• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.168-174
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• 1996

Dyeing on silk with vat dyes which shows good color fastness at strong alkaline conditions were newly examined. The optimum conditions of dyeing bath to prevent the damage on the tensile strength and elongation were sodium hydroxide(NaOH) 10g/l, sodium hydrosulfite(Na2S2O4) 20~22 g/l, for 30 min at 5$0^{\circ}C$. The color yield of silk fabrics was increase according to the concentration of NaOH and Na2S2O4, but decreased at higher concentration than that of NaOH 10g/l and Na2S2O4 22g/l. The vat dyeings showed excellent color fastness against washing and light, compared with the conventional dyeings.

• Fibers and Polymers
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• v.2 no.4
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• pp.190-195
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• 2001

Additives, such as sodium perborate and borax, were examined in dialdehyde wrinkle resistant finishing of cotton. Results indicated that the whiteness index(WI) of cotton treated with dialdehyde and additive showed about 90% of WI of the untreated cotton but with decrease in wrinkle recovery angle (WRA) due to inhibition effect of these additives. Effect of additive on the WRA reduction was more prominent with glutaraldehyde than with glyoxal. Reduction in WRA of cotton treated with both dialdehydes and boron compound was minimized by simultaneous addition of formic acid in the bath. Addition of formic acid was also generally beneficial in maintaining WI retentions after 8 months storage. Furthermore, boron compounds were also effective in improving retentions of mechanical properties. By FTIR analysis the residual aldehyde group was detected on the dialdehyde-finished cotton, whereas no peak was shown by addition of boron compounds. This suggested that the residual aldehyde group was a main cause of fabric yellowing on the dialdehyde-finished cotton. Dialhehyde with boron compound, therefore, can be used to replace a conventional formaldehyde-containing wrinkle resistant finishing of cotton.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.180-183
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• 2009

Composite bipolar plates offer several advantages of low cost, light weight, and ease of manufacturing compared to traditional graphite plate. However, it is difficult to achieve both high electrical conductivity and high flexural strength. In this study, the hybrid carbons filled epoxy composite bipolar plates were fabricated to test electrical conductivity and flexural properties. Graphite powders were used as the main conducting filler and continuous carbon fiber fabrics were inserted to improve the mechanical properties of the composite. This hybrid composite showed improved in-plane electrical conductivity and flexural property. The moldability of the hybrid composite was also improved comparing to the continuous prepreg composite. This study suggested that the continuous carbon fiber inserted graphite/epoxy composites can be a potential candidate material to overcome the disadvantages of conventional graphite composite or continuous prepreg composite bipolar plates.

• Textile Coloration and Finishing
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• v.6 no.3
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• pp.67-73
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• 1994

The adsorption behaviors of acid dye and disperse dye on silk and nylon fabrics were examined, in one bath dyeing system on silk/nylon blend fabric with disperse dyes and acid dyes. In the dyeing of nylon fabric with C. I. Disperse Red 19 (Red 19) and C. I. Disperse Red 60 (Red 60), dye uptake of Red 19 was higher than that of Red 60. When silk/nylon blend fabric was dyed with Red 19 and Red 0, the dye uptake on nylon was influenced by the ffinity of the dye to the silk fabric. In the dyeing of silk/nylon with C. I. Acid Blue 80 and C. I. Acid Yellow 121, solid shade could not be obtained with the conventional method but could be obtained with the dyeing resist agent for nylon. There was not any relationship between K/S value and Munsell value, but Munsell value tended to change with the K/S value.

• Textile Coloration and Finishing
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• v.21 no.6
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• pp.46-55
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• 2009

Some phthalimidyl azo dyes containing N,N-diethyl or N,N-di($\beta$-methoxycarbonylethyl) group have been attempted to apply onto two kinds of polyurethane based materials and rationalize their dyeability and fastness comparing with those of some commercial disperse dyes. Phthalimidyl azo dye showed 66~98% of exhaustion yield at $120^{\circ}C$ by a conventional exhaust dyeing method. The dyeings were found to have a higher wash fastness with both fabrics in comparison with those of commercial dyes which indicates lower thermomigration and efficient alkali clearable properties of phthalimidyl ring and/or diester group during post-dyeing process.

• Journal of the Korean Society for Railway
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• v.3 no.2
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• pp.92-99
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• 2000

Composites are very useful material for light train carbody due to its high specific strength and lightweight characteristics. The composites, called 3-D board, are developed with a special stitching method. In this process, the glass fiber fabrics of skin material and foam core material are stitched together with glass fiber thread. The glass thread in Z-axis turns into FRP form. The conventional delamination problem can be solved with 3-D sandwich structure. In addition, with the lower density of foam, the weight of the panel and the operation expenses can be highly reduced. To evaluate the usefulness of the 3-D board, the double-deck light train carbody is studied. The stress analyses are carried out under various loads and boundary conditions with FEM Code, ANSYS. On comparing with the aluminum carbody, 3-D board carbody can be reduced by about 2 ton for the total weight of carbody.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.166-175
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• 2005

