• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.84-96
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• 1998

This study was carried out to bleach the Pinewood kraft pulp without the elemental chlorine using the xylanase or wastewater(We:wastewater enzymes) effluented from the submerged biofilter reactor containing the fungi, Phanerochaete sordida YK-624. So in this research, the proper treatment conditions(pH, temperature, dosage and time) were investigated respectively. And after the various kinds of multistage bleaching of pulps, the properties of pulps were tested. From the experimental results, we can conclude as follows. In the treatments of Pinewood kraft pulps with xylanase, the proper pH, temperature, enzyme dosage and time were 8.0, $35^{\circ}C, 400EXU/kg and 3 hr. respectively. And in the case of treatment with a wastewater(We) effluented from the submerged biofilter reactor, the proper pH, temperature and time were 5.0, $37^{\circ}C and 3 hr. respectively. On the other hand, Pinewood kraft pulps were bleached by the method of a multistage bleaching using xylanase or We instead of elemental chlorine. Consequently, the strengthes and brightnesses of pulps bleached by the method mentioned above were lower than those of pulp bleached by the conventional method using the elemental chlorine. But it is possible to improve the brightnesses through the increase of chlorine dioxide dosage or use of hydrogen peroxide in the final bleaching stage.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.3
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• pp.494-512
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• 2022

Hair toners containing polyphenol or Vitamin B5 were investigated according to their recovering effects on hair damaged by bleaching. Surface morphology, CIE L*a*b* values, and tensile properties of hair were measured. The amount of protein leaking from hair was investigated using the Bradford protein assay. The amino acid composition of hair was examined using the HPLC instrument. Hair became severely damaged after bleaching, showing cuticle structure with surface melt down and rolled up tip, a decrease in tensile strength, an increase in protein leak, and an increase in the proportion of cysteic acid. When bleached hair was treated with the two types of hair toner, positive effects were seen in the recovery of cuticle structure and retention of bleached color, an increase in tensile strength, a decrease in protein leak up to certain days, and an increase in the retention of protein examined by the HPLC analysis of amino acids. Hair treated with B5 toner showed better effects on the increase of tensile strength compared to the hair treated with PP toner. Hair treated with PP toner showed better retention of color, less protein leak, and a lower proportion of cysteic acid compared to the hair treated with B5 toner.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.3
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• pp.84-99
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• 2001

This study was carried out to acquire basic data necessary for the use of rice-straw chemical pulp. It investigated the proper bleaching conditions when rice-straw chemical pulp(alkaline sulfite-${Na_2}{S_2}{O_4}$) was bleached using the various kinds of bleaching agents by the two-stages bleaching methods. And, physical properties of pulps bleached with eight kinds of two-stages bleaching methods were tested. The results of this study were as follow; 1. The first-stage bleaching was conducted under the proper conditions with chlorine(C). And then, the proper conditions related to the calcium chlorite(H), hydrogen peroxide(P) and sodium hydrosulfite(Y) bleaching as the second-stage bleaching were investigated. The proper conditions of CH stage were determined to be 0.3% concentration of calcium chlorite, $30^{\circ}C$ of reaction temperature and 20min. of reaction time. For CP stage, the proper conditions of concentration of hydrogen peroxide, reaction temperature and reaction time were 1.5%, $60^{\circ}C$ and 90min., respectively. And for CY stage, the proper conditions were 0.5% concentration of sodium hydrosulfite, $40^{\circ}C$ of reaction temperature and 90min. of reaction time. 2. The first-stage bleaching was conducted under the proper conditions with chlorine dioxide(D). And then, the proper conditions related to the calcium chlorite(H), hydrogen peroxide(P) and sodium hydrosulfite(Y) bleaching as the second-stage bleaching were investigated. The proper conditions of DH stage were determined to be 0.5% concentration of calcium chlorite, $25^{\circ}C$ of reaction temperature and 5min. of reaction time. For DP stage, the proper conditions of concentration of hydrogen peroxide, reaction temperature and reaction time were 1.0%, $70^{\circ}C$ and 90min., respectively. And for DY stage, the proper conditions were 0.3% concentration of sodium hydrosulfite, $50^{\circ}C$ of reaction temperature and 20min. of reaction time. 3. The first-stage bleaching was conducted under the proper conditions with calcium chlorite(H). kAnd then, the proper conditions related to the hydrogen peroxide(P) and sodium hydrosulfite(Y) bleaching as the second-stage bleaching were investigated. The proper conditions of HP stage were determined to be 0.3% concentration of hydrogen peroxide, $30^{\circ}C$ of reaction temperature and 60min. of reaction time. For HY stage, the proper conditions of concentration of sodium hydrosulfite, reaction temperature and reaction time were 2.5%, $60^{\circ}C$ and 30min., respectively. 4. When the rice-straw chemical pulps were bleached with eight kinds of two-stages bleaching methods in the proper conditions mentioned above, respectively, the final brightnesses after CH, CP, CY, DH, DP, DY, HP, and HY bleachings were 62.0, 74.3, 61.4, 58.9, 66.9, 62.9, 50.4 and 60.1, respectively. And strengthes of pulps bleached with DP and DH methods were comparatively higher than those of pulps bleached with other bleaching methods.

