• Journal of the Korean Society of Costume
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• v.56 no.2 s.101
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• pp.147-154
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• 2006

In this study 1, the dyeability and sun protection characteristic of the fabrics dyed with pine needles extract was investigated. In the test of color difference, the surface color of all the dyed fabric of both cotton and silk came to light as greenish yellow. In the test of dyeing colorfastness, the colorfastness to sunlight of dyed cotton fabric was below 2nd grade and the one of dyed silk fabric was below 3rd grade. The colorfastness to laundry for the degree of discoloration showed a difference as to mordants, but the colorfastness to laundry for the degree of contamination was excellent as all the dyed fabrics were 4th-5th grade. The colorfastness to perspiration was excellent as the degree of discoloration was more than 3rd grade and the degree of contamination was more than 4th-5th grade. The colorfastness to rubbing showed the excellent result as all the dyed fabrics were 4th-5th grade. In the test of sun protection factor(SPF), the cotton and silk fabrics dyed with $FeSO_4{\cdot}7H_{2}O$ mordant showed very high sun protection characteristic as the SPF was each 36.1 and 42.5. In the test of sun protection rate for UV-A and UV-B, the cotton and silk fabrics dyed with $FeSO_4{\cdot}7H_{2}O$ mordant showed the very high sun protection rate of more than $90\%$.

• Journal of Photoscience
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• v.9 no.2
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• pp.236-239
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• 2002

Sunscreens have been advocated as an important means of preventing skin cancer. UV-induced immunosuppression is important for skin cancer development, yet the effectiveness of sunscreens in protecting the human immune system from UV radiation is unclear. The only currently accepted method of sunscreen rating is the Sun Protection Factor (SPF) based on prevention of erythema. We developed an in vivo non-invasive method for evaluating protection of the human immune system from UV radiation based on recall contact sensitivity to nickel, a common allergen. Using this system we showed that broad-spectrum sunscreens provide greater protection to the immune system than sunscreens which protect from UVB only. UVA was found to be immunosuppressive. We developed this technique to enable the study of solar simulated UV radiation dose responses and determined Immune Protection Factors (IPFs) for six commercially available sunscreens based on limits of protection from the dose response data. We found that the IPF did not correlate with the SPF and that protection from erythema therefore cannot be used to predict protection of the immune system. However, IPF was significantly correlated to the UVA protective capability of the sunscreens, indicating that sunscreen protection from UVA is important for prevention of immunosuppression. We recommend that sunscreens should be rated against their immune protective capability to provide a better indication of their ability to protect against skin cancer.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.4
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• pp.349-354
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• 2023

Sunscreen is a product that protects against ultraviolet rays by blocking and scattering ultraviolet rays, and has now become a daily necessity beyond cosmetics. Applying sunscreen is a common and easy way to prevent skin damage caused by ultraviolet rays. Due to its significance, the evaluation of sunscreen has evolved since its regulation by the FDA in 1978, progressing to standardized methods established by ISO. Additionally, to assess the loss of sunscreen due to activities such as water exposure or sweating, the Ministry of Food and Drug Safety in Korea and ISO have established protocols for evaluating the water-resistant sun protection factor (SPF). However, existing evaluations of water resistance have been mainly confined to test methods involving plain water, and methods accounting for the impact of seawater during activities like beach leisure, sports, and recreation are yet to be established. Based on the existing guidelines for testing the water-resistant UV protection index, this study compared the water-resistant UV protection index in water, artificial seawater (salt water) and natural seawater (sea water) to evaluate the UV protection index in real-world situations such as marine leisure, sports, and leisure activities. Through these results, we were able to compare the differences between water resistance sun protection index tests in ordinary water, artificial seawater, and natural seawater, and suggest a method for water resistance sun protection index tests using natural seawater.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.138-138
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• 2002

In recent years, the safety of sunscreens has been challenged based on the reports of its adverse effect on users; dermatitis, allergic contact dermatitis, photoallergic contact dermatitis. To investigate a correlation between sun protection factor (SPF) and the safety of sunscreens, we measured in vitro SPF index using homosalate as a standard and examined the toxicity tests on cosmetics; primary and cumulative skin irritation tests, ocular irritation test, and skin sensitization test.(omitted)

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.20-28
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• 2020

Symbiodinium is a dinoflagellate genus that coexists with coral reefs and is known to provide ultraviolet (UV) protection in nature through the synthesis of mycosporin-like amino acids (MAA). In order to develop a natural and ecofriendly sunblock for use in summer resorts, the possibility of using a Symbiodinium microbiome extract or an MAA was investigated. Two sunblocks, one containing 7% Symbiodinium extract and the other containing MAA were prepared to be tested on hairless mice and human skin. In this clinical study, the sun protection factor (SPF) and Protection factor of UV A (PFA) values of the sunblock containing either Symbiodinium extract or MAA were determined. The SPF values of the sunblock containing Symbiodinium extract and MAA were 10.43 and 10.83, respectively, and the PFA values were 3.42 and 3.39, respectively. Based on their PFA values of ≥2, the UV A protection can be graded as PA+ (low) for both the sunblocks. In addition, the UV-blocking extract of Symbiodinium has a low phototoxicity and cytotoxicity, reducing the possibility of a heavy feeling to the skin or a foreign-body sensation caused by residue build-up. The low toxicity feature of the major sunblock component will also prevent side effects, such as allergic reactions. Although Symbiodinium extract or MAA alone do not provide effectiveprotection against UV irradiation, their protection capacity can be complemented by the addition of inorganic UV-protecting compounds.

