• 한국생활과학회지
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• 제14권3호
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• pp.433-439
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• 2005

In this study, we investigated the morphological and physical changes of hair after bleaching treatments with different concentration of hydrogen peroxide in bleaching agent (3, 6, 9, or 12%) and various treatment time (10, 30, or 60 minutes). Tresses of virgin black hair were bleached using a commercial ammonium persulfate-hydrogen peroxide solution. The tensile strength of virgin hair treated with a bleaching agent depended on the concentration of hydrogen peroxide and the treatment time. As the concentration of hydrogen peroxide in bleaching agent went high and the treatment time increased, the tensile strength of the hair increased but the extension degree decreased. The virgin hairs which were not treated by bleaching agent showed morphologically healthy cuticle, whereas the bleached hairs showed swelled and damaged cuticle patterns. The swelling of the hair and the breaks of the cuticles increased positively by the concentration of hydrogen peroxide and the treatment time. These results suggest that exposure to more concentrated hydrogen peroxide with other bleaching components may lead to more severe hair damage.

• Restorative Dentistry and Endodontics
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• 제25권4호
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• pp.599-605
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• 2000

Among the effects of tooth bleaching on composite resins, degree of color change and dye deposition onto composite resins after office bleaching were investigated in vitro. Seventy two disc-shaped resin samples were fabricated with hybrid type composite resin, Z-100 under 3 different environments(24 samples for each environment) characterized by 3 kinds of light-curing intensity and duration($250mW/cm^2$-20sec., $250mW/cm^2$-40sec., $550mW/cm^2$-20sec.). As control, one-third samples of each group were not treated with bleaching agent. The remaining two-thirds samples of each group were treated with bleaching agent(bleaching group). Then, before thermocycling procedure in coffee bath, the half of the samples treated with bleaching agent were polished(polishing group) with polishing system. SofLex, but the other half(not-polishing group) and control group were not polished. Another 72 samples were also made with microfilled type composite resin. Sillux Plus and treated according to the experimental procedures mentioned above. The color of each resin sample was measured before bleaching, after bleaching, and after thermocycling preceded by bleaching. And color difference was evaluated. It was concluded as follows: 1. The amount of color change of resin samples after office bleaching was not statistically significant(p>0.05). But the samples which were treated with bleaching agent showed more color change than that of control group. 2. After thermocycling in coffee bath, the amount of color change of resin samples between control and bleaching group was not statistically significant(p>0.05). 3. After thermocycling in coffee bath, the polishing procedure of resin samples showed no statistically significant difference(p>0.05) between polishing and not-polishing group in the aspect of color change.

• Restorative Dentistry and Endodontics
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• 제45권2호
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• pp.20.1-20.14
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• 2020

Objectives: To minimize the tooth sensitivity caused by in-office bleaching, many dentists use non-steroidal anti-inflammatory drugs and topical desensitizing gels containing potassium nitrate and sodium fluoride. This study aimed to evaluate the influence of these substances on inflammation and the expression of substance P and calcitonin gene-related peptide in pulp nerve fibers. Materials and Methods: Seventy-two rats were divided into 6 groups as follows: GI, control; GII, only dental bleaching; GIII, only ibuprofen; GIV, ibuprofen administered 30 minutes before and after the bleaching treatment and every 12 hours until the analysis; GV, only topical application of a desensitizing agent; and GVI, topical application of a desensitizing agent before dental bleaching. Placebo gel was applied to the upper left jaw and the bleaching agent was applied to the upper right jaw in all groups. Subsequently, the groups were divided into 3 subgroups based on the time of analysis: 0, 24, and 48 hours after bleaching (n = 8). The rats were euthanized and the maxillae were processed and evaluated by histopathological and immunohistochemical analyses. The data were analyzed using the Kruskal-Wallis test, followed by the Dunn test (p < 0.05). Results: In the bleaching groups, the inflammatory process and expression of neuropeptides decreased over time. The animals in which a desensitizing agent was applied showed better results within 24 hours. Conclusions: The use of a desensitizing agent had positive effects on inflammation and pain-related neuropeptide expression, minimizing the painful effects of dental bleaching treatment.

• 한국융합학회논문지
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• 제6권5호
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• pp.165-171
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• 2015

본 연구의 목적은 임상에서 사용되고 있는 치아미백제와 $TiO_2$ 광촉매의 융합에 의한 치아 미백효과를 평가하고, 미백 효과를 극대화시킬 수 있는 광촉매 혼합비 등에 관한 기초연구를 통하여 미백효과와 안전성을 고찰하고자 하였다. 실험에 사용된 치아는 발거된 치아 중 우식에 이환되지 않고 수복물이 없는 전, 구치부 치아 24개의 연조직 치석을 제거한 후 전치부의 순면이나 구치부의 협면 및 설면이 노출되도록 하여 dal상에서 사용 중인 치아 미백제에 $TiO_2$ 광촉매 분말을 10, 20wt.% 첨가하여 융합하고, 과산화수소수를 10~20%첨가한 미백제를 적용하여 색조 변화를 측정하였다. $TiO_2$ 광촉매와 미백제의 융합 미백제 적용에 따른 치아의 외관 특성평가 결과, 20% 과산화수소수에 $TiO_2$ 첨가한 경우 월등한 미백효과를 나타남을 알 수 있었으며 $TiO_2$ 광촉매를 사용하면 치아미백을 위한 미백제 적용시간을 단축시킬 수 있음을 알 수 있다. 이러한 결과는 향후 치아 미백제 개발에 촉매의 활용을 통하여 미백 효과를 향상시킬 수 있는 연구의 제안으로 치아미백 제품개발에 기여할 수 있을 것이다.

