• Journal of Advanced Marine Engineering and Technology
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• v.33 no.1
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• pp.90-96
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• 2009

Injection molding process is one of the most important methods to produce plastic parts with high efficiency and low cost. Today, injection molded parts have been increased dramatically the demand for high strength and quality applications. This report investigates that the optimum injection molding condition for minimum of shrinkage. Molding shrinkage is occurred by several reasons such as thermal shrinkage, a hardening process and compressibility. This report concentrate on shrinkage by a hardening process. As Change a holding pressure and holding time, checked deflections of X, Y, Z directions by shrinkage based on same condition. In conclusion, it was found that holding pressure is stronger and holding time is longer, the deflection by shrinkage is smaller because injection molding needs enough time for cooling and high density. The FEM Simulation CAE tool. Moldflow, is used for the analysis of injection molding process.

• Fashion & Textile Research Journal
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• v.10 no.6
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• pp.1058-1063
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• 2008

The use of clothes dryers is increasing in Korea and throughout Asia, because of preference for the drum type washer dryer. Clothes dryers consume more energy than almost any other home appliance. This paper suggests efficient ways for drying laundry with condensing clothes drier. We dried cotton fabrics with the condensing clothes dryers and observed the energy input, temperature and RH of the dryer during the drying process. In the early stages of drying process, the air temperature inside the clothes dryer decreased and the RH and the drying time increased as the weight of fabrics increased. We found that it was important to consider the total weight of the fabrics that included heat-sensitive fibers. It took more than half the drying time and the energy input for a 2.5 kg load that it did for a 5 kg load. Therefore, drying larger one load was more efficient than divided smaller loads, because increasing the weight of the fabrics reduced the energy input per kg of drying clothes. The lower the initial moisture regains of the fabrics were, the lower the energy input and the drying time were. The energy input for spinning after washing was much less than that for drying in the dryer. Consequently, it is more efficient to reduce the moisture content of the clothes by lengthening the spinning time of the washer to reduce the energy consumption and the drying time. During the drying process opening the door twice for 30 seconds each time lowered the air temperature and the RH of the dryer, but did not affect the moisture regain of the fabrics, the drying time, and the energy input.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.2 s.161
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• pp.197-205
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• 2007

We investigated the effects of washing on the mechanical properties and hand values of spandex/cotton and cotton single jersey fabrics. These knitted fabrics were subjected to 30 laundering cycles with a drum-type washer and were followed by drying at $65^{\circ}C$ with a tumble dryer. The mechanical properties of the cotton knitted fabrics changed greatly during the first washing and then suffered no further change in their properties as the number of washing cycle increased. However, the properties of the spandex/cotton knitted fabrics changed continuously throughout all the washing cycles. The cotton/spandex knitted fabrics showed higher values in tensile and bending properties than did the cotton knitted fabrics, though both kinds of fabrics showed less difference in shearing, surface and compression properties. The spandex/cotton knitted fabrics which had proper density had a higher THV for winter underwear after 30 repeated washings than did the cotton knitted fabrics, and the THVs of both fabrics decreased with the increase in the number of washing cycles.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.947-958
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• 2008

To study the effect of a washing machine with silver nano technology on its detergency, the discoloring of the dyed clothes and the staining of standards adjacent fabrics were examined. As the laundry specimen, cotton fabric dyed with reactive dyes and Polyester fabric dyed with disperse dyes were chosen; and as the adjacent fabrics, undyed cotton. polyester and nylon fabrics were chosen. The colorfastness was evaluated after washing under conditions that those washing temperature, liquor ratio, detergency concentration and the type of water were varied. When the clothes were washed with the tap water contains silver ion, the deposition of silver compounds into the washed clothes was measured. As a results, after the washing in the various conditions, discoloring of the dyed clothes was not intense. The higher the washing temperature and the lower the liquor ratio, the larger the staining appeared on the white fabrics; especially for the white nylon fabrics. The concentration of detergent and the type of water affected hardly the colorfastness. After the repeated washing with the water contains silver, whiteness of the cotton and the nylon fabrics were lower than the result after the washing with the tap water, and a quantity of silver ions was found on the washed clothes.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.11
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• pp.1798-1811
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• 2010

This research evaluates the changes in the comfort-related properties of high-density fabric, such as moisture permeability and waterproofness, in order to assess the relative importance of laundry conditions for clothing properties after repeated laundering and suggest the best laundering conditions for high-density fabric through the identification of the most influential factor. A commercial high-density fabric was washed 25 times in a drum-type washer using nine different laundry conditions based on profiles derived from a fractional factorial design. To evaluate the changes in the comfort-related properties of the fabric, pore size, air permeability, water vapor transport, water repellency, and water resistance were measured. The comfort-related properties of the fabric deteriorated after repeated laundering by the damaged surface finish; in addition, the damaged surface also changed the pore size. As a result, the water repellency and water resistance decreased. The detergent was the most responsible factor to change the properties among the four factors of detergent, hardness, temperature, and RPM. The best laundering conditions for the fabric was a neutral detergent, soft water of 70ppm, a temperature of $15^{\circ}C$, and 30rpm.