• Journal of the Korean Chemical Society
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• v.7 no.1
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• pp.42-46
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• 1963

• Textile Coloration and Finishing
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• v.1 no.1
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• pp.35-46
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• 1989

Experiments described in which cotton fabrics at different stages of chemical processing were abraded to different extents on a Stoll Abrasion Tester with three different abradants, namely, a worsted fabric, flax fabric and silicon carbide paper. The four different plain-weave cotton fabrics selected were 1) desized, 2) scoured and bleached, 3) mercerized, 4) resin-treated. The surface abrasive damages of treated fabrics were observed by SAM, and load-elongation percent retentions of abraded samples were measured by Instrong Tester. The result were as follows: 1. The maximum percent retention of load-elongation with three different abradants was exhibited by the scoured and bleached fabrics and the minimum by the resin finished fabric. 2. The electron micrographs of four different cotton fabrics abraded by flax, worsted fabric abradants for 900 rubs showed a large number of criss-crossing stray fibers in fabric structure. It may be the molecular adhesion for frictional resistance to be explained. 3. The electron micrographs of four different cotton fabrics abraded by silicone carbide abradants showed the form of busing or mashing fibers in fabric structure. The above might be on the basis of the ploughing theory.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.67-74
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• 2004

This study was carried out to investigate the characteristics of handsheets made from nonwoody New-Zealand hemp (Phormium tenax) fibers that was not used before in Korea. The results were as follows : 1. Physical properties of bleached phormium fiber were satisfactory for handsheet forming. Specially, tensile strength was improved by adding bleached phormium fiber. 2. Opacity of handsheet with phormium pulp was fine, therefore it can be useful fiber to improve opacity of light-weight printing paper. 3. Filler retention rate was improved when phormium pulp was added, while drainage time was increased. 4. Phormium fiber has good characteristics as pulp for paper manufacture. So it can be valuable non-wood fiber resource if drainage problem is solved.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.65-71
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• 1999

This study was carried out to investigate the effect of xylanase pretreatment of the unbleached hardwood kraft pulp during the conventional Chlorine-Extraction- Hypochlorite (CEH) bleaching on pulp property. Optimum bleaching condition was evaluated by using Novozym produced from the fungus Humicola insolens. Also the effect of chelating agent prior to enzyme treatment was analyzed. The kappa number of enzymatic bleached pulp at the enzyme charge 10 IU/ml was slightly similar to that of bleached pulp without enzyme. By enzyme treatment, the chlorine charge in conventional CEH bleaching process of hardwood KP could be reduced by 17%, while no adverse effect on pulp yield and strength was. The optimum condition for enzyme pretreatment was 10 IU/ml xylanase charge, 3 to 4 hrs treatment, and 2% pulp consistency. In sugar composition in the enzyme pretreated pulp, arabinose and mannose were not much different, but more xylose was retained. This high content of hemicellulose in pulp seems to play an important role in pulp properties. The pulp pretreatment by chelating agent prior to enzyme treatment could improve the enzyme activity and enhance the bleaching effect at 0.2% diethylenetriamine pentaacetic acid (DTPA) charges.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.1
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• pp.64-74
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• 2001

This study is to find the effect of the molecular weight distribution of components on the freeness and physical properties of paper by observing the change of properties according the modification of fibers by using production technology and process technology together to develop additives which can effectively control according to the purpose of paper-making process and by combining low molecular weight cellulase (below MW 20,000; CMC activity 400 unit) with different enzyme's molecular weight and activity and high molecular weight cellulase(MW 20,000∼80,000;CMC activity 90,000 unit) and then process them in Sw-BKP(Softwood Bleached Kraft Pulp) and Hw-BKP(Hardwood Bleached Kraft Pulp) and Cotton Linter Pulp and OCC(Old Corrugated Container) with different properties of pore of surface of fibers respectively, since it is judged that making the appropriate composition ratio of components is necessary in consideration of the properties of fibers and paper-making process.

• Textile Coloration and Finishing
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• v.24 no.1
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• pp.27-32
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• 2012

Generally, hair treatments by complementary actions to give a sense of activity are permanent setting, dyeing, and bleaching, etc. In this study, we investigated the wave formation ability and hair damage occuring in permanent setting and bleaching process. The wave formation ability was evaluated by the differences of length and curl diameter after permanent setting. And the hair damage was also evaluated by the protein release ability and SEM of hair. The bleached hair immediately after permanent setting treatment has better wave formation ability, but much more damaged than the bleached hair after rinsing thoroughly with warm water. It was considered that the chain of hair keratin broke down easily by the bleaching action in the existence of permanent setting agents.

• Journal of Korean society of Dental Hygiene
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• v.8 no.4
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• pp.11-18
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• 2008

The purposes of this study were to examine the effect of 35% Carbamide Peroxide(CP) bleaching agent on the changes in physical and chemical characteristics of tooth. The effect of bleaching agent on enamel was analyzed using Hardness test, SEM and EDS. The microhardness between bleached groups after bleaching showed statistically significant difference according to the paired t-test. The bleached enamel surface showed apparent morphological changes compared to the enamel, which was stored in distilled water only. The difference of the total mineral contents for the distilled water and Carbamide Peroxide did not show statistical significance. These results demonstrated that bleaching using 35% Carbamide Peroxide were adversely affects application time of experimental group and may the safety of using these agents for a short time in dentist-monitored bleaching.