• Fibers and Polymers
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• v.7 no.2
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• pp.169-173
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• 2006

Six nano disperse dyes were prepared using corresponding O/W nanoemulsions which were obtained with sodium laurylsulphate and caprylic triglyceride. The average particle size of the dyes prepared were in the range of $110{\sim}130nm$. Exhaust dyeing using nano dyes resulted in low exhaustion yields of $17{\sim}26%$ on regular polyester fiber and $28{\sim}38%$ on ultramicrofiber polyester. The observed low exhaustion yields of nano disperse dye can be explained by the solubilization of dye particles into surfactant micelles as well as the high stability of the nanoemulsions, these might reduce the capacity of dye uptake onto the fibers. However, higher K/S values of dyeings with nano dyes on ultramicrofiber sites compared to those on regular polyester sites suggested their potential to be more efficient dyes for finer denier microfiber polyesters.

• Fibers and Polymers
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• v.4 no.2
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• pp.66-70
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• 2003

Temporarily solubilized azo disperse dyes based on 1,2-substituted indoles were synthesized and characterized. Dispersant-free dyeing of polyester by using the synthesized dyes has been investigated. The colour yields of the dyes on the polyester fabric were found to be highly dependent on the dyeing pH, optimum results being obtained at pH 5. The dyes exhibited good to excellent fastness properties on polyester while lightfastness was moderate.

• Fashion & Textile Research Journal
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• v.20 no.1
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• pp.93-100
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• 2018

This study comparatively analyzed the changes in the dimensional stability and the mechanical properties of stretch knit fabrics associated with washings conditions in order to determine the most appropriate washing method. Polyester and spandex knit fabrics were washed 25 cycles with nine washing condition profiles that controled detergent, hardness. temperature and RPM. The knit fabrics with repeated washings were evaluated by dimensional stability and measured by the KES-FB system. Polyester and spandex fibers have good chemical resistance. However, the changes in the dimensional stability and the mechanical properties were observed in washed knit fabrics. After repeated washings, the knit fabrics washed in an alkali or neutral detergent had good dimensional stability compared with the knit fabric washed in functional detergent. The washed knit fabrics were extended, stiff, rough, and had a smaller volume. The changes were the result of the rearrange of polyester fibers which twisted around spandex core and chemical interactions involving the detergent and the physical and mechanical forces of washing. Especially, using an alkali detergent resulted in increased stiffness and roughness of the knit fabric. In conclusion, the washing in water with low hardness and a neutral detergent can minimize the changes in dimensional stability and mechanical properties of polyester and spandex knit fabric.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.157-169
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• 1996

Polyester yarns and fabrics containing three levels of $TiO_2$ delusterant were hydrolyzed with NaOH and examined for physical and morphological changes. The mechanical propertis and hand values of alkaline hydrolyzed polyester fabrics were measured using KES-FB system. Also, the relationship between the morphology and the mechanical property of alkaline hydrolyzed polyester fabrics was analyzed. The results are as follows: 1. At an initial stage of alkaline treatment, the concentration of $TiO_2$ did not affect the weight loss of the treated yarns. But by increasing treatment time, the effect of the concentration of $TiO_2$ on the weight loss of the fiber became more pronounced. The weight loss were increased in the following order; fulldull> semidull> clear 2. The effect of hydrolysis on yarn tensile strength seems to be more related to the size of the pits on the fibers rather than the number of pits. 3. Axially oriented pits occurred along the hydroyzed, delustered fiber surfaces, while such pitting was absent on hydrolyzed fiber containing no $TiO_2$. The number of voids across the surface of a fiber increased with an increase in the amount of TiOa incorporated into the fibers. The size of the voids depended on the treatment time of hydrolysis rather than the concentration of TiOa. 4. The mechanical properties and hand values of polyester fabrics were changed by alkaline treatment but were identical regardless of the concentration of TiOa. While the mechanical properties of polyester fabrics depended on the structural change of the fibers and the yarns within the fabrics as the fiber diameter became progressively smaller rather than the size and number of pits.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.273-276
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• 2002

The fiber formation of conventional melt spinning is extruded by forcing the polymer melt through a spinneret by pumping mechanism usually involving high pressure. This is followed by cooling, solidification and appropriate drawing of the fiber. The spinning process is broadly applicable to polyolefin, polyamide, polyester and indeed the whole range of fibers forming thermoplastic polymers. (omitted)

• Korean Journal of Human Ecology
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• v.8 no.1
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• pp.125-134
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• 1999

The purpose of this study was to investigate the effects of heat transfer characteristics of fibers on the Qmax of insulating nonwovens. The effects of fiber type, moisture content, washing cycles on the Qmax were observed. The correlations between Qmax measured by KES-F7 system and subjective warm/cool touch perception test was analyzed. The results obtained were as followed: 1. Heat transfer characteristics of fibers effected on the Qmax of insulating nonwovens. 2. Moisture transport properties of fibers effected considerably on the Qmax of nonwovens and the increasing rate of Qmax by increasing moisture content was much higher at wool than polyester. 3. As a result of subjective perception test, subjective warm/cool touch and wettness of wool nonwoven was increased obviously by increasing moisture content. 4. At the same moisture content, wool nonwoven showed higher subjective cool touch and wetness than polyester. 5. In the physical properties of nonwovens, thickness was the most effective factor on the Qmax of insulating nonwovens.