• Journal of the Korean Wood Science and Technology
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• 제27권4호
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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.

• 디지털융복합연구
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• 제15권9호
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• pp.533-541
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• 2017

급변하는 21세기는 이미지 관리가 중요시 되고 이러한 흐름에 따라 모발 색의 다양화를 위한 많은 염모제와 탈색제가 사용되어지고 있지만 잦은 화학적 컬러 시술로 인한 모발의 손상은 피할 수 없게 되었다. 본 연구에서는 건강모발(A그룹)과 손상모발(B그룹)로 나누어 기본 탈색제(a)의 혼합 비율과 물을 혼합하여 농도를 희석한 탈색제(b), 오일성분을 첨가한 탈색제(c)와 물과 샴푸를 혼합한 탈색제(d)를 이용하여 모발의 형태 변화와 손상을 줄일 수 있는 방법을 연구하였다. 그 결과 여러 첨가물의 혼합으로 탈색제의 농도를 희석하여 사용해도 손상을 예방 할 수 있으나, 특히 맹검법을 사용한 실험 결과에서 동백오일성분을 첨가하여 탈색 시술을 하였을 때 감각적 진단에서 A그룹(4.83)과 B그룹(4.41) 모두 모발질감에 대한 우수한 결과는 모발 손상을 줄일 수 있다는 결론을 얻게 되었다. 이에 본 연구는 탈색제의 혼합비율에 동백오일을 첨가하여 탈색을 처리를 할 때 모발의 명도를 조절하는 기본 역할 뿐 아니라 모발손상을 최소화 할 수 있는 새로운 소재 처방의 다양한 개발로 헤어 미용 시장이 발전하기를 기대한다.

• 한국염색가공학회지
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• 제10권6호
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• pp.55-66
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• 1998

In order to investigate the detergency effects of various detergents to stained polyester & cotton fabric with solid soils such as carbon black, liquid paraffin and fat, the optimum washing conditions according to the types of washing agent, the assesment of detergency effect by the measurement of reflectance after and before washing were studied. The detergency effect of various detergents to stained polyester and cotton fabric increased by using the mixtures of bleaching and enzyme detergent. In order to obtain the excellent detergency effect, 2-step treatment, the pre-washing with bleaching agent and bleaching-enzyme mixture detergent treatment is preferred. In comparison of the detergency to polyester and cotton fabric, it is assumed that the detergency to polyester stained fabric was superior than that to cotton stained fabric because of the difference of adhesive force between soil material and fabric in preparing solid stained fabric.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.381-386
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• 2006

Many different types of bleaching chemicals and processes have been globally used for deinked pulp. Besides chlorine-free bleaching chemicals, hydrogen peroxide, and sodium dithionite that could be used without restriction for almost all types of fibers, chlorine-containing chemicals such as chlorine dioxide and sodium hypochlorite have also used throughout the world. Even though hydrogen peroxide is commonly used in newsprint, it could not effectively increase brightness. Experimental evaluation on the possibility of using formamidine sulfinic acid (FAS), a reducing agent, for bleaching a wood-containing deinked pulp has been carried out in this study. The effect of bleaching efficiency for FAS on operational conditions and chemical concentrations compaired to hydrogen peroxide in one and two stages was studied. FAS bleaching showed higher brightness at high temperature and low consistency, and vice versa for peroxide one. Bleaching with sodium silicate and DTPA in FAS and peroxide stage showed better results than cases without them. Sodium silicate and chelant seemed minimize the influence of transition metal ions, including manganese and iron ions, which induce both bleaching agents to decompose. As a result, FAS as a reducing agent seems more effective than hydrogen peroxide for increasing brightness and reducing yellowness. FAS and FAS sequence seemed more efficient than the other two stages of bleaching sequences with regard to the best brightness level obtained. When bleaching was conducted with FAS, COD load was just about one-third compared to peroxide, and brightness stability of the bleached pulp appeared better than peroxide after UV light irradiation.

• 한국염색가공학회지
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• 제24권3호
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• pp.213-220
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• 2012

In this study, we investigated the effect of natural vegetable treatment agent on the bleaching and damage of human hair during permanent wave formation. The vegetable treatment agent was prepared by fermenting the mixture of tea leaves (10g), black rice (100g), black bean (100g), corn (100g), malt (50g), and water(500g) at room temperature for 1 week. The degree of bleaching and damage was checked by Munsell value 'L' and morphological changes of hair in FE-SEM. When the hair was bleached, the Munsell value 'L' was almost same regardless of adding the vegetable treatment to the bleaching solution. But when the hair was permanently waved, the curl formation ability was high and the damage was low in the case of adding the vegetable treatment. This means that the vegetable treatment covers the scale of hair and protects the hair from the chemicals.

• 한국치위생학회지
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• 제8권4호
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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.