• Textile Coloration and Finishing
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• v.12 no.5
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• pp.288-294
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• 2000

The dyeing of Tencel fabric with Coptis chinensis Franch was studied. The colorant was extracted with distilled water under various concentrations of dyestuff, times, mordants. UV-VIS spectra were obtained to find the maximum wavelength and absorbance of colorant. Tencel fabric was dyed with different mordants in pre and post-mordanting methods. Maximum wavelength of spectrum was 343 nm, and K/S value of pre-mordant was higher than post-mordant. Aluminium and stannic mordants changed color from yellow to blue-greenish and red-bluish. Colorfastnesses of light, and washing were low grade, but that of perspiration was increased.

• Textile Coloration and Finishing
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• v.8 no.4
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• pp.52-58
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• 1996

Until now, in case of natural dyeing, the appearance of medium colors were achieved by repeat dyeing with different colorants after dyeing with one colorant. In this study, however, new dyeing method for appearance of medium colors was developed by use of mixing solution of different colorants prepared with the same ratio using colorant concentrates. In combination dyeing, purple color was difficult to represent because of the Gardenia blue dye among the colorants used in this study was naby blue dye. But the other medium colors such as yellow red, green yellow, green and blue green were easily represented by use of reddish Sappan wood and yellowish Gardenia concentrates. If the natural blue dye is prepared in concentrate condition, the dyeings dyed in various colors may be obtained by combination dyeing.

• Current Research on Agriculture and Life Sciences
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• v.28
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• pp.9-15
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• 2010

Extraction Efficiency of colorants from sorghum and its storage stability were examined according to the various extracting and storage conditions in this study. The obtained results were as follows ; The absorbance values of extracted colorants were increased with increasing extract time and temperature. The extraction at pH 4 extract was most efficient among the various pH conditions. In the juice extractor system, the amount of extracted colorant was more in distilled water pre-treatment than pH 5, but it was more in pH 5 in the long time pre-treatment above 20 hour. The color of extract solutions changed through variation of the pH. Its color changed from light yellow to heavy yellow finally red ton by pH increasing. The Methionine addition gave an effect on the storage stability of colorant solution and then had better storage stability. And so it delayed the color change up to storge period 18th day and the stabilizing effect was revealed in order of Methionine 10mmol-addition>20mmol-addtion>non-addtion.

• Journal of Fashion Business
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• v.18 no.5
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• pp.69-81
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• 2014

Fabric made of 100% silk was dyed with Undaria pinnatifida extracts under different conditions such as varing colorant concentration, temperature, time and dyebath pH. The dye uptake (K/S, value), CIE L*,a*,b* and Munsell values of the dyed samples and mordanted samples were measured. Colorfastness, antibacterial property and UV protection property were also evaluated. As colorants concentration increased, the dye uptake increased progressively and maximum color strength was obtained at 100% V/V. Dye uptake also increased with increasing temperature and time, and the maximum color strength was obtained at $80^{\circ}C$ and 60min. With pre-mordanting, the color of the Al and Fe mordanted silk fabrics was yellow on the Munsell color system, while the Cu mordanted fabric was a greenish color. Al and Fe post-mordanted fabrics had a yellow tone, and the Cu post-mordanted fabric had a yellow greenish tone. The light fastness property of the Cu mordanted silk fabric was relatively good, The effect of Al and Fe mordanting on fastness was insignificant. The antibacterial activity of dyed and unmordanted silk fabric was excellent, whereas fabric dyed and mordanted with Undaria pinnatifida extract demonstrated superior ultraviolet protection.

• Journal of the Korean Home Economics Association
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• v.46 no.7
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• pp.1-6
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• 2008

The purpose of this study was to investigate the changes in properties of silk fabrics dyed with safflower red and yellow colorants under Ultraviolet(UV)-light. Silk fabrics dyed with safflower red and yellow colorants were compared with each other after uv-light exposure in terms of K/S value, color changes(${\Delta}E$), morphology, and strength retention. The K/S value rapidly decreased with increasing exposure time for samples of both colorants, but the extent of decrease was less for the samples dyed with safflower yellow colorant, than that of the samples dyed with safflower red colorant. Regarding the color changes with increasing exposure time, $L^*$ and $b^*$ increased, $a^*$ decreased, and thereby ${\Delta}E$ increased in the red-dyed samples, whereas $L^*$ increased, $a^*$ and $b^*$ decreased, and so ${\Delta}E$ increased in the yellow-dyed samples, indicating that the UV-light induced fading and changes of hue, value and chroma value. However, the color change of the yellow-dyed samples was less than that of the red-dyed samples. SEM images showed a severe degradation by UV-exposure for both colorant samples. Tensile strength slowly decreased until 14 days, but rapidly decreased thereafter. Strength retention of the yellow-dyed samples was higher than that of red-dyed samples.