Health effects associated with metal working fluid (MWF) exposures include dermatitis, respiratory disease, hypersensitive pneumonitis, and asthma. Frequently, occupational exposures to MWFs are controlled by ventilating an enclosure with an air cleaning unit that includes a fan preceded by various kinds of filtration. There are several kinds of air cleaning units used in machining centers. But the associated troubles have hindered from efficiently using these devices. The main problem is the relatively short period of filter replacement. The reason is that the air cleaning units usually do not have the de-oiling systems, thus leading the earlier clogging of filters and reducing the flow rate of hood. Thus, the first stage of study was conducted to overcome this problem by developing the new oil mist collector equipped with the easy de-oiling system. The principle of de-oiling is that the centrifugal force generated by spinning the drum covered by filter fabric separates oils from the filter fabric. It would be very similar to the spin-dry laundry. By adopting this de-oiling technique, the problems associated with the conventional oil mist collectors could be solved. Several tests/analyses were performed to make the lab-scale oil mist collector. The collection efficiencies and the de-oiling efficiencies of commercially available filter fabrics were tested. Subsequently, the endurance test were conducted by observing SEM photos of filter fabrics and measuring tensile strength/expansion coefficient after spinning the filter drum for 20 minutes at the different rotation speeds. By doing these experiments, the most appropriate filter fabric and rotation speed/duration were selected. Finally, the new oil mist collector was designed. In the near future, this device must be tested in the real machining center.

• Textile Coloration and Finishing
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• v.32 no.1
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• pp.38-43
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• 2020

To overcome the harmful effects caused by conventional oxidative hair dyes, natural colorants becomes more popular in the hair dyeing. By extracting Sagassum fusiforme powders with aqueous alkaline solution as a solvent at 130℃ for 60 minutes, a fucoxanthin concentration of up to 216㎍/ml can be obtained. UV/Vis analysis was used to prove the presence of fucoxanthin in the extract powder. A K/S value of 23.8 can be obtained when wool fabrics were dyed with the extract at 120℃ for 60 minutes under pH 2. The color fastness properties of the dyed wool fabrics were very good as indicated by rating 4 for laundering(color change), rating 3 or higher for rubbing, and rating 5 for light irradiation. The dyed wool fabric was found to have antimicrobial activity against Staphylococcus aureus. The antioxidant and antimicrobial activity of the Sagassum fusiforme extract can be an effective functional hair colorant. Hair dyeing with the extract formulation at 45℃ for 40 minutes under pH 5 accomplished a K/S value of 8.9. The color fastness of the dyed hair showed rating 3 against light irradiation, which increased to rating 5 with after-mordanting of tannin acid.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.946-951
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• 2005

In this wort plasma treatment was evaluated as an alternative clean desizing technology. Size materials such as PVA(polyvinyl alcohol), PACL(polyacrylic acid esters) and their mixture on PET(polyethylene terephthalate) fabrics were treated by $N_2$ and $O_2$ plasma. $O_2$ plasma was more efficient in size removal than $N_2$ plasma, and the removal of PVA was higher than that of PACL. SEM(scanning emission microscopy) pictures of the plasma treated samples directly proved the disappearance of sizing agents. After $O_2$ plasma treatment, the PET fabrics were subjected to conventional desizing process. Compared with untreated fabrics, the desizing effluent from the treated fabrics gave lower TOC, COD and $BOD_5$ values. This indicates plasma treatment not only serves to directly remove sizing agents but also offered several advantages by changing the chemical properties of sizing agents. Lastly, the effect of plasma desizing process on dyeing was examined using color difference and dyeing fastness tests. The CCM(computer color matching) results showed rotor difference between PET fabric desized by $O_2$ plasma treatment for 20 min and reference PET fabric desized by the conventional wet desizing process was around 1. This suggests the treated PET fabric can be directly subjected to dyeing process without any additional process. The plasma treated fabric also gave a good result of dyeing fastness so that grades of laundering, crocking, heat and light fastness were same or even better than the reference PET fabric did.

• Fashion & Textile Research Journal
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• v.9 no.6
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• pp.671-678
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• 2007

Formulations of compact and supercompact heavy-duty detergents, which are being used widely around the world, differ from those of conventional heavy-duty detergents. Significant differences in composition exist between the compact detergents and the conventional detergents. The compact detergents have a higher content of surfactants, oxygen bleach and enzymes than the conventional detergents. We have studied to find the most effective washing conditions of artificially soiled cloths with a commercial, supercompact, heavy-duty detergent and a drum type washing machine which is becoming the preferred type in Korea. Moreover, we have studied the washing performance with an impeller type washing machine, which has heretofore been the most popular type in East Asia. With the drum-type washing machine, washing performances improved as the washing temperatures went up and the washing times were lengthened. Though the rate of soil removal with a double recommended dosage was higher than with the recommended amount at $20^{\circ}C$, the effects of the higher dosage decreased as the washing temperatures increased. Finally, the washing performances with the two different dosages were the same at $60^{\circ}C$. The washing performances at $40^{\circ}C$ with the recommended dosage for 90 minutes were the same as with the double recommended dosage for 45 minutes. The soil removal efficiencies with the impeller-type washing machine were much lower than those of the drum-type washing machine. The reasons for this were the higher bath ratio that led to the lower concentration of wash liquor, the shorter washing time, and the lower washing temperature.