• Clean Technology
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• v.27 no.1
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• pp.17-23
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• 2021

Black polymer spacers are currently used for physically separating aligned camera lenses in camera modules of mobile phones. However, the mechanical properties of polymer spacers have their limits, especially in the current trend of using more lenses in thinner camera modules. Thus, copper (Cu) becomes a good candidate for those polymer spacers because of its superior mechanical properties and its inherent blackness due to its black surfaced oxides, such as copper (II) oxide (cupric oxide, CuO). The latter property is critical in quality control because the closer the color of a spacer is to black, the less light interference and flaring phenomena can occur. A standard Cu blackening process and its operational conditions were proposed in this study through a comprehensive analysis of previous research and patents. The Cu blackening process is composed of cleaning, deoxidizing, activating, blackening and sealing. The effects of operational parameters, such as the temperature of each unit process and the activator concentration, were then investigated by measuring the blackness of the Cu strips with a colorimeter. The proposed operational conditions were determined by whether the blackness of Cu strips was within the on-spec. value used in the field.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.174-176
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• 2003

유기첨가제 첨가법을 통해 개발된 저조도 전해동박을 전자파 차폐용 필터로 적용하기 위해서는 시인성을 확보하기 위한 흑화표면처리가 요구된다. 이를 위해 검토된 흑화표면처리 방법 중 흑화도, 전도성, 치수안정성 공정성에 있어서 전기도금법이 가장 우수한 것으로 나타났다. 개발된 흑화도금액계는 흑색도금조직을 $0,2{\mu}m$이하로 미세하게 노듈화시킴으로 인해 외부 빛을 산란시켜 광택을 줄이고 흑화도를 증가시켰으며 전착된 흑화도금층의 묻어남을 최소화할 수 있는 조성으로 구성되었다.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.188-207
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• 2013

This study looks at the costumes for the crown prince based on the Hyomyeong of 1817, a collection of the National Research Institute of Cultural Heritage. The picture of School Entrance Ceremony of the Crown Prince (王世子入學圖) does not have the crown prince in the scene. However, it can be verified through literature that there are three different costumes for the ceremony. Chulgungui(出宮儀), the ceremony's first procedure, describes the departure of the prince crown from his residence toward Sungkyunkwan (成均館) with his escorting officials. The Crown Prince wears Seoyeonbok (書筵服) during this event. When the Crown Prince arrives at Sungkyunkwan, he participates in a series of ceremonies that consist of Jackhunui (酌獻儀), Wangbokui (往復儀), Supeiui (脩弊儀), and Ipackui (入學儀). At that time, he wears a confucian scholar's uniform. After returning from Sungkyunkwan, he attends Suhaui (受賀儀), the final procedure of the Crown Prince's School Entrance, at Simindang (詩敏堂) of Changgyong Palace(昌慶宮), At this time, the price crown wears Wonyukwanbok (遠遊冠服) as he is congratulated by royal family members and high ranking officials for his entrance to Sungkyunkwan in this ceremony. This point hereby concludes this study on the historical costumes for the prince crown based on the Hyomyeong Crown Prince's School Entrance in 1817.

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.33-40
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• 2008

Normally, cedar heartwood has a red color. However, it frequently changes black color (blackening phenomenon). It is reported that blackening phenomenon of cedar has been caused by oxidation of phenolics and norlignan extractives under weak alkaline conditions. In this study, heat treatment and UV irradiation were carried out to reduce the difference of color value between blackened wood and bright sap wood. Effects of temperature, moisture content, treatment time and light on decrease of color difference between blackened heartwood and sapwood were evaluated in each treatment. A decrement of different color value between blackened heartwood and bright sapwood by hot-water treatment was bigger than others. An effect of the vacuum drying was similar to that of the kiln drying. UV irradiation decreases the color difference between dried blackened heartwood and bright sapwood. It is suggested that UV irradiation could be used as final treatment to reduce the color difference on wood during drying process. Determination of optimum conditions and development of hybrid process for control of discoloration will be needed in a further study.