• Fibers and Polymers
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• v.4 no.3
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• pp.124-128
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• 2003

Dark brown Alpaca fiber was reduced in shade via selective bleaching with peroxide. Two selective oxidative bleaching methods were tested on alpaca top to assess their effectiveness for color removal and fiber quality properties. Color change, bundle strength, weight loss, fiber diameter, surface modification, dye-ability and dye wash fastness were assessed for both methods and compared with the original brown top. Bleach method 1 (BL-I) showed little surface modification, 5.8% weight loss and 2.4% strength loss. D1925 yellowness index was reduced to 74.3 from 83.1 and provided a good base for the dyeing of medium to deep shades. Bleach method 2 (BL-II) displayed considerable surface modification, 7.8% weight loss and 18% strength loss. BL-II also resulted in a mean diameter reduction of 1.9 micron during bleaching. Yellowness was reduced to 64.5 from 83.1 and provided a very good base for the dyeing of medium to deep shades. BL-I showed better exhaustion of the premetallised dye Lanaset Violet B than BL-II. Wash fastness for BL-II was 1 grey scale unit poorer than BL-I. BL-II showed far better color clarity at pale depths however the wash fastness of the finished product was not good enough to maintain the depth or clarity of the color. BL-I showed poorer clarity of color but exhibited better wash fastness results.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.78-85
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• 2000

Due to environmental proessures there is increasing use of hydrogen peroxide as a total or partial substitute for chlorine based bleaching agents within ECF or TCF sequences. However, to aceive satifactory brightness using peroxide alone, stages having a combination of high temperature, pressure, pH or residence time are required. It may also have negative impact on fiber quality . Therefore, it would be of advantage if vertain means could be found to make hydrogen peroxide more effective in bleacing , via shortening treaction time and allevaiating the need for such forcing reaction conditions. This can be achieve by converting the peroxide in-situ to stronger oxidant through the use of 손 bleach activator. In this study to investigate the influence of additives, such as tetraacetylethylenediamine (TAED) and Molybdate (MO) . addition on peroxide bleaching were carried out. Under alkaline conditions the bleching additives. TAED and Mo. can react H2O2 to form peracetic acid and peroxomolybdate respectively and these generated activators can improve deliginification,. The activators make it possible to bleach the pulp efficiently at low temperature in the range 50 to 7$0^{\circ}C$. Also, addition of TAED and Mo is an environmentally friendly way of enhancing the performance of peroxide bleaching can be incorporated into TCF and ECF sequences.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.532-540
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• 2021

Sodium dodecanoyl-4-oxybenzenesulfonate (DOBS) salt is a substance that exhibits effective bleaching and antimicrobial abilities at low temperatures. A mild and efficient synthesis method of DOBS starting from dodecanoyl chloride and sodium 4-hydroxybenzene sulfonate was investigated under alkaline conditions using a water (W)-polar aprotic solvent system. First, the reaction was carried out using only water as a solvent system with the variables of temperature and time. The yield was found to be as low as about 5% in most cases under the reaction conditions of more than 30 ℃ and 1 h. In order to develop an efficient solvent system, the effect on the yield of DOBS was evaluated in various solvent systems which were prepared by changing the type of polar aprotic solvents while mixing them with the water. A solvent system in which acetone (AC) and water were mixed showed the best yield and about 82 % under mild reaction conditions (30 ℃, 1 h and atmospheric pressure) was obtained. The prepared DOBS showed good bleaching and antimicrobial activities indicating that it could be used an excellent bleach activator.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.142-160
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• 2003

Most consumers have noted hair damage following coloring treatments. Proper evaluation of hair bleaching products must be performed using quantitative assessments of hair damage, though they are difficult, because of the slight fluctuations in hair composition. In the present study, we utilized a sensitive evaluation method for hair damage and found that the amount of soluble protein fraction extracted from hair under a reducing condition, termed labile protein, dramatically increased after bleaching.(omitted)

• Journal of the Korean Graphic Arts Communication Society
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• v.1 no.1
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• pp.43-48
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• 1983

For the development of colored-proto grapby, the silver dye blech processes were extensively studied. For the first time, the developed silver was main catalyst, but recently active organic compounds are widely used as organic catalyst. They were guinoxaline and phenazine derivatives and it may forrned protonated free radical(${AH_2}^+$) under the presence of strong acid. Herewith the chemical reaction involved those catalyst and it's kinetic theory were described. Also, properties of the product with organic catalyst and improved process was reviewed.

