Youngmi Park

The eco-friendly surface modification of textiles for deep digital textile printing by in-line atmospheric non-thermal plasma treatment

This study evaluated the potential application of an atmospheric plasma (AP) treatment as a pre-treatment for digital textile printing (DTP) of polyester (PET) fabrics and cotton, in order to determine its viability as an alternative to the usual chemical treatment. The surface properties of the AP-treated fabrics were examined through scanning electron microscopy (SEM) and contact angle, and the physical properties, such as electrostatic voltage and water absorbance, were tested. The properties of cotton and PET with the AP treatment were found to be dependent on number of repetitions and electric voltage. Although no remarkable surface differences were observed by SEM in the fabrics before and after treatment, the static contact angle of the PET after AP treatment was decreased from 85 ° to 24 ° at wave. In addition, the charge decay time decreased as the voltage and number of treatments increased. The absorption height of PET changed after exposure to 7 mm with increasing measurement time. The K/S with and without the AP pre-treated and DTP finished cotton was better than that with the usual chemical modification. In PET, the 0.5 kW and 1 time AP-treated specimen showed the highest K/S values.

Preparation and Application of Polymer-Composited Yarn and Knit Containing CNT/Ceramic:

The properties and light-heating function of a knit prepared by the composite spinning of carbon nanotubes (CNTs) and an inorganic ceramic were examined. The CNTs and ceramic were mixed and polymerized in a master batch (MB) and the MB chip was then melt spun to prepare the CNT/ceramic-composite yarn (LH-Yn) and single-jersey knits (LH-Knit). The properties of the LH-Yn and LH-Knit were compared with those of the regular polyester yarn (PET-Yn) and polyester knit (PET-Knit). The contents of carbon in the CNTs by energy dispersive X-ray spectrometer, scanning electron microscopy, tensile and tear performance, thermal insulation, air permeability (AP), water vapor permeability (WVP), and far-infrared (FIR) emissivity were analyzed. The result showed that the surface temperature of the LH-Knit was much higher than that of the PET-Knit. The measured WVP, AP, and FIR emissivity were also slightly higher in the LH-Knit, but the difference was not significant.

Study of Moisture and Thermal Transfer Properties as a Function of the Fiber Material Variation

The properties of moisture transfer and the comfort of mesh-structured fabrics with various knit compositions and properties were investigated. The comfort effects of the double knitted fabrics combined with different cross-shaped fibers composed of dyeable-polypropylene (PPd) and regular polyester (PET) double-knitted fabrics were studied. A series of PET, PPd, Coolmax® (Cm) with single knitted fabrics and PPd/Cm with double knitted fabrics were evaluated to determine the physical properties and wearing performance for comfortable clothing. To compare the structural properties involving the vapor transfer of 4 types of fabrics with different fiber compositions, fiber types, weights, and thicknesses, the surface structure and pore characteristics were evaluated by scanning electron microscopy and a capillary flow porometer. The properties of moisture transfer were tested using vertical wicking and gravimetric absorbent testing system (GATS). In addition, the comfort performance measured by the thermal insulation value (Rt) and moisture permeability index (im) with a thermal manikin in a conditioned walk-in environmental test chamber was predicted. The result showed that the PPd/Cm sample has potential applications as good comfort fabric materials.

Characteristics of double-layer coated fabrics with and without phase change materials and nano-particles

Stability in a low temperature environment is needed for a textile to be used as winter wear. This research was presented the characteristics of fabrics by double-thin-layered coating with and without phase change materials (PCM) and several nano-sized inorganic particles (N-particles). Silica, Ag, Zr, and carbon types of N-particles were used for investigating the N-particles effect. For the experimental method, the PCM and N-particles were coated consecutively in the wet and dry coating process, respectively. The N-particles on the surface of the coated fabrics were confirmed by energy dispersive spectroscopy (EDS), and after double-layer composite coating, the adhesion durability, water vapor permeability, water penetration resistance, DSC, thermographic photography, far infrared (FIR) emission effect, and the thermal insulation of the coated fabrics were tested for investigating the performances. Their compatibility and adhesion were superior when the add-on of N-particles was 10 %. From the DSC reproducibility results, we verified that the N-particles coated fabric preserved its thermal stability by absorbing latent heat. On the other hand, the FIR emission rate and energy of the Ag N-particle based sample were not better than the control sample.

Development of moisture transition ability on porous complex structured woven fabric with convergence of pattern, porosity, and plasma technology

A porous complex structured woven fabric was manufactured to maximize the moisture transition ability of the prepared fabric by increasing the absorptive property of the fabric through surface modification using plasma, which is a dry modification method. Porous single and complex structured woven fabrics were produced by applying pattern, porosity, and plasma technology, including fabric patterning based on the sheath/core complex structure, the formation of porosity by removing the weft thread or warp thread, and hydrophilic surface treatment using plasma and the improvement in water absorption of different fabrics by the porous and plasma treatment was investigated. Therefore, two different types of fabrics were prepared. One is the porous single structured FAB-SINGLE fabric which was taken out in the direction of the Polyester (PET) warp thread of a general single structure to form a porous. Another is FAB-COMPLEX fabrics that the water-soluble polylactic acid (PLA) yarns with a 1.7 to 2.0 times longer absorption distance than that of PET yarns were inserted into the weft threads, and the PLA yarns were dissolved in a solvent to form the porous complex fabric. And then the physical properties and water absorption of the two types of fabric were compared after the plasma treatment. The results showed that when the FAB-SINGLE fabric, which has porosity induced by the removal of the warp threads in a certain gap, was plasma treated for 5 min, the contact angle was decreased to the extent that a measurement of the contact angle was impossible, whereas the fabric that had not undergone a plasma treatment had a contact angle of 123.6 o. The contact angle of the FABCOMPLEX with porosity caused by the dissolution of the PLA yarns was reduced from 76.8 o to 0 o after 3 minutes of a lowtemperature plasma treatment, indicating that the hydrophilic property was increased. In addition, the water absorption measurements showed that the absorption height was increased from 2.3 cm of the fabric sample that had not been treated with plasma to the highest absorption height of 8.3 cm, suggesting that the water absorption also increased with the improvements in moisture transition ability by the plasma treatment. The physical tensile strength of the fabrics was not changed by the plasma treatment, despite the changes on the fabric surface, suggesting that the combination of double complex structures and the plasma treatment helped improve the water absorption.