on these parameters. Furthermore, this work investigates the possibility to form double curvature parts such as a hemisphere as well as a more complex shape such as a square box which possesses four triple curvature points. We propose a forming process adapted to the features of the nonwoven structure. The purpose is to determine their behavior under high stress during various forming settings. The preforming tests allowed us to observe in real time the manufacturing defects as well as the high deformability potential of flax nonwoven.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.4 no.3
• /
• pp.9-15
• /
• 2002

Compared with synthetic dyes, natural dyes have inferior colorfastness as a result of the exposure of the material to any environment that may be encountered during the processing, testing, storage, display or use of the dyed materials. Especially, colors on fabrics fade excessively after washing. Therefore, it is problem to infer the historic textiles with natural-dyed fabrics. The object of this study is to analyse the factors affected to colorfastness and color change during washing. In experimental, fifteen natural dyes were dyed by the Korean traditional dyeing methods onto natural fiber fabrics: cotton, silk, ramie, and flex. Total 49 dyed fabrics in combination with dyes and fibers were used for the specimen. The Launder-Ometer was used for evaluating the effects of exposure to repetitive washing from 1 to 20 washing cycles (KS K 0430). Color difference(ΔE) in the CIEL＊A＊B＊ color-order system were determined by spectrophotometer at 100 bserver. Washing caused significant changes in the color of natural-dyed fabrics. The degree and nature of color changes on the fabrics were dependent on the combination of fiber and the dye type used. The groups of violet(Lithospermum erythrorhizon Sieb.et Zucc) and black color(Ailanthus altissima Swingle, Phus trichocarpa Miq) yielded excellent colorfastness to repetitive washing. The group of indigo blue color(Polygonum tinctorium Lour.) was also very resistant to color change in washing except silk. Whereas the dye groups of Red, Yellow, Orange, Brown colors indicated greatest changes in color, particularly Carthamus tinctorius L.

• Korean Journal of Human Ecology
• /
• v.22 no.2
• /
• pp.365-374
• /
• 2013

The purposes of this study were to evaluate the color characteristics and color sensibility of mulberry/cotton blended fabrics dyed with indigo, the natural dye, and analyze effects of them on color preferences. The values of CIE $L^*$, $a^*$, $b^*$ $C^*$, h were calculated for the color characteristics of indigo-dyed fabrics, and their hue, value, and chroma were calculated according to the Munsell color system. Fifty male and female college students evaluated the color sensibility of nine types fabrics dyed with indigo on a seven-point scale. The data were analyzed by descriptive statistics, factor analysis, Kruscal-Wallis test, correlation analysis, and regression analysis. The mulberry/cotton blended fabrics naturally dyed with indigo showed the characteristics of PB color tones, low value, and low chroma. The color sensibilities of fabrics dyed with indigo were classified into four factors: 'classic', 'sporty', 'elegant' and 'natural'. There were significant differences according to the fibers and the repeating times of dyeing in the color sensibility for the fabrics. Cotton fabrics were evaluated to be more classic, sporty, elegant, and natural than the mulberry/cotton blended fabrics, and the deeper the color, the more classic, sporty, and elegant the fabric was evaluated. The students preferred the indigo dyed fabrics which have more classic, sporty, and natural sensibility. There were significant relationships between the color sensibilities and colorimetric properties of the fabrics dyed with indigo. The color preferences of the dyed fabrics with indigo were found to be influenced by the 'classic', 'sporty', 'natural' of color sensibility.