• Safety and Health at Work
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• v.11 no.1
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• pp.61-70
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• 2020

Background: This study aims to assess whether the TSI PortaCount (Model 8020) is a measuring instrument comparable with the flame photometer. This would provide an indication for the suitability of the PortaCount for determining the workplace protection factor for particulate filtering facepiece respirators. Methods: The PortaCount (with and without the N95-Companion^TM) was compared with a stationary flame photometer from Moores (Wallisdown) Ltd (Type 1100), which is a measuring instrument used in the procedure for determining the total inward leakage of the particulate filtering facepiece respirator in the European Standard. Penetration levels of sodium chloride aerosol through sample respirators of two brands (A and B) were determined by the two measuring systems under laboratory conditions. For each brand, thirty-six measurements were conducted. The samples were split into groups according to their protection level, conditioning before testing, and aerosol concentration. The relationship between the gauged data from two measuring systems was determined. In addition, the particle size distribution inside the respirator and outside the respirator was documented. Linear regression analysis was used to calculate the association between the PortaCount (with and without the N95-Companion^TM) and the flame photometer. Results: A linear relationship was found between the raw data scaled with the PortaCount (without N95-Companion^TM) and the data detected by the flame photometer (R² = 0.9704) under all test conditions. The distribution of particle size was found to be the same inside and outside the respirator in almost all cases. Conclusion: Based on the obtained data, the PortaCount may be applicable for the determination of workplace protection factor.

• Analytical Science and Technology
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• v.30 no.4
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• pp.159-166
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• 2017

Exposure to UV light, i.e., UV-A (320-400 nm) or UV-B (290-320 nm) radiation, can cause skin cancer. Titanium dioxide ($TiO_2$) effectively disperses UV light. Therefore, it is used as a physical UV filter in many UV light blockers. Usually, the $TiO_2$ content in commercialized UV blockers is 25 % at most. To block UV-B, a chemical UV blocker, octyl-methoxy cinnamate (OMC) is used. OMC is commonly used in combination with $TiO_2$. In this study, $TiO_2$ and OMC were mixed in different proportions to produce UV blockers with different compositions. Also the changes in the sun protection factor (SPF) based on the composition and $TiO_2$ particle sizes were investigated. In order to analyze the $TiO_2$ particle size, dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AsFlFFF) were used. The results showed that the SPF was influenced by the proportion of $TiO_2$ and OMC, where the proportion of $TiO_2$ induced a more significant influence. In addition, changes in the $TiO_2$ particle size based on the proportion of OMC were observed.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.411-416
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• 2005

The aim of the present work was to prepare the nanosuspension of inorganic pigment which shows light reflection and scattering as efficient sunscreen. The zinc oxide (ZnO) was chosen as an inorganic pigment, and high pressure homogenizer and bead mill have been used for the preparation of nanosuspension. The ZnO nanosuspensions were characterized by particle size, in vitro sun protection factor (SPF) and UV transmittance. ZnO nanosuspension prepared by bead mill showed the average diameter of $119{\pm}4\;nm$, resulting in the high value of SPF $(28.74{\pm}2.06,\;n=20)$, while that prepared by high pressure homogenizer showed the average diameter of $751{\pm}32\;nm$ with the relative lower value of SPF $(21.38{\pm}1.94\;n=20)$. In addition, the film of ZnO nanosuspension prepared by bead mill was showed a high visible ray (VIS) transmittance, indicating a high transparency. In conclusion, a physically stable ZnO nanosuspension in cyclomethicone was successfully prepared using bead mill for the suitable sunscreen preparations.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.4
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• pp.490-500
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• 2010

This study, at first we extracted natural dyes from seaweed(Sargassum thunbergii, Hizikia fusiforme, Sargassum horneri). Then. we dyed cotton, wool, and silk with the extracted dyes. This study purposes to find the best one for dyeing with seaweed in order to develop a more efficient method of dyeing with seaweed and investigates the colorfastness to washing, light, sun protection factor, antibiotic activities, deodorization after mordanting treatment. of seaweed. The mission of general agricultural education is to prepare and support individuals for careers, build awareness, and develop leadership for the food, fiber, and natural resource systems. In response to the changes of the recognition and attitude toward agriculture, agricultural education also should be developed and adapted to the circumstances. And The Researcher took an observation on color change, color fastness to washing and color fastness to light after mordanting treatment. And the following results have been obtained. 1) Dyed cotton, wool, and silk fabrics with the extract of seaweed are generally brown. 2) Wool. silk, and cotton, in this order, are of good dyeability; Wool fabrics have the highest dyeability and cotton fabrics have the lowest. 3) Colorfastness to washing, light, sun protection factor, antimicrobial activity acessment, deodorization are all high. 4) The seaweed-dyed fabrics were shown to have much higher sun protection factor than the non-dyed fabrics, and the seaweed-dyed fabrics with mortanting treatment showed the following result; ranged from anged from from 93.1% to grade 99.2%. 5) The seaweed-dyed fabrics were shown to have much higher antibiosis than the non-dyed fabrics, and the seaweed-dyed fabrics with mortanting treatment showed the following result; ranged from 91.3% to grade 99.9%. 6) The seaweed-dyed fabrics were shown to have much higher deodorization than the non-dyed fabrics, and the seaweed-dyed fabrics with mortanting treatment showed 99.9%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.140-141
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• 2006

Background doping concentration (BDC) is proven to be a critical factor to affect the high current behavior of the extended drain NMOSFET (EDNMOS) devices. The EDNMOS device with low BDC suffers from strong snapback in the high current region, which results in poor electrostatic discharge (ESD) protection performance and high latchup risk. However, the strong snapback can be avoided in the EDNMOS device with high BDC. This implies that both the good ESD protection performance and the latchup immunity can be realized in terms of the EDNMOS by properly controlling its BDC.