• Polymer(Korea)
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• v.29 no.2
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• pp.190-197
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• 2005

Nanocomposites of three different polyesters with dodecyltriphenylphosphonium-montmorillonite $(C_{12}PPh-MMT)$ as an organoclay are compared with their thermal properties, mechanical properties, and morphologies. Poly (butylene terephthalate) (PBT), poly(ethylene terephthalate) (PET), and poly(trimethylene terephthalate) (PTT) were used as matrix polymers in the fabrication of polyester nanocomposite fibers. The variations of their properties with organoclay content in the polymer matrix and draw ratio (DR) are discussed. Transmission electron microscopy (TEM) micrographs show that some of the clay layers are dispersed homogeneously within the polymer matrix on the nano-scale, although some clay particles are agglomerated. We also found that the addition of only a small amount of organoclay is enough to improve the thermal stabilities and mechanical properties of the polyester nanocomposite fibers. Even polymers with low organoclay contents $(<5\;wt\%)$ were found to exhibit much higher strength and modulus values than pure polyester fibers. In the cases of all polyester hybrid fibers, the values of the tensile mechanical properties were found to decrease linearly with increasing DR. However, the initial tensile modulus of the PTT hybrid fibers were found to be independent of DR.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.7
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• pp.1121-1127
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• 2009

This study presents an eco-friendly and one-step finishing method for modifying fiber property that reduces fiber damage in wool/polyester blend fabrics. Lipase from aspergillus oryzae is used in this experiment. The enzymatic treatment condition is optimized by measuring the relative activity of lipase depending on pH level, temperature, concentration of lipase, and treatment time. The concentration of $CaCl_2$as an activator is determined by the characteristics including whiteness, water contact angle (WCA), and dyeing property. The modified properties of lipase treated fabrics are tested for pill resistance and surface morphology. The results are described as follows: the optimum condions for lipase treatment constitute a pH level of 8.0, treatment temperature of 40$^{\circ}$$_C$, concentration of lipase at 100% (o.w.f), and a treatment time of 90 minutes. $CaCl_2$helps in raising lipase activation, and the optimum concentration is 50mM. The whiteness, wet ability, and pill resistance of lipase treated fabrics improves as compared to the control. The dyeing property of lipase treated fabrics improved by 53.5% after using the one-bath dyeing method. This means that lipase treatment can save time and cost during the dyeing process since lipase treatment modifies wool and polyester fibers. The surface of lipase treated wool fibers do not exhibit any change, however voids and cracks manifest on the surface of lipase treated polyester fibers.

• Fibers and Polymers
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• v.4 no.4
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• pp.204-209
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• 2003

The effect of padding solution on the microwave heat dyeing of polyester fabric was studied extensively. Polyester fabrics were impregnated in aqueous urea solution and aqueous sodium chloride solution for 10 min and then dyed for 7 min by microwave apparatus (2450 MHz, 700 W) under optimum conditions which provide good exhaustion. Aqueous solutions of urea and sodium chloride showed more effective than water as a padding solution for microwave heat dyeing. The type of solvent added in padding media and its concentration significantly affects the K/S values of dyed polyester fabric. Added solvents such as n-hexane, acetone, and dimethyl formamide were also more effective than 100 % water as padding media for the microwave heat dyeing. It is supposed that the effect of used solvents on dyeing property of polyester fabrics depends on the solubility parameter difference between solvent and polyester fabric.

• Textile Coloration and Finishing
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• v.13 no.4
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• pp.256-263
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• 2001

Polyester fabrics were irradiated by UV produced by the low pressure mercury lamp. UV irradiation broke a C-H bond of PET fiber and caused the carbonyl groups on the fiber surfaces. Surface modification of PET fibers were accelerated by pretreatment with methanol, ethanol and acetone. The irradiated PET was dyed with basic dyes having cationic groups. The dye uptakes were proportional to irradiation times, and in inversely proportional to irradiation distances. The tensile strengths of PET fabrics decreased by UV irradiation. Washing fastness of PET dyeings were good, about 4-5 grade,andlightfastnesswerepoor, about l grade.