• Fashion & Textile Research Journal
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• v.2 no.5
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• pp.398-404
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• 2000

We examined the effect of individual sweating responses on thermoregulatory responses induced by heat of sorption, immediately after the onset of sweating. The present study consists of two experiments. In experiment 1, made of 100% cotton (C) and 100% polyester (P) clothing were exposed in the chamber at ambient temperature (Ta) of $27.2^{\circ}C$ and relative humidity (rh) raised from 50% to 95% at five different increase rates of environmental vapor pressure (VP). The increase rate of clothing surface temperature (Tcs), peak Tcs and peak time showed significant correlation with the increase rate of environmental VP in C-clothing (p<0.05). In experiment 2, seven female subjects were studied during leg water immersion ($35-41^{\circ}C$) for 70min in Ta of 27.2 and 50%rh. There were significant positive correlations in the increase rate of clothing microclimate VP vs. changes in Tcs, skin blood flow, mean skin temperature and mean body temperature (p<0.05). The present results showed that individual clothing microclimate VP had significant effects on thermoregulatory responses induced by heat of sorption wearing C ensembles.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.5
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• pp.929-938
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• 2017

This research investigated the effects of cool touch fabrics on thermo-regulating physical properties and subjective evaluation using a 3D fitted women's T-shirts in wear test. Qmax, clothing microclimate, microclimate wettedness, thermogram and subjective vote were observed during rest-right after an exercise-rest protocol. As a result, there was no single determining physical variable to explain the reasons of cool sensations of T-shirts made of cool touch fabric across the entire protocol. Qmax could partly predict a wear sensation at the initial stage when only insensible perspiration was presented. Simultaneous observation of temperature/humidity gradient understand from the inside to the outside of the clothing layer or microclimate wettedness calculated using vapor pressure were helpful to figure out the performance of cool touch fabric, especially at the later stage of the protocol when sweating was excessive. It was especially difficult to connect thermo-regulating physical variables to the subjective evaluation during transient conditions such as 'right after exercise' stage. It is necessary to measure the amount of heat and moisture transferred from the skin to the outside of clothing along with the physical properties measured in this study to understand the detailed mechanisms of why a cool sensation is evoked from tight fitting T-shirts made of newly developed cool touch fabrics.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.228-238
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• 1996

The purpose of this study was to evaluate the effect of chacteristics of knit fabrics on the microclimate of the skin simulating system. To determine the effect of characteristics of knit fabrics, vapor state of sweat pulse was simulated in the closed system. Different contents of fibers such as cotton, wool and polyester with different yarn size and knit types were chosen for specimens. The changes of humidity and temperature of air layer in the simulated systems were measured. Buffering indices, $K_d$ and $\beta_r$, were determined by considering $\alpha_p, \DeltaP_{max}, t_{max}, and tan\beta$. Physical properties of knit fabrics such as thickness, porosity, air resistance and moisture vapor transport were measured. Results showed that vapor pressure of wool was lower than cotton or polyester This was attributed to the hydrophilicity of wool which absorbed moisture rather quickly and retained in the knit fabric. The time to decrease vapor pressure was faster for polyester than cotton or wool. As a result, $K_d$ was in the order of wool> polye, item> cotton. $\beta_r$ of wool was rower than cotton or polyester due to its lowers porosity and slower desorption rate. For the yarn size, $K_d$ was in the order of 80's> 60's> 30's; thinner and lighter yarn showed better water vapor transport property. For knit type, buffering capacity of single jersey was better than interlock knit fabric. Statistical analysis showed that the air permeability was the most influential factor far the water vapor transport properties.

• The Korean Journal of Community Living Science
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• v.25 no.4
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• pp.549-556
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• 2014

This study evaluates the thermal insulation and evaporative resistance of a waterproof and breathable garment system and determines the factors influencing its thermal performance. The experimental garments were composed of underwear (shirts with 100% wool and 100% polyester) and outerwear (jackets and pants with a vapor-permeable membrane and a vapor-impermeable membrane). Data on clothing insulation in a dry condition ($10^{\circ}C$) and a wet condition ($10^{\circ}C$, 40% R.H.), evaporative resistance ($34^{\circ}C$, 40% R.H., and $10^{\circ}C$, 40% R.H.), and microclimate vapor pressure were collected and analyzed. According to the results, the thermal insulation of the experimental garment system ranged 1.27~1.40 in the dry condition and 0.40~0.89 in the wet condition at $10^{\circ}C$. Evaporative resistance ranged $41{\sim}525m^2Pa/W$. A decrease in thermal insulation by wetting underwear ranged 31~67% in the cold condition ($10^{\circ}C$). The breathability of the outer garment influenced the decrease in thermal insulation by wetting. The type of underwear fiber influenced the decrease in thermal insulation only when it was used with breathable outerwear. The vapor-permeable outerwear sample with polyester underwear (P_Perm) showed a larger decrease in insulation than that with wool (W_Perm). The evaporative resistance of the vapor-permeable ensemble showed no effect of underwear in the warm condition ($34^{\circ}C$), but polyester underwear showed lower evaporative resistance than wool in the cold condition ($10^{\circ}C$). The vapor-impermeable ensemble showed no difference in evaporative resistance between polyester underwear and wool underwear in both conditions. Future research should consider various clothing ensemble combinations and environmental conditions and evaluate wear comfort by using human subjects.