• Textile Coloration and Finishing
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• v.24 no.3
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• pp.165-172
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• 2012

The stability of yellow and red dyes prepared from safflower (Carthamus tinctorius L.) in aqueous solution and in solid state was investigated. External factors such as light irradiation and temperature on the stability were examined during storage. Changes in absorbance of dye solutions and the color changes of fabrics dyed after long time storage were measured. Also, color reproducibility during storage was investigated by dyeing test on various fabrics. Red colorant in aqueous solution was very unstable to light, resulting that about 40% of absorbance were lost in 12hrs. The absorbance of yellow dye solutions was not decreased within 84hrs. In aqueous medium, yellow dye was much more stable than carthamin. Both dyes are relatively stable for long storage when they are stored in solid state compared to when in aqueous solution. Color changes are marginal in both dyes.

• The Korean Journal of Food And Nutrition
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• v.6 no.4
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• pp.322-328
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• 1993

A study of general characteristics of acetone extracted pigment from the cell mass of Rhodospirillum rusrum DSM 467 was carried out for the development of natural food colorant. Through visible absorption scanning, it showed seven absorption peaks at 355, 410, 529, 624, 680 and 747nm, and it was shown to be yellow color. In acidic and neutral conditions, the color was yellow, while in the alkaline condition it was greenish yellow. This pigment was stable at pH range between 3.0~10.0, and below 4$0^{\circ}C$. In the presence of light and oxygen, the stability of pigment rapidly degraded and it became unstable in the presence of metal ions such as Cu2+, Al3+ and Fe3+. Through TLC analysis, it was shown to be composed of seven color fractions.

• Fashion & Textile Research Journal
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• v.21 no.1
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• pp.112-119
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• 2019

This study had a purpose of further investigating and developing the usage of the eco-friendly functional dye that has physiological and pharmacological functions. This study was implemented complex dyeing method which used both natural dyes such as Gardenia jasminoides J.Ellis colorant, which are the yellow dyes that have high brightness and low chroma, and Xanthium strumarium L. extract. The silk fabrics were used to dye in various methods. They were also used to investigate functionalities dyed fabrics by various treating method, such as their color fastness, antibacterial activities and deodorization, the following were obtained. The fabrics that were dyed with herbs had decreasing brightness as the herbs extract concentrations were increased and had subtly changing chroma. But, because their K/S values were under 0.5, they were not properly dyed. Color fastness differed according to the natural dyes and herbs' complex dyeing order. The Color fastness was good when the fabrics were dyed with the colorant first, and then with the herb. When the fabrics were dyed with mixture dyeing solution, the natural dye and the herb extract, the herb didn't affect the dyeabilities of fabrics as much. When the fabrics were dyed with the mixture of the colorant and the herb extract, the dyeabilities didn't have much changes. However, their color fastnesses were improved a little bit due to the complex dyeing condition. When the fabrics were dyed with the mixture of the colorant and the herbs extract, their antibacterial activities and deodorization were increased.

• Textile Coloration and Finishing
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• v.15 no.6
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• pp.47-54
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• 2003

To be dyed with cationic Berberine, the cotton fiber was modified with reactive anionic agent. The Berberine, a natural cationic colorant of pure yellow, is the major component of Amur Cork tree extract and also can be employed as a natural antimicrobial agent due to its characteristic of cationic quaternary ammonium salt. By LC/MS analysis, it became obvious that the Berberine was contained in Amur Cork tree extract as a major color component. The adsorption of the Berberine on the cotton fabrics pretreated with the anionic agent was greatly increased comparing to that of untreated fabric. Because the anionic agent was colorless, it did not cause unintended color change of the dyeings. The dyed fabric with the Berberine has strong antimicrobial activity showing 99.5% of reduction of bacteria against Staphylococcu aureus.

• Textile Coloration and Finishing
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• v.11 no.1
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• pp.9-15
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• 1999

Using water and methanol, the colorant components were extracted from the heartwood of amor cork tree which is known as the oldest natural yellow dye. The dyeabilities of the colorant on cotton and the fastness of cotton fabrics dyed with amur cork tree extracts were investigated. According to the dye uptake and mordant concentration, antibacterial activities and deodorization properties of dyed fabrics were also investigated. As a results, K/S values of dyed fabrics were increased with concentrations of mordants and amur cork tree extracts. Washing fastness of dyed fabrics was very low, light fastness was fair and the other fastness were good. Deodorization rates of dyed fabrics were increased in proportion to concentrations of amur cork tree extracts. The reduction rates of bacteria measured by Bioassay tests were also increased in proportion to concentrations of mordants and amur cork tree extracts.