• Journal of the Korea Fashion and Costume Design Association
• /
• v.4 no.3
• /
• pp.9-15
• /
• 2002

Compared with synthetic dyes, natural dyes have inferior colorfastness as a result of the exposure of the material to any environment that may be encountered during the processing, testing, storage, display or use of the dyed materials. Especially, colors on fabrics fade excessively after washing. Therefore, it is problem to infer the historic textiles with natural-dyed fabrics. The object of this study is to analyse the factors affected to colorfastness and color change during washing. In experimental, fifteen natural dyes were dyed by the Korean traditional dyeing methods onto natural fiber fabrics: cotton, silk, ramie, and flex. Total 49 dyed fabrics in combination with dyes and fibers were used for the specimen. The Launder-Ometer was used for evaluating the effects of exposure to repetitive washing from 1 to 20 washing cycles (KS K 0430). Color difference(ΔE) in the CIEL＊A＊B＊ color-order system were determined by spectrophotometer at 100 bserver. Washing caused significant changes in the color of natural-dyed fabrics. The degree and nature of color changes on the fabrics were dependent on the combination of fiber and the dye type used. The groups of violet(Lithospermum erythrorhizon Sieb.et Zucc) and black color(Ailanthus altissima Swingle, Phus trichocarpa Miq) yielded excellent colorfastness to repetitive washing. The group of indigo blue color(Polygonum tinctorium Lour.) was also very resistant to color change in washing except silk. Whereas the dye groups of Red, Yellow, Orange, Brown colors indicated greatest changes in color, particularly Carthamus tinctorius L.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.57.2-57.2
• /
• 2011

Dye-sensitized solar cells (DSSC) have recently been developed as a cost-effective photovoltaic system due to their low-cost materials and facile processing. The production of DSSC involves chemical and thermal processes but no vacuum is involved. Therefore, DSSC can be fabricated without using expensive equipment. The use of dyes and nanocrystalline $TiO_2$ is one of the most promising approaches to realize both high performance and low cost. The efficiency of the DSSC changes consequently in the particle size, morphology, crystallization and surface state of the $TiO_2$. Nanocrystalline $TiO_2$ materials have been widely used as a photo catalyst and an electron collector in DSSC. Front electrode in DSSC are required to have an extremely high porosity and surface area such that the dyes can be sufficiently adsorbed and be electronically interconnected, resulting in the efficient generation of photocurrent within cells. In this study, DSSC were fabricated by an screen printing for the $TiO_2$ thin film. $TiO_2$ nanoparticles characterized by X-ray diffractometer (XRD) and scanning electron microscope (SEM) and scanning auger microscopy (SAM) and zeta potential and electrochemical impedance spectroscopy(EIS).In addition, DSSC module was modeled and simulated using the SILVACO TCAD software program. Improve the efficiency of DSSC, the effect of $TiO_2$ thin film thickness and $TiO_2$ nanoparticle size was investigated by SILVACO TCAD software program.

• Textile Coloration and Finishing
• /
• v.17 no.1
• /
• pp.14-19
• /
• 2005

Study on the use of enzymes for textile wet processing has been very active. The exploratory research conducted herein is related to the bioscouring process for cotton fabric. The optimum concentration of alkaline pectinase(BioPrep) was in the range of 0.05～0.2 g/l, the proper treatment time was 30～60 minutes, the appropriate treatment temperature was $60^{\circ}C$ for both the batch method and the padding method. The simultaneous desizing/bioscouring by padding method did not give water absorbency as good as the bioscouring after desizing. Color of fabrics which were bioscoured and dyed with direct dyes and a reactive dye was just a little darker than that of NaOH scoured one. K/S and Lab values of the bioscoured fabrics, regardless of the degree of water absorbency, were quite similar to each other.

• Textile Coloration and Finishing
• /
• v.31 no.4
• /
• pp.258-267
• /
• 2019

Synthetic suede without PFCs(perfluorinated compounds) are followed by subsequent high temperature treatment. But migration fastness of synthetic suede may be reduced due to sublimation of disperse dyes that results from the high temperature treatment. Therefore, in this study, chitosan treatment was used to improve the migration fastness before polyurethane dipping process. Polyester fiber was treated with sodium hydroxide aqueous solution before chitosan processing. This samples treated with a chitosan concentration upto 0.5% were dyed and coated with PUD(polyurethane dispersion). The migration fastness was most improved at 0.35% application. This is presumably due to the fact that the chitosan may increase the dye-binding capability through intermolecular hydrogen bonding.

• Fibers and Polymers
• /
• v.5 no.2
• /
• pp.128-133
• /
• 2004

This paper reports the effects of bleaching of alpaca tops and dyeing of bleached alpaca tops/yarns on the quality of tops and yarns. A dark brown alpaca top was bleached with hydrogen peroxide. Two bleaching methods were tried for effectiveness of color removal. A portion of each bleached top was dyed after bleaching. Color parameters were examined for unbleached, bleached and bleached/dyed tops, these tops were then converted into yarns of different twist levels and counts using a worsted spinning system. Some of the bleached yarn from each bleaching method was dyed in a package dye vat to compare the difference of top dyeing versus yarn package dyeing on yarn quality. Fiber diameter, yarn strength, yarn evenness, yarn hairiness and fiber degradation were tested to examine the effects of bleaching and dyeing on these properties at top and yarn stages. A processing route for bleaching and dyeing alpaca fiber was recommended.