• Journal of Korean Vacuum Science & Technology
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• v.2 no.2
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• pp.85-91
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• 1998

The electrochromic behaviors of de-magnetron sputtered tungsten oxide thin films were investigated during coloration and bleach cycles using in situ real-time spectroscopic ellipsometry. Effective medium approximation and least-squares regression analyses were employed to investigate the electrochromic process. The optical properties of the tungsten oxide film were analyzed using the oscillator model and the evolution of the process using a reaction-limited model. In these analyses, we found that two different reaction rates were associated with the process. We ascribe this behavior to the microstructure of this films.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.8
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• pp.875-884
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• 2012

Many Koreans have recently bleached their black hair to blond or a light color due to the influence of their favorite Korean idols. Bleaching effects were studied under various bleaching conditions, such as the concentration of oxidants, the ratio between bleach accelerant and oxidant, and treatment temperature and time. The degree of damage of bleached hair with the same color difference (${\Delta}E$) intervals was observed in SEM images, the retention of breaking load and the change of color after dyeing. The ratio between bleach accelerant and oxidant of 1:2.5 was an effective condition. $L^*$ values of the bleached hair treated with 9% oxidant increased to 90 min. At a treatment temperature of $30^{\circ}C$, $a^*$ values were maximum at 30 min and then decreased as time further increased; however, $b^*$ values of the bleached hair increased as the treatment time increased. At $45^{\circ}C$, both of $a^*$ and $b^*$ values showed a maximum at a specific time. Bleaching efficiency was influenced most by temperature, followed in order by time, and oxidant concentration. As the treatment time increased, $L^*$ values greatly increased with twice treatment; however, $a^*$ and $b^*$ values decreased. Bleached hair, which had a color difference of higher than 30, showed the scales were completely removed and the retention of the breaking load greatly decreased. Highly bleached hair showed a great decrease in $L^*$ values by dyeing; however, dyeing with bright colors was more indicative to the effect of bleaching.

• Fashion & Textile Research Journal
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• v.22 no.4
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• pp.534-539
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• 2020

Experimental research is needed to provide information on the removal of bloodstains since washing clothes contaminated with blood is necessary for medical related fields (such as ambulance workers and doctors) as well as for women of childbearing age. This study investigated efficient washing conditions for the removal of bloodstains with a focus on washing temperature, fiber type and blood ageing time. Polyester/cotton fabric showed the highest detergency from among three fabrics that were influenced by the composition of the fiber and the structure of the yarn and fabric. When examining the effect of detergent, it was concluded that the alkalinity over pH 10 was essential to remove bloodstains and that auxiliary agents such as soil antiredeposition agents and bleach had a significant effect on the removal of bloodstains. Washing temperature showed the highest detergency at 20℃ due to the activity of the enzyme without the denaturalization of blood. Blood-ageing influenced detergency by inducing changes in the adsorption area and chemical bond. A combination of methods such as quick removal after contamination, use of alkaline detergents including soil antiredeposition agents and bleach, and low-temperature washing could help remove bloodstains.

• Journal of Environmental Health Sciences
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• v.23 no.2
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• pp.106-114
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• 1997

When surfactants meet chlorine bleaches not only in the washing drums but also through the whole path from the stream to the river, it is not difficult to expect that they produce the harmful substances like DBPs. Furthermore considering wastewater that is contaminated by surfactants is used to discharge into drinking water sources via sewer system, it also can be imagined that residual surfactants would contribute to the some extent of DBPs' formation during chlorine disinfection in water treatment plants. Although the main behavior observed was the formation of chloroform during the reaction of LAS with free chlorine, the other manifest behaviors like the trends of pH, MBAS, free chlorine, the mole concentration of benzene ring and etc. were also investigated.

• The Research Journal of the Costume Culture
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• v.15 no.5
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• pp.852-862
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• 2007

This study was to investigate the physical properties and the external characteristics of denim fabrics(100% cotton non-spun denim, 98% cotton/2% polyurethane spun denim) such as tensile strength, thickness and weight, flex stiffness, surface color and shrinkage. The results of the study were as follows. After examining the change of external characteristics of before and after washing finishing for denim fabrics, denim with bio washing had increased pliability compared to denim without washing finishing but the pliability of the denim did not increase according to the intensity or frequency of washing. The luminance change according to washing finishing was high in the order of bio stone bleach washing, bio stone washing, bio washing and denim without washing finishing and the surface color became brighter in accordance with the increase of intensity and frequency of washing finishing.