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2001.11a
• /
• pp.3-11
• /
• 2001

Fundamental studies at the CSIRO division of Wool technology and ICI on the diffusion of dyes into wool〔1,2〕have let to development of a new approach to wool dyeing. In this method, the cell membrane complex of wool is modified before dyeing by treatment under mildly alkaline conditions with a special chemicals. Wool pretreated with ethoxylated quaternary ammonium salt has an increased rate of dyebath exhaustion and dye penetration early in the dyeing cycle. This enables the treated material to be dyed below the boil for a similar time to the conventional cycle. This technique can be used on untreated and shrinkresist-treated wool and wool/nylon blends. In addition to good macro-levelness and excellent coverage of tippiness, the low temperature dyeing process give higher exhaustion levels of dyestuffs and insect-resist agent and hence cleaner effluent liquors, compared with conventional dyeing process. Low Temperature Dyeing process cause significantly less fiber damage than conventional way. The reduction in damage is reflected in improved processing performance of the dyed wool.

• Journal of Fashion Business
• /
• v.15 no.4
• /
• pp.110-121
• /
• 2011

As car seat is the closest part between driver and rider, the interest of the security and comfort of the seat is increasing. This research discovered the best condition for dyeing and finishing to produce a fabric for car seat and also developed the design of fabrication to give the feeling from such a finishing. The best condition of coating finishing solution is aqueous PU 65%, dye resist reagent 20%, water 12%, thicker 3%, and knife thickness 2mm, tenter temperature $170^{\circ}C$, tenter speed 35yard/min, viscosity 12,000cps and stirring time 100kg * 30min. According to the processing time of knife coating upon stirring the change of resin and the uneven of coating quantity was shown. This problems will be solved by means of automatic temperature control apparatus for resin and sealing device through a coming research.

• Journal of the Korean Chemical Society
• /
• v.55 no.6
• /
• pp.1024-1029
• /
• 2011

PVA/silica hybrid xerogels were synthesized by sonohydrolysis of a mixture of 2-way catalyzed TEOS and water solution of PVA. PVA was successfully removed from the xerogels through calcination and its removal was confirmed through TGA analysis of the calcined gel. Microstructure of the gels was studied through SEM, XRD and FTIR. Nitrogen sorption studies were conducted to find out surface area of different samples. It was found out that the samples having PVA removed through calcinations have higher surface area (411.64 $m^2$/g) than the samples (353.544 $m^2$/g) synthesized without any PVA. Adsorption properties of these xerogels synthesized by using different ratios of components were studied by taking Rhodamine G6 as a model adsorbate. The experiments were conducted at room temperature ($25^{\circ}C$). UV visible spectroscopy was used to measure the concentration of the dye before and after adsorption. The adsorption data of Rhodamine G6 on PVA modified silica is described by the Freundlich's adsorption model.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04b
• /
• pp.250-252
• /
• 2004

나노 기술의 개발과 마이크로어레이(microarray)의 등장으로 생물학자동을 한번에 보다 라르고 신속하게, 대량의 실험을 처리할 수 있게 되었다. 이와 발 맞추어 마이크로어레이를 이용한 다양한 실험 방법들이 개발되었다. 형광 염료(fluorescence dye)를 이 용한 관찰 방법 이 널리 이용되고 있으나, 관찰되는 형광 염료의 밝기가 실험 환경(pH, 온도)에 매우 민감하게 반응하며, 단백질을 포함한 많은 분자 물질들이 형광을 내지 않기 때문에 마이크로어레이를 이용한 분석 대상 물질들의 개수가 제한을 받는다. 본 논문에서는 직접적인 형광 염료의 사용 없이, SPR(Surface Plasmon Resonance)을 이용한 마이크로어레이 분석 시스템에서 스팟(spot)의 밝기(intensity)를 측정하기 위한 효율적인 전처리 과정을 제안하고자 한다. 전처리 과정은 크게 프로젝티브 왜곡 효과 제거, 스팟의 위치 추적, 스팟의 영역 추출, 정규화 된 스팟의 밝기 측정으로 나누어진다. 특히, 이러한 과정을 거쳐서 측정된 밝기는 반응 유무의 관찰뿐만이 아니라, 실험 물질의 양적인 측정에도 이용되기 때문에 정확한 스팟의 밝기 측정에 중점을 두고자 한다.

• Textile Coloration and Finishing
• /
• v.31 no.2
• /
• pp.98-106
• /
• 2019

The dyeability and fastness properties of super-hydrophobic navy dyes having different length of alkyl groups were investigated on ultra high molecular weight polyethylene fabrics. Those dyes exhibited strong color strength in the wavelength of mainly 550~650nm, which meant that they were navy color. From the results accomplished under various dyeing conditions, it can be concluded that those dyes have higher affinity on the fibers at $130^{\circ}C$ than at the lower dyeing temperature. Considering processing time and thermal damage of the fibers, one hour is good enough to obtain full strength of color. Maximum color strength was obtained at 2~3%owf of pure dyes. Except for the rub fastness under dry condition, all fastness such as to washing and light showed as good as of 4~5 ratings.